乳児化膿性肩関節炎による肩関節消失の1例―34年後の上肢機能

Disappearance of the Shoulder Joint following Infantile Septic Arthritis. Function of the Upper Limb 34 Years Later

　乳児期に化膿性肩関節炎を発症し，その後34年を経過して肩関節の形態を失った症例の上肢の機能を分析した．症例は34歳の男性で，右に15cmの上腕の短縮，右肩に挙上90°の可動域制限がみられた．X線上肩甲上腕関節は消失し，MRI上肩関節は瘢痕組織により置換されていた．小児化膿性肩関節炎の機能的予後は良好であるとされているが，本症例では骨髄炎による上腕長の短縮と肩関節の消失による高度の機能障害が残った．しかし患肢は非利き手として，日常生活に支障のない程度の機能を有していた．

　The function of a shoulder affected by infantile septic arthritis that had been treated by incisional drainage 4 months after the onset of infection was evaluated in a 34-year-old male. The patient had used his right upper extremity as the non-dominant side. Radiography had shown that the glenohumeral joint had disappeared in early childhood, and his right arm was 15cm shorter that the left. An MRI study at 34 years of age revealed that the glenohumeral joint had been replaced by scar tissue. Contrary to other reports that showed relatively good functional outcome of infantile shoulder arthritis, our patient had seriously impaired shoulder function (Japan Orthopedic Association Shoulder Score of 76 points out of a possible 100) because of the shortening of the arm and restricted range of the motion of the shoulder joint to 90 degrees of elevation and 0 degrees of external rotation. The importance of early surgical treatment of infantile septic arthritis of the shoulder must be emphasized to preserve the anatomy and function of the affected limb.