Association of physical performance with muscle strength and hip range of motion in hip osteoarthritis

Abstract

Objective. To examine whether the associations of physical performance with isometric hip and knee extensors strength and passive hip flexion and internal rotation range of motion (ROM) are nonlinear in community-dwelling adults with hip osteoarthritis (OA). Methods. Participants were 100 adults (mean age 62 years) with radiographically confirmed hip OA. Physical performance measures included gait speed test and timed stair tests. Piecewise regression models of muscle strength and hip ROM on physical performance measures were used to identify possible breakpoints. Receiver operating characteristic (ROC) curve analysis was used to identify participants with functionally inadequate (≥1.0 meter..