Tag Archives: Foot

Emphysematous osteomyelitis of the foot: A case report

by Igor Dukarevich, DPM1*; Victoria Chirman, DPM2; Mahin Siddiqui, DPM3

The Foot and Ankle Online Journal 13 (3): 4

Emphysematous osteomyelitis is a rare life-threatening infection requiring early recognition and immediate surgical intervention. The condition is usually caused by anaerobes, gram negative rods, or is polymicrobial. It presents in immunocompromised hosts with comorbidities such as diabetes mellitus, thalassemia major, sickle cell disease, alcohol abuse, and exogenous immunosuppression. This infection can be either of contiguous or hematogenous spread, and has been previously reported in both the axial and the appendicular skeleton. Intraosseous gas is frequently overlooked on plain radiographs but is easily diagnosed by CT scan. We describe a case of direct extension emphysematous osteomyelitis involving the foot of a 52-year-old male with poorly controlled diabetes mellitus type 2. We emphasize the need for a high index of suspicion, early diagnosis via CT scan, and immediate surgical intervention. We also underscore the utility of the Symes amputation, used in our case as an alternative to transtibial amputation for diabetic limb salvage.

Keywords: emphysematous, foot, gas, intraosseous, osteomyelitis

ISSN 1941-6806
doi: 10.3827/faoj.2020.1303.0004

1 – Podiatry Residency Director, Loretto Hospital, 645 S Central Ave, Chicago, IL 60644
2 – Podiatry Resident, Loretto Hospital, 645 S Central Ave, Chicago, IL 60644
3 – Podiatry Resident, Loretto Hospital, 645 S Central Ave, Chicago, IL 60644
* – Corresponding author: dukarevichi@gmail.com

Emphysematous osteomyelitis is a rarely-reported condition, previously not described in the podiatric literature.  It was first noted by Ram PC, et al., in 1981, when a CT scan demonstrated gas within the medullary cavity of the involved bone [1]. In their case series, all plain radiographs were negative and there was no clinical suspicion of the severity of the infection until a CT scan was obtained. The CT scan findings significantly changed the management of the patients.

Since the initial report, the majority of the cases described have been limited to the axial skeleton with suspected hematogenous spread [2]. A hand-full of cases have been described in the appendicular skeleton, both of contiguous and hematogenous extension, with emphysematous osteomyelitis presenting in the femur, the tibia, and the foot. In the majority of the reported cases, the patients have multiple comorbidities including diabetes mellitus, use of immunosuppressive medication, malignancy, alcohol abuse, thalassemia major, or sickle cell disease [2-4]. In many cases, the X-rays were negative for soft tissue gas and the diagnosis was made only with prompt CT imaging [1].  We report a case of contiguous spread emphysematous osteomyelitis in the foot, emphasizing the need for a high-index of suspicion, prompt advanced imaging, and aggressive treatment for this rare but life-threatening condition.

Case Report

A 52-year-old African American male, with a past medical history of polysubstance abuse, poorly controlled diabetes mellitus type 2, iron deficient anemia, seizure disorder, peripheral neuropathy, history of chronic ulcerations, had underwent treatment in our facility from 12/2018 through 01/2019 for emphysematous osteomyelitis of the right foot.  The patient presented to the emergency department on December 6, 2018 with a chief complaint of right foot pain and swelling.

Figure 1 Clinical appearance.

He previously underwent a partial right first ray amputation at a different hospital in 08/2018, with delayed healing of the surgical wound.  The patient was unable to provide a detailed history of his condition at the time of the admission. The patient had no known drug allergies. Family history was non-contributory. Review of systems was unremarkable, with exception of the chief complaint.

On examination, the patient was noted to be a well-nourished, well-developed male in no apparent distress. The vital signs were stable, with the exception of a low-grade fever at 99.4 degrees Fahrenheit and a pulse of 126 bpm.  Significant findings on the physical exam included moderate edema and erythema to the right foot. A partially healed amputation site of the first ray of the right foot was appreciated with a necrotic ulceration on the dorsum of the foot probing directly to bone and tendinous structures. Mild serous drainage was noted from the wound, but no obvious fluctuance, purulence, or soft tissue crepitus was appreciated (Figure 1).  Pedal pulses were faintly palpable bilaterally with capillary refill times less than four seconds to the remaining digits of the right foot. Neurologically, light touch and sharp/dull sensation was diminished distal to the mid-leg level of bilateral lower extremities.

Radiographs of the right foot were obtained and were suggestive of osteomyelitis of the second metatarsal base, however no evidence of significant osseous destruction or soft tissue gas was noted. Vascular calcifications were appreciated. (Figure 2). Significant neutrophilic leukocytosis was noted with WBC at 14.4. Blood cultures were positive for Strep. Pyogenes.  Lactic acid was 2.1.

Figure 2 Radiographs of the right foot, suggestive of osteomyelitis of the second metatarsal base.

Figure 3 CT of foot, showing small foci of subcutaneous gas were also noted in the tissues.

The last HbA1C was 13.7%. Albumin was 1.4. Deep wound cultures were obtained at the time of admission. The patient was started on IV fluids and Vancomycin and transferred to the hospital loor for further evaluation and management. Infectious disease and a podiatry consult was requested.

Infectious disease and podiatry recommended the addition of piperacillin/tazobactam and metronidazole to broaden the antibiotic coverage. A CT scan of the right foot was obtained. The CT scan demonstrated multiple foci of intraosseous gas in the midfoot including navicular, cuboid and cuneiform bones, as well as the bases of second, third, fourth, fifth metatarsals. Small foci of subcutaneous gas were also noted in the tissues (Figure 3). The findings were consistent with the “pumice stone” pattern previously reported by Small JE, et al., and diagnostic for emphysematous osteomyelitis.

Given the findings, an emergent incision and drainage of the right foot with a guillotine amputation at the Chopart level was performed. Clearance fragments were obtained from the distal talus and the calcaneus. Following surgical intervention, the patient continued to improve with resolution of leukocytosis and fever. Blood cultures were negative.  Wound culture results revealed growth of Staphylococcus Aureus, Klebsiella, Enterobacter Aerogenes, and Streptococcus Pyogenes Group A. Empiric antibiotic therapy was narrowed to clindamycin and penicillin, per sensitivity report and infectious disease recommendations.

Figure 4 Radiographs after Chopart level amputation.

Arterial doppler studies of the lower extremities confirmed no significant peripheral arterial disease of the right lower extremity with biphasic waveforms throughout. Follow-up radiographs and CT scan demonstrated no proximal spread of emphysematous osteomyelitis (Figure 4). Pathology analysis of the resected foot displayed skin and subcutaneous tissue showing necrosis and gangrene; bone with underlying acute and chronic osteomyelitis. Clearance fragments from the distal talus and calcaneus were negative for osteomyelitis.

In the subsequent days revision of the amputation and delayed primary closure was performed. Due to fair right lower extremity arterial perfusion, a decision was made to attempt distal limb salvage with a Syme’s amputation, as opposed to a below-the-knee amputation. A Syme’s amputation was performed per standard technique and the patient tolerated the procedure well (Figure 5). The remaining hospitalization course was uneventful and the amputation flap was healing well. The patient was discharged to an extended care facility. The patient missed his first two postoperative appointments and was seen in the outpatient clinic for follow-up about one month after the surgery.  The patient was noted to have partial dehiscence and necrosis of the lateral one-third of the incision with the remainder of the incision healing well. The patient was readmitted for IV antibiotic therapy, vascular evaluation, and debridement.   An angiogram of the right lower extremity confirmed no significant disease in the bilateral common internal and external iliac arteries and there was noted to be a two-vessel runoff to the foot without any significant disease. The patient underwent further debridement and wound care. The patient had successful healing of the Syme’s amputation stump via secondary intention without further setbacks.

Figure 5 Radiographs after Syme’s level amputation.


Emphysematous osteomyelitis is a rare but potentially life-threatening condition [1-5]. About thirty cases have been described thus far in literature; the majority presenting with predominantly hematogenous spread in the spine, pelvis, and hip [1-5]. Only three cases have been previously described affecting the foot [2-4].

Our case of emphysematous osteomyelitis in the foot was similar in presentation to those previously reported by Mautone et al and Abdelbaki et al [3-4].  The spread of the infection was contiguous from a chronic ulceration persisting from delayed healing of a partial foot amputation. Khanduri et al reported the only case of hematogenous spread to the foot, with the source likely being a urinary tract infection [2].

As in the previously reported cases of emphysematous osteomyelitis of the foot, our patient was immunocompromised with multiple comorbidities. Clinical findings and X-rays were fairly benign and underestimated the extent of the infection. A prompt CT scan allowed for accurate diagnosis and appropriate emergent treatment. The finding of intraosseous “pumice stone” pattern of gas formation on CT scan was diagnostic for emphysematous osteomyelitis [5]. The CT scan allowed for clear visualization of the extent of the infection and helped to guide the level of the amputation.

As in other reported cases of emphysematous osteomyelitis, the infection in our case was polymicrobial. As such, empiric antibiotic therapy should be broad-spectrum and should include anaerobic coverage, with later narrowing based on culture and sensitivity results. As with gas gangrene of the soft tissues, the primary treatment for emphysematous osteomyelitis is emergent surgical debridement with amputation of all infected structures. Input and intervention from internal medicine, interventional cardiology, and infectious disease specialists is also critical in the successful management.

As with other diabetic foot infections, the long-term treatment goal should be distal limb salvage with rapid return to functional activity [7]. Previous studies have demonstrated the utility of the Syme’s amputation, with advantage of a more natural gait resulting in decreased metabolic expenditure and cardiac stress [6-7]. The literature also suggests lower morbidity and mortality rates after a Syme’s amputation in comparison to transtibial amputations [6-7]. We believe that it remains a viable alternative for limb salvage.

We describe a case of emphysematous osteomyelitis, previously not reported in the podiatric literature, managed with a Syme’s amputation. We emphasize the need for a high-index of suspicion in immunocompromised patients with long-standing post-surgical ulcerations, as well as early use of advanced imaging. The use of a CT scan helps to determine the extent of infection and the level of amputation. We also note that the Syme’s amputation remains an alternative to transtibial amputations for distal limb preservation. Severe diabetic foot infections such as emphysematous osteomyelitis, are a challenging entity, requiring prompt intervention by a multidisciplinary team to achieve a successful outcome.


  1. PC Ram, S Martinez, M Korobkin, RS Breiman, HR Gallis, JM Harrelson. CT detection of intraosseous gas: a new sign of osteomyelitis. AJR Am J Roentgenol, 137 (1981), pp. 721-723
  2. Sachin Khanduri, Meenu Singh, Aakshit Goyal, Simran Singh. Emphysematous osteomyelitis: Report of two cases and review of literature. Indian Journal of Radiology and Imaging. 2018;(1):78.
  3. Mautone M, Gray J, Naidoo P. A Case of Emphysematous Osteomyelitis of the Midfoot: Imaging Findings and Review of the Literature. Case Reports in Radiology. January 2014:1-4.
  4. Abdelbaki A, Bhatt N, Gupta N, Li S, Abdelbaki S, Kumar Y. Emphysematous osteomyelitis of the forefoot. Proceedings (Baylor University Medical Center). 2017;31(1):100-101.
  5. Small JE, Chea P, Shah N, Small KM. Diagnostic Features of Emphysematous Osteomyelitis. Curr Probl Diagn Radiol. 2018 Jun 1
  6. Pinzur MS. Amputation level selection in the diabetic foot. Clin Orthop. 1993; 296:68-70.
  7. Yu G, Meszaros A, Schinke T. Syme’s amputation: A retrospective review of 10 cases. Podiatry Institute Update, Chapter 14, Podiatry Institute, Tucker, GA, 2005, pp. 78–88.



Rare, non-displaced, sagittal plane fractures of the navicular body: A report of two cases

by Rachelle Randall, DPM1*, Lawrence M. Fallat, DPM, FACFAS2

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

Cases of non-displaced, sagittal plane fractures of the navicular are most commonly seen as stress fractures. Previous literature suggests that the mechanism of injury of most high impact falls have shown significant dislocation of the navicular counterparts or comminution to other structures of the foot. We present two rare cases of high impact injury creating sagittal plane fractures through the navicular body without any dislocation of the navicular or trauma to any surrounding structures. Two patients had similar high impact falls and mechanisms of injury leading to mirrored navicular fracture patterns. Surgical correction was performed in both patients. At three months postoperative both patients were clinically pain free in normal shoe gear, and radiographically healed. At one year postoperative both patients had maintained correction and had returned to full activity prior to injury, pain free. Both of these cases resulted from falls with a longitudinal compression force and an axial loading mechanism, generating these non-displaced, sagittal, navicular body fractures. Due to the avascularity of the body of the navicular and age of the patients, surgical correction of the fracture site was performed to help prevent non-union, avascular necrosis, displacement and future arthritic changes. Both patients had favorable surgical outcomes. There is a need to denote this mechanism of injury and corresponding fracture pattern within the current literature.

Keywords: bone, fall, foot, mechanism, midfoot, stress, trauma

ISSN 1941-6806
doi: 10.3827/faoj.2020.1303.0002

1 – Resident, Postgraduate Year 2 – Beaumont Health Wayne, Podiatric Foot and Ankle Surgical Residency, Beaumont Hospital Wayne, Wayne, MI 48184, USA
2 – Director – Beaumont Health Wayne, Podiatric Foot and Ankle Surgical Residency, Beaumont Hospital Wayne, Wayne, MI 48184, USA
* – Corresponding author: rachellelrandall@gmail.com

Isolated fractures of the navicular bone are rare [1]. The navicular plays an essential role in the medial longitudinal arch and the stability of the midfoot structure as the keystone [2]. Loss of the height or alignment of the keystone can result in loss of 90% or greater of complex hindfoot motion [3]. Classification systems have been derived for fractures of the navicular and corresponding midfoot. Sangeorzan, et al., [4] classified displaced, intra-articular fractures of the tarsal navicular, while Watson-Jones [5] classified multiple navicular fracture patterns including the stress fracture. Though there have been classifications of fracture patterns, the discussion of the mechanism of action and injury is rarely researched and cited. Main and Jowett [6] were the first authors to describe multiple potential mechanisms of action of the navicular fracture. Rymaszewski and Robb [1] in 1976, proposed one revisional mechanism in a later case report and finally, Rockett and Brage [7] in 1997 assessed navicular fractures on Computerized Tomography reviewing five different fracture patterns and proposed another potential mechanism of injury not previously discussed in the literature.

Figure 1 Preoperative radiograph of right foot in Patient 1.

Main and Jowett is still the most cited and well recognized classification system of navicular fracture mechanisms. This classification system was based solely on assessment of radiographic appearance of midtarsal fractures. It was developed by considering the direction of the fracture, the disruption of joints and malalignment of the foot. As stated by Main et al. tarsal navicular body fractures result from axial loading forces that occur frequently when falling from a height. The longitudinal compression forces on the talus lead to compression of the navicular into the cuneiforms, and the navicular to absorb the shock of impact [6].

We present two cases of high impact injury causing sagittal plane fractures through the navicular body, without dislocation of the navicular or surrounding structures.

Figure 2 Eight weeks postoperative radiograph of right foot in Patient 1.

Our case report reveals fracture patterns that appear consistent with stress fractures [8] while the mechanism of action correlates to dislocated, comminuted, corresponding fracture patterns. This mechanism of injury and corresponding fracture pattern has yet to be recognized in the current literature or described in any classification system.

Case Report 1

A 17-year-old male, with no significant past medical history, was treated from 08/2017 to 06/2019. He first presented to the emergency department after a bike riding accident. The patient reported he was 10-15 feet in the air doing a bike trick when he fell and landed directly on his right foot. He stated that he landed with his foot being pointed downward (plantarflexed) and landing on the ball of his foot. The patient admitted to continuing to ride his bike for 20 minutes after initial injury until the pain became too severe. On physical exam the patient had midfoot edema but no ecchymosis or visible deformity present.

Plain radiographs were taken revealing a non-displaced, fracture in the sagittal plane through the body of the navicular. No comminution or dislocation was noted (Figure 1). The patient had surgery three weeks from the initial injury date. He was placed on the operating table in the supine position with an ankle tourniquet inflated. After IV sedation and local anesthesia, the fracture site was reduced percutaneously with a point-to-point clamp and a guide wire was placed across the fracture site from medial to lateral. Guide wire alignment and fracture reduction were then assessed with fluoroscopy imaging intra-operatively. Next, a small stab incision was made on the medial aspect of the navicular and a single 4.0 mm cannulated, cancellous, partially threaded screw was placed across the fracture site. The skin was closed with 3-0 nylon suture.

The patient was placed in a CAM boot to remain non-weight bearing with use of crutches. The sutures were removed at four weeks and the patient was permitted partial weight-bearing in a CAM boot at this time. He was seen again at eight weeks with zero out of ten pain. The radiographs revealed bony callus with cortical healing across the fracture site (Figure 2). The patient was advised to continue use of the CAM boot for two more weeks and then transition into normal shoe gear. The patient started his wrestling season at ten weeks post-operatively, and he was pain free. The patient was seen at three months postoperatively and had been ambulating in supportive shoe gear without pain and participating in wrestling and snow-boarding. The patient was evaluated again 12 months from initial surgery date and remained actively participating in sports and daily activities pain free.

Case Report 2

The second patient was a 26-year-old female, with no significant past medical history, treated from 10/2017 to 05/2019. She presented to our office after being referred from an orthopedic surgeon one week after her initial injury. The patient stated that she fell down a flight of stairs and landed on the ball of her left foot. On physical exam she had no apparent deformity, but localized edema at the midfoot. Plain radiographs showed a complete, non-displaced, sagittal plane fracture through the body of the navicular (Figure 3).

Surgery was performed one week after the initial injury date. She was placed on the operating table in the supine position with an ankle tourniquet inflated. After IV sedation and local anesthesia, the fracture site was reduced percutaneously and stabilized with a point-to-point clamp. Two guide wires were placed from medial to lateral, percutaneously, crossing the fracture site. A small stab incision was then made medially and two 4.0 mm cannulated, partially threaded screws were placed across the fracture site. Fluoroscopy imaging was performed intra-operatively confirming reduction of the fracture site and alignment of the screws. The skin was closed with 3-0 nylon.

The patient was placed in a CAM boot to remain non-weight bearing with use of crutches. Sutures were removed at four weeks postoperatively and the patient was permitted to partial weight-bear in CAM boot at this time. The patient was seen at eight weeks with two out of ten pain. The radiographs revealed bony callus and healing across the fracture site (Figure 4). She was advised to slowly transition out of the CAM boot over the following two weeks. The patient was evaluated again at three months postoperatively and she was playing with her kids pain free at this time. The patient was seen again at 12 months postoperatively and she continued to remain asymptomatic and ambulating in normal shoe gear and full activity.

Figure 3 Preoperative radiograph of left foot in Patient 2.


These isolated fracture patterns with associated mechanisms of action are rarely cited in literature. Cases of non-displaced, sagittal plane fractures are most commonly seen as stress fractures. Most high impact falls have shown significant dislocation of the navicular counterparts or surrounding structures [9]. Although both cases resulted from high energy falls with longitudinal compression and an axial loading mechanism, they exhibited non-displaced, sagittal, navicular body fractures, without dislocation or comminution. This fracture pattern and corresponding mechanism of injury does not fit into any previously cited case.

Figure 4 Eight weeks postoperative radiograph of left foot in Patient 2.

Main and Jowett [6] go into great detail when discussing mechanism, classification and treatment of midtarsal joint injuries. They divided the midtarsal injuries into five major categories when assessing mechanism and fracture pattern. The two navicular injuries presented do not fit into any current classification of mechanism of injury and corresponding fracture pattern. The study by Rocket and Brage [7] most closely correlates to our findings. In their 4th patient, the radiograph revealed what appeared to be a non-comminuted, sagittal plane fracture through the body of the navicular. After computed tomography was performed they found a corresponding large plantar fragment suggestive of comminution. It is also important to note the patient had multiple calcaneal fractures from the corresponding injury as well. As Sangeorzan, et al., classified all of their fracture patterns as displaced fractures of the navicular, our fractures only revealed a sagittal plane fracture without dislocation or comminution [4]. The majority of high impact navicular fractures are associated with either dislocation of navicular components or multiple bone injuries of the foot.

Isolated fractures through the body of the navicular lack significant blood flow [10] and frequently require internal fixation to ensure higher healing probabilities. Due to the avascularity of the body of the navicular [3] and young age of patients, it was appropriate to have surgical correction of the fracture site to help prevent non-union, avascular necrosis and future displacement or arthritic changes. Due to the lack of dislocation and ease of fracture site approximation, the ability to reduce and fixate these fractures percutaneously was both imperative and beneficial. Both patients having suffered high impact falls with minor osseous injury, had excellent surgical outcomes.

We propose the concept that there is potentially another mechanism of injury with corresponding fracture patterns, not previously cited in literature. The foot is accepting forces in an axial loading mechanism while the navicular is able to completely absorb the forces of the impact due to the talus and corresponding cuneiforms compressing at equal energies. These cases resulted from longitudinal compressive forces through the foot without any dislocation and allowing solely the navicular bone to absorb their impact.


  1. Rymaszewski, L. A., & Robb, J. E. Mechanism of fracture-dislocation of the navicular: brief report. The Journal of bone and joint surgery. British volume, 70(3), 492-492, 1988.
  2. Nyska, M., Margulies, J. Y., Barbarawi, M., Mutchler, W., Dekel, S., & Segal, D. Fractures of the body of the tarsal navicular bone: case reports and literature review. The Journal of trauma, 29(10), 1448-145, 1989.
  3. Buckley R, Sands A, AO Surgery Reference, https://surgeryreference.aofoundation.org/orthopedic-trauma/adult-trauma/midfoot/
  4. Sangeorzan, B. J., Benirschke, S. K., Mosca, V. E. A., Mayo, K. A., & Hansen, J. S. Displaced intra-articular fractures of the tarsal navicular. The Journal of bone and joint surgery. American volume, 71(10), 1504-1510, 1989.
  5. Watson-Jones, Reginald. Fractures and Joint Injuries. Baltimore, The Williams and Wilkins Co. Ed. 4, Vol. II, p. 900, 1955.
  6. Main, B. J., & Jowett, R. L. Injuries of the midtarsal joint. The Journal of bone and joint surgery. British volume, 57(1), 89-97, 1975.
  7. Rockett, M. S., & Brage, M. E. Navicular body fractures: computerized tomography findings and mechanism of injury. The Journal of foot and ankle surgery, 36(3), 185-191, 1997.
  8. Mallee, W. H., Weel, H., van Dijk, C. N., van Tulder, M. W., Kerkhoffs, G. M., & Lin, C. W. C. Surgical versus conservative treatment for high-risk stress fractures of the lower leg (anterior tibial cortex, navicular and fifth metatarsal base): a systematic review. Br J Sports Med, 49(6), 370-376, 2015.
  9. Mathesul, A. A., Sonawane, D. V., & Chouhan, V. K. Isolated tarsal navicular fracture dislocation: a case report. Foot & ankle specialist, 5(3), 185-187, 2012.
  10. Torg, J. S., Pavlov, H., Cooley, L. H., Bryant, M. H., Arnoczky, S. P., Bergfeld, J., & Hunter, L. Y. Stress fractures of the tarsal navicular. A retrospective review of twenty-one cases. JBJS, 64(5), 700-712, 1982.


Chronic ulceration following surgical excision of a Morton’s neuroma due to an underlying arteriovenous malformation of the foot

by H Emmerson MBBS1, T Howard BMBS2*, M Wilkinson FRCS (Ortho)3, RS Ahluwalia FRCS (Tr & Orth)4

The Foot and Ankle Online Journal 12 (3): 4

An arteriovenous malformation (AVM) of the foot is a rarely encountered clinical pathology.  Arteriovenous malformations are most commonly found in the brain and lungs, and when found in the lower limbs, are usually in the pelvis or thigh and not the foot or ankle.  We describe a rare malformation that complicated surgical removal of a Morton’s neuroma, with chronic ulceration and failed wound healing. Successful treatment with conservative measures ensured full recovery. We believe all health care professionals should be aware of this pathology and consider it as a cause of delayed healing.

Keywords: arteriovenous malformation, foot, chronic ulceration, delayed wound healing

ISSN 1941-6806
doi: 10.3827/faoj.2018.1203.0004

1 – Trauma & Orthopaedics, King’s College Hospital, London
2 – Foundation Doctor, Trauma & Orthopaedics, King’s College Hospital, London
3 – Trauma & Orthopaedics, King’s College Hospital, London
4 – Consultant Surgeon, Trauma & Orthopaedic, King’s College Hospital, London
* – Corresponding author: Theodore.howard@nhs.net

We present the case of a 38-year-old bus driver who presented with a non-healing ulcer of the left foot following the removal of a Morton’s neuroma 10 months prior at a community allied medical institution unrelated to ours. Initially, he presented in the community with ongoing focal pain in the 2nd and 3rd metatarsophalangeal joint web-space and was treated conservatively. With no resolution in pain and a slow growing mass on the dorsum of his left foot, an ultrasound scan was undertaken which confirmed a 10mm neuroma in the second web space. Two injections of steroid/local anaesthesia provided temporary relief but were subsequently followed by surgical removal of the neuroma. The wound never healed with constant ooze and further surgical debridement was undertaken in the community, accompanied by multiple courses of oral antibiotics. He had been unable to work since the neuroma removal and at 10 months post-removal he was referred for review at our institution.

He now revealed that he had had a right hip replacement at age 34 for traumatic osteoarthritis, and left testicular vein embolisation for varicocele. Physical examination of the left foot revealed a bleeding 0.5×0.5cm ulcer on the dorsum between the 2nd and 3rd web spaces (Figure 1). A dusky, pulsatile mass of 3cmx3cm was noted underlying the ulcer with surrounding hemosiderin deposition and a palpable thrill was present.  Neurovascular and musculoskeletal examination were unremarkable and there were no abnormalities to the right foot.

Figure 1 Photographs of skin appearances of the left foot 1 week after presentation. Dorsum – visible features are a healing ulcer between the 2nd and 3rd digits, hemosiderin deposition and engorged veins. Sole – ulceration and a dusky swelling are evident.

Figure 2 CT angiogram of lower limbs demonstrating distended veins throughout the left lower limb with a leash of abnormal vessels from the knee to the foot.

Figure 3 T1-weighted MR sagittal image of the left foot demonstrating the nidus of the AVM with an engorged draining vein.

A Doppler scan was performed which detected fully patent arteries throughout the left limb with triphasic flow with a prolonged diastolic component, suggestive of hyperaemia. A computed tomography (CT) with contrast and magnetic resonance angiogram (MRA) confirmed a low flow vascular malformation (Figures 2-4).  These images revealed an enhancing soft tissue mass lesion with feeding vessels overlying the left second and third metatarsals, extending into the plantar soft tissues and a leash of abnormal vessels from the knee (Figure 2).

Angiography was undertaken demonstrating a large arteriovenous malformation (AVM) around the second toe with multiple feeding vessels (Figure 5).  This was deemed unsuitable for selective endovascular embolisation due to congestion. The patient was successfully treated with limb elevation and Class 1 compression stockings: three months later the patient reported great clinical improvement and had returned to work. 

Figure 4 [A] T1-weighted MR axial image demonstrating signal void in the engorged draining vessel (arrowed). [B] MR angiogram post-contrast demonstrating multitude of vessels (artefact present at digits).


We demonstrate the presentation of an incidental rare underlying pathology complicating a simple procedure. A high degree of clinical suspicion is needed to avoid missing this diagnosis.   Although AVMs do occur in the lower limbs, there are very few case reports in the literature of malformations arising so distally, in the foot. Therefore this is an unusual pathology that all foot and ankle practitioners should be aware of and should understand its management, as conservative treatment can provide a low cost and highly efficacious treatment.

An AVM is an abnormal collection of blood vessels allowing direct communication between arteries and veins.  The incidence is between 1-10/100000 and they are commonly found in the brain & trunk [1] and arise from congenital malformations, trauma and degenerative vascular diseases. Their growth is exacerbated by local trauma and hormonal changes, such as puberty and pregnancy [2].  Most are isolated pathologies, but multiple malformations are associated with syndromes such as Osler-Weber-Rendu, Sturge-Weber and Klippel-Trenaunay [3].  

The symptoms are dependent on locality and size and most remain small and clinically silent [3].  Symptoms occur due to effects on surrounding structures, such as bone, muscle and soft tissue and include pain, swelling, ulceration and deformity, and can be debilitating.  If left untreated, chronic ulceration may cause haemorrhage or necrosis. 

Clinical presentation can include a pigmented lesion, or birthmark, visible pulsation, or palpable thrill and engorged veins (varicosities).  Due to the local skin appearances, and rarity, the diagnosis can be mistaken for dermatological pathologies such as angiodermatitis or Kaposi’s sarcoma, or vascular tumours and chronic infection [3,4]. In this case the prolonged time to heal, ongoing ooze and bleeding from the surgical site were the findings on presentation. It is unclear whether the AVM preceded surgery but certainly was recognisable in the form of a pulsatile mass at presentation to our clinic. Surgical intervention for neuroma excision may have exacerbated the AVM, given its extensive nature.  

Initial investigation includes radiography to evaluate surrounding bony structures for erosion [3]. Color Doppler ultrasonography is a useful initial non-invasive investigation for evaluating location, size and flow of the AVM.  CT with angiography will visualise bone and tissue involvement, calcification, the presence of thrombi and size. However, magnetic resonance imaging is particularly important in providing imaging of adjacent soft tissue structures that can be involved.  Using dynamic gradient pulse sequences in MR is useful in evaluating whether the lesion is high flow or low flow [5].

Interventional therapies include ligation of feeding vessels, surgical excision, sclerotherapy or embolisation with coils/particles [6-8].  However, as demonstrated here, low-flow AVMs respond well to conservative measures, such as limb elevation and graded compression stockings.

This case is unusual as to why an extensive AVM should arise.  It is quite possible the surgical intervention for neuroma excision gave rise to the AVM or exacerbated the AVM, but given its extensive nature, it would most likely have been present prior to surgery.  It demonstrates the importance of appropriate clinical examination and high suspicion when delayed healing has complicated a simple wound. It highlights the importance of understanding wound pathology and the role of simple clinical management to healing.


  1. Kunze B, Kluba T, Ernemann U, Miller S. Arteriovenous Malformation: An unusual Reason for Foot Pain in Children. The Foot and Ankle Online Journal 2009; 2 (12): 1
  2. Huang JT, Liang MG. Vascular Malformations. Paediatric Clinics North America 2010; 57:1091-110
  3. Yu G, Brarens R, Vincent, A. Arteriovenous Malformation of the Foot: A Case Presentation. Journal of Foot & Ankle Surgery. 2004; 43(4):252-259.
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Peroneal tendinopathy in resolved Charcot foot – management with foot orthoses: A case report

by Joshua Young BSc.(Hons), MBAPO Orthotist1*

The Foot and Ankle Online Journal 12 (3): 3

This case report presents an occurrence of painful peroneal tendinopathy in a high risk diabetic foot following Charcot neuroarthropathy, managed using foot orthoses. Self-reported pain intensity was assessed using the 11-point numeric pain rating scale (NRS-11). Peak plantar pressures were assessed using the Pressure Guardian system for three conditions: 3.2mm poron inlay (control), custom foot orthosis, and custom foot orthosis with lateral wedge. Following addition of lateral wedging to the existing foot orthoses, pain reduced to a satisfactory level for the subject. Plantar pressure measurement showed that the addition of lateral wedging did not increase peak plantar pressures above 200kPa, a proposed dangerous level of pressure. Additionally, the foot orthoses still successfully reduced peak plantar pressures to below 200kPa, compared to walking without them. Peroneal tendinopathy should be considered as a possible cause of lateral ankle pain in neuropathic diabetic feet. Lateral wedging can be considered as one option to reduce pain in peroneal tendinopathy, and may not compromise the protective effect of foot orthoses in high risk feet.

Keywords: Charcot, foot, peroneal, tendinopathy, orthoses, insoles

ISSN 1941-6806
doi: 10.3827/faoj.2018.1203.0003

1 – Roehampton Rehabilitation Centre, Queen Mary’s Hospital. St George’s University Hospitals NHS Foundation Trust, London, UK.
* – Corresponding author: Joshua.Young1@nhs.net

Pain can be present even in a diabetic foot with neuropathy. Causes of pain in this group could include painful diabetic neuropathy [1–3]⁠ and Charcot neuroarthropathy (CN) or ‘Charcot foot’ [4]⁠. The cause of the pain should be determined to inform appropriate management.

Tendinopathy may also occur and cause pain in the neuropathic diabetic foot. There is a higher risk of tendinopathy in diabetes [5–7]⁠. Chronic ankle instability or ‘hind foot varus’ have been suggested as predisposing factors to developing peroneal tendinopathy [8]⁠. In theory the ground reaction force on an inverted heel deviates medially, causing an increased ankle inversion moment which must be opposed by the peroneal muscles. A more supinated foot may develop as a result of CN [9,10]⁠.

It has been proposed that the conservative management of peroneal tendinopathy may include protection, relative rest, ice, compression, elevation, medications, and rehabilitative exercise modalities (PRICEMM) in addition to foot orthoses and strengthening of ankle evertors [11]⁠. There is limited evidence on the role of foot orthoses in peroneal tendinopathy. Some work has shown that foot orthoses alter peroneal muscle activity in runners with overuse injury symptoms [12] and in adults with chronic ankle instability [13]. A foot orthosis with a 10 degree lateral wedge has been shown to increase pronation at the rearfoot and reduce the ground reaction force magnitude, suggesting increased shock attenuation by the foot and ankle[14]⁠. This case study presents a case of painful peroneal tendinopathy, which developed in a foot following CN and was subsequently managed using foot orthoses (FOs). The CARE guidelines for reporting of case studies was followed [15]. Written informed consent was obtained for the publication of the materials in this article.


The subject was a 60 year-old male with type 2 diabetes with a history of CN affecting both feet. The CN resolved 8 months previously. There was a history of superficial ulceration (Texas grade A1) [16]⁠ to the left plantar 1st metatarsal-phalangeal joint and 1st tarso-metatarsal joint, both resolved for 8 months with the use of custom foot orthoses at the time of presentation with a primary concern of right foot pain.

Clinical Findings

There was sensory neuropathy, with only 1 out of 10 sites tested with a 10g monofilament being detected (Plantar 1st and 3rd toes, plantar 1st, 3rd and 5th metatarsal-phalangeal joints bilaterally). Circulation was good with triphasic posterior tibial pulses. Passive joint ranges of motion at the foot and ankle was generally good bilaterally except reduction in midtarsal movement on the left, and reduced extension at the left 1st metatarsal-phalangeal joint (45 degrees) compared to the right (60 degrees). Foot posture was rated using the foot posture index (FPI-6)[17]⁠ as +9 on the left and +3 on the right, indicating a highly pronated foot on the left and a relatively less pronated foot on the right (Figures 1 and 2). The FPI-6 differential of 6 points exceeds both normal values for foot asymmetry and mean asymmetry reported in a CN group [10,18]. The patient presented reporting a 6 week history of right foot pain, indicating the lateral ankle. This developed despite an existing 6mm lateral flare/float addition to the right heel, intended to resist ankle inversion. Pain intensity was reported as 7/10 on the numeric rating scale (NRS-11). 

Diagnostic Assessment

Palpation of the peroneal tendons posteriorly to the lateral malleolus reproduced the pain experienced during walking. A portable ultrasound system was used by the author at this stage, indicating some fluid in the peroneal tendon sheath. 

Figure 1 Left and right feet (anterior and posterior view).

Figure 2 Lateral radiographs of left and right feet.

Figure 3 Cross sectional ultrasound image of peroneus longus showing fluid within the tendon sheath.

Figure 4 Cross sectional ultrasound image of peroneus longus and brevis using power Doppler to show hyper vascularity in the tendons.

Figure 5 Left and right foot orthoses, plantar view.

Figure 6 Right foot orthosis, posterior view.

Referral to radiology for a definitive evaluation was made, which confirmed the diagnosis of peroneal tendinopathy (Figures 3 and 4). The report identified fluid in the common peroneal tendon sheath, in keeping with tenosynovitis, and marked thickening of the peroneus brevis tendon at the insertion, in keeping with tendinosis.

Therapeutic Intervention – Orthotic Prescription

The existing FOs consisted of a 3mm thick base with 50 shore A Ethylene-vinyl acetate (EVA) at the proximal half and 30 shore A EVA at the distal half. There are ‘plugs’ under the right cuboid region, left 1st metatarsal-phalangeal joint and 1st tarso-metatarsal joint where the base material has been replaced with grey poron (Poron 4000, Algeos, Liverpool). 6mm grey poron is used as a top cover, giving a total 9mm base thickness (Figure 5).

Lateral heel wedging (3 degrees) was added to the existing foot orthoses, however the patient reported no immediate change. A further 5 degrees (8 degrees total) was added on the same day – the patient reported that the pain reduced to 1/10 immediately.


At review 8 weeks later, the patient reported that the pain had reduced to 0/10 24 hours following the addition of the lateral wedge. However, 72 hours after the addition of the lateral wedge the pain returned to 4/10. At this stage, the lateral heel wedge was increased to 12 degrees (Figure 6) and extended to the midfoot. The patient again reported an immediate reduction from 4/10 to 0/10.

To ensure that the aggressive wedging added was not causing high pressures in other areas of the foot, in-shoe pressure measurement was used. Comparisons were made with a 3mm poron inlay only, the custom foot orthosis only, and the custom foot orthosis with 12 degree wedge (Table 1). 

Sensor location Peak pressure (kPa) – 3mm poron inlay  Peak pressure (kPa) – custom foot orthosis Peak pressure (kPa) – custom foot orthosis with 12 degree lateral wedge
Lateral plantar heel 71 28 32
Medial plantar heel 69 18 8
Lateral plantar midfoot (Charcot deformity) 244* 94 133
Plantar 1st metatarsal-phalangeal joint 28 33 31

Table 1 Peak plantar pressures (*Indicates a peak pressure value exceeding the proposed dangerous level of 200kPa).

Considering 200kPa as a dangerous level of pressure [19], the custom FO reduced the lateral plantar midfoot (Charcot deformity) pressure to below this level. Following the addition of the lateral wedge, all plantar pressures tested remained below the 200kPa level. Some increase in pressure at the lateral midfoot was measured, reflecting the extension of the wedge to the midfoot. Slight increase in pressure was seen at the lateral heel, which seems to indicate that the centre of pressure was moved laterally by the lateral heel wedge.

At a second review appointment 6 weeks later, the pain had returned back to 4/10. The patient declined any other management and was happy to continue using the laterally wedged foot orthoses. At a third review 8 weeks later, the pain was slowly reducing and now rated as varying between 2/10 and 4/10.


This case study illustrates a relatively successful outcome in reducing pain associated with peroneal tendinopathy, using FOs only. The initial pain level of 7/10 was reduced by at least 3 points, which exceeds reported minimal clinically important difference (MCID) values [20]. Of interest is the fact that the patient reported marked immediate effects following the addition of lateral wedging to the existing FOs. This initial effectiveness tended to reduce over time, with pain levels increasing again. One possible explanation for this reduction in initial success may be some compression of the orthoses, which were not made with rigid plastic. The outcome may have been more successful if accompanied by other approaches such as physical therapy, however in this case due to patient preference only one approach was used.

Following initial use of a lateral wedge at the heel only, longer term reductions in pain were achieved by extending the wedge to the midfoot. The extension of the wedge to the midfoot has a logical anatomical basis, as the insertion of the peroneus brevis is distal to the heel, at the base of the 5th metatarsal. It is therefore logical to apply the opposing force in this area. The angle of the lateral wedge also needed to be increased to maintain pain reduction. A systematic effect of altering heel wedge geometry on external forces acting on the foot has been shown by Sweeney [21]⁠ although this relates to medially positioned wedging. The need for these small adjustments highlights the importance in this case not just of selecting an appropriate modification, but also the size and location of the modification. 

Applying relatively aggressive wedging to orthoses for feet at risk of ulceration may be controversial, as traditional approaches to designing FOs for high risk feet often focus on accommodation, rather than altering function of the foot. In this case, use of pressure measurement enabled verification that pressure levels were brought below 200kPa by the FOs, and that this reduction persisted despite the addition of a large lateral wedge. This indicates that aggressive FO designs may be safely used in high risk diabetic feet. However pressure measurement should ideally be used to assess the effectiveness and safety of any orthotic prescription in the context of a high risk foot.

The cause of the tendinopathy in this case is uncertain. The right foot and ankle may have become more prone to inversion as a result of changes to the bony architecture following CN. This may have in turn caused increased inversion moments at the rearfoot, and hence more stress on the peroneal tendons. Neuromuscular control may also be a factor, as the timing of muscle activation has been shown to be altered in diabetic patients [22]⁠⁠. 

This case report has illustrated that lateral wedging up to 12 degrees may be safe and not compromise the protective function of a FO in a high risk diabetic foot. Clinicians should consider peroneal tendinopathy as a possible cause of lateral ankle pain in neuropathic diabetic feet. Clinicians may consider orthosis wedging as one option to reduce pain in peroneal tendinopathy, in addition to other approaches.


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The vacuum phenomenon in the ankle joint: Air bubbles on CT

by Christopher R. Hood JR. DPM1*, Wesley A. Jackson DPM2, Robert C. Floros DPM3, David A. Bernstein, DPM4

The Foot and Ankle Online Journal 11 (2): 2

Gas or air bubbles in a joint space are most commonly associated with the “vacuum phenomenon,” a collection of gas that has precipitated out of solution to take up a gaseous state within a joint. This phenomenon was unbeknown to us upon a patient presentation, seen on computed tomography scan, and so further academic investigation was performed to define this pathology. Because of this lack of awareness, a PubMed® literature review was performed to analyze the rate of incidence in foot and ankle. Additionally, we present a case example of the vacuum phenomenon in the ankle joint of a 50-year old patient presenting with degenerative ankle joint pain symptoms. Further, a review of the condition as well as differentials is discussed in an attempt to raise awareness of this differential diagnosis for gas bubbles within a joint.

Keywords: Air bubbles, ankle, arthritis, CT, computed tomography, foot, gas bubbles, gaseous degeneration, vacuum phenomenon

ISSN 1941-6806
doi: 10.3827/faoj.2018.1102.0002

1 – Fellowship-Trained Foot and Ankle Surgeon, Premier Orthopaedics and Sports Medicine, Malvern PA.
2 – Resident, PGY-2, Bryn Mawr Hospital PMSR/RRA, Bryn Mawr PA.
3 – Private practice, Ocean County Foot & Ankle Surgical Associates, P.C., Toms River NJ and The Foot and Ankle Center, Haverford PA.
4 – Residency Director, Bryn Mawr Hospital PMSR/RRA, Bryn Mawr PA and Private Practice, Wayne PA.
* – Corresponding author: crhoodjr12@gmail.com

The presence of gas or air bubbles in a joint was first described by Fick in 1910 when he noticed gas bubbles in hand joints on radiograph (XR) evaluation while under traction [1-3]. Later this radiographic finding was coined the “vacuum phenomenon” (VP) by Magnusson in 1937 [2]. On imaging modalities such as computed tomography (CT) where it is most often visualized, it appears as a dark radiolucent pattern that can be shaped anywhere between a singular, linear bubble to confluence of bubbles within the confines of a joint space [2]. The shape is classically defined as a crescentic lucency paralleling a joint when found articular [3].

Gas bubbles were first thought to be associated with joint traction or trauma, but has since been found in situations of degenerative changes to joints [1,2]. Other associated gas bubble presenting pathologies include fracture-dislocation (e.g. traction injuries, open injuries introducing free air), ligament injury, metastasis, infection (e.g., abscess, osteomyelitis), cancer (e.g., multiple myeloma), intervertebral disc herniation/Schmorl’s nodes, abdominal or thoracic free air (e.g., digestive tract perforation, pneumothorax, air embolism), decompression sickness, and iatrogenic causes (e.g., surgical introduction of air, arthroscopy) [2,4].

Related to degenerative disease, its presence is most often cited to the sacroiliac (SI) joints (i.e., joint, facets, intervertebral discs) but also has been found in the pubic symphysis, lumbosacral space, and the joints of the temporomandibular, wrist, hand, hip, shoulder, knee, ankle (AKJ), subtalar (STJ), and calcaneocuboid (CCJ) [1-4]. Analysis of the gas in the SI location has found it to be predominantly nitrogen (> 90%) based , but oxygen and carbon dioxide among other gases are also present at much lower concentrations [2].

The purpose of this report was twofold: to determine the rate of occurrence of foot and/or ankle VP in the literature through a keyword search and present a case example of the VP to the AKJ in an end-stage degeneration clinical situation.


A PubMed® advanced keyword search was performed on May 1, 2017,  using the term combinations of “air bubble,” “bubble,” “gaseous degeneration,” “vacuum phenomenon,” with “foot” or “ankle.” The search had no restriction parameter fields applied. (Table 1) The returned abstracts were reviewed to determine their validity whether relevant to the primary search goal of obtaining articles demonstrating the VP from the ankle joint, distally. A table was then created counting the published instances of the VP in the foot and/or ankle.

Case Report

A 50-year old male patient presents to the senior author’s office after referral from a previous podiatrist due to his primary complaint of ankle pain. The patient described the pain as a progressive pain upon ambulation. The patient is very active and enjoys running and mountain climbing in particular. He states he can walk up to 8 miles until he can’t bare the pain anymore. He states his pain has been progressing in the ankle for 8 years now. Only rest has been able to alleviate his symptoms to this point in time. He has not sought any formal medical treatment prior to presentation.

Figure 1 50 year-old male, sagittal CT scan of the ankle. Note the gas formation in the joint as well as presence within the subchondral bone region. Associated talar dome arthritic changes. Images are left to right, lateral to medial.

Figure 2 50 year-old male, coronal CT scan of the ankle. Note the gas formation centered around, and within the cystic changes to the medial talar dome. Images are left to right, anterior to posterior.

Figure 3 50-year-old male, axial CT scan of the ankle. Note the gas formation is positioned with the lower-lying cartilage defect space. Images are left to right, superior to inferior slices.

Ankle Foot
  • “air bubble” / “ankle”
  • “air bubble” / “foot”
  • “bubble” / “ankle”
  • “bubble” / “foot”
  • “gaseous degeneration” / “ankle”
  • “gaseous degeneration” / “foot”
  • “vacuum phenomenon” / “ankle”
  • “vacuum phenomenon” / “foot”

Table 1 Key Word Search Parameters for Study Identification – Vacuum Phenomenon to the Foot and/or Ankle.

Ankle Foot
  • “air bubble” / “ankle” = 0
  • “air bubble” / “foot” = 1
  • None related to topic
  • “bubble” / “ankle” = 3
  • None related to topic
  • “bubble” / “foot” = 21
    • 1 discussing foot drop  developed 10 days post-op disc surgery, secondary to nerve root gas bubble (Kloc et al., 1998)(6)
    • 1 discussing STJ ROM using a bubble inclinometer
    • 1 discussing diabetic foot bullosis diabeticorum
  • “gaseous degeneration” / “ankle” = 0
  • “gaseous degeneration” / “foot” = 2
    • 1 discussing foot drop  developed 10 days post-op disc surgery, secondary to nerve root gas bubble (Kloc et al., 1998)(6)
  • “vacuum phenomenon” / “ankle” = 4
    • 1 related to dislocated joint/trauma of STJ and CCJ (Ahmad et al., 2007)(5)
    • 1 related to STJ and AKJ (Lee et al., 1994)(1)
    • 2 discussing lumbar pathology
  • “vacuum phenomenon” / “foot” = 2
    • 1 related to STJ and AKJ (Lee et al., 1994)(1)
    • 1 discussing foot drop  developed 10 days post-op disc surgery, secondary to nerve root gas bubble (Kloc et al., 1998)(6)

Table 2 Study Search Resulted Literature – Vacuum Phenomenon to the Foot and/or Ankle.

The patient’s past medical history consists of hemochromatosis. There is no known past surgical history to the foot or ankle. There is no known family history of foot or ankle pathologies at this time. Medications consist of hydrochlorothiazide and a baby aspirin daily.

The patient’s physical exam findings show limited dorsiflexion at the ankle joint and pain upon end range of motion in dorsiflexion at the ankle joint with a hard stop. His neurovascular status was grossly intact. There were no subjective complaints or objective findings of an infectious process based on the history and physical exam. He had no complaints of any other arthritic or painful joints. No other abnormalities were noted to his problem based exam.

A CT scan of the ankle exhibited degenerative joint disease to the talotibial joint along with a large anterior osteophyte of the distal tibia and talar neck at the ankle joint level. The CT scan also exhibited intra-articular gas centrally within the joint (Figures 1-3). Upon discussion with the reading radiologist it was declared that the gas was related to the VP. Further discussion with multiple facility radiologists where the study was performed revealed that the gas is due to nitrous oxide from surrounding synovial tissues, but can also be due to positioning of the ankle joint at the time of the study. From their experience, most VPs noted by these radiologists occur primarily in the lumbar spine and shoulders. None of them have seen such a finding in the ankle until this particular case.

Discussion of treatment options with the patient included less impacting exercises, an anterior ankle joint arthroplasty, and the need for a possible ankle joint replacement in the long term future. The patient was in favor of the anterior ankle arthroplasty procedure but would take time to think about his options moving forward. No treatments have been rendered to date and he has not returned to the senior authors’ facility.


From the PubMed® literature search, 33 articles resulted in total. After reviewing titles, abstracts, and database tags, removing irrelevant and duplicate entries, only two articles were relevant to this literature review of identifying examples of the VP in the foot and/or ankle (Table 2). This included a retrospective institutional review of CT imaging over two years evaluating the presence of gas bubbles in the lower extremity joints (i.e., AKJ, STJ, CCJ) and a case example of the VP in the STJ and CCJ after a trauma [1,5]. A third study found discussed a drop foot secondary to epidural gas formation and nerve root compression was not counted due to the distance location of the gas bubbles from the foot [6].


The VP is a combination of anatomy and physics, calling into play both Henry’s Law and Boyle’s Law through hydrodynamic cavitation [2,4]. Simply put, gas precipitates out of solution through a negative intra-articular pressure when a joint is distended (e.g. traction) or collapses. The newly created free space within the joint capsule needs to be filled, and is done so by gas (primarily nitrogen) [2,3]. In this situation it is often by a gaseous element that precipitates out of the local tissue or synovial fluid due to changes in pressure [1,2,4]. Gohil et al (2014) and Yanagawa et al (2016) provide detailed explanations of this phenomenon. Normally, this gas goes back into solution when the joint returns to its normal volume and pressure. However in situations of arthritis, a thickened or fibrotic/scarred joint capsule does not allow the gas to dissolve out. Furthermore, excess joint space due to the presence of cartilage loss and subchondral cysts allows the gas to remain out of solution to fill that “extra” space [1]. In situations of traction or trauma to a joint,  the blood gas nitrogen precipitates out of solution to fill the excess free intra-articular space from the joints’ distention [5]. In open fractures, the outside air fills the spaces within the extremity, and is not a true VP.

The presence of the VP may be seen as something no more than an academic finding when present on a CT scan of a lower extremity joint. It has been documented in instances related to trauma (i.e. sprain; joint dislocation; rapid joint distention,) degenerative disease, osteochondrosis, osteonecrosis, idiopathic, osteomyelitis / infection, or conditions specific to the joint found in [1,2,5]. Its finding is most often related to degenerative disease to a joint, easily seen on CT due to its greater sensitivity  with higher resolution compared to XR or magnetic resonance imaging (MRI) [1,2,4]. Associated pathology such as narrowed space, subchondral cyst, sclerosis, hypertropic degeneration to the joint may be seen along with the gas bubbles in degenerative situations across each imaging modality. In acute trauma, the presence of gas would suggest intact joint capsule and the associated intra-capsular ligaments however reports in the knee have shown otherwise [2].

When found, one important point is to correlate the finding to the presenting pathology through the patient history and physical exam so to not over or under diagnose the true pathology at hand [2,3]. This is most important when wanting to rule out any potential infectious processes such as septic joint, open fracture-dislocation, or penetrating joint trauma. Joint gas and spinal infection has been associated with bacteria such as obligate anaerobes or facultative organisms such as clostridia, Peptococcus, and E. coli [1,7]. Patterns of gas formation have been cited with different pathology from a linear formation in more benign pathology while bubble-like multi-lobulated patterns suggest infection [2]. In closed injuries, the presence may suggest a recent joint dislocation that otherwise may not be visible on imaging [5].

Specific to the lower extremity, Lee et al. (1994) performed an institutional retrospective review of CT scans over a two year period  to determine the incidence of gas within the STJ and/or AKJ [1]. It was documented in 12 cases (n = 495, 2.4%) on CT, none of which were related to infection. Of these, 11 were in situations of arthritis (post-traumatic, 10; non-traumatic, 1), 10 cases in the STJ, and although the XR did not show gas or air in the joints, degenerative changes were present and visible on both XR and CT. In the only other example, Ahmad et al. (2007) demonstrated the VP in a single case of an acute, closed STJ and CCJ fracture-dislocation [5]. One final unrelated  but interesting case included epidural gas collection secondary to vertebral disc degeneration causing nerve root compression and a drop foot [6]. Ultimately, surgical decompression resulted in resolution of the drop foot.

The VP is very under-reported in the literature and in radiology reports [2]. In the SI joint where the finding is most common, one study found only a 16% reported rate [2]. For the case presented here, the finding was not mentioned in the radiologists report. Only in calling the radiologist who performed the evaluation did we get an explanation of the gas finding seen on CT. The condition may be unfamiliar to physicians other than radiologist, as was in this instance, where more awareness would be important for the ordering physician to add the VP to their differential diagnosis of gas in a joint without jumping directly to infection [2,7].

The authors surmised the VP finding in the lower extremity may not be seen in high percentages due to two more reasons. These are based on the physics of the VP and some speculation [2]. The first is that the VP is most sensitive on CT imaging. In instances of acute trauma to the lower extremity such as traction injuries (i.e. sprains) that are often evaluated, diagnoses, and treated in the outpatient setting, an MRI is often the modality used if advanced imaging is required. In these traumatized joints, by the time imaging is performed, the gas has possibly gone back into solution and fluid fills any remaining excess intra-articular space. In acute injury settings such as joint dislocations, it has been suggests that gas bubbles may be routinely seen within 4 hours of dislocation while occasionally seen after 48 hours on CT scan [8]. Another multi-joint study found, after inducing a transient traction-VP, the gas bubbles to disappear within 10 minutes [3]. If acute fracture-dislocations present in the emergent setting and the more sensitive CT is ordered, the VP finding may often be overlooked due to the more pressing osseous trauma that requires urgent treatment or be attributed to a concomitant open injury and free air. Second relates to the duration of gas presence in a joint, other than the aforementioned points. In situations of chronic degenerative disease, over time the gas within the joint achieves a new solubility equilibrium and will dissolve back into solution and not be visible. The time to reach equilibrium was not found in any report.


The VP is a finding consisting of gas or air bubbles on CT within a joint space. Its finding is under represented in the lower extremity joints with only two citations to date (not including this report). The presence should not be alarming when seen in a non-infectious presentation. Although its finding to date is not correlated with a more advanced joint degeneration to the lower extremity, the finding can be another example of degeneration in addition to visible cartilage loss, subchondral cysts, and scarred joint capsules. This example adds to the literature base of VP to the lower extremity and provides another mode of bringing awareness to physicians who treat the lower extremity.

Financial Disclosures / Funding Declaration


Conflict of Interest





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  4. Yanagawa Y, Ohsaka H, Jitsuiki K, Yoshizawa T. Vacuum phenomenon. Emerg Radiol [Internet]. Emergency Radiology; 2016;23:377–82. Available from: http://dx.doi.org/10.1007/s10140-016-1401-6
  5. Ahmad R, Annamalai S, Radford M, Cook C. Vacuum phenomenon in a dislocated joint. Emerg Med J. 2007;24:862.
  6. Kloc W, Wasilewski W, Imieliński B, Karwacki Z. Epidural gas aggregation in the course of gaseous degeneration of lumbar intervertebral disk as a cause of foot paresis. Neurol Neurochir Pol. 1998;32(3):699–704.
  7. Nagashima T, Minota S. Air bubbles in the knee joint. J Clin Rheumatol. 2016;22(2):94–5.
  8. Fairbairn KJ, Mulligan ME, Indication A, Fairbairn KJ, Murphey MD, Resnik S. Gas bubbles in the hip joint on ct: an indication of recent dislocation. Am J Roentgenol. 1995;164(May):931–4.

Divergent Lisfranc injury with dislocation of great toe interphalangeal joint: A rare case report

by Dr. Ganesh Singh Dharmshaktu1*, Dr. Binit Singh2

The Foot and Ankle Online Journal 10 (3): 3

Injury to the Lisfranc joint is an uncommon event and requires keen evaluation to diagnose it early for the optimal outcome following adequate treatment. Many classifications describe the divergent pattern of this injury as separate entity and even rarer in incidence. The associated ipsilateral great toe interphalangeal dislocation along with the rare divergent pattern of Lisfranc fracture dislocation makes our case unusual. The case was managed by reduction of the great toe interphalangeal dislocation with percutaneous reduction and fixation of Lisfranc injury with screws and multiple K-wires, resulting in a good clinical outcome on follow up.  No single case similar to ours is reported previously to the best knowledge of the authors.

Keywords: foot, injury, dislocation, Lisfranc joint, tarsometatarsal joint, interphalangeal, management, fixation

ISSN 1941-6806
doi: 10.3827/faoj.2017.1003.0006

1 – Assistant Professor, Department of Orthopaedics, Government Medical College, Haldwani , Uttarakhand. India.
2 – Assistant Professor, Department of Orthopaedics, Government Medical College, Haldwani , Uttarakhand. India.
* – Corresponding author: drganeshortho@gmail.com

IInjury to the Lisfranc joint (Tarsometatarsal joint) is a rare event with reported incidence of 0.1 to 0.4% of fracture cases [1]. Early identification and meticulous management, often surgical, is required for optimal outcome as the conservative approach has been linked to poor results [2]. Quenu and Kuss did instrumental work to highlight the anatomical and clinical understanding of Lisfranc joint along with description of the “Lisfranc ligament bundle” bridging second metatarsal and first cuneiform bone as key stabilizing structure of tarsometatarsal (TMT) joint [3]. The classification given by the same authors is widely used and it describes three types of the injury; homolateral, isolated and divergent. Divergent dislocation was described as a complete disruption of the TMT joint with first ray and lesser rays displaced in the opposite direction. Another classification by Hardcastle et al modified the abovementioned classification on the basis of radiological evaluation into three types – complete, partial and divergent [4]. Type C or divergent variant was noted with medialisation of first metatarsal and lateral translation of variable number of rest of the metatarsals. The literature is scant about this rare pattern of injury as compared to other types.

Case Report

A 28-year-old male patient was brought to us with a history of injury to his right foot a few hours earlier. There was swelling and pain after the patient sustained an injury to the foot by the jumping off a moving bus. He reported he lost his balance and his foot was twisted before he fell to hard ground. The exact position of the foot at the time of impact is not properly recalled by the patient. There was visible deformity over medial aspect of foot and great toe suggesting presence of underlying significant bony or soft tissue injury. The radiograph of the affected foot showed fracture dislocation of Lisfranc joint along with inter-phalangeal dislocation of ipsilateral first toe. The pattern of Lisfranc injury was divergent with medial dislocation of first TMT joint and lateral dislocation of the rest of the TMT joint (Figure 1). There was also a fracture of the fifth metatarsal base with minimal displacement. Following informed consent, the patient was planned for urgent reduction of aforementioned injury with internal fixation. The rarity of the injury pattern was explained to the patient with additional written consent for future publication.

Figure 1 Preoperative radiograph showing great toe interphalangeal dislocation with divergent Lisfranc fracture dislocation.

The closed reduction of the interphalangeal dislocation was easily achieved under anesthesia which was later confirmed under fluoroscopy and the closed reduction of Lisfranc injury was achieved under fluoroscopic guidance. Two K-wires (2.0 mm) were introduced, one along the second metatarsal into the tarsal bones transfixing the Lisfranc joint. The other K-wire (1.0 mm) was introduced along the lateral TMT joints for added stability. The additional cortical screw (3.5 mm) was used for added stability from medial aspect and fixing the Lisfranc joint (Figure 2). The small wounds were dressed and a well-padded below knee plaster protection splint was applied following the confirmation of satisfactory alignment and fixation of the injuries. Elevation and non-weight bearing protocols were advised. Active toe and knee joint range of motion exercises were encouraged throughout the follow up. Gradual healing of the injury was noted in the follow-up along with reduction of swelling, pain and discomfort. The hardware were sequentially removed between 18-26 months postoperatively (Figure 3). The plaster splint was removed after eight weeks as swelling and pain were minimal. The only complication noted was hardware prominence of the medial screw that loosened over time and later was managed by its removal. The removal of K-wires and screw was uneventful at four and six month follow up. There was no re-dislocation of great toe noted and the patient was performing activities of daily living.

Figure 2 Postoperative radiograph showing the fixation of the Lisfranc injury with K-wire and screw from medial aspect along with reduced interphalangeal dislocation.

Figure 3 The follow up radiograph showing healed Lisfranc injury at the time of final hardware removal.


Meticulous clinical and radiological assessment is critical for the diagnosis of Lisfranc injuries as these are notoriously missed in emergency settings and may be the reason for later medico-legal issues [5]. The divergent dislocation, as in our case, have characteristic radiographic deformity that makes it hard to miss and the diagnosis is evident. The divergent Lisfranc fracture dislocation is stated to be associated with fractures of other bones in the foot like the cuneiforms and navicular [6].The subtle injuries, the doubtful diagnosis and the requirement of looking for interposed structure interfering with reduction calls for use of imaging like computerized tomogram (CT) or magnetic resonance imaging (MRI) [7,8]. Our patient refused further imaging due to financial issues and urgent operative intervention was initiated. Open reduction-internal fixation (ORIF) and primary arthrodesis are two common techniques. Our method with use of closed reduction and percutaneous fixation with wires and screws resulted in primary arthrodesis of Lisfranc joint. The reported incidence of secondary procedures for complications has been found to be minimal with primary arthrodesis [9]. Studies have also shown good outcome of primary arthrodesis in comparison with ORIF in the long term [9,10]. Primary arthrodesis also obviates need for secondary arthrodesis in case of arthritis following either modality of treatment. Our minimal invasive approach resulted in early discharge and avoided wound complications.

Acknowledgement None


  1. Court-Brown CM, Caesar B. Epidemiology of adult fractures. A review. Injury, 2006;37(8):691-697. PubMed  
  2. Myerson MS, Fisher RT, Burgess AR, et al. Fracture dislocations of the tarsometatarsal joints: End results correlated with pathology and treatment. Foot Ankle.1986;6(5):225-242. PubMed
  3. Quenu E, Kuss G. Etude sur les subluxations du metatarse (luxations metatarsotarsiennes) du diastasis entre le 1stet le 2nd metatarsien. Rev Chir(Paris).1909; 39:281-336,720-791,1093-1134.
  4. Hardcastle PH, Reschauer R, Kutscha-Lissberg E, et al. Injuries to the tarsometatarsal joint. Incidence, classification and treatment. J Bone Joint Surg Br.1982;64(3):349-346. PubMed
  5. Chesbrough RM. Strategic approach fends off charges of malpractice: Program provides tips for avoiding litigation. Diagn Imaging 2002;24(13):44-51.
  6. Berquist TH, editor. Trauma. Radiology of the Foot and Ankle. New York: Raven Press, 1989. p. 191-7.
  7. Philbin T, Rosenburg G, Sferra JJ. Complications of missed or untreated Lisfranc injuries. Foot Ankle Clin North Am 2003;8:61-71. PubMed
  8. Kiuru MJ, Niva M, Reponen A, Pihlajamaki HK. Bone stress injuries in asymptomatic elite recruits: a clinical and magnetic resonance imaging study. Am J Sports Med. Feb 2005;33(2):272-276.
  9. Henning JA, Jones CB, Sietsema DL, et al. Open reduction internal fixation versus primary arthrodesis for lisfranc injuries: A prospective randomized study. Foot Ankle Int. 2009;30(10):913-922. PubMed
  10. Ly TV, Coetzee JC. Treatment of primarily ligamentous Lisfranc joint injuries: primary arthrodesis compared with open reduction and internal fixation. A prospective randomized study. J Bone Joint Surg Am.2006;88(3):514-520. PubMed

Atraumatic acute compartment syndrome secondary to group C Streptococcus infection

by Amelia Aaronson1*, Malcolm Podmore1, Richard Cove1pdflrg

The Foot and Ankle Online Journal 9 (4): 4

A 74 year-old female presented to the emergency department with sudden onset severe foot pain and was diagnosed with an acute, atraumatic compartment syndrome. The patient had urgent surgical decompression and washouts in theatre. Microbiological samples grew group C hemolytic Streptococcus; she was treated with high dose intravenous antibiotics and made a good recovery.

Keywords: atraumatic compartment syndrome, foot, group C hemolytic Streptococcus

ISSN 1941-6806
doi: 10.3827/faoj.2016.0904.0004

1 – North Devon District Hospital, Raleigh Park, Barnstaple EX31 4JB
* – Corresponding author: amelia.aaronson@nhs.net

This case is important for two reasons; Firstly, because regardless of cause, compartment syndrome is a surgical emergency and is a diagnosis which requires early recognition and appropriate treatment. Secondly and most important, because it is an unusual presentation and pathophysiology of compartment syndrome. Cases of atraumatic compartment syndrome have been reported previously [1], with causes including reperfusion injuries, bleeding, animal toxins, and intravenous drug use [2], and have been reported in the literature [1], but the majority of acute cases are due to trauma. When searching the literature for infectious causes, there are even fewer cases [3,4], and no cases have been previously described due a group C Streptococcus infection.

Case Presentation

A 74 year-old female presented to A&E with a five-hour history of acute left foot pain, which had increased in severity to a subjective 10/10 and required intravenous morphine and nitrous oxide. The patient described pain all over her left foot, especially the big toe and dorsum of the foot. There was no history of trauma, the patient was systemically well, and had no other notable symptoms.

Past medical history included hypertension, atrial fibrillation, and a previous laparoscopic cholecystectomy. The patient had no known drug allergies, and her only medication was 5 mg Ramipril QD. The only relevant family history was gout.

On examination the patient’s foot was swollen throughout the dorsal and plantar aspect, slightly warm to touch, and extremely tender to palpation. There was acute pain with all passive movements of the foot and toes, and ankle movements were restricted due to pain. The foot exhibited no neurovascular compromise and had no lacerations or wounds. She was afebrile, and observations were all normal.


On admission white cell count was 13.5/mL and C-reactive protein 10 mg/L. Other blood values (including uric acid and creatine phosphokinase) were normal.

Left foot radiographs revealed no acute abnormalities, and an MRI showed a large amount of high signal over the dorsum of the foot. However, only one long axis STIR sagittal acquisition was obtained due to patient discomfort and difficulty remaining still.

The patient was referred to the trauma and orthopedics team due to severe pain out of proportion to the history, where the differential diagnosis included infection and compartment syndrome.


Despite an inconclusive MRI, due to a high clinical suspicion of compartment syndrome the patient went to surgery the same day for a fasciotomy of her left foot. Due to dorsal swelling and the MRI result, the four interosseous compartments were decompressed through two dorsal incisions. The compartments deep to these were decompressed through the same incisions. The muscles appeared viable, there was no collection, and a small amount of fluid was found in the lateral deep compartment. This fluid was sent for microbiological analysis, and the wound was left open with a vacuum dressing and the leg kept elevated post-operatively.

Outcome and Follow-Up

The patient’s pain was much improved postoperatively; nerve blocks were not performed. Two days later the patient’s pain increased, this time more focussed on the medial foot. She was taken back to surgery for a medial fasciotomy to release the medial compartment. The muscles were viable, with no suggestion of infection.

Despite this, the patient began to spike temperatures and had high inflammatory markers. CRP peaked on day 5 at 474 mg/L, although white cell count did not rise higher than the admission level. Cultures of fluid from both fasciotomies grew group C hemolytic Streptococcus. It was therefore thought that this patient’s compartment syndrome was secondary to infection – although there was no history of any wound or animal bite, and on examination no entry site for infection had been found. She was treated with intravenous amoxicillin, initially 1g TID, which was later increased to 2g QID on day ten of admission.

Three days later she had a planned third surgery. The medial wound was clean and therefore closed, but the two dorsal wounds were irrigated with saline and left open. Four days after this the patient had a planned fourth surgery with the medial wound healing, and the dorsal wounds had no pus although the dorsum was still very swollen. The wounds were washed out and left to heal by secondary intention.

A repeat MRI was performed on day twelve because of persistently high inflammatory markers, which showed no evidence of soft tissue or intraosseous collection. She continued high dose intravenous antibiotics, and started to recover. CRP tailed off following this, and her pain settled. The patient was discharged after a twenty-five day admission with outpatient follow up.


Compartment syndrome is caused by an increase of pressure in a closed compartment bounded by fascia and bone  compromising vascular supply to that compartment. It is usually due to bleeding or edema secondary to trauma or reperfusion injury [5,6] and can be acute or chronic. The majority of acute cases are secondary to trauma [7] including fractures, crush injuries and surgery [8]. A study looking at causation showed that the most common cause in over two-thirds of patients was fracture, followed by soft tissue injury and then bleeding disorder or use of oral anticoagulants [9]. Other causes include tight casts, burn injuries, and vascular injuries. The treatment of choice for acute compartment syndrome is immediate decompression by fasciotomy [5].

A diagnosis of compartment syndrome is suggested by history and examination; pain is thought to be the first and most sensitive sign [10], although other symptoms include paraesthesia, limb paresis, lack of pulses, and pallor [11]. However, when the diagnosis is in doubt other investigations include measuring tissue pressure and nerve stimulation [12]. Compartment pressures within 30-mmHg of diastolic pressure would suggest compartment syndrome [11]. There should be a low threshold for surgical intervention and clinical symptoms alone are usually enough to justify surgery.

Acute compartment syndrome most commonly involves the lower limb and cases involving the foot have been reported previously [13]. There is no consensus on the number of compartments in the foot, but it is most commonly argued that there are nine compartments in the foot – four interosseous compartments, three central (superficial, central and deep), the medial compartment and the lateral compartment [8, 14, 15]. Effective decompression can be achieved from dorsal incisions, as was done in this case because of the dorsal swelling and MRI findings; however a single medial incision can be used to decompress all nine foot compartments [15].

There has been debate amongst foot and ankle orthopaedic surgeons as well as military surgeons about surgical decompression versus conservative treatment for compartment syndrome of the foot. A recent survey of military surgeons concluded that if compartment syndrome is suspected, it should be decompressed with the aim of preventing chronic pain and deformity [16].

Atraumatic compartment syndrome of the foot is a rare condition; case reports of compartment syndrome secondary to infection have been described, but no cases due to group C hemolytic Streptococcus. One paper describes three case reports of acute, atraumatic compartment syndrome in the lower limb, one seemingly spontaneous, and two secondary to gastrocnemius hematomas and subsequent edema [1]. A small number of case reports have described similar cases of compartment syndrome of the upper limb secondary to infection (group A hemolytic Streptococcus) requiring decompression and antibiotics and, in one case, amputation [3,4].

Group C Streptococcus (and group G Streptococcus) of human origin are thought to be a single subspecies, Streptococcus dysgalactiae subspecies equisimilis. They are a normal commensal flora of the upper respiratory tract, skin, gastrointestinal tract, and female genital tract, and have been identified in pharyngitis, septic arthritis and osteomyelitis, soft tissue infections and meningitis [17].

Atraumatic cases can be easily missed, risking complications such as contractures or deformities of the foot, weakness, paralysis, sensory neuropathies and rarely amputation [8]. There is high morbidity and mortality [2], and it is now thought that serious complications such as muscle necrosis can occur as early as within three hours [18]. The risk of long-term complications is reduced the earlier a compartment syndrome is decompressed, although as acute compartment syndrome is relatively uncommon, there are no large studies describing chronic sequelae and overall patient outcomes [11].

There are several learning points from this case report, primarily that acute foot compartment syndrome is a limb threatening emergency which needs rapid recognition and often surgical decompression. Although the majority of acute cases are secondary to trauma, it is important to remember that there can be atraumatic causes as these are more likely to be missed. If a diagnosis is in doubt from the clinical history and examination, there are other investigations – such as measurement of compartmental pressures, but it is important not to delay fasciotomy due to associated morbidity and mortality of untreated acute compartment syndrome.


  1. Cara JA, Narvaez A, Bertrand ML, Guerdo E. Acute atraumatic compartment syndrome in the leg. Int Orthop. 1999; 23(1): 61 – 62
  2. Stracciolini A, Hammerberg EM. Acute compartment syndrome of the extremities. http://www.uptodate.com/contents/acute-compartment-syndrome-of-the-extremities (accessed 16 June 2016).
  3. Taylor J, Wojcik A. Upper limb compartment syndrome secondary to Streptococcus pyogenes (group A Streptococcus) infection. J Surg Case Rep. 2011; 3: 3
  4. Schnall SB, Holtom PD, Silva E. Compartment syndrome associated with infection of the upper extremity. Clin Orthop Relat Res. 1994 (306): 128–31 
  5. Matsen FA, III. Compartmental syndrome. An unified concept. Clin Orthop Relat Res. 1975;(113):8-14.
  6. Heemskerk J, Kitslaar P. Acute compartment syndrome of the lower leg: retrospective study on prevalence, technique, and outcome of fasciotomies. World J Surg. 2003; 27(6):744 – 747
  7. Bonutti PM, Bell GR. Compartment syndrome of the foot. A case report. J Bone Joint Surg Am. 1986; 68 (9): 1449 – 1451
  8. Fulkerson E, Razi A, Tejwani N. Review: acute compartment syndrome of the foot. Foot Ankle Int. 2003; 24(2): 180 – 187
  9. McQueen MM, Gaston P, Court-Brown CM. Acute compartment syndrome – Who is at risk? J Bone Joint Surg Br. 2000; 82(2): 200-3
  10. Ulmer T. The clinical diagnosis of compartment syndrome of the lower leg: are clinical findings predictive of the disorder? J Orthop Trauma. 2002; 16: 572 – 577
  11. Frink M, Hildebrand F, Krettek C, Brand J, Hankemeier S. Compartment syndrome of the lower leg and foot. Clin Ortho Relat Res. 2010; 468(4): 940 – 950
  12. Matsen FA IIIWinquist RAKrugmire RB Jr. Diagnosis and management of compartmental syndromes. J Bone Joint Surg Am. 1980; 62(2):286-91.
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  16. Middleton S, Clasper J. Compartment syndrome of the foot – implications for military surgeons. J R Army Med Corps. 2010; 156(4): 241-4
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  18. Vaillancourt C, Shrier I, Vandal A, Falk M, Rossignol M, Vernec A, Somogyi D. Acute compartment syndrome: How long before muscle necrosis occurs? CJEM. 2004; 6: 147 – 154

Application of the distally pedicled peroneus brevis: Technique, case study, and pearls

by Chad Seidenstricker DPM1, Megan L. Wilder DPM2, Byron L. Hutchinson DPM, FACFAS3pdflrg

Soft tissue defects of the distal leg and hindfoot are difficult to eradicate. Avascular structures become exposed through seemingly superficial wounds rather quickly. The present case describes a surgical technique for the peroneus brevis muscle flap for coverage of a postoperative lateral heel wound following a lateral extensile approach for ORIF of a calcaneal fracture. Nonoperative and operative wound care modalities failed over the course of several years, and a peroneus brevis rotational flap was attempted for wound coverage. Although several minor complications occurred, the wound had successful epithelialization at 3 months. The distally pedicled peroneus brevis muscle flap offers a good option at wound coverage in difficult to heal wounds of the distal leg and hindfoot.  

Key words: muscle flap, peroneus brevis, soft tissue defect, ankle, foot

ISSN 1941-6806
doi: 10.3827/faoj.2016.0903.0003

1 – Podiatry Resident at Swedish Medical Center PGY-3, Seattle, WA
2 – The Everett Clinic, Marysville, WA
3 – Director, Franciscan Foot and Ankle Institute; Medical Director, Foot & Ankle Service, CHI Franciscan Health, Federal Way, WA.
* – Corresponding author: chaddpm14@gmail.com

Soft tissue defects of the foot and ankle present a significant challenge. There is little soft tissue coverage and exposed tendon and bone can easily occur following elective reconstruction or trauma, requiring surgery. Skin grafting is often not an option in this region as bone and tendon are not suitable as a recipient bed. Rotational muscle flap techniques for foot and ankle wound closure are gaining popularity and have proven effective. Muscle flaps offer pliability and can eradicate dead space, can overcome residual bacterial infection in bone, improve blood flow, and will provide a vascular recipient bed for split thickness skin grafting [1]. While negative pressure wound therapy devices are excellent at promoting expedited closure of deep wounds, they should not be placed directly over bone or tendon and especially not in the setting of residual infected tissue.

Indications for rotational muscle flap wound closure may include exposed bone with osteomyelitis, traumatic wounds, non-healing wounds over the lateral ankle and hindfoot after Achilles tendon procedures, surgical wound dehiscence recalcitrant to nonoperative therapies after calcaneal fractures, ankle fractures, and total ankle arthroplasty. In a systematic review, Yu et al, demonstrated a wound complication rate of 13.5% in calcaneal fractures after ORIF [2]. There has been a movement toward minimally invasive techniques, but the lateral extensile incision is still routinely utilized. Raikin et al demonstrated an 8.5% incidence of wound complications following TAR with anterior midline incisional approach that required at least one secondary visit for surgical wound debridement [3]. Wound dehiscence after TAR requires immediate definitive treatment to avoid catastrophic deep space infection.

The distally pedicled peroneus brevis muscle flap offers a relatively simple, reproducible and reliable option for wound closure with complication rate equal or reduced compared to other techniques. In general the muscle flap should not be used as a first line procedure, but is used in limb salvage situations and has very little downside. The peroneus brevis muscle flap also has the advantage of low donor site morbidity and heals with minimal scar.  Lower extremity surgeons can easily perform the peroneus brevis flap closure if it is acceptable in the foot and ankle specialist’s region to perform this type of procedure.

Rationale & Background

Attinger described the role of various intrinsic muscle flaps for small wound closure of the foot and reported a 96% success rate [4]. The abductor hallucis muscle flap has been reported to provide excellent outcomes in plantar heel defects [4,5]. While intrinsic flaps have proven efficacy for small wounds about the foot, they are not sufficient for larger wounds of the hindfoot, ankle and lower leg. Larger wounds in the distal third of the leg and hindfoot are amenable to the peroneus brevis flap. The peroneus brevis muscle is classified as a type IV muscle flap by Mathes and Nahai, which represents a muscle flap with segmental blood supply provided by branches of equal importance (Table 1) [6]. Ensat et al evaluated the blood supply of the peroneus brevis muscle flap identifying constant blood supply by segmental branches of the peroneal and tibial arteries and also supported Yang’s finding of the most distal pedicle being provided between 4-5 centimeters proximal to the tip of the fibula [7,8]. Ensat also recommended a pivot point at least 6-cm above the tip of the fibula to assure there is an intact vascular pedicle, however, this should always be evaluated intraoperatively [7]. The muscle length available for rotation is close to 20-cm, but due to distal flap necrosis, the most proximal 2-cm should always be removed, providing a muscle approximately 18-cm in length [9,10,11].


Table 1: Mathes & Nahai [6] classification of muscle and myocutaneous flaps
Type I: One vascular pedicle
Type II: Dominant pedicle(s) and minor pedicle(s)
Type III: Two dominant pedicles
Type IV: Segmental vascular pedicles (ie Peroneus Brevis)
Type V: One dominant pedicle and secondary segmental pedicles

The arc of rotation is determined by the most distal vascular pedicle, which should allow an average of 12-cm from the pivot point.

We present a case in which a chronic lateral heel wound following ORIF of calcaneus was treated successfully with a distally pedicled peroneus brevis flap. Our scenario is similar to Rodriguez who recently reported success of the peroneus brevis flap following wound dehiscence after ORIF of a lateral malleolar fracture with subsequent surgical wound dehiscence [12].

Case report

In this case report, a 63 year old male non-smoker sustained a closed intra-articular calcaneal fracture. The records from previous surgeons were not retrieved so the exact timeline is unknown but the following events occurred over the course of several years prior to his definitive operation and closure. The patient had an ORIF through a lateral extensile approach with dehiscence at the apex of the incision which never fully healed.  He had hardware removal and local wound care which failed. He then had a small rotational flap which failed, followed by an advancement flap which resulted in re-opening of the sinus tract and a chronically draining wound with exposed bone. He presented to a local plastic surgeon for consultation who felt a free flap was not a good option. He then presented to the author’s clinic for a preoperative evaluation.  On arrival to clinic the patient had a small wound at the apex with a sinus tract and suspected osteomyelitis of the lateral calcaneal wall, which was draining minor amounts of serous fluid (Figure 1). A distally pedicled peroneus brevis rotational flap was planned.


Figure 1 Chronic lateral hindfoot wound recalcitrant to several operative debridements, antibiotics, local wound care, and local skin flaps.


Figure 2 Lateral incision over the fibula, with the peroneus longus retracted inferiorly and the peroneus brevis muscle belly and tendon origin exposed.

Surgical technique

After skin preparation, and exsanguination of the limb, a pneumatic thigh tourniquet was inflated to 350mmHg. An incision was made overlying the lateral heel wound in a curvilinear fashion extending a few centimeters proximally and a few distal to the wound. The scar tissue was bluntly dissected through down to calcaneus, and the skin was elevated in a single layer as a flap. There was a loose portion of cement that was noted in the lateral wall of the calcaneus which had been left from a prior surgery and this was removed.


Figure 3 Peroneus longus in the right hand, and peroneus brevis muscle belly held in the left.


Figure 4 Peroneus brevis muscle belly being elevated off the fibula, moving proximally.

The calcaneus was debrided to good, healthy bleeding bone that appeared without signs of infection. Attention was then directed to the lateral leg where a standard incision was made as described by Eren [13]. The incision connected with the lateral heel wound incision. The crural fascia overlying the peroneals was incised (Figure 2). The peroneus brevis was followed up its muscle belly proximally until the origin was released (Figure 3,4,5). Segmental pedicles were ligated from proximal to distal until approximately 6-cm proximal to the lateral malleolus.


Figure 5 The free peroneus brevis flap, with distal vascular pedicles still in tact.


Figure 6 Intraoperative doppler to assure the pedicle is patent to provide blood supply to the brevis muscle.


Figure 7 The peroneus brevis muscle flap rotated down, showing adequate length to reach the lateral heel wound.


Figure 8 Closure of the harvest site, demonstrating easy closure of the harvest site.

Utilizing ultrasound, a vascular pedicle was identified at this level (Figure 6). Care was taken to not violate the pedicle. The peroneus brevis was folded from proximal to distal into the wound and overlying the exposed calcaneal wound (Figure 7). It was loosely secured in place overlying the lateral wall of the calcaneus. The wound was then closed in layers proximally, leaving the distal wound overlying the lateral wall of the calcaneus open with the muscle flap secured within the wound (Figures 8,9).

An Integra bilayer wound matrix was then placed and trimmed to the appropriate size overlying the muscle flap (Figure 10). It was secured in place around the rim of the wound utilizing staples with a single staple in the middle of the flap. The membrane was then fenestrated to allow drainage. The site was then dressed with negative pressure wound therapy (Figure 11). A monorail external fixator was applied to the medial calcaneus and medial tibia with half pins to establish stability while being able to access the wound for local wound assessment and care in the early wound healing phase (Figure 12). Proper alignment was confirmed under fluoroscopy. Sterile dressings were then applied. Tourniquet was deflated.


Figure 9 Closure of the incision along the lateral leg down to the original defect site. The original defect site should be left open, and ideally is covered with a biologic dressing.


Figure 10 Securing an Integra graft over the exposed peroneus brevis in the chronic wound site with staples.


Figure 11 Wound vac secured over the Integra graft after fenestrating the integra graft.


Figure 12 Unilateral External fixator applied to the medial tibia for stabilization of the muscle and the wound to allow for incorporation.


Figure 13 Application of STSG roughly 3 weeks after the Integra graft was placed. The silicone layer was removed and the wound was carefully debrided and cleansed prior to application. STSG secured with staples.


Figure 14 Healed lateral foot wound.

Follow up care

About 2 weeks later, he presented to the emergency department with fever and chills and was noted to have a pin tract infection, requiring removal of one of the pins in the ED. The following week he returned to the operating room for removal of the external fixator and debridement of a small portion of muscle flap necrosis.  Following debridement, the split-thickness skin graft (STSG) was secured with staples and negative pressure wound therapy was applied (Figure 13). The patient presented to clinic for follow-up seven days post-skin graft application and negative pressure wound therapy was removed. Four days later he returned to clinic and reported a visit to the ED for fever and previous talar pin site irritation and pain with two centimeter diameter of surrounding erythema. He was started on IV rocephin for a few days and then transitioned to a two week course of Keflex. He had resolution of infection. His donor site incision healed without incident. He was discharged with instructions to remain NWB to his surgical limb until complete incorporation of graft, about two months. At final three-month follow-up he had completely healed (Figure 14).


There are several key points to discuss regarding this case report. First, there was partial flap necrosis, which required repeat debridement in the OR. For the case presented, the most proximal aspect of the peroneus brevis muscle belly was not debrided, which has been recommended by multiple authors [9,10,11]. Other potential ways to improve wound closure may include the use of bilayer membrane which, after it takes, will provide a superior surface for a STSG. Negative pressure wound therapy can be applied at 50-125mmHg [12]. It has been proposed that higher vacuum settings may be damaging to skin grafts, but this theory was not upheld [13].

Recently it was found that wound vac application at 75mmHg applied for seven days post-operatively significantly reduced partial flap necrosis and skin graft necrosis, and they concluded that prolonging the period of wound vac application may further reduce complications by eliminating shear force, improving neovascularization of the muscle, and reducing edema and venous congestion [14]. There is debate whether to perform the transfer of the brevis through a subcutaneous tunnel or whether to connect the harvesting incision to recipient site. It is not absolutely necessary to connect the incision with the recipient site, but there should not be excessive tension within the subcutaneous tunnel as this may obstruct venous outflow resulting in flap failure. If there is question, one should connect the recipient bed with the donor site incision.  

A few other obstacles occurred which can be avoided. While pin tract infections are common when using external fixators, rarely catastrophic infection develops. Minor infections can be managed with local wound care and oral antibiotics oftentimes. As long as there is not failure at the bone-pin interface with loosening, fracture with nonunion or malunion, or chronic osteomyelitis,  it should not compromise your end result. Placing a unilateral fixator to stabilize the extremity offers several advantages. It offers stability to the extremity and the wound bed in the immediate postoperative phase while also permitting wound care and wound observation for the first few weeks after index surgery. The external fixator can be removed at the three week mark as this is when you can return to the operating room, remove the silicone layer from the bilayer membrane, and harvest and apply the STSG. Other options include applying a posterior splint for immobilization, but this doesn’t offer an easily accessible portal for wound evaluation and wound care and, makes continued care with a wound vac particularly difficult. If the recipient site is prone to shear forces, ie lateral malleolus, be sure to utilize a bulky soft dressing to protect the graft site. Although several publications [14,15] have advocated for single stage procedure, it is prudent to wait for application of the STSG until muscle flap viability is assured. This prevents unnecessary repeat skin grafting.

It has been demonstrated that the peroneus brevis muscle flap provides a reliable means for treating bone infections, providing blood supply, and a suitable recipient bed for skin grafting [1]. Preoperatively the patients should be evaluated for vascular insufficiency. As foot and ankle experts, sacrificing the primary evertor of the foot may seem uncouth, but these are limb salvage situations. One can perform a tenodesis of the the peroneus brevis to the longus to enhance eversion power if it is possible. However, it has been shown that eversion and plantarflexion are maintained following the procedure even without ancillary procedures and patients do not report lateral ankle instability [16]. The donor site is rarely problematic, and can be closed primarily without issue [10-12,16-18].

The peroneus brevis has a consistent blood flow [7,16,17]. The maximum number of vascular pedicles should be maintained as possible, but one can elect to ligate all pedicles leaving only the most distal intact approximately 6-cm proximal to the tip of the fibula. To ensure adequate blood supply will be provided by each successive pedicle, a vascular clip can be placed temporarily to ensure the next pedicle maintains adequate perfusion. Ensat et al demonstrated in a cadaveric model that there were an average of 5.1 segmental branches to the muscle. This included branches from both the peroneal and the anterior tibial artery, however, most branches were derived from the peroneal artery [7]. The most distal vascular branch was derived from the peroneal artery in 100% of cadavers at a distance about 4.3cm proximal to the tip of the lateral malleolus. There is also retrograde flow provided from the posterior tibial artery [7]. This is important in gaining a muscle flap with the most potential length. The pivot point should be at least 6-cm proximal to the lateral malleolus to ensure there is a vascular pedicle attached distally to supply the muscle when performing rotational flaps. The diameter of the pedicle must be at least 0.5mm, while the average size pedicle is 1.1mm this is rarely a problem [7]. The average length of the muscle is 19.8cm, but the most proximal 2-cm should be resected as this area of the graft is expected to undergo necrosis.

In conclusion, many studies have found reliability in this muscle flap. It offers great utility to cover defects in the distal leg and hindfoot. It can cover defects of the anterior ankle, lateral ankle and hindfoot. Despite some authors reporting an unfavorable success rate, the majority of reports found high rates of success and this should be considered in the reconstructive ladder for complex lower extremity wounds [10,11,18,19].


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  5. Ortak T, Ozdemir R, Ulusoy MG, Tiftikcioglu YO, Karaaslan O, Kocer U, Sensoz O. Reconstruction of heel defects with a proximally based abductor halluces muscle flap. J Foot Ankle Surg 2005; 44(4): 265-270.  PubMed
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Giant conventional schwannoma of the foot: A case report

by Low Chin Aun, MBBS; Agus Iwan Foead, MS Orthpdflrg

The Foot and Ankle Online Journal 7 (4): 3

Schwannomas, also known as neurilemmoma, are amongst the most common tumors arising from peripheral nerves. It usually presents as a solitary swelling and may occur anywhere in the body with a neural supply. However, its occurrence in the foot is rarely reported. We report a case of a sixty year old man with a large schwannoma of his right foot, who never sought treatment for 20 years since its first occurrence.

Key words: Schwannoma, neurilemmona, tumor, foot

ISSN 1941-6806
doi: 10.3827/faoj.2014.0704.0003

Address correspondence to: Low Chin Aun
Department of Orthopaedic Surgery, Hospital Tuanku Ampuan Najihah, Kuala Pilah, Malaysia.

Schwannoma is the most common benign, neurogenic tumor arising from Schwann cells of nerve sheaths. It occurs most frequently in the head and neck region, especially involving cranial nerves and brachial plexus. It is seldom reported in the upper and lower limbs [1]. This tumor grows in variable size and usually present as a slow growing solitary tumor, rarely associated with pain and paraesthesia. Neurological symptoms often accompany larger swelling. Its occurrence in the foot is rarely reported. Schwannomas constituted 5% of all benign soft-tissue tumors, and only 9% of these schwannomas were found in the foot or ankle [2]. We report a case of a large cutaneous schwannoma of the foot and its management.

Case Report

A 60-year-old man presented to our orthopaedic outpatient clinic with complaints of a solitary swelling over the lateral aspect of his right forefoot. He claimed the swelling has been gradually increasing in size for the past twenty years and was associated with intermittent pain and paraesthesia at his right foot. The swelling prohibited him from wearing his footwear due to its size. Patient has tried traditional treatment with massage and ointments but had no improvement. His past medical history was unremarkable and there was no family history suggestive of neurofibromatosis.

Physical examination revealed a 10cm x 10cm x 8cm tumor over the lateral aspect of his right foot (Figure 1). Its consistency was firm, and it was attached to the underlying tissue. On percussion, it produces an electric shock similar to Tinel’s sign. However, there was no tenderness, erythematous, warmth or ulceration of the skin over the tumor. Neurovascular status of the right foot was normal. Systemic review was unremarkable. Plain radiograph of the right foot did not show any bony involvement (Figure 2).


Figure 1 Swelling on the lateral aspect of patient’s foot.


Figure 2 X-rays revealing a tumor on the lateral aspect of patient’s right foot.

At surgical excision, the capsule was found at the deeper plane. There was no attachment of the tumor with adjacent soft tissue which permitted easy in toto removal. The wound was then closed with split skin graft harvested from his left thigh. The patient did not experience any complication postoperatively. The tumor was preserved in formalin solution and sent to the pathology lab. One month later he was reviewed again in the clinic. There were no evidence of recurrence and his wound had healed well with good uptake of the skin graft (Figure 3). Histopathological examination revealed a conventional right foot schwannoma with cystic degeneration.


Figure 3 Well healed wound post-removal of schwannoma.


Schwannoma of the foot is interesting due to its rarity. Its diagnosis and treatment should be differentiated with neurofibroma or malignant peripheral nerve sheath tumor (MPNST). Schwannoma is embryologically derived from neuroectodermal Schwann cell which forms the myelin sheath that facilitates transmission of nerve impulses [3]. This well encapsulated tumor is usually benign in nature and malignant transformation is rarely reported [4]. Multiple schwannomas have been reported to have autosomal dominant inheritance. These tumors have also been associated with von Recklinghausen’s disease in which there is somatic mutation of NF2 gene. It appears that it has no geographical and race predilection. The average age of its presentation is 20 – 50 years with a mean age of 46 [2].

Benign peripheral nerve sheath tumors are divided into two major groups; Schwannoma and neurofibroma. Differentiation of schwannoma from neurofibroma is of importance because schwannoma can easily be shelled out without injuring the nerve contiguity. In neurofibroma, the nerve is incorporated into the mass. Surgery of neurofibroma might need to resect the nerve, and subsequent nerve grafting might be needed to restore function. Large schwannoma commonly undergo cystic degeneration. Few neurofibromas have cystic changes due to myxoid degeneration. There has been argument about the cystic degeneration between the two tumors. Most literature showed schwannoma has higher chance of cystic degeneration compared to neurofibroma. Histogenesis of schwannoma and neurofibroma has been argued for decades and is beyond the scope of the discussion. It suffices to say that solitary schwannoma is composed almost exclusively of cells with characteristics of differentiated Schwann cells. However neurofibroma shows the presence of three types of cells, i.e. Schwann-like cells, perineurial-like cells, and fibroblast-like cells. Histologically staining with S-100 shows that schwannoma has hypercellular area alternating with hypocellular area, which respectively are called Antoni A, and Antoni B areas. The hypercellular area is made up of spindle cells with tapered nuclei arranged in palisading pattern whereas the hypocellular area is composed of loose stroma [4].

Malignant peripheral nerve sheath tumor (MPNST) is a sarcoma which can originate from peripheral nerve or from the cell associated with the nerve sheath, such as Schwann cell, perineural cell, or fibroblast [5]. The term MPNST replaces previously used names including malignant schwannoma, neurofibrosarcoma and neurogenic sarcoma. Fifty percent of MPNST occurs in patient with NF1 gene. It typically occurs between the ages of 20 – 50. The clinical presentation is almost the same as schwannoma and neurofibroma except the rapidly enlarging mass within the time spectrum alerts the physician of the possibility of its malignant degeneration. Histological appearance shows dense cellular fascicles alternating with myxoid region. This swirling arrangement is also called marbleized pattern. The cells may be spindle, round or fusiform in shape. Nuclear palisading is very rare compare with schwannoma and occurs in only 10% of cases. Malignancy is suggested by invasion of the surrounding tissue, and vascular structures, nuclear pleomorphism, necrosis, and mitotic activity.


Schwannoma of the foot is a rare tumor which present as solitary swelling of the extremity. Clinicians should always consider schwannoma as a differential diagnosis during approach of mass in the upper or lower limbs. It is essential to differentiate schwannoma with neurofibroma, and also MPNST as each entity is differently managed clinically.


  1. Knight DMA, Birch R, Pringle J. Benign solitary schwannomas: a review of 234 cases. J Bone Joint Surg [Br] 2007;89-B:382-7. (PubMed)
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  3. Berlin SJ. Soft somatic tumors of the Foot: Diagnosis and surgical management. Futura Publishing Co, Mount Kisco, NY: 227, 1976.
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  5. Endo M,Yamamoto H, Harimaya K, Kohashi K, Ishii T, Setsu N et al. Conventional spindle cell-type malignant peripheral nerve sheath tumor arising in a sporadic schwannoma. Hum Pathol. 2013 Dec;44(12):2845-8. (PubMed)

‘Fast Casts’: Evidence Based and Clinical Considerations for Rapid Ponseti Method

by April Sutcliffe1, Kolini Vaea2, John Poulivaati2, Angela Margaretpdflrg Evans3,4

The Foot and Ankle Online Journal 6 (9): 2

The Ponseti method of correction of congenital clubfoot is recognized as the preferred management technique for this pediatric deformity. The original method has been subtly modified over time in response to clinical experience and research findings. Most recently, two randomized controlled trials have shown that less time is needed for each serial cast immobilization. Clinical cases from the Kingdom of Tonga are presented to illustrate the clinical use of more rapid plaster cast changes – the ‘fast casts’ modification incorporating increased manual manipulation time, within the Ponseti method. The Pirani score was used to monitor the clubfoot correction between each plaster cast change for each baby. In all feet the Pirani scores reduced sequentially with shorter periods of casting. Shorter duration of cast immobilization – ‘fast casts’ – can be used with many advantages for the clinical setting. Less time in plaster can at least halve the corrective phase of Ponseti management without compromising results. In addition, there are possible benefits for families from distant locations, for babies being less prone to skin irritations, and less difficult day-to-day baby care related to long leg plaster casts. These factors may benefit compliance and overall treatment outcomes.

Key words: clubfoot, Ponseti, pediatric, foot

Accepted: August, 2013
Published: September, 2013

ISSN 1941-6806
doi: 10.3827/faoj.2013.0609.002

Address correspondence to: Department of Podiatry, Lower Extremity and Gait Studies (LEGS) Research Program, La Trobe University, Bundoora, Melbourne, Australia. Email: angela.evans@latrobe.edu.au

1Sydney Children’s Hospital, High Street, Randwick, Sydney, Australia
2Vaiola Hospital, Tonga
3Department of Podiatry, Lower Extremity and Gait Studies (LEGS) Research Program,
La Trobe University, Bundoora, Melbourne, Australia
4Health and Rehabilitation Research Institute, AUT University, Auckland, New Zealand

The Ponseti method has taken the developed world by storm in the last decade, becoming acknowledged as the optimal treatment for congenital clubfoot deformity.[1,2]

Cited as the most significant and potentially debilitating congenital pediatric orthopaedic deformity, talipes equino varus, has littered the pages of historic tomes, medical journals and textbooks alike.[3] The Egyptian boy king, Tutankhamen; the tragic poet, Lord Byron; and celebrated stage and screen actor, Dudley Moore; eponymously all male, were born and/or lived with clubfoot deformity. [4]

Whilst management with splints, binding, and plaster casts has been evident across the hundreds and thousands of years in which clubfoot deformity is referenced, the 20th century saw such conservative measures subsumed by surgical correction, and notably the posterior medial release (PMR). [5-7] The PMR is a joint invasive procedure, which also severs to lengthen, all the soft tissue structures found contracted on the medial and posterior aspects of the infant clubfoot.[8]

In the 21st century, surgical correction of clubfeet has been firmly denounced.[9] Both retrospective concerns and reviews, and prospectively designed studies have shown the poor outcomes, in terms of pain and function, resulting from the PMR and akin surgical procedures.[7]

Simultaneously, the Ponseti method, developed and named after the orthopedic specialist Ignacio Ponseti[10], has been investigated both retrospectively and in many prospective randomized controlled trials (RCTs), and found not only to give the best clinical outcomes, but to also be a more economical management, when compared to surgery – the rare health care setting finding of a ‘win:win’.[11]

Much investigation of Ponseti’s original method has occurred in the last decade.[7,12,13] Whilst it’s superior outcomes for management of congenital clubfoot has met with universal consensus, this has also resulted in considerable refinement of the technique.[11,14,15]

The original Ponseti method

The duration of each serial plaster cast, a fundamental aspect of the basic weekly casts which made up the original Ponseti method[16] now has good evidence for amendment.

The original method described by Ponseti involves a series of plaster casts changed weekly for a period of five to six weeks, followed by percutaneous elongation of the Achilles tendon and application of a final cast for three weeks. The foot abduction bracing phase, is commenced immediately after the post tenotomy cast is removed.

There is now strong evidence to suggest that accelerated frequency of cast changes has comparable outcomes to those of the original Ponseti method.[17] with the benefit of limiting time spent is casts during the corrective phase of treatment.

The evidence for, and implication of, ‘fast casts’

It was first revealed that casts changed every five days, instead of the originally prescribed seven days, gave the same results – potentially saving ten to 12 days in the initial casting phase.[18] Two more recent RCTs have shown that casts changed twice (even three times) each week attain the same correction as weekly casts. [17, 19]

The halving of the casting phase from an average six weeks to three weeks, without compromising results, has clear advantages. Less time immobilized in plaster casts is intuitively preferable for the baby, and their parents or caregivers. Shorter durations of each corrective cast reduces the likelihood and extent of undetected skin pressure lesions, and at least halves the overall corrective phase, such that babies commence the (virtually) full-time boots and bar phase over three months, at a younger and possibly more amenable age. With the consistently demonstrated and positive correlation between successful use of the maintenance boots and bar, and lessened relapse of clubfoot correction – starting the boots and bar habit earlier within the rapid development that hallmarks infancy – may be more helpful than at first glance considered.[20-22]

How can the notion of ‘fast casts’ be applied clinically, and what are the possible pitfalls as well as benefits?

Illustrative use of the ‘fast casts’ technique

Two cases from Tonga, the country with the world’s highest incidence of congenital clubfoot deformity[23], are included in this review. In Tonga, a pacific island country geographically comprised of numerous islands, clinical use of the ‘fast casts’ method facilitates coordination with the availability of surgical expertise to perform Achilles tenotomies, as well as accelerated progress of babies through the casting stage. Both of the case-study babies were cast and re-cast four times in one week. This is more rapid and intense than might normally occur due to the visit from the off-shore surgeon occurring the following week (the local surgeon has now undertaken training for tenotomy procedures).

Fig 1 Baby J

Figure 1 Baby J, whose data is presented in table 2.


Table 1 Baby J – left congenital clubfoot. The use of ‘fast casts’ saw this baby’s corrected and ready for the tenotomy procedure after six days (4 casts).

Fig 2 Baby S

Figure 2 Baby S, whose data is presented in table 3.


Table 2 Baby S – bilateral congenital clubfeet. The use of ‘fast casts’ corrected the cavus and adduction of the clubfoot deformity, but made no change to the equinus component, which required the tenotomy for correction (as indicated by the initial Pirani score).

As the Tables 1 and 2 show, both babies showed consistent correction of their foot deformity with manipulation and casting. (Fig. 1 and 2) The Pirani scores reduced consistently within the initial corrective phase, showing the value of using this demonstrably reliable and objective measure. Further, the initial Pirani scores of 5 and 5.5 respectively, heralded the very likely need for tenotomies.[24] Indeed, the hindfoot scores equaled or approximated the total Pirani scores after the casting phase, signaling the residual equinus aspect of the deformity. It must be stated that similarly to the findings of the clinical trial by Xu et al[17], that these Tongan cases also underwent ‘more rather than less’ manipulation prior to casting. Whilst the effect of manipulation time has not been formally studied, histological investigation directs maintained loading of ligaments to promote the lengthening or ‘uncrimping’ of these structures.[25] Might it be that more attention to, and time spent, carefully manipulating clubfoot correction is able to render cast time less relevant?

Considerations, variations, and further questions

There are many factors to consider when contemplating the use of ‘fast casts’ as part of the Ponseti clubfoot correction method.

Firstly, there is now very good evidence to support shortening cast time[17] for the typical, congenital clubfoot deformity.

Secondly, the convenience for parents travelling with infants to distant clinics for treatment which necessitates time away from home, work, and family, a common occurrence in developing countries, may be greatly improved.[26-28] If, as on average, a baby requires six casts, the time away from home/work may be reduced from six weeks to two weeks. This could provide great savings for costs incurred whilst living away from home, and time lost from work. In turn, compliance may also benefit.

Thirdly, less time immobilized in plaster is probably advantageous for the baby in terms of reduced skin sore issues, easier bathing, more normal motor development and possibly lessens the risk of osteopenia.[29]

Notable in the current findings on faster casting is the longer manipulation time, (two minutes) specified by Xu, et al., [17], an additional departure from the original Ponseti protocol, and also the long follow up time of this study, as opposed the otherwise similar Malawi trial.[19]

It is important to appreciate that all accelerated casting studies and trials have addressed the typical congenital clubfoot, and that the effects and use in syndromic[11] or complex clubfoot types[30] are unknown.

The application of best available evidence to any health care setting is important, particularly if there are clear benefits to the recipients of this care. The rescheduling of the weekly clubfoot clinic for casting, to at least twice weekly, is now a possible shift in contemporary evidence based practice.


The Ponseti method continues to be the best approach to correction of the typical congenital clubfoot. There is now high-level evidence to support changing casts after three days or less, which greatly reduces the time infants spend immobilized in plaster.

The pre-casting manipulation is important and indications are that more time spent may be beneficial in correcting the clubfoot deformity.

In developing countries where travelling to clinics necessitates time away from home, work, and family, the adoption of ‘fast casts’ can reduce costs to families, and perhaps help to improve compliance and overall outcomes.


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