Toward personalizing prosthesis prescription: A take-home study of three microprocessor-controlled prosthetic knees: A randomized crossover study.

Abstract

Previous studies on microprocessor-controlled prosthetic knees (MPKs) often investigate benefits of MPKs as a class of knees rather than clinically relevant differences between specific knees, despite their distinct features. To systematically evaluate and report outcomes associated with three commercially available MPKs following a standardized real-world use period. Randomized crossover study. Research laboratory and community environment. Ten patients with transfemoral amputation. Three MPKs were fitted, trained, and worn for a 1-week period including C-Leg 4.0 (Ottobock, Duderstadt, Germany), Rheo Knee-Model RM7 (Össur, Reykjavik, Iceland), and Power Knee-PKA01 (Össur, Reykjavik, Iceland). Primary outcomes were the 10-meter walk test (10-mwt), the 2-minute walk test (2-mwt), and the Prosthesis Evaluation Questionnaire (PEQ). Secondary outcomes were stance time asymmetry, physiological cost index, stair and ramp speeds, the narrowing beam walking test, and community ambulation monitoring. Participants walked 11% faster in Rheo than Power Knee during the 10-mwt (95% confidence interval [CI]: 0.046-0.184, p = .015). In the 2-mwt, participants walked 12% faster in C-Leg (95% CI: 0.034-0.241, p = .003) and 9% faster in Rheo (95% CI: 0.031, 0.163, p = .027) than in Power Knee. On the PEQ, participants reported greater satisfaction with C-Leg compared to Power Knee (p = .006). Ramp ascent speed was 8% faster in Rheo than Power Knee (95% CI: 0.026-0.130, p = .024). No significant differences were found for other secondary outcomes. Notably, 10 of 12 outcomes showed individuals performing their best by a defined difference on an MPK different from the cohort's best-performing MPK. Participants walked faster in C-Leg and Rheo than Power Knee and reported greater satisfaction with C-Leg. Consideration of patient needs and characteristics may allow more individualized MPK prescription and thereby improve rehabilitation outcomes. NCT06399471.