Feasibility and Biomechanical Effects of Dynamic Neuromuscular Stabilization Training During Stair Negotiation in Middle-Aged Women with Knee Osteoarthritis: A Randomized Controlled Pilot Study

Background: Knee osteoarthritis (KOA) alters the performance of daily activities, such as stair negotiation, by compromising lateral stability and neuromuscular control. This pilot study aimed to evaluate the feasibility of a 10-week Dynamic Neuromuscular Stabilization (DNS) program and to explore its preliminary biomechanical effects during stair ascent and descent in middle-aged women with KOA. Methods: Twenty-six participants were randomly assigned to a DNS group (n = 13) or a control group (n = 13). The DNS group completed a 10-week intervention (twice weekly). Feasibility was assessed via recruitment, retention, and adherence. Primary outcomes were mediolateral (ML) center of pressure (COP) parameters, while secondary outcomes included anteroposterior (AP) COP parameters and lower limb range of motion (ROM). Effect sizes (η2p) were estimated using 3D motion analysis and force plates. Results: The intervention showed high potential feasibility, with 100% recruitment and retention rates and 98.5% compliance. No adverse events occurred. Large effect sizes were observed for reduced ML COP velocity (ascent: η2p = 0.79; descent: η2p = 0.62) and RMS (descent: η2p =0.16). Secondary outcomes, including AP COP parameters and joint ROM (increased sagittal flexion and decreased coronal instability), also demonstrated large effect sizes. Conclusions: This pilot study suggests that progressive DNS training appears to be feasible and safe for patients with KOA. The preliminary effect sizes observed in COP control and lower kinetic chain mechanics may serve as useful foundational data for designing future adequately powered clinical trials to further examine the efficacy and underlying biomechanical mechanisms of DNS training.