A double nidus osteoid osteoma in a finger.

The diagnosis of an osteoid osteoma in the proximal phalanx of the right index finger was suggested by the patient's history and the initial radiographs. The diagnosis was histologically confirmed postoperatively. One year later, however, persistent symptoms and typical radiographic findings, again suggested the presence of an osteoid osteoma. Subsequent en bloc resection of the second nidus, which was again histologically confirmed as an osteoid osteoma, was followed by complete resolution of the symptoms. The definitive diagnosis of a double-nidus osteoid osteoma was suggested after careful analysis of the initial radiographs demonstrated the existence of two distinct intracortical nidi.