Effects of knee extension exercise starting within 4 h after total knee arthroplasty

Purpose To determine the beneficial effects of knee extension exercise applied from 4 h after TKA. Methods Patients undergoing TKA for osteoarthritis were assigned to early rehabilitation ( n = 41) and control rehabilitation ( n = 39) groups. Rehabilitation of knee extension exercise was started within 4 h postoperative in the early group and 2 days after surgery in the control group. Joint range of motion and pain were assessed before surgery and at 3 days to 12 months after surgery. Muscle strength and gait parameters were assessed before and 3 weeks after surgery. Results Extension range of motion was significantly increased in the early group than the control at 3 days, 3 weeks and 6 months after surgery. In gait parameters, peak knee flexion and extension angles during stance phase were significantly improved in the early group than the control group at 3 weeks after surgery. Flexion range of motion was increased in the early group than the control at 12 months after surgery. Conclusion Starting knee extension exercise within 4 h after TKA reduced the early loss of extension range of motion and improved gait pattern and seemed to contribute to be better functional outcome one year after surgery.