Surgical closing in primary total knee arthroplasties: flexion versus extension

One hundred eight consecutive patients with primary osteoarthritis of the knee undergoing primary arthroplasty were compared retrospectively to determine whether surgical closure of the entire wound in flexion has any effect on range of motion postoperatively over a period of up to 6 months. The knees of the first 52 patients were surgically closed in extension. In the second group of 56 patients, the knees were closed in 90 degrees to 110 degrees flexion depending on the available motion of the joint. Although the patients were not randomized, the groups were closely matched in age, weight, height, and gender. Preoperative and postoperative patellar heights were similar in both groups. The patients were started on a continuous passive motion device in the recovery room. At all intervals the flexion measurements were significantly better in the flexion closure group. By 6 months the flexion closure group had surpassed their preoperative measurements, whereas the extension closure group had not yet achieved this goal. The flexion group required less home physical therapy than the extension group. Closing the knee in flexion permits the patients to regain knee motion faster with less effort, thereby saving money and enhancing patient satisfaction.