Yearly Archives: 2020

Treatment of lesser metatarsophalangeal joint plantar plate tear via Extracorporeal Pulse Activation Technology (EPAT) with MRI Follow-up: A case report

by Ziad G. Labbad MD DPM Cped1, Ebony Love DPM DABPM1*, Deep N. Shah DPM2, Yusuke Kihira DPM2, Vsevolod Grinberg DPM2

The Foot and Ankle Online Journal 13 (2): 5

Predislocation syndrome has recently gained attention as a common cause of lesser metatarsophalangeal joint (MTPJ) instability, contributing to tenderness, edema, and forefoot pain. The efficacy and utilization of non-operative treatments of plantar plate tears remains controversial; no current studies have conclusively indicated a successful restoration of a plantar plate tear by conservative treatment modalities. Within seven weeks, five total EPAT treatments were administered. Each weekly treatment consisted of 3000 pulses at 2.8 bars, performed directly at MTPJ 2-4 of the affected left forefoot. The patient was monitored on a weekly basis and progress measured utilizing the pain analog scale (0-10), subsequent MRI scans, and a complete return to normal, pre-injury activity. In the final follow-up examination, two months after the first EPAT treatment, the patient reported pain-free ambulation and a complete return to full normal activity. Subsequent MRI scans revealed no evidence of defects with notable improvements in structural integrity to the previously torn plantar plate. The results of this case report demonstrate the potential viability of shockwave therapy for the treatment of plantar plate tears. Further investigation may help to challenge the current standard of care and to provide a better, modern solution to an age-old debate between operative and nonoperative treatments of plantar plate tears

Keywords: plantar plate, metatarsophalangeal stability, lesser metatarsophalangeal joints, Extracorporeal Pulse Activation Treatment

ISSN 1941-6806
doi: 10.3827/faoj.2020.1302.0005

1 – Faculty, Temple University School of Podiatric Medicine
2 – PGY-4 Temple University School of Podiatric Medicine
* – Corresponding author:

Pain and agony at the lesser metatarsophalangeal joint (MTPJ) are a typical objection, and a few causes have been depicted including injury, instability, synovitis, and other incendiary conditions [1,2]. Chronic inflammation of the fibrocartilaginous anatomy can lead to a tear and eventual luxation of the lesser metatarsophalangeal joints. If not treated appropriately, the plantar plate injury could further predispose the patient to a multitude of forefoot pathologies. The significance of the plantar plate as a static limitation to lesser MTP joint stabilization and separation has been very much recorded, and injury of the plantar plate assume a critical job in the advancement of sagittal plane MTPJ instability [3]. In this way, predislocation disorder has as of late picked up consideration as a common cause for lesser MTPJ instability, adding to tenderness, edema, and forefoot torment.

Historically, surgical repairs of plantar plate tears have resulted in poor outcomes [4]. Generally, the operative treatment of lesser MTPJ instability incorporated an assortment of methods including synovectomy, capsular delicate tissue releases with reefing, flexor to extensor ligament exchange, phalangeal and metatarsal osteotomies, and even digital amputation. Distal metatarsal osteotomies yielded great outcome for decompression and realignment of the included joint, at the same time, none of these surgical techniques tended addressed the main cause of MTPJ instability which is plantar plate rupture [5,6,7]. As a result, the efficacy and utilization of non-operative treatments of plantar plate tears remains controversial; no current studies have conclusively indicated a successful restoration of a plantar plate tear from conservative treatment modalities.

In addition, despite numerous indications, benefits, and its well documented efficacy, previous research regarding the use of EPAT in the lower extremity has been predominantly limited to plantar fasciitis [8,9]. and Achilles tendinopathy. Little has been published regarding the use of shockwave therapy for the treatment of a partially torn plantar plate. As such, conclusive evidence recommending EPAT for the treatment of plantar plate injuries is lacking. This case study details the rehabilitation of a partially torn plantar plate at the metatarsophalangeal joints 2-4 via shockwave therapy (EPAT) confirmed via serial MRI.

Case History

A 47-year-old female started experiencing pain at the metatarsophalangeal joint (MTPJ) 2-4 of her left foot as a result of extensive ambulation on cobblestone streets. Upon a forefoot evaluation, she reported a score of an 8 on the 0-10 numeric pain rating scale (NPRS), and complained of significant localized pain. Her initial clinical presentation consisted of pain on palpation at the plantar proximal phalangeal bases 2-4, and moderate swelling at the dorsal forefoot. Additionally, a gait evaluation revealed guarding, and limping on the affected limb.


Figure 1 Partial thickness tear at the distal insertion of plantar plate at (a) second, (b) third and (c) fourth into proximal phalanx as indicated by hyperintensity (red arrow) on sagittal STIR images. Reactive joint effusions present.


Figure 2 Custom orthoses.

A subsequent MRI scan, evaluated by an external radiologist, revealed partial-thickness tears of the plantar plates of her lesser MTP joints 2-4, with reactive joint effusions at MTP joints 1-5 (Figure 1).


Figure 3 Alignment evaluation of patient weight bearing on orthoses.

Electing to avoid invasive surgical interventions, the patient was recommended EPAT as a primary treatment modality (with the addition of a custom molded orthosis (CMO) with metatarsal sling pad, as adjunctive treatments) (Figures 2, 3), which she agreed to.

Each treatment consisted of 3000 pulses at 2.8 bars. After the initial EPAT treatment, a significant reduction in pain was reported by the patient (5/10 on NPRS), and she was advised to avoid using NSAIDs and limit weight bearing on the affected area. After a second EPAT treatment, she was still unable to walk with standard footwear, however she reported a further decrease in her pain level to a 4/10 NPRS. After three EPAT treatments, three weeks after her initial treatment, she reported a 1/10 NPRS pain at rest, and 5/10 NPRS on ambulation. The clinical evaluation revealed that the joint was gaining stability, and on deep palpation, was less painful when compared to the initial examination. She was advised to transition to weight bear as tolerated (WBAT) while wearing the custom molded orthotics with metatarsal pads which were obtained at that time.


Figure 4 Lack of hyper intensity at insertion of plantar plate into proximal phalanx of (a) second, (b) third, and (c) fourth toe. Plantar plate insertion (blue arrow) shows homogeneous hypo intensity on sagittal STIR images.

At her seventh week follow-up appointment, and after five EPAT treatments, mild pain upon palpation was noted only at the second proximal phalanx with a NPRS score of 2/10, and no pain was elicited on deep palpation and passive range of motion (PROM) of 3rd and 4th MTP joint. Otherwise, she expressed a 0/10 NPRS at rest and upon ambulation. Upon clinical examination, the MTP joints 2-4 were stable on a dorsal drawer test, with no swelling present.

In the final follow-up examination, approximately two months after the first EPAT treatment, the patient disclosed that she was able to return to the same level of activity that she had before her injury. Additionally, when compared to her contralateral foot, the patient stated that she experienced neither pain nor edema. Furthermore, her second through fourth MTP joints were stable, and were not tender on palpation, nor on ambulation. A final MRI scan, obtained five and half months after the last EPAT treatment, revealed evidence of repair of her previously torn plantar plate, and improvement in the structural integrity of the plantar plate of her second through fourth MTP joint with no evidence of predislocation phenomenon (Figure 4).


The patient was closely monitored on a weekly basis and progress was measured by a notable decrease in reported pain on the pain analog scale (0-10). Within seven weeks, the patient reported pain-free ambulation without stiffness and complete return to full normal activity. The pre-treatment sagittal Short TI Inversion Recovery (STIR) MRI images demonstrated increased intensity at the distal insertion sites of plantar plates into proximal phalanges at MTP joints 2-4 (Figure 1). Partial-thickness tearing of plantar plates 2-4 with reactive joint effusions of MTPJs 1-5 was determined by an independent radiologist. The post-treatment MRI revealed homogeneous hypointense signal at the distal insertions of plantar plates 2-4 into proximal phalanges (Figure 4). Per an independent radiologist, no plantar plate defects or evidence of partial tears were noted on the post-EPAT MRI scan.


This case report demonstrates the potential viability of shockwave therapy for the treatment of plantar plate tears and furthermore, advocates the need for medical providers to reevaluate the standard of care for such pathologies. By directly correlating a reduction in pain to the associated physiological process of healing, improvements could be evaluated. Thus, the course of healing of the previously torn plantar plate was determined using pain as a critical indicator. Subsequent MRI scans and the complete return to normal activity were objective findings that confirmed the full revitalization of the plantar plates. In our case study, therapeutic EPAT treatments facilitated the full recovery and rehabilitation of a previous plantar plate tear in just seven weeks (five treatments). The capacity of EPAT therapy to promote healing is evidenced by the significant reduction in total treatment time. The absence of additional or otherwise invasive operative procedures seems to substantiate the sole use of shockwave therapy for the treatment of plantar plate tears.

Despite notable findings presented in this case study, further investigation is required to fully appreciate the role of EPAT in the non-operative management of plantar plate injuries. Several notable factors likely influenced our results and must be addressed for the sake of future studies. As stated earlier, throughout this study, the physiological process of healing was monitored and determined by 3 main parameters: patient reported pain, pre- and post-treatment MRI scans, and the complete return to normal activity. However, these parameters are not without intrinsic flaws. Notably, the reduction in pain was monitored on a weekly basis by a patient reported score on a 10-point analog scale. However, not only is pain subjective, but the correlation between a reduction in pain and the physiological process of healing is widely debated. A reduction in pain may suggest healing but is not always a definitive diagnostic measure, as additional comorbidities may mask underlying pathologies. As such, to say that the plantar plate is healing because of a reduction in pain is very plausible, but still an assumption nonetheless. Conversely, an MRI would provide much more objective or definitive findings in regard to monitoring the healing process of the plantar plate. However, the timing and chronology in which the MRI scans were obtained in this study was less than ideal. The initial MRI revealed partial-thickness tears of the plantar plates of lesser MTP joints 2-4. A subsequent and final MRI, however, was not obtained until five and half months after seven weeks of EPAT treatment, which confirmed full resolution of the previously torn plantar plate. As such, the rehabilitation of the plantar plates and the healing process was almost exclusively monitored by clinical examination and the gradual reduction in reported pain. Ideally, MRI scans could have been obtained in shorter increments of two to three weeks to definitively confirm clinical findings (stability and reduction in pain). However, due to cost, MRI’s were not obtained in such a manner.

The third parameter in which the rehabilitation of the plantar plates was determined, was the patient’s complete return to normal activity. Again, this functional outcome measure, although appropriate, is patient reported, and therefore subjective: we cannot say with certainty that the patient had regained her pre-injury strength and mobility.

Another notable factor that must be addressed is the natural biological course of healing. Although less likely, we cannot rule out a “placebo effect” in which the patient reported a gradual decrease in pain scores which was attributed to EPAT therapy. The partial-thickness tears of the plantar plate may have followed a biological healing process, exclusive of the effects of EPAT therapy. This theory, however, is less likely due to numerous studies detailing the difficulty of treating plantar plate tears and their notable lack of resolution [4,10,11,12].

Despite such possible intrinsic shortcomings, this case report demonstrates the potential viability of shockwave therapy for the treatment of plantar plate injuries. Further studies must be performed to provide conclusive evidence recommending EPAT. In addition, guidelines such as the number of treatments, the number of pulses per treatment, and/or the frequency of each pulse must be established. This unique case study was conducted by utilizing recent advancements in technology in hopes of challenging the current standard of care. Our findings were consistent with our goals to provide a better, modern, solution to an age-old debate between operative and nonoperative treatments of plantar plate tears.


The results of this case report demonstrate the viability of shockwave therapy for the treatment of plantar plate tears. Although further studies must be performed to provide conclusive evidence, our findings were consistent with our goals to provide a better, modern solution to an age-old debate between operative and nonoperative treatments of plantar plate tears. This unique case study was conducted by utilizing recent advancements in technology in hopes of challenging the current standard of care.


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Heel spoke wheel injuries in a community hospital in Togo

by Gamal AYOUBA PhD1*, Komla Séna AMOUZOU PhD2, Batarabadja BAKRIGA PhD3, Kouami AMAKOUTOU PhD4, Noufanague Kanfitine KOMBATE PhD5, Anani ABALO PhD2

The Foot and Ankle Online Journal 13 (2): 4

Motorcycles are one of the commonly used vehicles in our setting. Injuries caused by the wheels of the spokes to the heel engage the functional outcome of the foot and ankle. We aim to report the patterns of these injuries and the results of the treatment of such injuries in our community hospital. This prospective observational study included all cases with spoke wheel injury to the heel presenting between June 2014 to October 2018 in a community hospital in Kpalime, a city located northwest to the capital of Togo. Demographic and clinical data were collected from each patient including age, sex, occupation, injured side, and characteristics of the wounds. The wounds were grouped into those with Achilles tendon injury and those without Achilles tendon injury. The soft tissue injuries were classified according to Tscherne and Gotzen classification and managed accordingly. The AOFAS hindfoot score was used to assess the clinical outcome. Twenty-six patients were included, 13 females and 13 males. The mean age was 16 years (range 4-56 years). Seventeen patients were children (aged under 16 years). The right foot was affected in 21 patients and the left foot in 5 patients. The injury was classified as grade 2 (n=15) and grade 3 (n=11) of Tscherne and Gotzen. Wounds with Achilles tendon involvement accounted for 17 and without Achilles tendon accounted for 9. The mean time from injury to surgery was 18.4 hours (range 3-72 hours). Healing was achieved in 12 patients without complications. Complications included wound dehiscence (n=2), cutaneous necrosis and local infection (n=10), superficial infection (n=2). Secondary procedures performed were wound debridement (n=3) followed by skin graft (n=3), sural pedicled flap (n=2). The mean follow-up was 16.7 months (range 4-20 months). The average AOFAS score was 86.8 (range 64 – 100). The heel injuries are one of particularity of road traffic trauma in our setting. The outcome depends upon the involvement of Achilles tendon, an associated calcaneal fracture, and a high grade Tscherne and Gotzen classification.

Keywords: heel, spoke wheel, wounds, Achilles tendon, motorcycle, Africa

ISSN 1941-6806
doi: 10.3827/faoj.2020.1302.0004

1 – Department of orthopaedic and traumatology. Community Hospital of Kegue. University of Lomé. Togo
2 – Department of plastic and reconstructive surgery. University Hospital of Sylvanus Olympio. University of Lomé. Togo
3 – Department of orthopaedic and traumatology. University Hospital of Sylvanus Olympio. University of Lomé. Togo
4 – Department of orthopaedic surgery. University hospitals Cleveland Medical Center, Cleveland, Ohio, USA.
5 – Department of orthopaedic and traumatology. Hospital of Saint-Jean de Dieu d’Afagnan, Togo
* – Corresponding author:

Motorcycles are one of the most popular means of transportation in developing countries including sub-Sahara African countries such as Togo. Accidents associated with motorcycles are common among road traffic accidents in urban and rural areas in developing countries [1]. In Togo, during the first semester of 2019, motorcycles were involved in more than 51.36% of road traffic accidents [2]. The incidence of motorcycle spoke injuries to the heel has shown some specific features among road traffic accidents ranging from a simple laceration to a total traumatic foot amputation. [1,3-5]. Children make up a large proportion of the victims of these accidents [2]. The involvement of the Achilles tendon makes it a challenge for the orthopedic surgeons. In these cases, the exposure of the bony part of the Achilles tendon required a vascularized soft tissue resurfacing.

The main objective was to report data related to heel injuries and the secondary objectives of this study was to report patterns of the injury to the heel caused by spoke wheel, the management of these injuries, and the functional outcome.

Materials and Methods

This prospective study was carried out between June 2014 and October 2018 and included patients treated for motorcycle spoke injuries to the heel in the Department of Surgery at the community hospital of Kpalime, a city located 120km northwest from the capital of Togo in West Africa. The following demographic and clinical data of patients were recorded: gender, age, type of occupation, affected side, injury of Achilles tendon, associated injuries, number of surgical procedures and the course of treatment. We identified two groups of patients according to the clinical presentation of the wound: wounds with Achilles tendon involvement and wounds without Achilles tendon involvement. Soft tissue injuries were classified according to Tscherne and Gotzen [6] classification. Anteroposterior and lateral X-rays of the ankle were obtained in the Emergency Department. The functional outcomes were assessed using the AOFAS score (The American Orthopedic Foot and Ankle Score).


Clinical and socio-demographic characteristics

The study included 26 patients, 13 males and 13 females. The average age of the patients was 16 years (range, 4-56 years). Children (under 16 years old) accounted for 17, while adults (patients above 16 year-old) accounted for 9. All the adult patients were on the back seat and were wearing sandals at the time of the accident. As a mechanism of injury, the spokes of the wheel caught the heel of the patient just after the wheels had slipped over a bump of the road. The children were seated between their mother on the back seat and the rider of the motorcycle. Their feet were dangling and caught by wheel spoke. The wound was located on the vertical bony aspect of the heel or in some cases extended from the medial to lateral aspect of the heel. The wound was located on the posterior bony surface and extended 2 to 6 cm proximally in nine cases (Figure 1A), on the posteromedial aspect in 5 cases and on posterolateral (Figure 1B) aspect in 2 patients.

Figure 1 A: Posterior wound with complete section of Achilles tendon, B: Postero-lateral wound laceration, Achilles tendon partially sectioned, C: Semicircular laceration with Achilles tendon tearing and calcaneus fracture.

In the group with Achilles tendons involvement (17 patients): 7 had tendon tearing, 8 had complete section and 2 had partial section of the Achilles tendon. The wound of the heel was semi-circular in 10 patients (Figure 1C).

In 10 patients there were some associated injuries such as calcaneus fracture (5, 19%), tibia fibula third distal fracture (4, 15%), a particular calcaneus enucleation and one toes extensors tendons section. The demographic characteristics of the patients and the clinical presentations are reported in Table 1.

Treatment protocol

All patients received upon arrival in the emergency department, IV antibiotic (amoxicillin acid clavulanic 1g) and tetanus prophylaxis. The wounds were treated with abundant irrigation, drainage, and debridement. All sectioned Achilles tendons were sutured using the Kessler suture technique using non-absorbable suture. In a case of osseous disinsertion, the tendon was fixed to the calcaneal tubercle using a non-absorbable suture. The ankle was kept in a plantar flexion with circular POP for 3 weeks in all patients with Tscherne and Gotzen grade 3. In patients presenting with grade 2, an anterior POP slab maintained the ankle in a moderate plantar flexion for 10 days. In all cases, there was a window for the wound’s daily assessment during the first week (Figure 2) and until the wound is totally healed. In 4 patients tibial and or distal fibula fractures were associated with heel injury.

Figure 2 Window in the plaster contention for the wound assessment.

Figure 3 A: healing after skin graft, B: healing after sural pedicled flap.

The treatment of these fractures was a non-operative management using a long leg slab which was kept until wound healing. Then, the POP slab was replaced by circular contention. In a particular patient with calcaneus enucleation, after wound debridement a bone cement was used to fill the space. All patients received postoperatively the IV amoxicillin and clavulanic acid as antibiotic prophylaxis for 3 days. Rehabilitation began after removal of the splint in all patients. All adult patients were sent to physiotherapy for 2 consecutive weeks. Self-physiotherapy was established and encouraged in children.

Therapeutic Results

The average waiting time for surgery was 18.4 hours (range, 3-72 hours). The outcome after surgery at 3-weeks follow-up is summarized in Table 2. The healing of the wound was obtained in 12 patients (48%) without any complication.

Revision procedures were required in 14 patients. For a patient who had an enucleation of the calcaneus, the bone cement, which was put in during the index procedure, was removed after two weeks and then the wound was closed. The calcaneus space was filled with soft tissue. The Achilles tendon was fixed to soft tissues in a neutral position of the ankle. Table 3 summarizes the different revision procedures in the Tscherne and Gotzen grades.

The average duration of immobilization was 3.3 weeks (range, 3-6 weeks). The average healing time was 25 days (range to 20-49 days). The average length of stay in hospital was 10.3 days (range, 2-24 days). Postoperative complications included cutaneous necrosis in 13 patients, and superficial infection in 2 patients, Achilles tendon necrosis in one case. The long-term complications included an obvious disturbance in walking patterns in four cases, ankle instability in four cases, hindfoot varus of 6° in two cases. The flexion/extension range of motion of the ankle was between 15° and 30° in four cases. There were unsightly and retractile scars in eight cases. The mean follow-up (Figure 3) was 16.7 months (range, 4-20 months). The average AOFAS score was 86.8 (range, 64 – 100). The AOFAS score in patients who had Achilles tendon injury was 86.1 versus 88.2 for patients without Achilles tendon injury (p = 0.67).


The incidence of motorcycle spoke injuries to the heel has been increasing in developing countries especially in Africa and Asia [3,5,7]. In Nigeria an incidence of 4.26% has been reported among all road traffic trauma in a 10 years retrospective analysis published in 2017 by Agu TC [1]. These specific injuries occurring in the road traffic trauma affected mostly children [1,3,5,7] as confirmed in the current study. The overload of the motorcycle, inadequate footwear and sometimes bumpy roads are the main contributing factors to spoke injuries to the heel [2,4].

Our study, as well as past several studies, showed that motorcycle spoke injury is always unilateral, mostly confined to the right foot [3,4, 8]. This could be explained by the fact that the left foot is often protected by the motorcycle chain guard cover shield and therefore rarely injured.

Items N %
Sex Male 13 50
Female 13 50
Age Adult [>16 y] 9 35
Children [≤16 y] 17 65
Occupation Students 21 81
Farmers 4 15
Craftworker 1 4
Affected side Right 21 81
Left 5 19
Tscherne and Gotzen classification Grade 1 0
Grade 2 15 58
Grade 3 11 42
Achilles tendon involvement Without Achilles tendon involvement 9 35
With Achilles tendon involvement 17 65
Associated injuries None 15 58
Toes Extensors tendon section 1 4
Calcaneus fracture 5 19
Calcaneus enucleation 1 4
Tibia / fibula distal fracture 4 15

Table 1 Demographic and clinical data of the patients.

Grade Tscherne and Gotzen Healing Dehiscence of the wound Cutaneous necrosis Superficial infection Total
Grade 2 8 2 4 1 15
Grade 3 4 0 6 1 11
Total 12 2 10 2 26

Table 2 Three weeks postoperatively follow-up in the Tscherne and Gotzen grades.

Grade of Tscherne and Gotzen Healing by secondary intention Debridement + healing by secondary intention Skin graft Sural reverse pedicled flap Total
Grade 2 3 2 1 1 7
Grade 3 3 1 2 1 6
Total 6 3 3 2 14

Table 3 Second procedures according to the stage of Tscherne and Gotzen.

The shoe wearing could reduce the severity of the injuries, but the study of Naumeri et al. did not confirm this precaution [3]. The injuries are less severe (grade 0 and 1) in case of involvement of bicycle thus to low velocity of them [9]. But in our study the injuries were severe (grade 2 and 3) with extensive wound, degloving of the heel pad, and multiple associated injuries (tibia /fibula fractures, extensor tendon injuries, and a rare case of calcaneus extirpation). The injury can extend to all aspects of the heel in a semi-circular shape. In case of rupture of the Achilles tendon, the location could vary between 1 and 8 cm according to the different authors [4,10,11]. The severity of the soft tissue damages associating multiples injuries have been described by several authors [2,5,11]. This is a high velocity trauma due to wheel spokes, especially when riding at high speed. No main vascular pedicle was injured in our study. This complication has not been reported in the literature. There is no unanimous classification to describe motorcycle spoke injuries of the heel. Most authors used the classification of Tscherne and Gotzen. In our study, the treatment as well as the prognosis were evaluated using this classification. However, this classification gives little details about the fracture of the calcaneus, the rupture of the Achilles tendon and the other associated injuries.

The Grade 2 injuries required debridement and suturing of the wound without tension. The monitoring of the wound is important especially over 48 hours postoperative because secondary necrosis and sepsis are common at this step [3]. In some cases, in this study, patients initially classified grade 2 were managed secondarily for a reverse sural flap due to cutaneous necrosis. All grade 3 injuries in our study had Achilles tendon injury which was a partial or a complete rupture. The repair technique was similar to the common technique used in the literature [2,9]. Two sural pedicled flaps were performed because of secondary skin necrosis. This is the most common flap for the management of skin loss of the heel [3], [12,13]. Postoperative complications are common in motorcycle spoke injuries of the heel because of the extent of the injury and the population that is mostly affected [4,7,11].

The healing time and the duration of the hospital have not been reported to the grade of Tscherne and Gotzen. These parameters had been influenced by the complications in many patients requiring a secondary procedure. Also, Agu TC [1] found that the average duration of hospital stay was more than 3 weeks, and this depended on the degree of the injury. The major injuries including heel pad avulsions and ankle fractures stayed beyond 3 weeks in the hospital [1]. Naumeri and al [3] found that healing time was markedly increased in grade III injuries. Nevertheless, the global outcome was excellent in all patients on the AOFAS grading. However, there has been a better outcome (p=0.67) in the group of patients without Achilles tendon involvement compared to the group with Achilles tendon injuries. Only two patients that were poor had calcaneus enucleation (AOFAS=64) and Achilles tendon necrosis (AOFAS=65). In the patient with Achilles tendon necrosis, the infection and delayed treatment have hindered the reconstruction of the necrosed Achilles tendon leading to the poor result. In the second patient the loss of calcaneus had led to lack of heeling support with disturbance in walking pattern and loss of hind foot alignment which was 11° of valgus.

This excellent outcome due to the early presentation of the patients, the appropriate and timely care given, and the young ages of patients involved.


The heel injuries caused by motorcycle spoke wheels are a one of particularity of road traffic trauma in our setting. The difficulty to manage such patients starts with the difficulty to clinically assess the wound as no classification exists for such injuries, and to obtain reliable skin coverage. The high rate of complications works against patients that are part of the population that needed to stand for its daily food. The outcome depends upon the involvement of Achilles tendon, and a high grade of Tscherne and Gotzen and associated injuries such as calcaneus fracture. We had a satisfactory final outcome in mostly all of our patients. A dedicated team of orthopedic and plastic surgery could contribute to minimize the complications and expedite care, thus resulting in a faster return to work.

Funding declaration.

No funding to declare

Conflict of interest.

Authors declare that they have no competing interest in relation with this manuscript


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  13. Farooq U, Ishtiaq R, Mehr S, Ayub S, Chaudhry UH, Ashraf A. Effectiveness of Reverse Sural Artery Flap in the Management of Wheel Spoke Injuries of the Heel. Cureus: 2017;9[6]: 1-6. e1331.


Repair of Achilles tendon tear by unique hybrid technique

by RCS Khandelwal1, Jagdish Dhake2, Abhinav Jogani3*, Kishore Kumar4

The Foot and Ankle Online Journal 13 (2): 3

Achilles tendon rupture is a debilitating injury with a protracted and sometimes incomplete recovery. The surgical method of Achilles tendon repair, like open repair with or without augmentation, has a higher complication rate like delayed tendon healing (since paratenon integrity is destroyed in open repair technique which delays or hampers the tendon healing). Wound healing problems like suture granuloma, deep infection, skin edge necrosis, superficial dehiscence, pressure ulcer, and blisters may occur. Here we developed a newer hybrid technique (open exposures of the tendon and percutaneous tenodesis through calcaneum) for Achilles tendon repair to minimize the complications and enhance the tendon healing. Excellent results were observed with this hybrid technique.

Keywords: Achilles tendon tear, Achilles rupture, watershed, tendon augmentation

ISSN 1941-6806
doi: 10.3827/faoj.2020.1302.0003

1 – Professor & Head of Unit, Department of Orthopaedics, Seth GS Medical College and KEM Hospital, Mumbai, India
2 – Senior Registrar, Department of Orthopaedics, Seth GS Medical College and KEM Hospital
3 – Assistant Professor, Department of Orthopaedics, Seth GS Medical College and KEM Hospital
4 – Senior Registrar, Department of Orthopedics, Seth GS Medical College and KEM Hospital

* – Corresponding author:

The Achilles tendon is the most frequently ruptured tendon in the human body [1]. The mean age of presentation is 35 years with a male:female ratio of 20:1 [2,3].

The commonest site of rupture is in a region 3 to 6 cm above the calcaneus which corresponds to a watershed region of poor vascularisation[4]. Perfusion in this region is further compromised during stretching and contraction [5,6]. With increasing age there is decreased collagen-cross linking and weakening of the tensile strength of the tendon. Maffulli, et al., [7] and Järvinen, et al., [8] histologically observed significant collagen degeneration in patients with Achilles tendon rupture. Ruptured Achilles tendons have histologically demonstrated collagen degeneration with a greater content of collagen III and less collagen I [8].

Both oral and intratendinous injection of steroids have been implicated in spontaneous tendon rupture [9]. Other risk factors for rupture of the Achilles tendon include steroid therapy, hypercholesterolemia, gout, rheumatoid arthritis, long-term dialysis, and renal transplantation [10-14].

Surgical treatment, like the open repair technique, is associated with an increased incidence of postoperative complications, such as skin-tendon adhesions, infection, delayed healing of the surgical wound, sural nerve lesion, and suture granulomas [15].

Percutaneous repair, first described by Ma and Griffith [16], seems to bridge the gap by combining the advantages of both methods [17,18]. It is associated with a lower complication rate compared to open operative repair [15] but it may be associated with a higher risk of re-rupture and sural nerve injury [19]. However, several researchers have reported the absence of re-ruptures and nerve lesions [20].

Material and methods

A consecutive series of Achilles tendon rupture in 12 patients, occurring between 2 to 4 cm proximal to the calcaneus tuberosity, were treated by a hybrid technique (open exposures of the tendon and percutaneous tenodesis through the calcaneus). In all cases, the diagnosis was based mainly on history and clinical examination (functional impairments, palpation of the gap, and the Thompson test) and confirmed by ultrasound examination and MRI.  All patients were evaluated on follow-up.


The patient typically presents with pain, inability to bear weight and a history of a clear popping sensation or sound after an episode of activity during which they sustain a forced dorsiflexion of the ankle. The injury can also be sustained during eccentric contraction. The patient frequently describes the sensation of being kicked, shot or even bitten on the back of the heel. Acute Achilles tendon rupture can readily be detected on physical examination. Plantar flexion of the foot is understandably weak [16]. The Achilles tendon is best examined with the patient kneeling and the feet hanging over the edge of the chair. In this position, soft tissues hang off the Achilles tendon like a tent ridge pole and defects can be readily visualized (Figure 1). There is frequently a visible defect in the Achilles tendon. This is accompanied by swelling due to peritendinous hematoma.

Operative technique

The patient was placed in a prone position under general, spinal or peripheral nerve block anesthesia with the knees slightly flexed and a pneumatic tourniquet placed around the proximal part of the thigh. Before starting the procedure, the rupture and the diastasis (gap) were localized. The procedure is illustrated and described in detail in Figures 2-18.

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Figure 1 (patient in prone position) The left TA is ruptured. The right Achilles tendon is well defined and soft tissues hang off it like a tent. The suspension of the soft tissues off the Achilles tendon is not visible on the left side as the tendon is ruptured.

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Figure 2 Schematic diagram showing Kessler suture used in our Hybrid Technique.

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Figure 3 Preoperative MRI showing Achilles tendon tear.

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Figure 4 Patient placed in prone position on table.


Figure 5 Tunnel made by insertion of K-wire through the calcaneum for passage of ethibond suture.

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Figure 6 Preoperative incision markings along Achilles tendon with level of Achilles tendon rupture.

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Figure 7 Skin incision over Achilles tendon in midline.

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Figure 8 Ethibond suture passed through proximal tendon stump.


Figure 9 Ethibond passed vertically along the length of tendon from proximal to distal stump.


Figure 10 The Ethibond is then passed in a subcutaneous plane, taken out through the exit point of the tunnel.


Figure 11 The Ethibond is passed through a tunnel made by K-wire in calcaneus.


Figure 12 The Ethibond is passed in a subcutaneous plane, back into the incision site.


Figure 13 Ethibond passed along the length of the tendon from distal to proximal stump.


Figure 14 Final tightening of both ends of the Ethibond with foot in plantar flexion before making a knot.

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Figure 15 Arrow pointed over a knot made and buried subcutaneously with vicryl.

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Figure 16 Staple wound closure.


Figure 17 Postoperative follow-up after staple removal.


Figure 18 Postoperative MRI after two weeks.


The choice of suture material has important implications in tendon repair. Here we demonstrated excellent tendon healing results. Adverse surgical outcomes can be avoided by selection of the suitable suture materials for appropriate indication. Risks of Achilles tendon repair with open technique with or without augmentation include:

  • Excess bleeding
  • Nerve damage
  • Deep Infection
  • Blood clot
  • Wound healing problems like suture granuloma, skin edge necrosis, superficial dehiscence, pressure ulcer, blister.
  • Calf weakness


Hybrid technique (open exposures of the tendon and percutaneous tenodesis through calcaneus) of Achilles tendon repair with single ethibond suture has obtained better results in terms of tendon width , muscle mass and strength recovery of plantar flexion and patient satisfaction. As single Ethibond suture is used for tendon repair it decreases chances of postoperative infection. significantly good results were found in terms of clinical outcomes. Better outcomes found with Achilles Tendon Rupture Score.


  1. Maffulli N, Waterston SW, Squair J, Reaper J, Douglas AS. Changing incidence of Achilles tendon rupture in Scotland: a 15-year study. Clin J Sport Med. 1999;9:157–160.
  2. Möller A, Astron M, Westlin N. Increasing incidence of Achilles tendon rupture.  Acta Orthop Scand.  1996;67:479–481.
  3. Leppilahti J, Puranen J, Orava S. Incidence of Achilles tendon rupture. Acta Orthop Scand. 1996;67:277–279.
  4. Beddy P, Dunne R, de Blacam C. Achilles wiiitis. AJR Am J Roentgenol. 2009;192:W79.
  5. Carr AJ, Norris SH. The blood supply of the calcaneal tendon. J Bone Joint Surg Br. 1989;71:100–101.
  6. Komi PV, Fukashiro S, Järvinen M. Biomechanical loading of Achilles tendon during normal locomotion. Clin Sports Med. 1992;11:521–531.
  7. Maffulli N, Ewen SW, Waterston SW, Reaper J, Barrass V. Tenocytes from ruptured and tendinopathic achilles tendons produce greater quantities of type III collagen than tenocytes from normal achilles tendons. An in vitro model of human tendon healing. Am J Sports Med. 2000;28:499–505.
  8. Järvinen M, Józsa L, Kannus P, Järvinen TL, Kvist M, Leadbetter W. Histopathological findings in chronic tendon disorders. Scand J Med Sci Sports. 1997;7:86–95.
  9. Newnham DM, Douglas JG, Legge JS, Friend JA. Achilles tendon rupture: an underrated complication of corticosteroid treatment. Thorax. 1991;46:853–854.
  10. Lee WT, Collins JF. Ciprofloxacin associated bilateral achilles tendon rupture. Aust N Z J Med. 1992;22:500.
  11. Poon CC, Sundaram NA. Spontaneous bilateral Achilles tendon rupture associated with ciprofloxacin. Med J Aust. 1997;166:665.
  12. McGarvey WC, Singh D, Trevino SG. Partial Achilles tendon ruptures associated with fluoroquinolone antibiotics: a case report and literature review. Foot Ankle Int. 1996;17:496–498.
  13. Donck JB, Segaert MF, Vanrenterghem YF. Fluoroquinolones and Achilles tendinopathy in renal transplant recipients. Transplantation. 1994;58:736–737.
  14. West MB, Gow P. Ciprofloxacin, bilateral Achilles tendonitis and unilateral tendon rupture–a case report. N Z Med J. 1998;111:18–19.
  15. Chiodo CP, Wilson MG. Current concepts review: acute ruptures of the achilles tendon. Foot ankle Int [Internet] 2016 Sep 27;27(4):305–313.
  16.  Ma GW, Griffith TG. Percutaneous repair of acute closed ruptured achilles tendon: a new technique. Clin Orthop Relat Res [Internet] 2016. Sep 27, pp. 247–255.
  17. Maffulli N, Longo UG, Oliva F, Ronga M, Denaro V. Minimally Invasive Surgery of the Achilles Tendon. Orthop Clin North Am [Internet] 2017 Jul 15;40(4):491–498. 2009.
  18. McClelland D, Maffulli N. Percutaneous repair of ruptured Achilles tendon. J R Coll Surg Edinb [Internet] 2017 Jul 15;47(4):613–618.
  19. Wong J, Barrass V, Maffulli N. Quantitative review of operative and nonoperative management of achilles tendon ruptures. Am J Sports Med [Internet] 2016 Sep 27;30(4):565–575.
  20. Hockenbury RT, Johns JC. A biomechanical in vitro comparison of open versus percutaneous repair of tendon Achilles. Foot Ankle [Internet] 2016 Sep 27;11(2):67–72.


Bosworth fracture with proximal fibula entrapped within posterior pilon variant: A case report

by Sara Stachura, DPM1*; Edward J. Chesnutis III, DPM, AACFAS2; Melinda A. Bowlby, DPM, AACFAS3

The Foot and Ankle Online Journal 13 (2): 2

A Bosworth fracture is a rare injury that can result in an irreducible dislocation of the ankle joint. This case study presents a rare form of a Bosworth fracture in which the proximal portion of the fibula was entrapped within the posterior tubercle fracture of a pilon variant. It is important for physicians to be aware of rare variants of ankle fractures in order to diagnose and treat appropriately.

Keywords: Bosworth fracture, posterior malleolar fracture, irreducible trimalleolar fracture

ISSN 1941-6806
doi: 10.3827/faoj.2020.1302.0002

1 – 3rd Year Resident, Swedish Medical Center, Seattle, WA.
2 – Attending Surgeon, Swedish Medical Center, Seattle, WA; Private Practice, The Polyclinic, Seattle, WA
3 – Attending Surgeon, Swedish Medical Center, Seattle, W; Private Practice, The Ankle and Foot Clinic of Everett, Everett, WA
* – Corresponding author:

The Bosworth fracture is described as an irreducible ankle fracture-dislocation in which the proximal portion of the fibula is dislocated posterior to the posterior tubercle of the tibia. Though it has been described in the literature previously, it has become known as a Bosworth fracture due to a paper published in 1947 by Dr. David Bosworth, in which he described 5 patients in a case series. There have been over 60 cases reported since the original article [1].

It is reported in the literature that urgent surgery is required due to the irreducible nature of the Bosworth fracture by closed reduction. This is due to compromise of the soft tissue envelope seen with skin tenting from bone protrusion, neurovascular compromise, and compressive damage to talar and tibial cartilage [2]. The irreducibility has been attributed to an intact interosseous membrane holding the fibula posterior to the posterior tubercle [3].

Repeated attempts at closed reduction has been implicated in poor outcomes as well, causing increased damage to the soft tissue and articular cartilage [4].

There are multiple reasons that a fracture may resist closed reduction, the most common being interposition of soft tissue including the neurovascular bundle as well as the flexor tendons [2]. Fracture fragments may also become interposed in the joint, inhibiting motion [2]. Several variants have been described in the literature, including Bosworth fractures with an intact fibula, medial malleolar fractures, posterior tibial tubercle fractures, and deltoid ligament ruptures [3].

This case report presents a rare case of an irreducible trimalleolar ankle fracture with a Bosworth fracture, in which the proximal portion of the fibula was entrapped within the posterior malleolar fracture.

Figure 1 Pre-reduction radiographs.

Figure 2 Post-reduction radiographs.

Case Report

A 37-year old female with past medical history significant for obesity presented to the emergency department with right leg pain extending from the knee to the ankle. She had fallen off of an electric bike when she swerved to avoid a car one hour prior to presentation. The patient reported 10/10 pain and inability to bear weight. On physical exam, her right lower extremity was neurovascularly intact. There was ecchymosis noted to the ankle and mild edema consistent with a closed fracture dislocation. The foot appeared to be externally rotated. Even under conscious sedation, it was noted to be a difficult ankle reduction. Post reduction radiographs demonstrated improved alignment with the talus relocated beneath the tibia (Figure 2). A Computed Tomography (CT) Scan was ordered and surgery was scheduled. CT imaging revealed that the proximal portion of the fibula was dislocated behind the posterior lip of the tibia within the posterior tubercle fracture, inhibiting full reduction.

Figure 3 Preoperative CT demonstrating fibular entrapment within the posterior tubercle fracture.

The posterior tubercle fracture was noted to extend through the medial malleolus, with multiple comminuted fragments (Figure 3). There was another fracture noted at the tip of the medial malleolus. The injury appeared to be a supination external rotation type fracture, with blunt trauma from the talus and fibula resulting in a posterior pilon variant fracture.

Surgery was performed in a supine position. A lateral incision was made over the distal fibula. A large bone hook was used to wrap around the mid-portion of the fibula, and the fibula was successfully reduced into the incisura. Due to the degree of comminution, no interfragmentary screw was placed. A locking plate was utilized after fibular length was successfully restored. The posterior malleolus had been successfully reduced at this point. An anterior-to- posterior cannulated screw was advanced across the distal tibia, perpendicular to the fracture line. Next, a medial incision was made. The distal medial malleolar fracture fragment was noted to be comminuted and angled distal medial to proximal lateral, precluding the use of a hook plate. Cerclage wire was used in order to fixate this fracture fragment. A Hook test revealed significant gapping at the syndesmosis. A pelvic reduction clamp was used to reduce the syndesmosis and a fully threaded trans-syndesmotic screw was placed from the fibula into the tibia.

Figure 4 Postoperative radiograph one week status post open reduction with internal fixation. Cerclage wire noted to be broken.

The incisions were closed and the patient was placed in a posterior splint. She was discharged home with instructions to remain non-weight bearing to her right lower extremity.

The patient was examined regularly post-operatively (Figure 4). In accordance with pre-operative planning, the patient was taken back to the operating room approximately 8 weeks later and the syndesmotic screw was removed and replaced with a non-absorbable suture button device. By 12 weeks postoperatively the patient was walking in a CAM walker with minimal pain and undergoing physical therapy.


Bosworth fractures are uncommon amongst ankle fractures, with one study reporting 51 out of 3,140 patients, or 1.62% [5]. This is the only prevalence study that has been performed due to the rarity of this fracture pattern.

Figure 5 Postoperative radiographs one week status post syndesmotic screw replacement with tightrope.

There are many variants, associated injuries, and complications reported with the Bosworth fracture, including dislocation with an intact fibula, rupture of the deltoid ligament, medial malleolar fracture, posterior tibial tubercle fracture, increased risk of compartment syndrome, avascular necrosis of the talus, osteoarthritis of the ankle, neurovascular injury, joint stiffness, osteochondral lesions, skin necrosis, and wound infection [3-5].

Radiographic signs of a Bosworth fracture include widening of the medial joint space, posterior displacement of the fibula on lateral radiographs, and overlap of the proximal fibular fracture fragment with the distal tibia on the anteroposterior view [4]. Unfortunately, these signs can all be interpreted as poor radiographic technique in terms of positioning [1]. It has been proposed that external oblique radiographs may be a useful tool to diagnose this injury by measuring the displacement of the fibular shaft [6]. The “axilla sign” has also been described, resulting from the internal rotation of the tibia when the fibula is posterior dislocated. It appears on the mortise view at the medial tibial plafond as a cortical radiodensity [7].

There has been conflicting data in the literature in regards to timing of surgery and outcome. One study of 15 patients with Bosworth fractures found that patients who underwent surgical open reduction and internal fixation within 24 hours had better functional outcomes. In addition, this study showed that intermediate-term clinical outcomes were comparable between Bosworth fractures and other ankle fracture dislocation types [4].

Aggressive attempts at closed reduction are not advised due to the possibility of increasing trauma to the fibula, cartilage, and surrounding soft tissues [5]. One study found poorer clinical outcomes associated with multiple attempts at closed reduction [4]. Due to the difficulty of diagnosis on radiographs, general belief that early surgical intervention leads to better outcomes, and poorer outcomes in regard to multiple closed reduction attempts, it is important for physicians to have a high index of suspicion for fracture dislocations resisting reduction and low threshold for CT imaging.

In terms of surgical approach, a lateral incision was made over the fibula in order to reduce the fracture. Although adequate, a posterolateral approach may have allowed more exposure of the deformity for evaluation and correction.

One cadaveric study reported a mechanism for the Bosworth fracture, noting that the mechanism is external rotation on a supinating foot. Stage one and two involve the fibula being posteriorly dislocated out of the fibular notch with rupture of the anterior and posterior tibiofibular ligaments, respectively. In stage three, the anterior medial ankle joint capsule ruptures. Stage four involved tearing of the interosseous membrane, followed by entrapment of the fibula posterior to the tibia in stage five. Finally, further rotation of the talus results in an oblique fracture of the fibula in stage six, and deltoid rupture or medial malleolus fracture in stage seven [8].

There is one other reported case of a Bosworth fracture with the proximal fibular fracture fragment dislocated within the posterior tubercle portion of a pilon fracture [9]. This has been predicted to be a rare form of injury due to the nature of pilon fractures. There is often comminution of the posterior tubercle which can include fracture of the posterior lip of the fibular groove, precluding the possibility of the proximal fibula becoming trapped behind the posterior lip and between large fracture fragments [1].


This case study presented a rare form of Bosworth fracture in which the proximal portion of the fibula was entrapped within the posterior tubercle of a trimalleolar ankle fracture dislocation. It is important for physicians to be aware of rare variants and have a high index of suspicion in ankle fractures that are difficult to reduce in order to diagnose and treat appropriately. Further imaging should be performed to evaluate the deformity, as this form of ankle fracture is easily identified with a CT scan. In these cases, surgery should be strongly considered due to the poor prognosis with conservative treatment.

Funding declaration: None

Conflict of interest declaration: None


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  2. Schepers T, Hagenaars T, Den Hartog D. An irreducible ankle fracture dislocation: the Bosworth injury. J Foot Ankle Surg 2012 Jul-Aug; 51(4):501-503.
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  5. Won Y, Lee GS, Hwang MJ, Park IY, Song JH, Kang C, Hwang DS. Improved functional outcome after early reduction in Bosworth fracture-dislocation. Foot Ankle Surg 2018 Nov;S1268-7731(18)30300-X.
  6. Yang KH, Won Y, Lim JR, Kang DH. Assessment of Bosworth-type fracture by external oblique radiographs. Am J of Emerg Med 2014 Nov;32(11):1387-1390.
  7. Khan F, Borton D. A constant radiological sign in Bosworth’s fractures: “the Axilla sign”. Foot Ankle Int 2008 Jan;29(1):55-57.
  8. Perry CR, Rice S, Rao A, Burdge R. Posterior fracture-dislocation of the distal part of the fibula. Mechanism and staging of injury. J Bone Joint Surg Am 1983 Oct;65(8):1149-1157.
  9. Cappuccio M, Leonetti D, Di Matteo B, Tigani D. An uncommon case of irreducible ankle fracture-dislocation: the “Bosworth-like” tibio-fibular fracture. Foot Ankle Surg 2017 Mar;23(1):e1-e4.

Lower extremity neurological complication following routine surgical intervention

by Dr. Christina Sigur Long1, Dr. Michael McCann1*

The Foot and Ankle Online Journal 13 (2): 1

Pneumatic tourniquets have been utilized for centuries to assist in hemostasis, resulting in faster operating times and better identification of anatomical structures. Mortality and morbidity are rare but can be associated with improper tourniquet use.  This case study reports on a lower extremity neuropathy that developed after seemingly proper pneumatic tourniquet use during ankle surgery. Nerve conduction velocity (NCV) testing suggested likely etiology was from a resolved compartment syndrome. 

Keywords: compartment syndrome, tourniquet, neurapraxia

ISSN 1941-6806
doi: 10.3827/faoj.2020.1302.0001

1 – Wake Forest Baptist Health, 1 Medical Center Blvd, Winston-Salem, NC 27157
* – Corresponding author:

The U.S. Food and Drug Administration recognizes the pneumatic tourniquet as a Class-I medical device indicating minimal harm to the patient with routine use [1]. When properly utilized, tourniquet application creates a bloodless surgical field enhancing the surgeon’s ability to identify anatomic structures and reduce intraoperative blood loss [1]. Its roots can be traced back to the Roman Empire (199 BCE – 500 CE), when bronze and leather devices were donned to injured extremities to reduce bleeding during war-time amputations [1]. In 1864, Joseph Lister was the first surgeon to apply a tourniquet in the operating room [1]. Harvey Cushing introduced the pneumatic tourniquet in 1904 allowing tourniquet pressure to be manually controlled which aided in decreasing associated injuries. It has been estimated that over 15,000 surgical procedures occur daily which require the use of a pneumatic tourniquet [1]. Routine tourniquet use is not without risk of morbidity or even mortality with potential complications including compression neurapraxia, compartment syndrome, wound infection, wound hematoma, delayed recovery of muscle power, arterial hypertension, cardiorespiratory decompensation, rhabdomyolysis, and cardiorespiratory decompensation [2]. The rate of nerve injury associated with tourniquet use ranges from 0.1% – 7.7% [3]. To assist in decreasing comorbidities and mortality related to tourniquet use, numerous studies have been conducted to determine appropriate tourniquet applications, tourniquet duration, tourniquet design, and patient selection when utilizing tourniquets [1]. This Case Study reports a patient developing a common fibular neuralgia after routine use of high calf tourniquet during routine ankle surgery.

Case Report

A 48 year-old healthy female presents to the clinic complaining of chronic right ankle pain and weakness after an ankle sprain one year prior. She underwent a two-year period of conservative treatment with no resolution of her symptoms.  MRI obtained showed tendinosis and possible tearing of her peroneal tendons. 

Surgical intervention was deemed necessary based on progression and chronicity of her symptoms with failure and exhaustion of conservative treatment.

The patient received a preoperative popliteal fossa and saphenous nerve block and was placed in the supine position with a pneumatic calf tourniquet set to 250 mmHg. A semi-linear incision was made along the course of the peroneal tendons.  Dissection carried down to the peroneal tendons with further evaluation, identifying an intrasubstance tear of the peroneus brevis tendon. The tendon was debrided and re-tubularized in the usual manner. The foot was then everted to re-approximate the superior retinaculum. The surgical incision was closed and dressed in the usual manner. The pneumatic tourniquet was deflated at 68 minutes. Proper hyperemic response was noted. A modified Jones compression posterior splint was applied with the foot slightly everted and ankle at 90 degrees. She was discharged from PACU with all vitals stable and vascular status intact to the right lower extremity.   Postoperative instructions were given to remain non-weight bearing to her right lower extremity. 

The first postoperative visit occurred ten days following her procedure without any notable complications. Pain level was tolerable and no complications involving falls were noted.  She was transferred into a removable CAM boot at this time, continuing non-weight bearing status to the right lower extremity.  At 3 weeks post-procedure, she complained of acute onset of pain, numbness, and paresthesia in her right lower extremity, from knee to foot, which worsened at night but was constant. Based upon clinical symptoms, a diagnosis of neuralgia was made.  Treatment began with oral Gabapentin 300 mg taken nightly.  Physical therapy was initiated 1 week later. At 6 weeks, the patient continued to have numbness and paresthesia to the entire right foot and up to her knee.  Patient denied any help from the Gabapentin medication.  Physical exam revealed decreased muscle strength and a hyper-sensitivity to light touch to her right foot and lower leg. Physical therapy helped with recovery of her tendon repair but no change to her neurological symptoms was noted.  Patient was sent to pain management and complex regional pain syndrome was ruled out.  She tried and failed Elavil oral medication. She was intolerant to Cymbalta oral medication.  Nerve conduction velocity and EMG studies were obtained approximately 14 weeks following surgery to assess for potential areas of nerve entrapment or injury. Results revealed a mild polyneuropathy affecting sensory and motor nerves without evidence of a localized neuropathy such as a tarsal tunnel syndrome or focal sensory neuropathy. The study suggested small nerve fibers may have been affected and a resolved compartment syndrome was deemed as a likely etiology of the polyneuropathy. At 5 months, the patient showed recovery from her peroneal tendon surgery but still with continued paresthesia and numbness to the right foot and ankle, up to the knee.  The pain at this point is tolerable with shoe and activity modifications.  


Complications arising after tourniquet use during lower extremity surgical procedures are rare but still occur. A questionnaire survey in Norway estimated neurological complications associated with lower extremity tourniquet use occurred in one per 3752 applications [4]. Our case study reports neurological complication occurring secondary to a possible compartment syndrome that occurred 3 weeks after the surgical procedure. Compartment syndrome is a potentially serious complication which can occur once interstitial pressure in a closed fascial compartment increases to a level which impedes vascular flow resulting in myoneuronal function impairment and soft tissue necrosis [5]. Normal compartment pressures allowing capillary perfusion are described ranging from 0 to 8 mmHg [6]. Once interstitial pressure increases above this range, blood flow is impaired leading to the associated complications [6]. Previous case studies have reported compartment syndrome occurring after tourniquet use [5,7,8]. but in our case study the clinical presentation of compartment syndrome was not present directly following surgery. Classic presentation of compartment syndrome has been described as pain out of proportion, pain on passive stretching of the affected compartment with associated clinical symptoms of pallor, pulselessness, and paresthesia of the affected extremity [5]. Compartment syndrome resulting after lower extremity tourniquet application has been reported to occur after prolonged ischemia time with reperfusion edema, direct muscle trauma secondary to repeated inflations of the tourniquet and improper positioning [9]. As described per the surgical report, the patient was appropriately positioned on the operating table, with proper application, location, and duration of a pneumatic tourniquet and without repeated inflations. This patient did obtain regional anesthesia via a popliteal fossa and saphenous nerve block which some suggest can delay the diagnosis of compartment syndrome [10].

Pain is a cardinal feature of compartment syndrome which theoretically can be altered by analgesia. Our patient did not begin to experience pain until approximately 3 weeks following her surgical procedure. Mar, et al., reported 32 of 35 patients who received epidural analgesia had “classic signs” of compartment syndrome which included pain out of proportion. Their conclusion stated there was no convincing evidence regional analgesia delays the diagnosis of compartment syndrome [10].  

Peripheral nerves are composed and organized into connective tissue structures forming a framework to provide protection and function to nerve fibers. These connective tissue structures include the endoneurium, perineurium, and epineurium. Individual nerve fibers are surrounded by the endoneurium. Fascicles, groups of endoneurium, are enveloped by the perineurium. Epineurium encases bundles of fascicles [11]. Vessels in the epineurium are more vulnerable to compression trauma resulting in permeability changes compared to endoneurium vessels. Vessel permeability changes occurring secondary to trauma lead to associated edema formation and accumulation.  Endoneurium edema is prevented from draining into adjacent areas due to a blood-nerve-barrier and a lack of lymphatic channels. Perineurium edema is prevented from draining into adjacent areas due to a selective diffusion barrier. Past studies have suggested edema accumulation inside nerve fascicles create a “miniature compartment syndrome” which could alter nerve function [12]. A miniature compartment syndrome may affect or impair nerve function through a sustained increase in fascicle pressure, altering endoneurium fluid electrolyte composition or reducing blood flow to nerve segments.

Ochoa, et al., demonstrated nerves directly beneath and near the tourniquet cuff edge were subjected to injury due to external compression. This direct pressure has been shown to cause displacement of Nodes of Ranvier and myelin sheath invagination which disrupts nerve conduction [13]. The resulting damage associated with displacement of Nodes of Ranvier and myelin sheath invagination is associated with partial or complete local conduction block which is usually reversible within weeks or months. Nodes of Ranvier are essential components of nerve function and are located along peripheral nerve axons to increase conduction velocities [14]. Compression from tourniquet application has been shown to displace Nodes of Ranvier up to 300 nanometers from their original site [13]. Tourniquet induced compression can affect larger nerve fibers responsible for motor function or smaller nerve fibers responsible for pain, temperature and autonomic function. 

Our case study reports a polyneuropathy affecting motor and sensory nerves with a likely etiology of a resolved compartment syndrome. Clinical presentation of classic compartment syndrome was not present during this patient’s immediate postoperative period. Nerve injury resulting in the polyneuropathy most likely was secondary to nerve injury sustained from external compression via a pneumatic tourniquet. As discussed, nerve function can be altered from an increase in fascicle pressure secondary to edema accumulation or displacement of essential nerve components required for normal nerve function. 

If the patient experiences nerve related injuries after surgery, proper evaluation and a thorough work-up is warranted to determine the severity of injury. To determine the severity of the lesion, a nerve conduction study can be utilized to confirm the lesion grade. Seddon, et al., classified nerve injuries into three grades, neuropraxia, axonotmesis, and neurotmesis based on the severity of lesion [16]. Sunderland later expanded this classification into five different nerve injury patterns.  Neurapraxia, Grade 1, is the mildest injury and produces a local nerve conduction block at the site of injury with normal nerve conduction proximal and distal to injury. There is no associated injury to the surrounding nerve tissues. Axonotmesis, Grade 2, is seen when demyelination occurs at the injured site leading to Wallerian degeneration distal to the demyelinated segment [17]. Nerve regeneration is possible due to the preserved endoneurium and perineurium.  If full functional recovery of the nerve occurs within 3 months after the injury it is classified as a neurapraxia but if recovery occurs at a rate of one inch per month the injury is classified as axonotmesis. Fibrillations and denervation potentials can be seen distal to the site 3 weeks following the injury. Recovery is spontaneous and complete with axonotmesis injuries but can take weeks to years [18]. Damage to the endoneurium without damage to the epineurium is seen in grade 3 injuries. Damage to the myelin, endoneurium, perineurium, and axon indicates a Grade 4 injury. Grade 5 injuries are seen with complete transection of the nerve [17].

Nerve-related injuries during surgery can create a complex postoperative course. If questionable nerve symptoms do occur, proper work up is warranted to determine diagnosis and severity of the damage. Treatments range from oral and topical medications to surgical neurolysis. This case study shows our patient developing polyneuropathy 3 weeks after seemingly proper surgical use of calf tourniquet, likely from a resolving compartment syndrome after surgical use of tourniquet.  If a patient displays the appropriate symptoms, a high suspicion for compartment syndrome is warranted.  

Funding declaration

Acknowledgment that the authors did not receive any funding from any sources

Conflict of interest declaration

The authors whose names are listed certify that they have no affiliations with or involvement in any organization or entity with any financial interest.


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The influence of great toe valgus on pronation and frontal plane knee motion during running

by Richard Stoneham PhD1, Gillian Barry PhD1, Lee Saxby BSc2, Mick Wilkinson PhD1*

The Foot and Ankle Online Journal 13 (1): 7

Injury rates in running range from 19.4‐79.3%, with injuries at the knee comprising 42.1%. Pronation and altered frontal plane knee joint range of motion have been linked to such injuries. The influence of foot structure on pronation and knee kinematics has not been examined in running. This study examined associations between great toe valgus angle, peak pronation angle and frontal plane range of movement at the knee joint during overground running while barefoot. Great toe valgus angle while standing, and peak pronation angle and frontal plane range of motion of the dominant leg during stance while running barefoot on an indoor track were recorded in fifteen recreational runners. There was a large, negative association between great toe valgus angle and peak pronation angle (r = -0.52, p = 0.04), and a strong positive association between great toe valgus angle and frontal plane range of motion at the knee joint (r = 0.67, p = 0.006). The results suggest that great toe position plays an important role in foot stability and upstream knee-joint motion. The role of forefoot structure as a factor for knee-joint injury has received little attention and could be a fruitful line of enquiry in the exploration of factors underpinning running-related knee injuries.

Keywords: great toe valgus, pronation, frontal plane knee range of motion, running

ISSN 1941-6806
doi: 10.3827/faoj.2018.1301.0007

1 – Department of Sport, Exercise and Rehabilitation, Northumbria University, UK
2 –, Suffolk House, Louth, Lincolnshire, UK
* – Corresponding author:

Injury incidence in running ranges from 19.4‐79.3% [1, 2]. The knee is the most injured site, comprising 42.1% of all running‐related injuries [2, 3]. Patellofemoral Pain Syndrome (PFPS) is the most common running‐related knee injury, followed closely by Iliotibial Band Syndrome (ITBS) [3].  Altered frontal plane hip and knee joint kinematics and pronation during the stance phase of running have been linked to these injury types, and differentiate injured from uninjured runners [4-6]. Knee abduction, femoral internal rotation, tibial external rotation, and foot pronation, have been theoretically linked to injury in a population of patients with PFPS [7]. As such, interventions to normalise altered frontal plane kinematics during running might be valuable for rehabilitation of this type of knee injury. Interventions have tended to focus on proximal areas linked to altered knee kinematics. However, training studies to increase hip abduction and external rotation strength have not decreased hip or knee frontal plane peak joint angles or joint excursions during the stance phase of running [8-10]. Moreover, associations between hip strength and frontal plane hip and knee peak angles and joint excursions while running and jumping are weak [9, 11]. These findings suggest that proximally-based interventions are not effective at altering lower extremity running mechanics and risk of running related injury. Studies exploring the distal end of the kinetic chain have utilised barefoot and minimal footwear, and hip and foot muscle strengthening interventions to reduce surrogate measures associated with injury at the knee and other sites [10, 12-14]. Injury rates, however, remain high [15]. The influence of foot structure on pronation and knee joint kinematics in running has, by contrast, received little attention.

Data comparing foot structure in habitually-barefoot and habitually-shod populations have reported consistent differences in the spread/abduction of the great toe from the other toes [16-19]. Based on Newtonian physics, larger areas of support provide greater stability. It has been suggested that an abducted great toe position might be important for controlling the direction of body weight during running, secondary to improved stability of the foot [20, 21]. Running is essentially a series of alternate single-leg jumps, where multiples of bodyweight must be supported and controlled using a spring-like action of the supporting foot and limb [22, 23]. Early research showed an active role of the toes, the great toe in particular, from midstance to toe off in running [24]. More recent data comparing habitually barefoot to habitually shod populations suggested that the abducted great toe position, characteristic of the barefoot group, reduced peak forefoot pressures during running by increasing the area of support [19]. Another comparative study from the same lab [25] found larger ankle eversion and internal rotation (which together comprise pronation) during the landing phase of jumping in habitually shod compared to habitually-barefoot participants, attributing differences to the abducted great toe position characteristic of the barefoot group. Together, these studies suggest a link between great toe position and foot and ankle stability in running, and dynamic tasks with similar demands to running. Given evidence of the link between pronation, altered frontal plane motion at the knee joint and risk of knee injury [7], there is a possible mechanistic link between great toe position, pronation and frontal plane knee joint kinematics.

Previous research suggests that the toes have a stabilising function, and that great toe position influences area of support in running, and the extent of pronation in the landing phase of jumping. The influence of great toe position on pronation and on kinematics at the knee joint has not been examined in running. The aim of this study was to examine associations between great toe valgus angle, peak pronation angle and frontal plane range of movement at the knee joint during overground running while barefoot, the latter being necessary to avoid toe position being constrained by shoes.



With institutional ethics approval, 15 volunteers (ten male, five female) participated. Mean and SD age, stature and mass of all participants were 26±7 yrs, 1.71±0.01 m and 69±10.9 kg respectively. Inclusion criteria were aged 18-45 years and participation in endurance running more than once per week as part of habitual-exercise regimes, with at least one run longer than 30 minutes. Participants were excluded if they had an injury to the lower limbs in the previous six months, or any condition that could affect their normal running gait.


An observational design assessed the relationship between great toe valgus angle relative to the first metatarsal, peak pronation angle and frontal plane range of movement at the knee joint of the dominant leg during stance, while running barefoot on an indoor runway. The barefoot condition was chosen as it was the only way to ensure that the toe angle recorded in standing was not altered by footwear while running. Data were collected in a single visit. Participants were provided with a short-sleeved compression top and shorts to improve skeletal representation in biomechanical modelling, and were instructed to be well rested before testing. Reflective markers were attached in ‘Plug-In gait’ and ‘Oxford-Foot Model’ formations to assess lower-limb kinematics of the dominant limb. Participants were habituated to running barefoot with a 30-minute, self-paced run. After habituation, participants ran over a 20-m runway where kinematic data were captured by 14 optoelectronic cameras. Electronic timing gates (Brower timing gates, Utah, USA) placed in the data capture area (2.7m apart) were used to record speed in each trial. The average running speed was 2.48±0.38 m·s-1.


Great toe valgus angle

Participants stood barefoot on top of a 0.35-m high platform covered in graph paper. The non-dominant foot was placed on the platform first, aligning the most posterior aspect with a horizontal reference line on the graph paper. The dominant foot was positioned next, shoulder width apart from the other foot, and with the most posterior aspect on the same horizontal reference line. The first metatarsal proximal-and distal-dorsal protrusions, and the central and dorsal point of the interphalangeal joint of the great toe were identified by palpation, and marked using a permanent pen. A digital camera (CX240, Sony, Japan) positioned 0.3m above the platform on a tripod was aligned with the first metatarsophalangeal joint, and the zoom was adjusted so that bony prominences defining great toe angle were visible. A still image was captured and saved for analysis of great toe valgus angle.


Prior to habituation, anthropometric measures were recorded for use in biomechanical modelling (stature (mm), mass (kg), bilateral-leg length (mm), and knee and ankle joint width (mm)). For assessment of lower-limb joint kinematics, participants had a series of markers (Ø=14mm) attached in ‘Plug-In gait’ and ‘Oxford-Foot Model’ formations. Anatomical locations of the ‘Plug-In gait’ and ‘Oxford-Foot Model’ were sacrum, bilateral anterior-and posterior-superior iliac spines, the bilateral distal-lateral thigh, bilateral femoral-lateral epicondyle, the bilateral distal-lateral lower-leg, the bilateral lateral malleoli, the left/right toe (dorsal aspect of the second metatarsal head) and the calcaneus of the non-dominant limb at the same height as the toe marker. The following markers were placed on the dominant limb only, lateral head of the fibula, tibial tuberosity, anterior aspect of the shin, the medial malleoli, the proximal aspect of the calcaneus, a ‘peg marker’ extending from the most posterior aspect of the calcaneus, the inferior aspect of the calcaneus, sustentaculum tali, proximal and dorsal aspect of the first metatarsal head, the medial and distal aspect of the first metatarsal head, the proximal-and distal-lateral aspects of the fifth metatarsal and the medial aspect of the first phalanx. Fourteen infrared-optoelectronic cameras (Vicon 10 xT20 and 2 x T40, Oxford, UK) captured kinematic trajectories at 200Hz. 

Data treatment

A trial was deemed successful when running speed was ± 5% of the predetermined running speed from the habituation run. Dominant limb data for peak pronation angle and frontal plane range of motion at the knee joint were exported to Microsoft Excel (Microsoft, USA). Foot structure images were loaded to Dartfish ClassroomPlus (version 7.0, Fribourg, Switzerland) where great toe valgus angle was measured using the angle tool. (Chicago, USA).

Statistical analysis

Statistical analysis was undertaken using JASP 0.10.2. Following verification of assumptions of linearity and uniformity of errors using Q-Q and residuals versus predicted value plots respectively, linear regression assessed associations between great toe valgus angle, peak pronation angle and frontal plane range of motion at the knee joint. Strength of associations were judged against Cohen’s effect size categories for Pearson’s  r i.e. small association 0.1-0.3; moderate association 0.3-0.5; large association 0.5-1.0 [26]   Significance was accepted at p < 0.05.


Mean and SD great toe valgus angle, peak pronation angle and frontal plane knee range of motion were 9.5±6.1°, -5.2±6.6° and 6.2±2.2° respectively.

Association between great toe valgus and peak pronation angle.

There was a large, negative association of great toe valgus angle and peak pronation angle during stance (r = -0.52, p = 0.04). As great toe valgus angle increased (more positive = more valgus), peak pronation angle decreased (more negative = increased pronation) (see Figure 1). The regression equation showed a 0.59° increase in peak pronation for every additional degree of great toe valgus (95% CI 0.01 to 1.12°).

Figure 1 Association between great toe valgus angle and peak pronation angle during overground barefoot running on an indoor track in 15 recreational runners.

Association between great toe valgus and frontal plane knee range of motion.

Great toe valgus angle was strongly and positively associated with frontal plane range of motion at the knee joint (r = 0.67, p = 0.006). As great toe valgus angle increased, frontal plane knee range of motion also increased (see Figure 2). The regression equation showed a 0.24° increase in frontal plane knee joint excursion for every one degree increase in great toe valgus angle (95% CI 0.01 to 0.40°).

Figure 2 Association between great toe valgus angle and frontal plane range of motion at the knee joint during overground barefoot running on an indoor track in 15 recreational runners.


The aim of this study was to examine associations between great toe valgus, peak pronation and frontal plane range of motion at the knee joint during overground running. There was a strong, negative correlation between great toe valgus angle and peak pronation such that increased great toe valgus was associated with a more negative peak pronation angle (increased pronation). There was also a strong, positive correlation between great toe valgus angle and frontal plane range of motion at the knee joint such that increased great toe valgus was associated with larger knee joint excursions in the frontal plane. Altered frontal plane hip and knee joint kinematics and pronation during the stance phase of running have been linked to running-related knee injury, and can differentiate injured from uninjured runners [4-6]. Knee abduction and foot pronation have also been theoretically linked to patellofemoral pain [7]. In light of this evidence, our results suggest that forefoot structure might be an important but largely unexplored factor in running-related knee injury.

As this is the first study to explore the association between great toe valgus, pronation and frontal plane knee joint excursions during running, there are no studies with a similar approach for comparison. Nevertheless, the strong relationships observed broadly support findings from previous comparative cross-sectional studies of habitually barefoot and habitually shod participants that differed in forefoot structure with respect to the spread/abduction of the great toe [19, 25]. Shu et al. [25] observed larger ankle eversion and internal rotation (which together comprise pronation) in habitually shod compared to habitually barefoot participants in the landing phase of jumping. As running is essentially a series of single-leg jumps, the strong association of great toe valgus angle with peak pronation observed in running in our study is not surprising. The reduced and more evenly distributed forefoot peak pressures of habitually barefoot participants reported by Mei et al. [19] alludes to greater forefoot stability during the period of stance when forces are highest. It is possible that as the stability provided by the great toe decreases with increasing valgus angle, instability of the foot could manifest as higher peak pronation. Increased forefoot instability with increased great toe valgus is a plausible mechanism that could explain the strong correlation of great toe valgus angle and peak pronation that we observed. Increased postural instability with great toe valgus [27] and with splinting of the great toe into flexion [28] have been observed in single-leg balance tasks. Though these studies examined static balance and not the dynamic single-leg balance characteristic of running, the underpinning link between the area of the base of support and subsequent stability could be assumed to be common to both. Instability at the foot could have kinematic consequences further up the kinetic chain, resulting in increased frontal plane motion at the knee. The strong, positive association of great toe valgus angle with frontal plane knee joint excursion observed in the current study is consistent with this suggestion. Moreover, the kinematic links between pronation and frontal plane knee joint range, as well as the link between these factors and running-related knee injury suggested here have been suggested previously elsewhere [7] and supported by previous studies [4-6].

The main limitation of this study is that the correlational design prevents any suggestion of a causal link between great toe valgus, peak pronation and frontal plane knee joint excursions. Another limitation is that great toe valgus angle was measured during static stance, not while running, so an assumption that valgus angle remains relatively unchanged when the foot is loaded during running is implicit in the interpretation of the results. Previous research, however, suffers from similar limitations, comprising only comparative studies of foot and ankle function and pressure distributions of groups with mean abducted versus mean valgus great toe positions. As such, a correlational study like this one does add to the understanding of how foot structure might relate to pronation and knee joint kinematics in dynamic tasks like running by examining a ‘dose-response’ type association, in addition to the ‘with and without’ type evidence of previous comparative studies. Moreover, there are plausible mechanisms of action for both key findings in this study, so the data provide both direct and mechanistic evidence towards establishing a causal link [29]. A logical next step for this area of research would be randomised control trials where pronation and knee kinematics are evaluated before and after an intervention to alter great toe valgus angle in one group, with the control group foot structure remaining unchanged. Interventions could potentially include corrective surgery or corrective devices that reposition the great toe. Additional comparative studies that measure knee joint kinematics during running would, however, be a useful intermediate step.

In summary, this study observed strong associations between great toe position, peak pronation and frontal plane range of motion at the knee joint during over-ground barefoot running. The results suggest that great toe position plays an important role in foot stability and subsequent knee-joint motion. Both pronation and frontal plane knee-joint motion have been implicated in the etiology of knee injuries. The role of forefoot structure as a factor for knee-joint injury has received little attention and could be a fruitful line of enquiry in the exploration of factors underpinning running-related injuries.

This study formed part of a PhD program collaboratively funded by Northumbria University and VivoBarefoot. VivoBarefoot had no input to the design, analysis or interpretation of studies or data, or the preparation of this manuscript.


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Case study of idiopathic degeneration of the talonavicular joint

by Ryan Allen, DPM1*; William Arthur, DPM1; Christina Ma, BS2; Charles Parks, DPM, FACFAS3; Monara Dini, DPM, FACFAS3

The differential diagnosis for chronic pain out of proportion is broad, and a final diagnosis of Mueller-Weiss syndrome is often a diagnosis of exclusion. We present a patient who experienced pain out of proportion following minor trauma. This progressed into worsening pain that affected his day-to-day activities and ability to perform work. Eventually, there was destruction of his talonavicular joint and early stages of idiopathic fusion. Multiple specialties were involved in this case including infectious disease, rheumatology, and neurology. Excluded diagnoses were septic joint, osteomyelitis, complex regional pain syndrome, Charcot arthropathy, and rheumatoid arthritis. We present a rare case of a patient who experienced idiopathic destruction and fusion of his talonavicular joint following minor trauma, with Mueller-Weiss syndrome suspected. The patient would make significant recovery following arthrodesis of the talonavicular joint.

Keywords: Mueller-Weiss-syndrome, complex regional pain syndrome, idiopathic fusion, talonavicular joint

ISSN 1941-6806
doi: 10.3827/faoj.2018.1301.0006

1 – Podiatric Surgery Resident, Department of Veteran Affairs at San Francisco
2 – Podiatric Medical Student, California School of Podiatric Medicine
3 – Assistant Professor, Department of Orthopaedic Surgery, University of California at San Francisco
* – Corresponding author:

Müller-Weiss syndrome is a rare disease that is described as a spontaneous adult-onset tarsal navicular osteonecrosis [1]. Symptoms include chronic midfoot pain, swelling, and tenderness on the dorsal and medial midfoot. It is commonly found bilaterally and is found more frequently in women [1]. Its pathogenesis remains controversial. Some believe it to be caused by secondary compressive forces acting on the tarsus or possibly a congenital defect, while others believe it to be an ischemic process[2]. The characteristic findings for Müller-Weiss syndrome include a dorsomedial dislocation along with the collapse of the lateral navicular bone, resulting in a comma-shaped.

The first description of this condition was in the early twentieth century in Europe. In 1925, Schmidt reported on a patient with pluriglandular endocrine failure with deformities at the tarsal navicular. Walther Müller described this condition in 1927, where he suggested that the disease developed from a forceful compression of the lesser tarsus. Müller later suggested a congenital defect was the cause of the disease the following year [3]. Also, in 1927, an Austrian radiologist, Konrad Weiss, described similar findings in two patients suggesting osteonecrosis as the cause for the condition [4]. Although Schmidt was the first to describe this condition, the disease is named after Müller and Weiss.

The exact prevalence and incidence of this disease is currently unknown. However, there are isolated case reports throughout the literature. It is commonly present in the fourth to sixth decade of life. It is also frequently bilateral and usually found in patients with a higher body mass index. There is limited data suggesting an environmental and nutritional component [5]

The pathogenesis of this condition is poorly understood. However, the literature suggests that there are two contributing factors; a delay in ossification of the navicular and atypical compressive forces on the midfoot. 

There are multiple factors that can contribute to a delay in ossification including poor nutritional status, endocrinopathies, metabolic disease, or malabsorption disease [5]. When there is a delay in the ossification of the navicular, the weak outer chondral surface is susceptible to abnormal development from excessive compressive forces. Current literature suggests a large compressive force would contribute to plastic deformation of the navicular during ossification [5]. However, it is possible that persistent low compressive forces on the pliable chondral surface puts the navicular at risk of ossifying in an irregular orientation. 

The second contributing factor is a result of the biomechanical insult on the navicular. As mentioned previously, excessive compressive forces on the navicular is suggested to contribute to this condition. This is particularly true when these forces are applied to the lateral half of the navicular between the talar head and the cuneiforms. There are several conditions which can lead to compressive forces to the lateral aspect of the navicular including: primary subtalar joint varus, first ray brachymetatarsia (both congenital or acquired), and clubfoot deformities [5]. Other biomechanical factors such as a short hallux metatarsal, shortening of the entire medial column due to internal rotation of the navicular in the transverse plane, or retroposition of the first tarsometatarsal joint in relation to the second tarsometatarsal joint can also contribute to lateralization forces [5]. When the first ray is hypermobile, loading forces transfer to the second ray which may also lead to compressive forces into the intermediate cuneiform and lateral navicular [5]. 

Case Report

A 41-year-old male with a past medical history of right foot plantar fasciitis, depression, and insomnia was brought in by ambulance to the Emergency Department of San Francisco General Hospital with a chief complaint of 10/10 right foot pain accompanied by swelling. Two days prior, the patient had been exercising at his gym. He did not recall any particular injury apart from his right foot slipping off exercise equipment onto the floor, without any immediate pain. Several hours after exercising, he noticed a gradual increase in right foot pain. In the Emergency Department, plain films did not demonstrate fracture, there was diffuse soft tissue swelling on the dorsum of the foot (Figure 1),  labs were not drawn, however, the patient’s vital signs were all within normal limits. He was discharged from the ED with an ankle brace, crutches, and Tylenol for pain relief.

He again visited the ED 3 days later, with a further increase in pain and edema; he was not found to have any underlying fluctuance or erythema. He remained unable to bear weight on his right foot. He remained in an ankle brace and had been using ibuprofen without any significant pain relief, and he continued to not have any constitutional symptoms. Radiographs demonstrated increased soft tissue swelling from prior films, however, no evidence of fractures, soft tissue calcifications, or joint effusions were seen. He was recommended to continue use of the ankle brace, to stop ibuprofen, and trial Tylenol.  

Nearly one month later he presented to the ED with continued pain, however now able to bear weight. He had plain films which demonstrated even further increase in soft tissue swelling as well as a CT (Figure 2) with findings of prominent osteopenia involving the midfoot. Orthotics and Prosthetics was consulted and he was dispensed a CAM boot. The podiatry service was notified, and an appointment was made for the following day in the clinic. He was dispensed opioid pain medication, as well as ibuprofen, at discharge.

The next day, he presented to the Podiatry Clinic. His right dorsal foot was edematous and erythematous from the metatarsal heads to the level of the ankle joint. Fluctuance was not appreciated. The right dorsal foot was tender to palpation.

Figure 1 Radiographs of patient’s foot. Diffuse swelling on the dorsum of the foot without evidence of fracture or dislocation.

Figure 2 Sagittal CT demonstrating further soft tissue swelling with prominent osteopenia of the midfoot.

Allodynia was present. Pain increased with plantarflexion of the right ankle joint. Pain was also present with eversion and inversion of the right subtalar joint. He was unable to wear the CAM boot, dispensed to him the prior day, as this increased his pain. A CBC, ESR, CRP, BMP, and HgA1c, and a MRI with contrast were ordered to assess for abscess or osteomyelitis. His ESR and CRP were >130 mm/h and 198.0 mg/L, respectively. His HgA1C was 5.9%, and his uric acid level was 3.7 mg/dL. He was without leukocytosis and his remaining labs were unremarkable. An ACE wrap was applied from the foot to the tibial tuberosity to compress the foot. The patient was given strict instructions to elevate, do ROM exercises, and wear the CAM walker boot at a 90 degree angle to prevent worsening flexion contracture. He was given explicit instructions to return to the ED if he developed any fever, chills, nausea, and vomiting or any worsening pain. He was dispensed gabapentin to be taken at bedtime for pain. 

The previously ordered MRI was taken and reviewed. Findings were reviewed with radiology, and they were suggestive of broad diagnoses. Clinically and radiographically there was support of complex regional pain syndrome.  It showed destruction of joint spaces at the TN joint, subtalar joint, as well as deep marrow edema within the midfoot outside of the talonavicular joint (Figure 3). The navicular bone was almost entirely replaced with edema and enhancement.The MRI findings were also consistent to support Charcot arthropathy and osteomyelitis as well. Septic joint was also on the differential due to minimal fluid within joint spaces. Interventional Radiology was consulted for urgent bone biopsy. There would be no growth from the cultures of the specimen acquired.

The patient then underwent a right foot irrigation and debridement with bone biopsy approximately one week later with the presumption of infection versus complex regional pain syndrome. At this time the symptoms began 3 months prior. Gout was lowest on the differential due to a prior uric acid level of 3.7 mg/dL. In the operating room, a 4 cm incision was made dorsally to gain access to the talonavicular joint. A Rongeur forceps was used to collect a sample of synovial tissue which was noted to appear inflamed and thickened; this was sent to microbiology. The talus and navicular were assessed and noted to be hard and viable. A sample of cartilage and bone was taken from both the talus and the navicular and sent to microbiology. Bone specimens were also sent to pathology from both talus and navicular. The patient would subsequently be admitted to the hospital. 

Figure 3 Sagittal and transverse T2 MR imaging demonstrating destruction of the talonavicular joint with extensive marrow edema that was also present to the calcaneus and cuneiforms.

During his hospital stay, neurology was consulted to rule out CRPS. He was noted to not have any evidence of neuropathy with “intact afferent and efferent limbs of reflex arc.” Neurology assessed a low suspicion of neuropathic etiology of symptoms. In terms of the acquired specimens from the OR, there was no growth noted from any of the specimens (C&S, AFB, and fungal). The synovial tissue final pathologic diagnosis was noted to be “lymphoplasmacytic inflammation.” Excised bone of both the talus and the navicular were noted to be without any evidence of acute osteomyelitis.  

Figure 4 Radiographs demonstrating focal osteopenia and erosive changes of the talonavicular joint.

The patient remained in-house for 5 days; he was then discharged home. Two days after discharge he returned to the clinic; he was now one week status post biopsy. He remained without constitutional symptoms.  The differential diagnosis remained the same at this point, with complex regional pain syndrome as most likely diagnosis despite low suspicion from the Neurology team. New labs were ordered. Rheumatoid factor was noted to be within normal limits <3.5 IU/mL and antinuclear antibody was noted to be negative as well. His ESR had decreased to 68 mm/h and his CRP had decreased to 6.4 mg/L. The patient was encouraged to continue ambulating with a CAM boot and to practice ROM exercises. He would later follow up with the infectious disease clinic who noted that “osteopenia and marrow enhancement on imaging, elevated inflammatory markers, and absence of evidence for neuropathy on exam (making Charcot arthropathy unlikely) are concerning for infectious etiology.” 

Figure 5 Immediate post-operative films of the talonavicular fusion.

However, both cultures and pathology were without evidence of osteomyelitis and he did not have a systemic illness which could have led to hematologic seeding or skin breaks down allowing for direct inoculation. Serologies were sent to rule out less common infectious agents, such as TB and coccidioides. The serologies were noted to be negative for both TB and coccidioides.  The patient returned to the Podiatry Clinic two weeks later, now 3 weeks status postbiopsy and almost four months from the time of onset of symptoms. He attempted to ambulate in his CAM boot but was unable to do due 5/10 throbbing pain along his medial arch. He continued to not have any constitutional symptoms. He was encouraged to transition to regular shoes and discontinued the CAM boot. His sutures were removed at this visit. Since he had been discharged from the hospital, he had begun taking a new pain management regimen of gabapentin 300 three times daily which he noted to help alleviate some pain.

The patient returned to the clinic 5 weeks status post the open biopsy. He was still unable to walk in regular shoe wear and remained in his CAM boot utilizing a knee scooter. It had been two months since he last tried physical therapy and he wished to restart therapy. New plain film imaging was taken, and noted to be without any interval changes. He was encouraged to ambulate in regular shoe wear and to mobilize the foot as much as possible. It was stressed that weight bearing was imperative to make a recovery.

Two weeks later the patient returned to the clinic with new plain films. He was now 7 weeks status postbiopsy. He attempted to ambulate only utilizing the CAM boot but remained unable to bear weight on his right foot in regular shoe wear. On plain film imaging he was noted to have unchanged severe osteopenia from prior films, however with more focal osteopenia/erosion involving the talonavicular joint (Figure 4). X-ray findings correlated with TNJ degenerative joint disease.  

At this point in summary, neurology had evaluated the patient and had very low suspicion for complex regional pain syndrome. Medical workup had also been negative for inflammatory arthritis. Of note, the patient had no risk factors for Charcot arthropathy. The case was discussed on multiple accounts with the orthopaedic department and the patient was then placed in a short leg cast, made non-weight bearing, with a plan of serial casting with imaging to promote autofusion of the TNJ. If the patient was to continue to have pain, surgical fusion of the TNJ would be considered. 

The patient returned to the clinic 2 weeks, now 6 months status-post the initial onset of pain, and now with new assessment of TNJ degenerative joint disease secondary to unknown etiology with differential of CRPS, Müller-Weiss syndrome, septic joint, or osteomyelitis. 

Figure 6 Eight weeks post-operative films demonstrating trabeculation across the arthrodesis site.

He had remained in a short leg cast and NWB as instructed, and ambulating with a knee scooter. He remained without constitutional symptoms. At this time, surgery for fusion was discussed, as well as conservative treatment of serial casting. Patient opted to go with the latter. It was discussed that 6-8 weeks of serial casting may be adequate for fusion. Patient was again casted and he followed up again 2 weeks later. Again, surgery was discussed as the patient had no change in his symptoms, and was placed in a CAM boot with a plan for incisional biopsy.

The patient then opted to undergo a right foot incisional biopsy of the talus and a TN joint preparation for fusion. The patient returned to the operating room now just over 8 months from the initial onset of pain and symptoms. An incision was made through the prior incision site and deepend down to the talonavicular joint and a capsulotomy was performed. A pseudoarthrosis was noted. The articular surface of the navicular and talus were exposed and the surfaces were noted to have patchy areas of hyaline and fibrocartilage. A curette was then used to resect three separate specimens consisting of cortical bone from the articular surfaces of the navicular and the talus. This procedure’s goal was to prepare the joint for fusion and for a final biopsy. Fungal, bacterial, and acid fast bacilli would all be negative for growth.

The patient returned to the operating room for a third and final time, to undergo a right foot talonavicular arthrodesis with iliac crest bone graft at 9 months from onset of symptoms. An incision was made approximately 10 cm from the talar neck to the base of the first metatarsal. Dissection was carried down to the talonavicular joint was prepared utilizing curettes, fish scaled with osteotomes, and fenestrated using 0.062 K-wire. Attention was then directed to the right anterior superior iliac spine to acquire autograft. The talonavicular site was temporarily fixated and a combination of cancellous autograft, cancellous allograft bone chips, and 10 cc of Stimulan Biocomposite calcium sulfate were placed into the talonavicular arthrodesis site around the structural iliac crest autograft. Next, the talonavicular arthrodesis site was then fixated with a small Wright Medical medial column fusion plate and 3.5 mm fully threaded locking and nonlocking screws (Figure 5). The patient was then subsequently admitted for 48 hours for observation. Intraoperative bacterial cultures from bone were acquired but would be negative for growth.

The patient remained non-weight bearing for a total of 12 weeks, both with a short leg cast for the first 8 weeks followed by a CAM boot with ROM exercises for an additional 4 weeks. Serial radiographs demonstrated uneventful healing of the arthrodesis site (Figure 6). 

He continued to be followed weekly in the Podiatry Clinic. He continued to have interval changes of healing of the arthrodesis site on serial x-rays. The patient continued to work with physical therapy, primarily range of motion exercises. At 11 months he was noted to have significant improvement in pain during ambulation. He was able to transition to regular shoe wear at this time. At 13 months, he was noted to have 1/10 level of pain. At this point, he felt that he could return to day to day activities without restriction. There were no complications from any of the surgical interventions at his last follow up visit of this review, 13 months from the onset of symptoms. 


This is an atypical presentation of Müller-Weiss. The inciting event was minor trauma, however, this is per the patient’s report, and therefore is subjective. The first ray mobility was not evaluated prior to the initial presentation. The patient had swelling and pain of the midfoot, however, this was unilateral. Although the patient did not have a higher than average BMI, he was athletic and he had exceedingly high midfoot torque on his foot during exercise routines. The appropriate steps in the management of other diseases including  complex regional pain syndrome were met.  Biopsies were taken to rule out infectious causes, and multiple serologies were taken, even to exclude TB.  Multiple imaging modalities were also used.  The patient was directed to pain management, and he was treated by physical therapy before and prior to the talonavicular fusion; he improved following the procedure of a talonavicular joint arthrodesis. 

Apart from minor trauma, the unilateral destruction of the talonavicular joint is what makes this case unique. Müller-Weiss syndrome is often bilateral and not following any incidence of trauma.  It is possible in this case that the initial inflammatory phase of this disease process leads to the eventual destruction of this patient’s talonavicular joint, resulting in the need for an arthrodesis. This would explain why he would make a recovery following this procedure in conjunction with continuing physical therapy. We therefore believe that this is an atypical case of complex  Müller-Weiss Syndrome, although atypical. 

Conflict of Interest Declaration

The corresponding and contributing authors have no relevant financial interest in this manuscript.


  1. Sharp RJ, Calder JDF, Saxby TS. Osteochondritis of the navicular: a case report. Foot Ankle Int 2003; 24:509–513  
  2. Müller W. Uber eine eigenartige doppelseitige Verãnderung des os naviculare beim Erwachsenen. Deutsche Zeitschrift fur chirurgie Leipzig 1927; 201:84-7.
  3. Nguyen, AS, Tagoylo GH, Mote GA. Diagnostic imaging of the Mueller-Weiss syndrome: findings of a rare condition of the foot.  J Am Podiatr Med Assoc. 2014 Jan-Feb;104(1):110-4.
  4. Weiss K. Über die “malaizie” des os naviculare pedis. Fortschritte auf dem Gebiete der Röntgenstrahlen 1927;45:63-7.
  5. Mohiuddin T, Jennison T, Damany, D. “Müller-Weiss disease. Review of Current Knowledge” Foot and Ankle Surgery, 2014, 20;79-84.
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The geographic distribution of podiatrists in Perth, Western Australia

by Sara Hashemi1*, Estie Kruger1, Marc Tennant1

The Foot and Ankle Online Journal 13 (1): 5

This study examined the spatial accessibility of podiatry services to aged people living in the Greater Perth area, and access to these services for people from different socioeconomic groups, using geographic information systems (GIS). All persons older than 65 years (n=216 062) were included in the study and divided into two subgroups (retirees and elders) by age. Census data, bus stops (high and medium accessible stops) and train station data were integrated with GIS to analyse population spatial accessibility. The study found that most of the aged population resided within 2 kilometers of podiatry clinics, and the podiatry services are well distributed. In terms of access to buses, around three-fifths of aged people lived within 1 kilometer of high-access bus stops, and more than four-fifths of this population resided within 1 kilometer of medium-access bus stops. The distribution of podiatrists among people from different socioeconomic areas showed the density of podiatry services was higher in more affluent areas, therefore, the Inverse Care Law is evident in access to podiatry services in the Greater Perth region. 

Keywords: aged population, podiatry services, spatial accessibility, density, buses,  trains

ISSN 1941-6806
doi: 10.3827/faoj.2018.1301.0005

1 – International Research Collaborative – Oral Health and Equity, Department of Human Sciences, The University of Western Australia.
* – Corresponding author:

Western Australia is geographically the largest state in Australia, with a total area of more than 2.5 million square kms (a third of the total area of Australia) and a population (in 2011) of 2.2 million people [1]. Of this population 1.7 million people (77%) are living in the capital city, Perth.  In recent years, the population growth was double that of other cities in Australia [2].  A little over 200,000 residents of Perth are over the age of 65 years, and it is forecasted that the age structure in Perth will change consistent with the global trend in developed countries. The predictions are that there will be a decrease in the working-age population from 89% to 64%, and an increase in retirement age proportion of people to 66% by 2026 [3]. Clearly this shift in population demographics will require substantial and rapid planning for health and welfare services over the next decade. Australia is thus facing the classic developed country issues of an aging population whilst being relatively wealthy and it being substantially a healthy population [4]. Many health services are available, both public and private, but the use of these services depend on geographic accessibility. Australian cities are not densely packed cities and the reliance on vehicle transport is high.  Geographical accessibility to healthcare services is one of the fundamental components of healthcare [5]. The ageing of the Australian population has already, and will continue to drive strong growth in podiatry services ( This study examined the spatial accessibility of podiatry services to the population of the Australian metropolis of Perth, using a geographic information system (GIS) approach, with a focus on the retired and elders, and taking transport options into consideration. 


As only openly accessible and freely available data were used in this study, no ethics approval was required.

Podiatry practice locations: The podiatry directory from November 2015 was used to determine public service locations [7]. This directory updates every year and shares information about the Department of Health (DOH) and publicly funded podiatry services available in Western Australia. The private services were gathered from the yellow pages and addresses were confirmed with Google maps.

Population data: All population data (including age distribution) were obtained from the 2011 Census. The data frameset for this study include all people living within 50 km of the Central Post Office in Perth. Population groups were categorized according to age, with a focus on retirees and elders. Retirees included all people older than 65 years old, and elders include all those older than 85 years. 

Train systems in Perth: Perth, like the other Australian capital cities, has a comprehensive local train network. There are four Perth train lines, radiating out from the main Perth city train station [8]. All the train stations were included in this study. The geographic data for train stations is available on the TransPerth website  (

Bus system in Perth: Two bus terminals are located in the Perth metropolis: the Wellington street bus station and the City Bus port. The Wellington street bus station is approximately 200m from the main city centre train station, and services the northern suburbs. The geographic data for bus stations were available from the Transperth website (  High and medium frequency bus stops were considered separately. The “high” frequency stops were where busses stop at least 48 times per day (every 15 minutes) and “medium” had a lower frequency of less than 48  busses per day.

Population data and socioeconomics: Census data from the most recently available (and geo-coded) census (2011) were used for the study ( A total of 1976 Perth SA1’s (the smallest geographic area the census data is divided into) had centroids within 50 km of the central post office. Consistent with previous studies this was deemed to be the Greater Perth region and used in the study as the definition of Perth.

The socioeconomic status of the population was analyzed using the Socioeconomic Index for Areas (SEIFA). The Australian Bureau of Statistics (ABS) uses SEIFA, a composite index of relative socioeconomic disadvantage, and determined from indicators collected by the ABS within each set of census data. In this research the deciles of SEIFA will be dichotomized, with deciles 1-5 classified as low socioeconomic, and the deciles 6-10 classified as high socioeconomic.
Data integration and analysis: All data were integrated using QGIS (version 10.0), and analyses were completed using Excel (version 2010;Microsoft Corporation, Seattle, WA, USA). QGIS software was used to formulate an integrated buffer zone around each podiatry service location, train and bus stations. Two optional zone radii were applied; zone A was 1 km wide, and zone B was within a 2 km radius from a podiatry service location. 


The aged population and podiatry locations: The aged population (65 years and over) living in the Greater Perth area was 216,062, of which 187,925 were retired (65-84 years old) and the others, 28 137, were elders (over 85 years old). A total of 104,928 adults (retiree and elderly) lived within zone A (within 1km of a podiatry service), whilst 73,875 adults lived within zone B (between 1 km and 2 km of a podiatry clinic). These, respectively, constituted 48.6% and 34.2% of the total retirees and elders’ population of Greater Perth. For retirees, 89,21 (47.6%) lived within zone A, and 64,118 (34.1%) lived within zone B. For the elders, 15,407 (54.7%) and 9,757 (34.7%), respectively, resided in zone A and B (Table 1).

The aged population and bus stops (high and medium stops): In this study high and medium bus stops have also been investigated (the stations with high and medium numbers of times that the bus stops, or frequency of stops). 

Adults Within 1 km 

(Zone A)

Within 2 km

(Zone B)

Outside 2 km Total
Retirees 89,521 








Elderly 15,407








Total 104,928








Table 1 The number and percent of retirees (65-84 years old) and elderly (over 85 years old) living within 1 km, 2 km and outside 2 km of a podiatry service in Greater Perth.

Figure 1 Podiatry services locations in the Perth metropolitan area (green stars for private services and the pink for public services),  and  1 km buffer zones around  high frequency bus stops (blue circles).

A total of 129,485 retirees and elderly lived within 1km of high frequency bus stops (Figure 1), and 182 459 adults lived within 1 km of medium frequency bus stops (Figure 2). These, respectively, constituted 60% and 84% of the 216,062 total retirees and elders’ population of Greater Perth. For retirees, 110,426 (59%) lived within 1 km of high frequency bus stops, and 157,778 (84%) lived within 1 km of medium frequency bus stops. For the elders, 19,059 (68%) and 24,681 (88%), respectively, lives within 1km of high and medium frequency bus stops (Table 2). 

The aging population and train stations: This study identified the density of the aging population living next to train stations (Table 3). A total of 35,273 retirees and elders lived within 1km of train stations, and this amounts to around 16% of the aged population in Greater Perth (Figure 3). 

Adult Within 1km of high bus stops Within 1km of medium bus stops
Retirees 110,426




Elderly 19,059 




Total 129,485 




Table 2 The number and per cent of the aging population living within 1 km of high and medium bus stops in Greater Perth.

Figure 2 Podiatry services locations in the Perth metropolitan area (green stars for private services and the pink  for public services),  and  1 km buffer zones around medium frequency bus stops (orange circles).

Within 1km Within 2km Outside 2km Total
Retirees 29,547 




120,616 (64.2%) 187,925 


Elderly 5,726 








Total 35,273 




136,747 (63.3%) 216,062 


Table 3 The number of older people living next to 1km of train stations.

Around 20% of this population lived within 2km of train stations and the rest (63%) lived outside 2km of train stations.

Socioeconomics: SEIFA was used to examine the relative socioeconomic status and proximity to podiatry services and public transport, and found lower percentages of the most disadvantaged half of the population (the first five deciles) lived closer to podiatry services, compare to the least disadvantaged half of the population (Table 4).

Figure 3 Podiatry services locations in the Perth metropolitan area (green stars for private services and the pink  for public services),  and  1 km buffer zones around train stations. 

Table 4 The number and percent of retirees (older than 65 years old) and elderly (older than 85 years old) living within zone A, zone B, high and medium bus stops and 1km and 2km of a train station, divided by Socioeconomic Index for Areas (SEIFA) deciles* in metropolitan Perth. Note: The percent shows the percentage of total aging population. * Decile 1=poorest, decile 10 =wealthiest.


Spatial accessibility to healthcare facilities has been the focus of many studies in Australia, with the distance to facilities being highlighted as a barrier to access and subsequent utilisation of services (10). In total, 82% of retired (48% in zone A and 34.1% in zone B) and 89.4% of elders (55% in zone A and 35% in zone B) lived within 2 km of podiatry clinics, which it is 82.8% of the total aging population in Greater Perth. This information shows that podiatry services are distributed relatively uniformly among this population (Table 1) and most aged people have access to a podiatrist within a 2 km distance at most. Most of the aging population resided within 1km of high and medium bus stops, and therefore most of the retired and elders can use buses to visit podiatrists (Table 2).

There was a different trend in the distribution of train stations among the retired and elders, compared to proximity of them to bus stops, the train stations were not a suitable selection to access podiatry locations. In total, 36% of the retired population lived within 2km of train stations (15.7% within 1km and 20.1% within 2km) and 43% of elders resided within 2km (20% within 1km and 22% within 2km). In total, 36.7% of the whole aging population resided within 2 km of a train station.

In conclusion, access to podiatry services via train stations, does not seem to be a suitable option (Table 3), because 63% of total aging people resided outside of 2km from a train station. This study also focused on the public transportation accessibility of aged people from different socioeconomic backgrounds. Public transportation is very important to the older population in general, as they depend more on public transportation than young people. Also, older people, (especially after 70 years of age) start to surrender their driving licenses and depend on others to transport them to health facilities (11). They have limitations of using and driving personal vehicles, whilst at the same time experiencing a greater need for health care (12). However although retirees and elders depend on public transport, a lower proportion of them were living in close proximity to train stations.

The relative socioeconomic status and proximity to podiatry clinics, bus stops and train stations have been investigated, and the most disadvantaged of the retired and elders were less likely to live within up to 2 km of podiatry services (zone A and B) compared to wealthier older people. This data shows that the distribution of podiatrists were more likely to be among wealthier people, than people from lower socioeconomic areas. Only 17.4% of the total aged population lived outside of zone B. In terms of accessibility to bus stops (high and medium) within 1km, the wealthier groups had more spatial accessibility to both high and medium bus stops (34.4% and 48% respectively), while the low income people had less accessibility to bus stops, 25.5% for high and 36.5% for the medium stops. This difference is not too significant. In comparison between poor and wealthy aged people and access to train stations (within 2km) has shown that there were significant differences between these two groups., Only 14.4%  of retired and elders from disadvantaged areas  were located within 1 and 2 km of train stations (12.2% retired and 2.2% elders). The percentage of the aging population with high socioeconomic status was 22% within up to 2km of train (19% retired and 3.3% elders). This study indicated that the higher percentage of the aging population (63.3%) with different socioeconomic resided outside of 2km of train stations. According to this data, the Inverse Care Law applies to the  aged population in the Greater Perth metropolitan area. The definition of this law is “The availability of good medical care tends to vary inversely with the need for it in the population served”(13). On the other hand, public transportation was located closer to wealthier populations. It should be investigated to determine if  people from wealthier areas suffer from higher burdens of foot problems or diseases associated with foot health (such as diabetes), than those from poorer areas.   It might be that those from more disadvantaged areas are more unaware of feet health, or that the cost and affordability of podiatric care act as a barrier to obtain care. 


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The psychology of pain: A retrospective study examining correlation between number of listed allergies on patients’ medical charts and PACU pain rating

by Justin D. Guiliana, DPM1*; Rebekah Cherian, DPM2; Brent H. Bernstein, DPM3

The Foot and Ankle Online Journal 13 (1): 4

Pain is a complex entity of any pre- or postoperative workup, and serves as a subject matter comprised of several aspects. Some make an argument that pain should be considered as the “5th vital sign”. Effective pain control pre- and postoperatively is an important aspect to patient care. However, the ability to properly control pain can be limited based on the amount of allergies the patient has. The goal of this paper was to examine if a correlation exists between the number of listed allergies on a patient’s medical chart, and immediate postoperative pain rating in PACU. We believed that a correlation would exist between patient reported allergies (PRAs), and PACU pain rating. The results of this study showed that patient reported allergies (PRAs) did not serve as a prognostic indicator for PACU pain rating status post lower extremity podiatric surgical procedures. 

Keywords: postoperative pain rating, allergies, podiatry, psychology, pain management

ISSN 1941-6806
doi: 10.3827/faoj.2018.1301.0004

1 – Resident, St. Luke’s University Health Network, Bethlehem, PA
2 – Texas Foot & Ankle Specialists, Mesquite, TX
3 – St. Luke’s Podiatry, Bethlehem, PA
* – Corresponding author:

Plato believed that pain arose from within the body and indicated it to be more of an emotional experience with sensory, cognitive, motivational, and affective qualities. Pain is known to surpass literal tactile sensation, or the physical awareness of pain. In addition, it also includes perception, learned behaviors, and subjective interpretation of perceived discomforts [1,2]. In the past, studies have examined patient-reported allergies in association with satisfaction scores after lower extremity total knee and total hip arthroplasties [3]. These studies revealed that PRAs did serve as a prognostic indicator in patient reported satisfaction, however no such study had been performed in the podiatric surgical population. The purpose of this paper is to further evaluate the relationship between the number of patient reported allergies and postoperative pain rating to see if a correlation exists.   

Patients and Methods 

A retrospective study was conducted examining surgical patients over the span of a little over 3 months, from July 3rd, 2017 through October 3rd, 2017. A total of 122 patients were utilized in the study. All patients were consecutively selected utilizing Epic analytics from a surgical podiatric practice. Each patient’s chart was examined to gather the number of patient-reported allergies after which PACU pain rating was rated. This includes all listed allergies, be they true allergies eliciting an anaphylactic type of reaction or be they “allergies” eliciting more a side effect type of reaction. The PACU pain rating was obtained by each patient, and documented by the PACU nursing staff.

Anesthesia Type Total
General Anesthesia General with popliteal block IV sedation
Surgery  Type ST # of patients 29 1 7 37
Row percent 23.97% 0.83% 5.79% 30.59%
B # of patients 49 3 19 71
Row percent 40.50% 2.48% 15.70% 58.68%
B + ST # of patients 8 3 2 13
Row percent 6.61% 2.48% 1.65% 10.73%
Total # of patients 86 7 28 121
Row percent 71.07% 5.79% 23.14% 100%

Table 1 Cross Tabulation of Two Variables.

Allergies Pain
Spearman’s Rho Allergies Correlation coefficient 1.000 0.041
Sig. (2-tailed) 0.656
n 122 122
Pain Correlation coefficient 0.041 1.000
Sig. (2-tailed) 0.656
n 122 122

Table 2 Correlations.

Figure 1 Scatterplot results.

The type of surgery was also evaluated, whether it was soft tissue alone (ST) (ie: endoscopic plantar fasciitis, ganglion cysts remove, tenotomy, soft tissue mass excision) vs. bone alone (B) (ie: hammertoe, Austin bunionectomy, osteotomy) vs. both soft tissue and bone (B+ST) (ie: Austin with extensor hallucis brevis (EHB) tenotomy). As seen in Table 1, there were a total of 37 patients that received soft tissue procedures alone, 71 patients that received bone procedures alone, and 13 patients that received bone and soft tissue procedures. 

Type of anesthesia was noted and grouped into 3 categories: general without popliteal block, general with popliteal block, or IV sedation. The total number of patients receiving each type of anesthesia are also displayed in Table 1. Spearman’s correlation was run to evaluate if PRAs had prognostic value for PACU pain rating. In addition, the type of anesthesia received pre-emptively was utilized to evaluate if one form of anesthesia over another in relation to procedure type had prognostic value in PACU pain rating. 


All statistical analyses were conducted in IBM SPSS for Windows Version 18.
A Spearman’s correlation was computed to assess the relationship between the number of patient’s allergies and their pain scale. These results can be seen tin Table 2. Results showed that there was no correlation between the two variables (r=0.04, n=122, P-value =1.00). The scatter plot in Figure 1 summarizes the results. P-value <0.05 was considered significant. These results show there is no correlation between the number of patient’s allergies and their pain scale. 

To see any association between type of surgery and anesthesia, a cross tabulation was done. These results can be seen in Table 1. Since more than 20% of the cells had less than four patients, a Chi Square Test was not recommended. Instead, it was best to report descriptive statistics only. 


Pain is an extremely complex aspect of medicine not only to evaluate, but to effectively manage as well. Pain is a biological, as well as learned aspect. Pain can be learned from cultural, psychological, emotional, and financial backgrounds. Prior studies have shown that how we experience a painful event is strongly influenced by our prior learning history [1,2]. Therefore, effectively managing and addressing a patient’s pain, especially in the postoperative time frame, serves as a challenge to the physician and treatment team. 

This retrospective study sought to evaluate if there exists a correlation between the number of listed allergies on a patient’s medical record and their PACU pain rating scale. The Spearman’s correlation revealed no correlation between the two variables. No correlation could be found regardless of the type of surgery was performed, or what type of anesthesia the patient received preoperatively. 

Although our hypothesis did not hold true, the results serve as an indicator in the fact that pain is indeed extremely complex and serves as a challenge for medical professionals to effectively manage. Although the authors do not necessarily believe that pain should be considered the “5th vital sign”, it is believed that more emphasis should be given to patient’s allergy list in properly addressing preemptive pain management for surgical patients. 

Although an increasing number of patient-reported allergies was not seen to be associated with worse pain ratings, several limitations were present during this study. Some limitations of this study were inclusive of population size, and the challenge of objectively analyzing such a subjective topic. Only having utilized data from one surgical practice limits our study. In addition, different factors which have been known to contribute with subjective outcome measures include: race and ethnicity, education levels, and learned behaviors drawn from past-life experiences. In the future, to more accurately assess and predict the outcome of rated pain postoperatively in podiatric surgeries, this study can delve further into individual demographic, experiences, and learned behaviors

Disclosure: The authors declare that they have no relevant or material financial interests that relate to the research described in this paper


  1. Koban L, Kusko D, Wager TD. Generalization of learned pain modulation depends on explicit learning. Acta Psychologica. 75-84, 2017.
  2. Horn-Hofmann C, Scheel J., Dimova V., Parthum A., Carbon R., Griessinger N., Sitti R., Lautenbacher S. Prediction of persistent postoperative pain: Pain- specific psychological variables compared with acute postoperative pain and general psychological variables. European Journal of Pain, 191-202, 2017.
  3. McLawhorn AS, Bjerke-Droll BT, Blevins JL, Sculco PK, Lee Y., Jerabek SA. Patient-Reported Allergies Are Associated With Poorer Patient Satisfaction and Outcomes After Lower Extremity Arthroplasty: A Retrospective Cohort Study. Journal of Arthroplasty, 1132-1136, 2018.

A 12-month review of patients with advanced metatarsophalangeal joint osteoarthritis undergoing synthetic cartilage hemi implant arthroplasty

by James Lee Harmer FCPodS, MSc, BSc (Hons)1*; Anthony John Maher FCPodS, MSc, BSc (Hons)2 

The Foot and Ankle Online Journal 13 (1): 3

The aim of this study was to present patient reported outcomes (PROMS) and complications at 6 and 12 months following metatarsophalangeal joint (MTPJ) hemiarthroplasty with a synthetic cartilage hemi implant in patients with advanced MTPJ arthritic degeneration treated by a surgery team in the English National Health Service. Over a 12-month period between January 2016 and February 2017 a total of 20 patients underwent MTPJ hemiarthroplasty with a synthetic cartilage hemi implant. Patients were reviewed at both 6 and 12 months. All outcome data were collected using the PASCOM-10 audit database, an online resource which is able to report clinical and patient reported outcomes for selected cohorts. At 6 months, 65% of patients felt that their original complaint was now better or much better, while 4 patients (20%) felt their foot condition had deteriorated. At 12 months, 60% of patients felt better or much better and only 1 patient (5%) reported a deterioration in their foot condition. At 6 months 80% of patients felt that their original expectations from before surgery had been met or partly met and 95% reported they would be prepared to have surgery performed under the same conditions again; this reduced to 75% and 80% respectively by 12 months. The most common complication was joint pain and stiffness (60%) at 6 months, and 25% of the cohort had the implant revised to a joint destructive procedure by 12 months. Initial results for the synthetic cartilage hemi implant arthroplasty for the surgical treatment of advanced MTPJ arthritic degeneration were disappointing and did not compare well with previous studies. Although validated PROMS demonstrate a subtle improvement in health related quality of life and patient satisfaction at 6 months and 12 months, the results were not convincing and both complication and revision rates were high. 

Keywords: metatarsophalangeal, osteoarthritis, implant arthroplasty

ISSN 1941-6806
doi: 10.3827/faoj.2018.1301.0003

1 – Specialist Registrar in Podiatric Surgery, Nottinghamshire Healthcare NHS Foundation Trust, Department of Podiatric Surgery, Park House Health Centre.
2 – Consultant Podiatric Surgeon, Nottinghamshire Healthcare NHS Foundation Trust, Department of Podiatric Surgery, Park House Health Centre. 
* – Corresponding author:

Historically arthrodesis for advanced arthritis of the 1st metatarsal phalangeal joint (MTPJ) was considered as the gold standard, with good reduction in pain and high patient satisfaction levels reported [1]. However, sacrificing the range of motion of the MTPJ following arthrodesis is not ideal, it can restrict footwear, interfere with activities that require joint motion, can lead to transfer metatarsalgia, and arthritic degeneration in adjacent joints [2]. A desire to preserve joint motion has prompted the development of several joint implants, unfortunately many have not lived up to expectations and have demonstrated high rates of failure as a result of loosening, malalignment, dislocation, subsidence, implant fragmentation, and bone loss [3-4]. The advancement of technology has led to the introduction of novel new implants one of which is the Cartiva® synthetic cartilage hemi implant arthroplasty (SCHIA) (Cartiva® Wright Medical Group N.V.). This is a polyvinyl alcohol (PVA) hydrogel MTPJ hemi implant. PVA has been used with great success in several different medical devices but it is particularly useful as a joint implant material as its viscoelasticity and tensile strength are very similar to healthy human articular cartilage [5-8]. 

Initial outcomes for the SCHIA appear promising, Buamhauer and colleagues in an industry funded prospective, randomised, multi-centred, clinical trial named ‘the Motion study’ followed 202 patients at two years and found the implant to be equivalent to 1st MTPJ arthrodesis for advanced hallux rigidus with the added advantage of maintaining dorsiflexion, reducing pain and having few safety concerns [9]. The study used 2:1 randomised allocation in favor of the implant group, 23% of the arthrodesis control group withdrew after initially consenting to randomisation, 152 implant patients and only 50 arthrodesis patients started the trail with a further 4% lost to follow-up by the end of the study. Although unfortunate, this disproportionate ratio of patients between the two groups may bias the results in favor of the implant group. A total of 11% of patients in the implant group underwent revision surgery with 9.2% of the implants failing and having to be converted to a 1st MTPJ arthrodesis. The root cause of the implant failure was not determined or discussed. Although implant patients’ VAS pain scores improved by >30% at 1 and 2 years follow-up these scores were higher than the MTPJ arthrodesis group at all time points, though not statistically significant. 

In a subset of 27 first MTPJ SCHIA patients followed up at five years, Daniel et al., showed an impressive 96% implant survivorship with only one implant having to be removed and converted to arthrodesis [10]. They also demonstrated continued improvements in function and pain scores over the five-year period compared to baseline scores for those patients with retained implants. Postoperative radiographs evaluation showed no bone loss, loosening or wear of the implant, and patient tolerance and satisfaction were high. They conclude that the SCHIA was a viable alternative to first MTPJ arthrodesis in the treatment of patients with advanced hallux rigidus, however generalizability of these results is limited, as only the first 43% of patients from the original RCT were evaluated, and no control group was included to compare results against. More recently the group have published their complete multi-centred midterm results for the SCHIA. They found that clinical and safety outcomes observed at two years were maintained at 5.8 years [11]. It is difficult to determine the relevance of these results as over 15% of patients were removed from the trial following revision to arthrodesis and it is unclear how a further 12% of patients progressed as they were lost to follow-up, hence results for almost a third of the original cohort were absent from the 5-year study.

Although not quite as common and certainly not as well covered in the literature as hallux rigidus lesser MTPJ degenerative joint disease can be equally debilitating and just as challenging for surgeons to treat [12]. Etiology can follow a similar course as a consequence of trauma, either acute or repetitive, and can lead to an interruption in the blood supply commonly affecting the 2nd metatarsal head, but any metatarsal can be affected resulting in avascular necrosis better known as Freiberg’s Infraction [12,13]. Freiberg’s is characterised radiographically by fissuring and fracture of the articular cartilage, leading to collapse and flattening of the metatarsal head, and finally resulting in severe arthritic degeneration of the joint, as described by Smillie in 1914 [13]. Surgical management is driven by the stage of the deformity and presence of arthritic degeneration. In advanced lesser MTPJ arthritic degeneration surgeons tend to shy away from arthrodesis and prefer to opt to maintain joint function with either excisional arthroplasty or implant arthroplasty [12]. The SCHIA is available in several sizes and although it has not received clearance in the USA for use in joints other than the 1st MTPJ, there is potential for it to be used as an alternative surgical option for advanced lesser MTPJ degeneration [14].    

The initial results from the MOTION study look promising, however further studies are still required to help substantiate their findings. The purpose of this study was to present patient reported outcomes and complications at 6 and 12 months following MTPJ SCHIA in patients with advanced MTPJ arthritic degeneration treated by a foot surgery team in the English National Health Service.  


A retrospective case series review of patients and their records was carried out at 6 and 12 months following MTPJ SCHIA. All patients over the age of 18 and who underwent surgery with the synthetic cartilage implant to address painful moderate to severe arthritic degeneration of an MTPJ, were included in the study. Patients with early MTPJ arthritic degeneration with minimal cartilage loss or those who had not previously received conservative care, or had marked transverse plane deformity were not offered surgery with the SCHIA. Over a 12-month period (Between January 2016 and February 2017) a total of 20 patients underwent MTPJ SCHIA. Surgical technique for SCHIA in the 1st MTPJ has previously been described in the literature [4,15].  Our surgical technique for implanting lesser MTPJ synthetic cartilage implants was no different except for the mobilisation of the sesamoid apparatus required in 1st MTPJ’s, all surgeries were combined with a dorsal joint cheilectomy. Surgeries were carried out under local anaesthesia with an ankle tourniquet by one of the department’s three surgeons. All patients were fit and healthy at the time of surgery and classed as either American Society of Anesthesiologists (ASA) 1 or ASA 2 [16] (Table 1). Mean Body Mass Index (BMI) was 27.9 ranging from (18.7 – 39.1) a third of the cohort had a BMI above 30. 

All patients underwent preoperative x-ray evaluation, patients diagnosed with hallux rigidus had their joint degeneration graded using the Coughlin and Shurnas classification system for hallux rigidus [17]. Patients diagnosed with lesser MTPJ degenerative disease were graded according to the Smillie classification system for Freiberg’s infraction [13] (Table 1). Subsequently seventeen 1st MTPJ, two 2nd MTPJ and one 3rd MTPJ hemi-arthroplasties were performed using a size appropriate synthetic cartilage implant. As long as wounds were healed patients returned to supportive footwear at two weeks and started a post-operative physiotherapy programme of 1st MTPJ strengthening and range of motion exercises.   Patients returned to the clinic on request and were reviewed by the authors at 6 months and 12 months following their surgical procedures. Governance approval for the study design was sought from Nottinghamshire Healthcare NHS Foundation Trust Research and Development Department.

All outcome data were collected using the PASCOM-10 audit database, an online resource which is able to report clinical and patient reported outcomes for selected cohorts [18]. PASCOM-10 benefits from the inclusion of a patient satisfaction questionnaire, the PSQ-10 [16]. For the measurement of patient-reported outcomes, PASCOM-10 uses the Manchester Oxford Foot/Ankle Questionnaire (MOXFQ), which is a validated measure of health-related quality of life (HRQOL) [19]. The MOXFQ assesses patient outcomes across 3 domains; pain, walking/standing, and social interaction with a maximum score of 100 in each domain. High scores signify poor HRQOL [20]. The PASCOM-10 system includes a reporting package, which was used to extract summary descriptive data for the cohort, this was then transferred into Microsoft Excel for further analysis. Descriptive statistics are presented throughout for demographic and outcome data. 

Minimal clinically important change (MCIC) scores were interrogated for all MOXFQ domains at each postoperative measurement point (6 months and 12 months). MCIC is an anchor based estimate of score change where a patient notices an actual, rather than statistical improvement in their foot health status. In the context of foot surgery, Dawson et al. [21] determined the MCIC estimate to be a 13-point score change across each of the 3 domains. 


All 20 patients completed preoperative MOXFQ questionnaires, 19 patients returned at six months and 18 patients returned at 12 months to complete postoperative MOXFQ, and patient satisfaction PSQ-10 questionnaires. Two patients (10%) were lost to follow-up at 12 months but the remaining 18 patients did return for a final review at a mean 18.95 months (range 11- 24 months). Only one case was a revision procedure following moderate 1st MTPJ degeneration after a hallux valgus correction with scarf and Akin osteotomies. MOXFQ scores improved at 6 months and a further improvement was recorded at 12 months across all three domains compared to baseline scores (See Figure 1). The MOXFQ score change at both 6 and 12 months exceeded the threshold for MCIC demonstrating an actual improvement in patients HRQOL (See Table 2). 

Demographics Measure Number Percentage %
ASA 1 8 40
ASA2 12 60
Female 17 85
Male 3 15
Mean Age 51 years
Age Range 35-72
Joint involvement Hallux Rigidus stage 2* 8 47
Hallux Rigidus stage 3* 8 47
Hallux Rigidus stage 4* 1 6
Lesser Metatarsal II** 2 67
IV** 1 33

Table 1 Patients diagnosed with lesser MTPJ degenerative disease were graded according to the Smillie classification system for Freiberg’s infraction. *Hallux Rigidus Classification (0-IV) Coughlin & Shurnas (2003). **Lesser Metatarsal – Smillie Classification (I-V).

Domain Pre-op 6/12 


Score change 12/12 


Score Change Minimal clinical important difference
Walking 67 47 20 33 34 16
Pain 80 45 35 32 48 12
Social  60 33 27 20 40 24
Mean PSQ-10 76 78

Table 2 Six- and 12-month follow-up: Summary of Mean MOXFQ and PSQ10 Scores.

Sequelae Number Percentage %
6 Months
Joint Pain & Stiffness 12 60
Swelling 2 10
Transfer Metatarsalgia 1 5
Implant failure revised to joint destructive procedure  3

1st MTPJ Arthrodesis

1st MTPJ Primus Implant

2nd MTPJ Interplex Rod

12 Months 
Joint restriction 4 20
Joint Pain & Stiffness 5 25
Implant failure revised to joint destructive procedure  2

1st MTPJ Arthrodesis 


Table 3 Six- and 12-month complications.

Figure 1 MOXFQ scores improved at 6 months and a further improvement was recorded at 12 months across all three domains compared to baseline scores.

Table 2, illustrates patient satisfaction scores recorded using the PSQ10 questionnaire at both 6 and 12 months, scores did meet the benchmark suggested for UK podiatric surgery of 75 and above [22]. Further descriptive data from the PSQ10 questionnaires demonstrated that at 6 months post operation, 65% of patients felt that their original complaint was now better or much better, while 4 patients (20%) felt their foot condition had deteriorated. At 12 months, 60% of patients felt better or much better and only 1 patient (5%) reported a deterioration in their foot condition. At 6 months 80% of patients felt that their original expectations from before surgery had been met or partly met and 95% reported they would be prepared to have surgery performed under the same conditions again, this reduced to 75% and 80% respectively by 12 months.

Within the first six months following surgery 12 patients, 60% of the cohort, had returned complaining of joint pain and stiffness and subsequently underwent MUA with intra-articular corticosteroid injection. Marked swelling was noted in two patients (10%), and one patient (5%) developed transfer metatarsalgia, there were no episodes of suspected or proven post-operative infection (See Table 3). Three implants failed and had to be revised to a joint destructive procedure in the first 6 months, this equated to 15% of the cohort and by 12 months the revision rate had risen to 25% a significantly higher figure than reported by the MOTION study. A further 25% of patients continued to experience pain and stiffness within the joint, and only 20% noticed an improvement in joint ROM at 12 months. Table 3 details the full list of complications recorded at 6 and 12 months following surgery.


In our study population, initial results for SCHIA in the surgical treatment of advanced MTPJ arthritic degeneration were suboptimal and not as good as previous studies stating positive outcomes in over 90% of patients [9-12]. Although validated PROMS demonstrate a subtle improvement in HRQOL and patient satisfaction at 6 months and 12 months, our results were not convincing and both complication and revision rates were high compared to the MOTION study group [9-11]. To our knowledge this is the first study to indicate suboptimal results for the SCHIA. 

Level I evidence from Baumhauer et al., demonstrated extremely promising results for the SCHIA. They found that clinical outcomes of pain, function and safety were equivalent to the gold standard 1st MTP joint arthrodesis, for treating advanced hallux rigidus at two-year follow-up, with the added advantage of improving joint dorsiflexion [9]. Two subsequent studies carried out by the MOTION study group showed these positive outcome scores were consistently maintained at 5.8 years when compared with those observed at two years [9-11]. The improvements from baseline exceeded the MCID for each outcome measure for the vast majority of patients at 5.8 years (90.5%-97.2%) [11]. 

It is difficult to directly compare our results to the previous studies as the study design, methodology and outcomes are dissimilar, however, it is still apparent that our early outcomes for SCHIA did not fare as well as the original study [9]. Within the first six months following surgery 12 patients (60% of the cohort) returned complaining of joint pain and stiffness and subsequently underwent MUA with an intra-articular corticosteroid injection. In a recent retrospective study of 60 patients undergoing 64 SCHIA’s for the management of stage 2-4 hallux rigidus yielded an overall neutral patient satisfaction, mild pain and dysfunction at an average follow up of 15.2 months [23]. Over half of their cohort had at least one injection of corticosteroid for joint pain postoperatively at 2 or more months after surgery, for a total of 79 injections and 82% of injections were given within the first year. As a consequence of our initial results we now routinely counsel patients about the risk of persistent pain and swelling and the potential need for a manipulation under anaesthetic with intra-articular corticosteroid injection within the first 6 months of surgery. 

The MOTION study noted few safety concerns at 2 or 5 years, with overall survivorship of the SCHIA reported to be 84.9% at 5.8 years [11]. Our study noted a lower implant survivorship of 75% at 12 months. Surgical revision rate was therefore high in-comparison with 25% of the cohort having the implant removed and converted to a joint destructive procedure as a result of persistent or recurrent joint pain and stiffness.

A 9.2% surgical revision rate and conversion to a 1st MTPJ arthrodesis at 24 months was reported by the MOTION study. Daniel et al., showed an impressive 96% implant survivorship with only one implant having to be removed and converted to arthrodesis [10]. It should be noted that this was a small subgroup of patients taken from the MOTION study followed up at 5 years, and therefore may not be a true representation of the original cohort. Glazebrook et al., did publish the complete midterm results for the MOTION study and, although there was a loss to follow-up of 17%, they reported a more realistic implant survivorship of 84.9% by 5.8 years [11]. Cassinelli et al., also found excellent implant survivorship of 92%, however they had a reoperation rate of 20% in their short-term follow-up study [23]. A third of patients underwent magnetic resonance imaging (MRI) postoperatively due to persistent pain. Revision surgery included implant removal and conversion to arthrodesis (5 patients), lysis of adhesions (4 patients), Moberg osteotomy (1 patient), and implant exchange with bone grafting for impinging soft tissue or implant subsidence (3 patients). It was not made clear if postoperative MRI imaging was helpful in determining if reoperation was necessary and whether it played a part in deciding whether to retain or remove the implant, but it is clear that this would have added a further expense to an already expensive procedure. A longer-term follow-up of these patients would be useful to evaluate the reoperation success rate and to determine how implant removal and arthrodesis compared with the less aggressive procedures, including implant exchange. All of our revision surgeries involved a joint destructive procedure of either MTPJ arthrodesis or total implant arthroplasty, intraoperatively in all cases the implant was found to have subsided below the cortical bone of the metatarsal head with resultant bony contact between the proximal phalanx and metatarsal head. Due to the advanced arthritic degeneration and the fact that the SCHIA had already failed, we felt that a joint destructive procedure would yield the most reliable surgical outcome for these patients.

Rothermel et al., carried out a systematic review of the available literature and compared the cost of SCHIA and 1st MTPJ arthrodesis. The total direct cost of MTPJ arthrodesis was $3632, using a conservative failure rate of 9.2% with subsequent conversion to MTPJ arthrodesis, the total cost of SCHIA was $4565. They concluded that significantly higher inclusive costs were associated with the SCHIA, and sensitivity analysis revealed that MTPJ fusion was more cost-effective even if the failure rate increased to 15% and SCHIA failure rate was 0% [24].

Other than secondary surgeries carried out for implant failure, the original prospective randomised study does not provide any other information on postoperative complications, nor does it give an explanation for implant failure [9]. Cassinelli et al., thought that implant failure was largely a result of the implant subsiding, they recommended only using SCHIA in patients with adequate bone stock and that leaving the implant prominent may reduce the risk of subsidence [23]. Given our study demographics that included 85% women with a mean age of 51, hence a high portion of our cohort were at high-risk of osteoporosis. This may offer some explanation for the high rate of implant subsidence and our high implant failure rate compared to other studies with a lower female to male ratio and age comparison [9-11]. 

In our study, all patients underwent six-month postoperative x-ray evaluation, typical findings showed marked narrowing of the joint space, proximal impaction of the synthetic cartilage implant into the head of the metatarsal and there was significant arthritic involvement of the sesamoid apparatus. Daniels et al., reviewed 23 of the 27 patients radiographs at five-year follow-up. They reported no signs of implant loosening or subsidence and no evidence of implant wear. Radiographs did show signs of further arthritic joint degeneration compared to baseline films, however none required further surgery [10].    

One of the main reasons patients choose a joint implant procedure over an arthrodesis is to maintain or improve function and joint ROM [2,3,4,8,9,10,11,25]. The MOTION study demonstrated a mean improvement of 27.3% in 1st MTPJ dorsiflexion at 24 months, these improvements in dorsiflexion were maintained at 5.8 years following surgery compared to baseline results [9-11]. In our study 60% of patients noticed an improvement in symptoms at 12 months, however only 20% of patients noticed an improvement in joint ROM, 80% had no improvement or a deterioration in joint ROM with the SCHIA. Cassinelli et al., reported that 14% of patients noticed a restriction in 1st MTPJ ROM postoperatively and were provided with a dynamic splinting device to aid postoperative rehabilitation and improve joint ROM. A further 19% were found to have restricted 1st MTPJ ROM intraoperatively and in these patients in addition to releasing the sesamoids they also added a Moberg dorsiflexion osteotomy of the proximal phalanx in an attempt to restore normal MTPJ ROM and kinematics, none of these patients complained of restricted joint ROM at short-term follow-up [23]. 

Another explanation for our suboptimal results may at least in some part be due to technical error. We feel that whilst being described as a joint resurfacing implant, in actual fact the synthetic cartilage implant has more of a buffer effect and if the Implant is inserted too deep within the metatarsal head there is a greater risk of subsidence due to the softer trabecular bone found in the metatarsal diaphysis. Leaving the Implant significantly prouder will not only reduce the risk of subsidence, as stated by Cassinelli et al., but also distend the joint and increase the implants buffer effect. We found that SCHIA limited the size of the dorsal metatarsal head exostectomy that could be taken, subsequently dorsal joint impingement was more likely, leading to reduced joint dorsiflexion and increased pain at end range of motion. Reducing the size of the implant or placing the implant more plantarly within the metatarsal head may address this issue, further studies on implant position and subsidence are needed. Finally, in advanced hallux rigidus, the sesamoids are often involved, showing significant hypertrophy on x-rays and clinically being ankylosed to the base of the metatarsal head, causing joint pain and stiffness. In our experience despite releasing the sesamoids intraoperatively, SCHIA does not address the sesamoid apparatus and continued plantar joint pain and stiffness was a recurrent issue in our cohort at 6 and 12 month follow-up. 

Limitations of this study lie with its single center retrospective design, small sample size, and short- term follow up, which undermines the reliability of these results. Due to the small cohort of patients we were unable to perform any statistical analysis and instead used descriptive analysis. The low patient numbers were because we quickly stopped using SCHIA to treat advanced arthritic degeneration of the MTPJ’s, as a consequence of cost and suboptimal results noted at early follow-up. We are unable to comment regarding mid to long-term results and perhaps patient satisfaction rates, complications and revision rates may all improve with time in our study population and measures have already been put in place to follow these patients up at 3 and 5 years. 

We acknowledge that combining the outcomes of the 1st MTPJ and lesser MTPJs may be a methodological error, as they are different pathologies and there is no equivalent of the 1st MTPJ sesamoid apparatus in the lesser MTPJs and, moreover, it is not typically salvageable by arthrodesis. However, reviewing the conditions separately would have reduced the numbers in the study further and we do not believe that combining the results in this case has detracted from the purpose of this study, which was to present our initial experience including patient reported outcomes and complications relating to MTPJ SCHIA. 

In conclusion, our initial results for the SCHIA were suboptimal, complication and revision rates were high and did not compare well with previous results published by the MOTION study group. From our experience, we would recommend judicious use of the SCHIA in the surgical treatment of patients with advanced MTPJ arthritic degeneration. We feel that further work around patient selection, implant positioning and subsidence is necessary. 


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