A Subperiosteal Proximal Phalanx Osteoid Osteoma: A Challenging Diagnosis.

A relatively rare tumor, osteoid osteoma most commonly affects the lower extremity. In 10% of the cases, it can affect the hand and wrist. We present a case of osteoid osteoma in the proximal phalanx of ring finger that was initially misdiagnosed as a soft tissue lesion. The soft tissue lesion was resected, but the symptoms recurred shortly thereafter, leading to repeat diagnostic workup. Despite X-rays, magnetic resonance imaging, and tissue biopsy, the diagnosis remained elusive until surgical re-exploration. Based on the lessons learned from this case and the experience reported in literature, we discuss the intricate nature of osteoid osteoma diagnosis in the hand, the obstacles often encountered, and how to approach these challenging patients in a stepwise and critical fashion.