Application of wearable neuromuscular electrical stimulation in home-based rehabilitation following total knee arthroplasty– a retrospective cohort comparison

To evaluate the short-term outcomes of home-based rehabilitation using wearable neuromuscular electrical stimulation (NMES) compared with conventional home rehabilitation with outpatient guidance following primary unilateral total knee arthroplasty (TKA). A retrospective propensity score–matched cohort analysis of patients who underwent primary unilateral TKA between November 2022 and November 2023. After propensity score matching (up to 1:2, caliper 0.2 on the logit of the propensity score), 60 NMES patients and 115 controls were included in the primary comparative analysis. The primary outcome was knee extensor strength at 12 weeks (kgf). Secondary outcomes included knee range of motion (°), Five-Times Sit-to-Stand (5xSST, s), single-leg stance (s), WOMAC, KSS, and SF-36. Multiplicity for efficacy outcomes was controlled using Bonferroni correction. At 12 weeks postoperatively, the NMES group showed significantly better results in knee extension strength(17.1 ± 3.7 vs. 15.0 ± 4.1 kgf, P = 0.020), ROM (127° ± 8.8 vs. 119 °± 5.5; MD = 8.0°; 95% CI, 5.5°–10.5°; P = 0.004), and five-times sit-to-stand test (15.3 ± 3.3 vs. 19.1 ± 3.6; MD = − 3.8 s; 95% CI, − 4.9 to − 2.7 s; P < 0.001). No significant differences were observed in WOMAC score, KSS score, complication rate, or 90-day readmission rate.Taken together, the between-group gains in ROM and 5xSST are clinically meaningful, exceeding commonly cited thresholds (ROM MCID 3.8–6.4°; 5xSST MDC = 1.8 s) for early post-TKA recovery. Home-based wearable NMES yielded clinically meaningful improvements in early ROM and functional performance (5xSST) after TKA versus standard home rehabilitation; effects on strength and balance were modest.