Changes in pain and physical function during waiting time and 3 months after knee joint arthroplasty.

Abstract

OBJECTIVE: To determine changes in physical and social function during a prolonged preoperative waiting period and at 3 months after total knee arthroplasty. SUBJECTS: Forty-three patients were evaluated on the day that surgery was decided, the day before surgery, and 3 months afterwards. METHODS: Knee pain and function were assessed using a visual analogue scale and a functional assessment system. Isometric knee flexion extension strength and mobility were measured. RESULTS: Knee pain and muscle strength remained unchanged during the mean waiting time of 10 (standard deviation 8) months. On the affected side, knee extension strength was 19% weaker than on the contralateral side and did not change pre-operatively. Post-operatively, knee pain decreased by 50%. Knee extension strength decreased by 26% and flexion strength by 12% compared with the initial assessments. Knee extension strength of the operated side was 42% lower than on the non-operated side. Knee flexion mobility was decreased by 8%, while the initially detected knee extension deficit of 10 degrees (SD 7) remained unchanged. The functional assessment system did not detect any changes in function. CONCLUSION: Waiting time did not affect knee pain or isometric knee extension/flexion strength. Three months post-operatively, knee pain had decreased significantly, but the strength of the operated knee was significantly lower than the pre-operative level.