1998 年 47 巻 4 号 p. 1254-1259
We measured the muscle torque of active knee motion for 50 knees in 42 cases who underwent total knee arthroplasty at the Yamaguchi Rousai Hospital, In this study, we used CYBEX 6000 and measured the muscle torque prior to operation, and 3 months, 6 months, 1 year, and 2 years after operation. The recovery of the extension and flexion torque of the knee began soon after the operation, and 3 months later their average torque was already superior to the one before operation. The recovery of the torque continued until 2 years after operation and their average torque was nearly equal to that of the controls. We found three factors which influenced the recovery of the torque, namely preoperative torque, the difference in diseases, suffered, and surgical method. Cases showing better preoperative torque tended to have a better postoperative torque, while casessuffering from rheumatoid arthritis showed better torque recovery than osteoarthritis copses within 3 months after operations. In cases on which the subvastus approach was performed, the postoperative torque tended to recover earlier than those by the medial parapatellar approach.