AAOS/ABOS Foot & Ankle Board Review (Set 2): Ankle Fractures, Hallux Valgus & PTTD MCQs | 2009

The patient has necrotizing fasciitis, a rare and sometimes fatal disease that has many different etiologies. Signs that this is not a normal infection are the worsening clinical symptoms despite IV antibiotics and the systemic symptoms. He needs urgent surgical care before he becomes completely septic and unstable. He needs very aggressive debridement of his tissues. Hyperbaric oxygen and immunoglobulins are only anecdotally helpful, and would only be used after surgery. Fontes RA, Ogilvie CM, Miclau T: Necrotizing soft-tissue infections. J Am Acad Orthop Surg 2000;8:151-158.

This deformity is early in the disease process. The foot is still flexible, as evidenced by correction with the Coleman block test. A simple dorsiflexion osteotomy of the first metatarsal should provide a plantigrade foot. More complex osteotomies are required later in the disease process when the foot is not flexible and the deformity does not correct with the Coleman block test. The patient may also require a tibialis anterior transfer later in the disease process but not at the present time. Richardson EG (ed): Orthopaedic Knowledge Upate: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 135-144.

Whereas it is difficult to distinguish between cellulitis, septic joint, osteomyelitis, and early Eichenholtz stage 1 Charcot, the presence of a fracture in the absence of ulcerations with a normal WBC count and serum glucose strongly indicates that the described symptoms are due to an early Charcot process alone. A technetium Tc 99m scan alone would not be helpful; however, the addition of a sulfur colloid marrow scan or indium In 111 scan may be more specific to rule out infection, though it is not warranted here. Total contact casting with non-weight-bearing or limited weight bearing during Eichenholtz stage 1 when the foot is warm, erythematous, and swollen is advised to help prevent deformity. Alternatively, stabilization with pneumatic bracing may also be considered. While some authors have proposed early fixation or arthrodesis for Eichenholtz stage 1, the gold standard is still total contact casting with no to limited weight bearing until the swelling resolves and evidence of consolidation is seen on radiographs. Trepman E, Nihal A, Pinzur MS: Current topics review: Charcot neuropathy of the foot and ankle. Foot Ankle Int 2005;26:46-63. Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2003, pp 123-134.

Diabetes mellitus, obesity, and exposure to steroids have all been associated with the development of Achilles tendinopathy. In addition, Achilles tendinopathy has been associated with a history of hormone replacement therapy and the use of oral contraceptives. Quinolone antibiotics have also been linked to Achilles tendinopathy. Holmes GB, Lin J: Etiologic factors associated with symptomatic Achilles tendinopathy. Foot Ankle Int 2006;27:952-959.

The extruded talus should be placed in sterile bacitracin solution, irrigated thoroughly, gently debrided, and immediately replanted in the OR. Open reduction and internal fixation of the talar fracture may be attempted immediately depending on the soft-tissue envelope, or delayed after soft-tissue stabilization with an external fixator. A retrospective study of 19 patients with an extruded talus reported that 12 patients had no subsequent surgery after definitive fixation, 7 had subsequent procedures, and 2 patients developed infections that were treated successfully at an average of 42-month follow-up. Successful outcome in this series was attributed to multiple debridements, soft-tissue stabilization, and primary wound closure. Smith CS, Nork SE, Sangeorzan BJ: The extruded talus: Results of reimplantation. J Bone Joint Surg Am 2006;88:2418-2424. Brewster NT, Maffulli N: Reimplantation of the totally extruded talus. J Orthop Trauma 1997;11:42-45.

The patient has a malunion of an attempted open reduction of a Lisfranc dislocation. The pain occurs during the terminal stance phase of gait as load is being transferred from the hindfoot to the forefoot. The bending moment can be best neutralized with shoe modification with a cushioned heel and rocker sole, which best unloads the tarsal-metatarsal junction. Bono CM, Berberian WS: Orthotic devices: Degenerative disorders of the foot and ankle. Foot Ankle Clin 2001;6:329-340.

Differentiating between a midfoot sprain and Lisfranc diastasis is critical in the management of the athlete with an acute injury to the midfoot. Greater than 2 mm of displacement between the first and second metatarsals on a weight-bearing radiograph is an indication for anatomic reduction with internal fixation of the tarsometatarsal joints. If no subluxation is noted, treatment should consist of a non-weight-bearing cast for 6 weeks, followed by a gradual return to activity. Mizel MS, Miller RA, Scioli MW (eds): Orthopaedic Knowledge Update: Foot and Ankle 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 39-54.

The patient has a dynamic varus deformity secondary to spasticity of the tibialis anterior during stance phase with inverter/everter imbalance. The patient still has active motion of the tibialis anterior; therefore, an out-of-phase posterior tibial tendon transfer should not be performed. The same is true of the Bridle procedure. Transfer of the posterior tibialis in this patient may also result in subsequent planovalgus deformity. Lengthening of the Achilles tendon through a percutaneous tenotomy will restore dorsiflexion and decrease clonus from the stretch response. If adequate dorsiflexion is not obtained intraoperatively, then posterior tibialis tendon lengthening may be considered. A split tibialis anterior tendon transfer to the lateral cuneiform, or, transfer of the entire tendon to the cuneiform should correct the varus component and compensate for the weakened peroneals. Yamamoto H, Okumura S, Morita S, et al: Surgical correction of foot deformities after stroke. Clin Orthop Relat Res 1992;282:213-218. Piazza SJ, Adamson RL, Moran MF, et al: Effects on tensioning errors in split transfers of tibialis anterior and posterior tendons. J Bone Joint Surg Am 2003;85:858-865.

Persistent pain at the fracture site in the absence of infection is most likely due to a nonunion, best detected by CT. Walsh and DiGiovanni reported on a series of closed rotational fibular fractures in which nonunions were detected by CT in the absence of standard ankle radiographic findings. Repeat immobilization would not be appropriate at this late date. Pain management/sympathetic blocks would be considered if the patient displayed pain with light touch and disproportionate pain consistent with a complex mediated pain syndrome. Acupuncture would be expected to be of limited benefit. Walsh EF, DiGiovanni C: Fibular nonunion after closed rotational ankle fracture. Foot Ankle Int 2004;25:488-495.

Sural nerve entrapment is the major risk of percutaneous repair. A small mini-open technique with a suture guide can obviate that issue. Re-rupture rates after surgical repair are approximately 3%. Infection and wound problems are rarely encountered with percutaneous repair; they are issues with open repair. Aracil J, Pina A, Lozano JA, et al: Percutaneous suture of Achilles tendon ruptures. Foot Ankle 1992;13:350-351. Sutherland A, Maffulli N: A modified technique of percutaneous repair of the ruptured Achilles tendon. Oper Orthop Traumatol 1998;10:50-58.

Weinstein reported on 31 patients (45 feet) with congenital metatarsus adductus followed for an average of 33 years. Twenty-nine feet had moderate to severe deformities treated with manipulation and casting with a 90% success rate. In a young child, surgery is not indicated until nonsurgical management has failed. In patients 2 to 4 years of age, tarsometatarsal capsulotomies are indicated, whereas multiple metatarsal osteotomies are reserved for recalcitrant deformities in children older than 4 years of age. Mild or moderate metatarsus adductus that is passively correctable will resolve without treatment. Beaty J: Congenital anomalies of the lower extremity, in Canale ST (ed): Campbell's Operative Orthopaedics, ed 10. Philadelphia PA, Mosby, 2003, pp 983-988. Katz K, David R, Soudry M: Below-knee plaster cast for the treatment of metatarsus adductus. J Pediatr Orthop 1999;19:49-50.

Arthrodesis of any of the ankle or hindfoot joints should be reserved for fixed deformities or end-stage degenerative arthritis. Achilles tendon lengthening is necessary to correct the equinus and to improve dorsiflexion-plantar flexion balance. Similarly, transfer of the posterior tibialis tendon reduces both plantar flexion and inversion torque. Hansen ST: Function Reconstruction of the Foot and Ankle. Philadelphia, PA, Lippincott Williams & Wilkins, 2000, pp 442-447.

Triplane fractures generally occur in children who are near skeletal maturity. The injury is generally caused by a supination external rotation mechanism. The number of fracture fragments present (two or three) depends on what part of the physes is closed at the time of injury. Articular congruity is the major concern in the management of these injuries since the patient has almost reached skeletal maturity. The goal is to restore articular congruity to minimize the development of posttraumatic arthritis. Vaccaro A (ed): Orthopaedic Knowledge Update 8. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2005, pp 757-765. Kling TF Jr, Bright RW, Hensinger RN: Distal tibial physeal fractures in children that may require open reduction. J Bone Joint Surg Am 1984;66:647-657.

The patient has end-stage midfoot arthritis, with a secondary flatfoot deformity through the midfoot. The ability to perform a single limb heel rise indicates that the posterior tibial tendon is functioning, and the weight-bearing radiographs show normal calcaneal pitch and talar head coverage, thus confirming that the flatfoot deformity is isolated to the midfoot. Therefore, the most appropriate treatment is medial column arthrodesis and heel cord lengthening. The other listed procedures are not indicated because they are used in the management of adult flatfoot from posterior tibial tendon insufficiency. Toolan BC: Midfoot arthrodesis: Challenges and treatment alternatives. Foot Ankle Clin 2002;7:75-93.

All but the Moberg osteotomy are capable of providing pain relief; however, arthrodesis offers the best long-term results and restores weight bearing and propulsion function to the first ray. Machacek F Jr, Easley ME, Gruber F, et al: Salvage of a failed Keller resection arthroplasty. J Bone Joint Surg Am 2004;86:1131-1138.

The sural nerve runs with the small saphenous vein on the posterior leg just lateral to the Achilles tendon. It is formed by contributions from both the tibial and common peroneal nerves and provides sensation on the dorso-lateral aspect of the foot. Aktan Ikiz ZA, Ucerler H, Bilge O: The anatomic features of the sural nerve with an emphasis on its clinical importance. Foot Ankle Int 2005;26:560-567.

The radiographs reveal nonunion of a talar neck fracture. There is no radiographic evidence of osteonecrosis or significant degenerative arthritis. The results of talectomy are suboptimal. Arthrodesis would be indicated for degenerative arthritis. Revision ORIF is feasible and preserves motion. A vascularized graft should be considered whenever osteonecrosis is present, but the talar body appears viable in this case. Calvert E, Younger A, Penner M: Post talus neck fracture reconstruction. Foot Ankle Clin 2007;12:137-151.

Eccentric gastrocsoleus strengthening (especially with heavy loads) consistently has been shown to be superior in the management of Achilles tendinopathy. Decreases in pain and increases in strength have been demonstrated despite the frequently refractory nature of this condition. Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2003, pp 91-102.

This is an example of tethering of the flexor hallucis longus/flexor digitorum longus (FHL/FDL) to the fracture site. Additional time and/or physical therapy and bracing would not be expected to be of benefit. Release of the FHL and FDL from the fracture site or retromalleolar lengthening will address the posttraumatic claw toe deformity and Achilles tendon lengthening will address the mild equinus. Posterior tibial tendon transfer is not appropriate as the patient demonstrates a normal heel rise. Midfoot releases and hallux fusion are also not indicated. Feeny MS, Williams RL, Stephens MM: Selective lengthening of the proximal flexor tendon in the management of acquired claw toes. J Bone Joint Surg Br 2001;83:335-338.

The ankle dorsiflexor muscles have been denervated for too long a period to expect reinnervation to be successful. Even if the extensor hallucis longus tendon was functional, it is unlikely to have sufficient strength to achieve dynamic ankle dorsiflexion. The tibialis posterior tendon transfer has been shown to predictably achieve these goals in a high percentage of patients. Successful ankle fusion is likely to fail with time due to the development of forefoot equinus. Pinzur MS, Kett N, Trilla M: Combined anteroposterior tibial tendon transfer in post-traumatic peroneal palsy. Foot Ankle 1988;8:27l-275.

The radiographs and CT scans show a displaced intra-articular calcaneal fracture, with loss of calcaneal height and length. Recent multicenter, randomized, prospective studies suggest that surgical treatment of displaced intra-articular calcaneal fractures is associated with an almost six-fold decrease in the risk of posttraumatic subtalar arthritis (necessitating subtalar arthrodesis) compared to nonsurgical treatment. Despite ongoing controversy, surgical treatment has not been shown to be advantageous with respect to activity, time to return to work, or subtalar joint range of motion. A nonunion of a calcaneal fracture is exceedingly rare regardless of the treatment method. Buckley R, Tough S, McCormack R, et al: Operative compared with nonoperative treatment of displaced intra-articular calcaneal fractures: A prospective, randomized, controlled multicenter trial. J Bone Joint Surg Am 2002;84:1733-1744.

A flexor digitorum longus transfer, while not as strong as the peroneals, improves the tendon balance and maintains hindfoot mobility. Subtalar fusion is a salvage procedure. Posterior tibial tendon transfer compromises inversion strength and arch height. Functional absence of the peroneals results in an imbalance that could lead to forefoot varus. Redfern D, Myerson M: The management of concomitant tears of the peroneus longus and brevis tendons. Foot Ankle Int 2004;25:695-707.

Ultrasound is best at imaging abrupt changes in the density of adjacent tissue and therefore is best at imaging wood in the soft tissues of the foot. Mizel MS, Steinmetz ND, Trepman E: Detection of wooden foreign bodies in muscle tissue: Experimental comparison of computed tomography, magnetic resonance imaging, and ultrasonography. Foot Ankle Int 1994;15:437-443.

The patient sustained a type I unstable fracture that requires debridement of superficial fragments from the sole and surgical stabilization. Low-velocity wounds less than 8 hours old are considered type I open fractures. In contrast, gunshot wounds with associated fractures more than 8 hours old are considered type II open fractures using the Gustilo and Anderson classification. Gustilo type I stable fractures due to gunshot wounds and seen within 8 hours can be treated with tetanus toxoid (if no history of immunization or booster within 5 years), surface irrigation, and casting or a hard sole shoe. Antibiotics are not required unless gross contamination is present. However, if the extent of contamination is unclear, or if a joint is penetrated, then routine antibiotic prophylaxis is recommended. Indications for surgery include: articular involvement, unstable fractures, presentation 8 or more hours after injury, tendon involvement, and superficial fragments in the palm or sole. Type I unstable fractures may be stabilized with internal or external fixation. Type II unstable fractures should be treated with external fixation and repeat debridements until clean. Holmes GB Jr: Gunshot wounds of the foot. Clin Orthop Relat Res 2003;408:86-91.

The most frequently described entrapment of the deep peroneal nerve is the anterior tarsal tunnel syndrome. This syndrome refers to entrapment of the deep peroneal nerve under the inferior extensor retinaculum. Entrapment can also occur as the nerve passes under the tendon of the extensor hallucis brevis. Compression by underlying dorsal osteophytes of the talonavicular joint and an os intermetatarseum (between the bases of the first and second metatarsals) have previously been described in runners. Kopell HP, Thompson WA: Peripheral entrapment neuropathies of the lower extremity. N Engl J Med 1960;262:56-60.