Comparing the effect of off-loading knee brace with and without local muscle vibration on clinical and biomechanical outcomes in patients with medial knee osteoarthritis: A randomized clinical trial

Background: Medial knee osteoarthritis (KOA) is a prevalent degenerative joint disease causing pain and functional impairment. Off-loading knee braces reduce pain but may decrease muscle activity, leading to weakness. Integrating local muscle vibration (LMV) into off-loading braces may enhance muscle activation and clinical outcomes. Objective: To design a portable LMV system synchronized with gait phases and compare its efficacy to a conventional off-loading brace in patients with medial KOA. Methods: In this randomized clinical trial, 16 patients with medial KOA were assigned to either an LMV-equipped off-loading brace group or a conventional brace group for 4 weeks. Clinical outcomes (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], Visual Analog Scale [VAS]) and biomechanical parameters (knee adduction moment [KAM1, KAM2], impulse, range of motion [ROM], cadence, stride length) were assessed pre- and post-intervention using validated questionnaires and a motion analysis system. Results: The LMV-equipped brace group demonstrated a significantly greater reduction in KAM impulse (-24.79% vs. -7.68%, p=0.050) and improved knee ROM (p=0.048) compared to the conventional brace group. Significant improvements in WOMAC (p=0.001) and VAS (p=0.011) scores were observed in the LMV group, indicating enhanced functional status and pain relief. Conclusion: The LMV-equipped off-loading brace provides superior biomechanical (KAM impulse, ROM) and clinical outcomes compared to conventional braces, offering a promising intervention for medial KOA.