Subtalar Arthrodesis for Malunited OS Calcis Fractures

The author used a modified method of distraction subtalar fusion to treat problems of the malunion of calcaneus, including subtalar arthritis, loss of calcaneal height with dorsiflexion of the talus, widening of the heel with calcaneofibular impingement, varus/valgus deformity of the hindfoot, and difficulty in wearing shoes. Distracting the subtalar joint with a wedge bone graft could restore the lateral talocalcaneal alignment, add calcaneal height, correct the varus deformity of the hindfoot and enhance subtalar fusion. Osteotomy of the lateral bulging cortex decompressed the tenting of the peroneal tendons and sural nerve, cured the calcaneofibular abutment and narrowed the calcaneal width for shoes fitting. From 1988 to 1992, 34 patients with calcaneal malunion and severe deformity were treated by this method. Thirty-two of the 34 were available for functional and radiographic follow-up period at this review was 54 months. Solid subtalar fusion was achieved in 31of the 32. Only one case received secondary bone grafting to achieve fusion. The meanunion period was 8.2 weeks (range, 6 to 16). These patients, 26 were pain free with full activity, 4 had mild pain and 2 had moderate pain; 24 returned to previous work and 8 changed work. The average gain of calcaneal height was 1.1 cm and the lateral talocalcaneal angle increased 11 degrees in average. The neutral hindfoot alignment was achieved in 26 cases. Overall, 28 of the 32 patients had good to excellent results, by clinical assessment.