急速破壊を呈した𦙾骨内顆骨壊死の1例

Rapidly Destructive Ostenecrosis of Medial Tibial Plateau ；A case Report

　抄録：𦙾骨内顆骨壊死は大腿骨内顆骨壊死に比べて稀な疾患である．今回われわれは急速に骨破壊を呈した𦙾骨内顆骨壊死の1例を経験したので報告する．症例は73歳，女性で外来通院中，歩行困難になり，単純X線上𦙾骨内顆骨壊死と判断し，関節鏡を施行した結果，内側𦙾骨高原は陥凹を，外側𦙾骨高原は軟骨欠損を認めたため，人工膝関節置換術（以下，TKA）を施行した．術後3年10カ月の現在，右膝の可動域制限は認めるものの日整会変形性膝関節症治療成績判定基準（以下，JOAスコア）では80点で，杖なしの歩行も可能であり，経過良好である．

　Most of osteonecrosis of the knee has been reported to occur due to the medial femoral condyle. The incidence of osteonecrosis of the medial tibial plateau is rare. We report a case of rapidly destructive osteonecrosis of the medial tibial plateau in a 73-year-old woman. She treated conservatively in her right knee pain at our outpatient clinic from April 1997. Fifteen months later, she could not walk because of the increased knee pain. Arthroscopy of her right knee revealed the collapse of the medial tibial plateau and the defect of the cartilage of the lateral tibial plateau.

　Therefore, she had a total knee arthroplasty (TKA). At the time of the most recent evaluation, which was 46months after the operation and 61months after the initial examination, she walked well without support and had no pain. The range of motion of the knee was 15 to 90 degrees. The Japanese Orthopaedic Association (JOA) score was 80 points.