Pain and recovery of physical functioning nine months after total knee arthroplasty.

OBJECTIVE To describe pain and recovery of physical functioning after total knee arthroplasty. DESIGN A longitudinal design with assessments preoperatively, and 1 week, 3 and 9 months postoperatively. SUBJECTS Sixty-three patients participated. METHODS Pain was assessed by visual analogue scale. Physical functioning was measured by 40-metre timed walking, timed stair-climbing and goniometry. At 9 months the Short Form-36 pain and physical function scales were added to make comparisons with the general population. RESULTS Pain score one week after surgery was 40 (standard deviation (SD) 23) vs 24 (SD 19) at 3 months (p < 0.001). At 9 months the pain score was 22 (SD 23) vs 49 (SD 18) preoperatively (p < 0.001). Knee extension did not differ from preoperative scores, but knee flexion reduced from 124 (SD 13) to 112 (SD 12) (p < 0.001). Forty-metre walking time improved from 37 (SD 13) to 34 (SD 11) s (p < 0.001), while the number of patients able to climb stairs was unchanged (p > 0.05). The patients' Short-Form 36 pain score did not differ from the general population, while the physical function score was 60 (SD 24) vs 75 (SD 24) (p < 0.001). CONCLUSION Early pain reduction was registered. At 9 months, pain was equal to that in the general population, but a considerable number of patients still had problems in performing strenuous activities.