Intraarticular fractures of the calcaneus: value of CT findings in determining prognosis.

The prognosis of intraarticular calcaneal fractures is variable, ranging from severe functional impairment and pain to complete return of normal function. Clinical assessment and CT scanning were performed 1-11 years after fracture in 45 patients (51 fractures) to determine the relationship between the CT findings and clinical status. Conservatively treated (n = 18) and surgically treated (n = 33) fractures were assessed. Clinical assessment included evaluation of subjective parameters (pain, activity, gait, and use of orthotics) and objective measurement of subtalar motion. CT evaluation included assessment of abnormalities in the posterior subtalar joint, loss of calcaneal height, tendon abnormalities, and calcaneocuboid joint abnormalities. A poor clinical outcome, caused by loss of subtalar motion, was more common when CT showed incongruity or degeneration of the posterior facet (p = .04) and when Bohler's angle was decreased (p = .0006). Other CT findings, such as loss of calcaneal height and tendon abnormalities, did not correlate with clinical outcome. An unexpected finding was that surgical screws were intraarticular in eight (24%) of 33 surgically treated patients; however, this finding was not significantly associated with poor clinical outcome. Our findings indicate that the CT findings of degenerative change and incongruity of the posterior subtalar joint correlate significantly with poor clinical outcome.