Manual therapy improves pain and walking function in geriatric knee osteoarthritis via proprioceptive mediation

Objective To evaluate the therapeutic effects of manual therapy (MT) on pain, walking function, proprioception, and lower-limb muscle strength in geriatric patients with knee osteoarthritis (KOA), and to explore potential biomechanical mechanisms. Methods In this prospective non-randomized controlled trial, 25 geriatric participants with unilateral mild-to-moderate KOA (intervention group) and 25 matched healthy controls were enrolled. The intervention group underwent a 4-week MT, while the control group received no intervention. The primary outcome was change in Western Ontario and McMaster Universities osteoarthritis index (WOMAC) pain subscale score. Secondary outcomes included 6-minute walk test (6-MWT) distance, proprioceptive force sense (PFS), and maximal isometric lower-limb strength. Causal mediation analysis was employed to investigate mechanistic pathways linking pain modulation to functional recovery. Results Following MT intervention, the intervention group demonstrated significant reductions in WOMAC pain scores (13.04 ± 4.39 vs. 5.36 ± 2.40; P < 0.001), increased 6-MWT distance [320.44 m [95% CI: 283.68–357.20] vs. 612.28 m [95% CI: 594.42–630.14]; P < 0.001], and diminished inter limb asymmetry in PFS (54.52 ± 19.35 N vs. 15.92 ± 11.00 N; P < 0.05). Mediation analysis revealed that restoration of proprioceptive sensitivity accounted for 69.59% of the total effect through which pain reduction enhanced ambulatory capacity. Muscle strength profiling further indicated that functional improvement was potentially mediated by neuromuscular rebalancing of bilateral agonist-antagonist coordination. Conclusion MT delivers significant short-term clinical benefits for elderly patients with unilateral mild-to-moderate KOA (Kellgren-Lawrence grades 0–2), including effective pain relief and improved walking ability, potentially through restoring proprioceptive sensitivity and modulating intermuscular balance.