Osteoid osteoma of the carpal bones. Two case reports.

Osteoid osteoma rarely develops in the wrist. The symptoms resemble atypical tenosynovitis, with variations according to the location of the tumor. As a result, diagnostic wanderings are common. In addition, the pain may seem related to an injury, as illustrated by two cases reported herein. Conventional investigations often fail to contribute to the diagnosis. The most specific investigation is thin-slice computed tomography (CT), which can be coupled to magnetic resonance imaging. CT typically visualizes a round lucency surrounded by a rim of sclerosis; in addition, CT shows the exact location of the tumor, particularly relative to neighboring joints. Complete excision of the nidus must be achieved to ensure a permanent cure. Same-stage carpal bone fusion may be required in patients with extensive joint involvement.