RESUMO
Osteoblastoma is a benign bone tumor that can spread aggressively and is commonly found in the spine and long bones. When present in other areas of the body, it can be difficult to diagnose. While this tumor is rarely found in the hand, in reported cases, it typically presents with pain. Treatment is usually curettage and marginal excision. We report a rare case of osteoblastoma in the fifth proximal phalanx of the left hand in a 14-year-old right-handed female, presenting as a painless, progressively growing mass with associated flexion contracture over a seven-month period, with no history of trauma. An excision biopsy with curettage was performed, and histopathologic examination confirmed the diagnosis of osteoblastoma. This is a rare case of osteoblastoma of the proximal phalanx presenting as a painless mass in the finger with a progressive flexion contracture. Histopathologic examination is important in diagnosing osteoblastoma to determine the appropriate treatment and surgery. Post-operatively, close monitoring is important due to the high recurrence rates in these tumors.