尺骨遠位部に発生した類骨骨腫の1例

Osteoid Osteoma Developing in the Distal Ulna. Case Report

　非典型的な症状で発症した尺骨遠位部の類骨骨腫の1例を報告する．われわれが経験した類骨骨腫は，自発痛・夜間痛に乏しく，持続する腫脹・圧痛および前腕の回外制限が特徴的であった．nidusを含んだ骨組織を一塊として切除し，人工骨の移植を行った．術後5カ月で前腕の腫脹・圧痛，および可動域制限は消失した．

　We report a case of osteoid osteoma involving the distal ulna to show its clinical presentation and diagnosis. The diagnosis of osteoid osteoma in the hand and wrist is often delayed because it may present with atypical symptoms. The patient, a 16-year-old high school boy who played handball vigorously, reported progressively limited forearm rotation with minimal pain. Meaningful signs on physical examination were prolonged soft tissue swelling and local tenderness in the distal ulna and limited motion in supination. En block excision of the nidus with artificial bone grafting relieved symptoms and restricted forearm rotation resolved spontaneously 5 months after surgery.