Implementation of Neuromuscular Electrical Stimulation After Total Knee Arthroplasty

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. This leads to muscle atrophy and likely contributes to the long-term weakness and disability patients with TKA experience relative to their healthy peers. Attenuating quadriceps strength loss should be a primary target for improving rehabilitation outcomes after TKA.

Neuromuscular electrical stimulation (NMES) is recommended in 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 preliminary data suggests that less than 4% of rehabilitation clinicians are using NMES as recommended by current TKA practice guidelines.

To address this gap, the investigators will conduct a cluster randomized trial in two healthcare systems (UCHealth and Intermountain Health) and their associated outpatient physical therapy clinics (n=30) to evaluate the effectiveness and implementation of NMES to address musculoskeletal deficits after TKA.

The investigators 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; Aim 1). The investigators will gather information on NMES implementation to promote its uptake and translation to clinical practice (Aim 2).

Inclusion criteria

Site Inclusion Criteria:

• UCHealth or Intermountain Health outpatient physical therapy clinic

Patient Inclusion Criteria:

• Underwent primary unilateral TKA
• Attended outpatient rehabilitation at a participating clinic within 5 days after TKA
• Attended at least 3 total outpatient physical therapy visits in total

Exclusion criteria

Patient Exclusion Criteria:

• NMES Contraindications [Patients with implanted cardiovascular cardiovertedefibrillator (ICD), active cancer, post-operative diagnosed deep vein thrombosis (DVT) in involved lower extremity]
• Previous lower extremity arthroplasty less than 12 weeks prior to scheduled TKA surgical date