Phalangeal Osteoid Osteoma of Thumb.

Osteoid osteomas are typically benign osteoblastic bone tumors. Patients often present in their twenties with progressively increasing pain that is worse at night and relieved with nonsteroidal anti-inflammatory drugs. These lesions rarely occur in the hand or wrist; however, when those are involved, the proximal phalanx is the most common location and the index finger is the most commonly affected digit. Lesions affecting the distal phalanges are least likely to occur and the thumb is least likely to be affected. Osteoid osteomas of the distal phalanges can cause great diagnostic challenges. They often present with atypical radiographic and physical examination findings. Although rare, osteoid osteomas of the distal phalanx can be a major cause of digit enlargement and pain. In a patient with a painful and/or swollen digit, the diagnosis should be considered.