More than 700,000 total knee arthroplasty (TKA) surgeries are performed annually in the United States, with projections of 3.5 million performed annually by 2030. While recent advances have led to improved TKA rehabilitation, the persistence of atypical movement patterns after unilateral TKA-characterized by surgical knee disuse-remains a major problem. Importantly, these atypical movement patterns are associated with persistent quadriceps weakness and poor physical function. In addition, atypical movement patterns create compensatory increased loading on the contralateral knee, which may be linked to progression of contralateral knee osteoarthritis. Application of new motor learning strategies to directly remediate atypical movement patterns can advance current rehabilitation by addressing persistent strength impairments and functional limitations and strength impairments after unilateral TKA. Therefore, the overall aim of this investigation is to perform a randomized controlled trial to determine if the addition of a novel movement pattern training program (MOVE) to contemporary rehabilitation after TKA improves movement pattern quality and functional outcomes compared to contemporary rehabilitation alone (CONTROL). Both the MOVE and CONTROL programs will include progressive, contemporary interventions focused on progressive intensive strengthening and functional training. In addition, the MOVE study-specific intervention targets motor movement pattern training of surgical knee use during common functional activities (e.g., walking and sit-to-stand) by utilizing innovative motor learning feedback methods. The CONTROL study-specific intervention focuses on traditional joint motion exercise and modalities in place of the movement training. Both the MOVE and CONTROL programs will be 6-week interventions delivered in an outpatient physical therapy clinic. Outcome testing will be performed before TKA surgery (baseline), and 2 months, 6 months, and 2 years after TKA. The primary outcome will be change from baseline to 6 months following TKA in peak external knee flexion moment at the surgical knee extension moment.. Peak external knee extension/flexion moment will be calculated with 3-dimensional instrumented motion analysis while participants perform walking (primary activity), as well as rising from a chair and stair stepping. We will also determine whether MOVE improves performance-based and self-report measures of physical function. We expect the MOVE program will result in substantial improvements in surgical knee extension peak external flexion moments compared to the CONTROL program, and that these improvements will be associated with improved physical function. As an exploratory aim, we will identify the relationship between atypical movement patterns and 2-year progression of contralateral knee OA.
A large increase in total knee arthroplasty surgeries is anticipated in the next two decades, yet innovative rehabilitation techniques are still needed to optimize long-term physical function. This study has high potential to change current rehabilitation practice for TKA because movement pattern training can be easily implemented in clinical settings. Furthermore, the study also has the unique opportunity to improve patient outcomes after TKA by reducing subsequent problems due to compensatory overuse of the opposite knee.
