Results of in situ subtalar arthrodesis for late sequelae of calcaneus fractures.

A retrospective review was performed on all patients who had an in situ subtalar arthrodesis for painful sequelae of calcaneus fractures between 1989 and 1994. Nineteen feet were available for evaluation, with a mean follow-up of 27 months (range, 12-62 months). Lateral calcaneal wall decompression was performed in seven feet. Although loss of ankle dorsiflexion was associated with anterior ankle tenderness, loss of ankle dorsiflexion was not correlated with either talar declination angles or talar height differences. There was no correlation between American Orthopaedic Foot and Ankle Society hindfoot score and talar declination, talar height, or calcaneal width. Peroneal tendon/subfibular impingement, ankle tenderness, sural nerve injury, and patient smoking were all statistically associated with lower scores. The calcaneocuboid joint was frequently involved in the fracture but was not painful at follow-up. Late pain after a calcaneal fracture is not caused by only subtalar arthrosis. Radiographic criteria alone cannot be relied upon for surgical decision making. Careful physical evaluation should be used to determine sources of pain. Distraction arthrodesis should be considered only if findings of anterior ankle impingement are present. If sural nerve symptoms are present, a sural neurectomy may be added to the procedure. Pain localized to the plantar fat pad should be managed nonoperatively. Radiographic changes in the calcaneocuboid joint rarely require surgical intervention. Based on these results, in situ subtalar arthrodesis with lateral wall decompression is the procedure of choice in most cases of subtalar traumatic arthritis with lateral wall impingement.