Osteochondral lesions of the talus.

We report demographic, clinical, and imaging data on 92 patients with osteochondral lesions of the talus collected in one center between 1981 and 1992. All patients reported pain as their primary symptom. Ninety-four percent of the patients reported pain with activity. Physical examination was unhelpful. Using newer imaging techniques (bone scan and computed tomography) and with increased awareness, we have observed a sevenfold increase in the diagnostic frequency of osteochondral lesions of the talus between the years 1981 to 1986 and 1987 to 1992. Bone scan is an excellent screening tool for patients with chronic ankle pain and has 99% sensitivity in depicting osteochondral lesions. Computed tomography demonstrated a previously unclassified lesion, the radiolucent defect, which accounts for 77% of the lesions in this series. We have therefore modified the Berndt and Harty classification system, basing it on radiographic appearance (principally computed tomography) and adding the radiolucent lesion. Fifty-eight patients were treated surgically. Anterior and midtalar lesions are now approached arthroscopically. Surgical treatment of the radiolucent lesion, consisting of curettage and drilling, gives 42% excellent and 32% good results. Pain relief often occurs within months of surgery, but healing of the lesion requires years, and some may persist indefinitely.