Occult osteochondral fractures of the subtalar joint: a review of 10 patients.

Ten patients were treated who had occult osteochondral fractures of the subtalar joint that were not associated with dislocation. Nine osteochondral fractures involved the posterior facet. Seven patients had a stiff and painful subtalar joint, and an arthrodesis was performed. Three patients presented with adequate subtalar joint motion and were treated with physiotherapy. Detection of osteochondral fractures of the subtalar joint is difficult. The "early warning" signs are massive swelling without definitive bone injury on radiographic examination, and a failure to regain subtalar motion after a period of immobilization. Confirmatory evidence is obtained from CT scans or MRI. Initially, aggressive physiotherapy should be considered. Arthrodesis should be used for patients who remain symptomatic.