8. Foot and Ankle MCQs

The clinical photograph shows a rocker-bottom deformity, and the lateral radiograph suggests a congenital vertical talus deformity. A lateral radiograph of the foot in maximum plantar flexion is needed to demonstrate the fixed position of the deformity with malalignment of the talar-metatarsal axis. A fixed dislocation of the navicular on the talus differentiates a congenital vertical talus from the oblique talus with talonavicular subluxation. Kumar SJ, Cowell HR, Ramsey PL: Vertical and oblique talus. Instr Course Lect 1982;31:235-251. Kodros SA, Dias LS: Single-stage correction of congenital vertical talus. J Pediatr Orthop 1999;19:42-48.

The radiographs show a comminuted talar body fracture. The goal of treatment is to minimize the risks of posttraumatic arthrosis of the ankle and subtalar joint and to maintain vascularity. Open reduction and internal fixation with an attempt at anatomic reduction will lead to improved outcomes. Attempting to repair this fracture via an arthrotomy only is extremely difficult, and the addition of a medial malleolar osteotomy is warranted. A limited anterior lateral arthrotomy with minimal soft-tissue stripping may assist with fixation of anterior-lateral and lateral fragments and allow better assessment of reduction of the major fracture line. Nonsurgical care would lead to inadequate reduction and increased risk of both ankle and hindfoot arthrosis. Talectomy and primary ankle and hindfoot arthrodesis should not be performed as primary surgical reconstructive options in this closed injury pattern. Sanders R: Fractures and fracture-dislocations of the talus, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, pp 1465-1518.

The best initial test for this patient is to assess the vascular supply to the foot. An elderly smoker with diabetes mellitus has a high risk of peripheral vascular disease. Decreased weight bearing has not been successful. Although a bone scan might be helpful, it would take secondary consideration to the patient's vascular supply, especially in the absence of any acute infection. Monofilament testing would help diagnosis neuropathy, which is a root cause behind the ulcer forming, but does not prevent it from healing. The Thompson's test is used to diagnosis an Achilles tendon rupture.

The abductor hallucis muscle is the most medial structure. The posterior tibial tendon and the flexor digitorum longus tendon lie more cephalad to the sustentaculum tali. There is a groove under the sustentaculum for the flexor hallucis longus tendon. Subchondral lag screws placed across the posterior facet exit the medial side of the calcaneus in this groove. Just medial to the flexor hallucis longus tendon is the neurovascular bundle. A screw that is out of the bone a short distance can cause triggering of the flexor hallucis longus tendon. Patients will report loss of great toe excursion in the early postoperative period. Accurate measurement of subchondral lag screw length avoids this complication. Hollinshead WH: Anatomy for Surgeons, ed 3. Philadelphia, PA, Harper and Row, 1982, pp 802-852. Rosenberg AS, Cheung Y: Diagnostic imaging of the ankle and foot, in Jahss MH (ed): Disorders of the Foot and Ankle, ed 2. Philadelphia, PA, WB Saunders, 1991, pp 109-154.

Because there is a significant possibility that the patient may have a fracture of the lateral process of the talus, there is some disagreement as to the best radiographic study to identify this injury. A CT scan is an appropriate diagnostic tool to visualize the fracture and identify any displacement. Displaced lateral process fractures are best treated surgically. Kirkpatrick DP, Hunter RE, Janes PC, Mastrangelo J, Nicholas RA: The snowboarder's foot and ankle. Am J Sports Med 1998;26:271-277.

The radiograph and MRI scan show elongation and fragmentation of the os peroneum. Although casting, orthoses, and steroid injection may relieve symptoms, excision of the os peroneum and primary repair when necessary, with or without tenodesis of the peroneus longus to the peroneus brevis, have been shown to produce excellent results. Haddad SL: Disorders of tendons: Peroneal tendon dysfunction, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, pp 812-817.

The history and radiographs indicate a Lisfranc fracture-dislocation of the foot. The radiographs show the classic "fleck sign," which is an avulsion of the Lisfranc ligament from the base of the second metatarsal. Most authors recommend open reduction and internal fixation of this injury. Closed reduction can be attempted, but anatomic reduction is unlikely because of the interposed bone fragments and soft tissues. Standard radiographs are not reliable in identifying 1 to 2 mm of subluxation of the tarsometatarsal joint. The tarsometatarsal joint has a poor tolerance to even mild subluxation, and the resulting decrease in joint contact area increases the likelihood of posttraumatic arthritis. Open reduction with the joint visible allows more anatomic reduction and internal fixation of larger osteochondral fragments or excision of smaller interposed fragments. Bellabarba C, Sanders R: Dislocations of the foot, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, vol 2, pp 1539-1558.

The best results after dislocations of the tarsometatarsal joints are seen with anatomic reduction; this is best achieved by open reduction and maintained with internal fixation with either pins or screws. Open reduction provides a means of debriding small bony fragments from the joint and allowing direct inspection of the reduction. Associated crush or shearing fractures of the cuboid or tarsal navicula are signs that suggest a Lisfranc injury. Because patients can function quite well despite the development of arthrosis in the Lisfranc joint, primary arthrodesis is not indicated in the management of this injury. Resch S, Stenstrom A: The treatment of tarsometatarsal injuries. Foot Ankle 1990;11:117-123. Schenck RC Jr, Heckman JD: Fractures and dislocations of the forefoot: Operative and nonoperative treatment. J Am Acad Orthop Surg 1995;3:70-78.

This injury pattern is one of a direct trauma to the mid aspect of the foot. Without additional forces involved, capsular ligamentous injury is not anticipated; therefore, the injury should be a stable pattern. Treatment should consist of protected weight bearing as tolerated in a walking boot or walking cast. Surgical intervention with open reduction and internal fixation, percutaneous pinning, or open reduction and internal fixation with primary tarsometatarsal joint fusion is not indicated with this pattern of injury. The use of external bone stimulation in this acute fracture setting is not indicated. With injuries to the midfoot area where the exact mechanism of injury is uncertain, there should be a high index of suspicion for an associated injury to the tarsometatarsal joint, and standing radiographs or stress radiographs should be obtained. Myerson MS: Foot and Ankle Disorders. Philadelphia, PA, WB Saunders, 2000, pp 1265-1296.

The patient has advanced arthrosis of the midfoot, and orthotic management has failed to provide relief. Therefore, the treatment of choice is midfoot arthrodesis. Shock wave treatment has not been shown to be beneficial for arthritis. An ankle-foot orthosis would not be appropriate based on findings of a normal ankle joint. Triple arthrodesis would not be helpful because the hindfoot joint is not affected in a Lisfranc injury. Sangeorzan BJ, Veith GR, Hansen ST Jr: Salvage of Lisfranc's tarsometatarsal joints by arthrodesis. Foot Ankle 1990;10:193-200.

The patient has cavus feet with minimal clinical symptoms. At this stage, conservative management is preferred. The use of a molded orthosis will allow better support of the midfoot and provide cushioning of the forefoot. This will most likely result in long-term relief. In more advanced cases with forefoot callus formation, Achilles tendon lengthening or calcaneal osteotomy and Steindler stripping are effective in correcting the cavus deformity. In the presence of arthritic changes in the hindfoot, a triple arthrodesis with corrective bone resection may be necessary. Janisse DJ: Indications and prescriptions for orthoses in sports. Orthop Clin North Am 1994;25:95-107.

Because the patient has a hallux valgus with increased intermetatarsal and hallux valgus angles and advanced degenerative arthritis of the joint, arthrodesis of the first metatarsophalangeal joint will provide the most predictable pain-free result. An attempt to correct the bunion with a bunionectomy or osteotomy would most likely fail. The hallux valgus and advanced degenerative changes put the foot beyond the indications for a cheilectomy. Long-term results with silicone arthroplasty have been disappointing. Mann RA: Disorders of the first metatarsophalangeal joint. J Am Acad Orthop Surg 1995;3:34-43.

Intra-articular fractures of the calcaneus often include depression of the posterior facet of the subtalar joint. This can lead to dorsiflexion of the talus because of diminished height posteriorly. In a weight-bearing position, the dorsal surface of the talar neck can impinge against the distal tibia, causing anterior ankle pain. In addition, posttraumatic arthritis of the subtalar joint typically occurs after a calcaneus fracture. The patient's symptoms are consistent with both anterior ankle impingement and subtalar degenerative arthritis. The Bohler angle, approximately 15 degrees, confirms depression of the posterior facet. Distraction subtalar arthrodesis with a corticocancellous bone block autograft will improve talar declination, decrease anterior impingement, and address the subtalar degenerative arthritis simultaneously. Rammelt S, Grass R, Zawadski T, et al: Foot function after subtalar distraction bone-block arthrodesis: A prospective study. J Bone Joint Surg Br 2004;86:659-668.

The patient has a zone 1 base of the fifth metatarsal fracture (Pseudojones) that represents a less serious injury compared to zone 2 and 3 fractures with regard to healing potential. Treatment is symptomatic and casting is not necessary. These fractures are well treated with a hard-soled shoe for comfort and weight bearing as tolerated. Surgical intervention is not warranted. Vorlat P, Achtergael W, Haentjens P: Predictors of outcome of non-displaced fractures of the base of the fifth metatarsal. Int Orthop 2007;31:5-10. Wiener BD, Linder JF, Giattini JF: Treatment of fractures of the fifth metatarsal: A prospective study. Foot Ankle Int 1997;18:267-269.

The patient has severe calcifications at the insertion of the Achilles tendon. Failure to address the Haglund's exostosis and the calcifications will leave the patient with persistent pain. Steroids should not be injected directly into the tendon because of the increased risk of tendon rupture. Shock wave treatment may have some value in treating plantar fasciitis, but its efficacy has not been documented with insertional calcifications and Haglund's exostosis treatment. Brisement is injection of saline solution around the Achilles tendon in an attempt to decompress the peritenon. This may be valuable in intrasubstance Achilles tendinosis or peritendinitis but has no value with insertional disease. Symptoms persisting beyond 6 months are difficult to treat nonsurgically; therefore, the appropriate treatment protocol is aggressive and must address all pathology. The patient may not be able to run at the level achieved prior to surgery, but the goal of the surgery is pain relief. Clain M, Baxter D: Achilles tendinitis. Foot Ankle 1992;13:482-487. Schepsis A, Wagner C, Leach R: Surgical management of Achilles tendon overuse injuries: A long-term follow-up study. Am J Sports Med 1994;22:611-619. Schepsis A, Leach R: Surgical management of Achilles tendinitis. Am J Sports Med 1987;15:308-315.

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.

Following a calcaneal fracture, the patient has severe subtalar arthritis with loss of talar declination and shortening of the heel; therefore, the treatment of choice is subtalar distraction arthrodesis. Orthotics will not provide significant relief as bracing has failed. Ankle arthrodesis will not be beneficial because the arthritis is in the subtalar joint. Subtalar arthroscopy would only be helpful for a small area of arthrosis, and calcaneal osteotomy would not be beneficial given the extent of the arthritis of the subtalar joint.

This pattern of injury is consistent with an unrecognized compartment syndrome of the anterior and lateral compartments. Transfer of the PTT through a long incision in the interosseous membrane corrects the foot drop deformity and allows adequate dorsiflexion provided that the tendon to be transferred has a strength of 5/5. Muscles/tendons typically lose one grade of strength after transfer. Transfer into the tendons at the level of the ankle prevents overtensioning or pullout of a PTT tendon that is not long enough. Debridement of the scarred muscle in the anterior compartment decreases the risk of scarring down to the tendon transfer. Transfer of the peroneus longus is not preferred given its relative lack of strength and line of pull. Continued therapy and bracing are unlikely to lead to further improvement at 2 years after injury. An ankle fusion would correct the foot drop but would not address the tendon imbalances between the tibialis anterior and the peroneus longus, and the PTT and the peroneus brevis.

The bifurcate ligament bifurcates to connect the dorsal aspect of the anterior process of the calcaneus to both the cuboid and the navicular. Inversion injuries on the side of the foot can result in avulsion fractures (arrow) of the anterior process of the calcaneus. Sarrafian SK: Anatomy of the Foot and Ankle: Descriptive, Topographic, Functional, ed 2. New York, NY, Lippincott, 1993, p 192.

The CT scan reveals an avulsion of the dorsal beak of the anterior process of the calcaneus. This common fracture is an avulsion of the origin of the bifurcate ligament, which runs from the anterior calcaneal process to both the cuboid and the lateral aspect of the navicular. An inversion mechanism is common, and the fracture is often missed in evaluation for a suspected ankle sprain. MRI may be useful in the diagnosis of these occult injuries, and suspicion should be present when tenderness exists over the superior portion of the anterior process of the calcaneus.