Preoperative physical factors that predict stair-climbing ability at one month after total knee arthroplasty

Abstract

Objective: To identify preoperative physical performance factors that predict stair-climbing ability at one month after total knee arthroplasty. Design: Prospective cohort study. Setting: University-based rehabilitation centre. Subjects: Eighty-four patients who underwent a primary unilateral total knee arthroplasty. Methods: Before and one month post-operation, the patients completed physical performance tests, including a stair-climbing test, a 6-minute walk test, a Timed Up-and-Go test, tests of the isometric flexor and extensor strength of the operated and non-operated knees, and instrumental gait analysis. Disease-specific physical function was measured by the Western Ontario McMaster Universities Osteoarthritis Index. Results: Correlation analysis showed that postoperative stair-climbing test scores were significantly correlated with preoperative physical performance and function. Linear regression analysis showed that postoperative stair-ascent scores were correlated with preoperative Timed Up-and-Go test scores and peak torque of the extensor of the operated knee. Postoperative stair-descent scores were positively correlated with preoperative stair-descent scores and age. Conclusion: The results show that preoperative balance ability and quadriceps strength in the operated knee could influence postoperative stair-climbing ability at one month after total knee arthroplasty. These findings will be useful for developing pre- and post-operative rehabilitation strategies for improving stair-climbing ability in the early stages after total knee arthroplasty.