抄録
Objective: Midvastus approach has been popular because of its potential to preserve the extensor mechanism function of the knee in patients undergoing total knee arthroplasty (TKA) . Short-term results of TKA using the midvastus approach are examined in this report.
Methods: Twenty-four patients (6 males and 18 females) underwent primary TKA using the midvastus approach; the average age of the patients was 70.4 years. Of these 24 patients, 8 had osteoarthritis, 14 had rheumatoid arthritis, and 2 had adult-onset Still's disease. The implants included Nexgen LPS Flex in 15 patients, CR Flex in 5, and Vanguard PS in 4. All operations were performed using an instrument specially designed for minimally invasive TKA. We examined femorotibial angle, incision length, period before the first day of straight leg raising (SLR), period before the first day of walker gait, range of motion, Japanese Orthopedic Association (JOA) score, operative time, and complications.
Results: Mean f emorotibial angle changed from 183.4° to 174.4°. The mean incision length was 11.5 cm. The mean period before the first day of SLR was 0.9 day. The mean period before the first day of walker gait was 1.8 days. With regard to the range of motion, mean extension changed from -12.0° to -2.8° and flexion improved from 125.4° to 130.5°. The mean JOA score increased from 44.8 to 83.0. The mean operative time was 161 min. Complications included intraoperative avulsion frac-ture of the lateral collateral ligament attachment of the femur in one patient and skin necrosis in one patient with skin atrophy after a prolonged use of steroids.
Conclusion: The short-term results of primary TKA using the midvastus approach were good, and the patients had faster recovery of knee function.
