Implementation of Neuromuscular Electrical Stimulation after Total Knee Arthroplasty

PROJECT SUMMARY / ABSTRACT Total Knee Arthroplasty (TKA) reduces pain and disability caused by knee osteoarthritis, but the surgery results in substantial trauma to the knee. This acute trauma exacerbates underlying weakness— especially in the quadriceps. Quadriceps strength decreases by 80% just days after surgery and remains 60% impaired 1 month after surgery, which leads to a decrease in patient functional performance of up to 90%. This acute strength leads to muscle atrophy, which likely contributes to the long-term weakness and disability patients with TKA experience relative to their healthy peers. Therefore, attenuating quadriceps strength loss should be a primary target for improving rehabilitation outcomes after TKA. Neuromuscular electrical stimulation (NMES) is recommended in recent TKA clinical practice guidelines to attenuate quadriceps strength loss. In controlled settings, NMES has established efficacy and attenuates quadriceps strength loss by 40% in the first month after surgery by overriding muscle activation deficits and reducing muscle atrophy. However, the effectiveness of NMES after TKA has not been adequately studied in real-world clinical settings, and our preliminary data suggests that less than 4% of rehabilitation clinicians are using NMES as recommended by current TKA practice guidelines. Therefore, we propose to conduct a cluster randomized trial in two healthcare systems (Intermountain Health and UCHealth) and their associated outpatient physical therapy clinics (n=30) to evaluate the effectiveness and implementation of NMES to address musculoskeletal deficits after TKA. We will compare outcomes between patients who receive contemporary rehabilitation supported by a comprehensive NMES implementation strategy (NMES) to patients who receive contemporary musculoskeletal rehabilitation alone (Usual Care). We will gather information on NMES implementation to promote its uptake and translation to clinical practice. This study will fundamentally change rehabilitation practice to improve function, strength, and quality of life for millions of Americans who undergo TKA each year. This investigation seeks to provide large-scale, foundational evidence that NMES is effective and can be systematically implemented into TKA rehabilitation practice. It will also evaluate and identify effective implementation tools and strategies that healthcare organizations can readily adopt and deploy to promote widescale NMES usage after TKA.