Comparative efficacy of foot orthoses stabilizing methods on pain intensity, balance performance, and knee adduction moment in medial knee osteoarthritis: A randomized trial of subtalar straps vs. high-top shoes

Abstract

Background and objective Medial knee osteoarthritis (MKOA) is a prevalent degenerative joint condition associated with pain and altered knee joint loading. This superiority randomized trial compared the effects of a lateral wedge foot orthosis stabilized with subtalar straps (LWSS) versus one stabilized with high-top shoes (LWHTS) on pain intensity and knee adduction moment in patients with MKOA. Methods Forty-four individuals with MKOA were randomly allocated (1:1) to LWSS or LWHTS. Primary outcomes were pain intensity (visual analogue scale, VAS) and balance performance (timed up and go test, TUG), assessed at 4-week follow-up. Secondary outcomes comprised knee adduction moment parameters (first peak, second peak, and angular impulse) and additional balance measures (timed stair climb, repeated chair rise, and single-leg stance). Between-group differences were examined using repeated-measures analysis of variance. Results At 4-week follow-up, LWHTS produced significantly greater pain reduction than LWSS (mean difference MD: 2.27 cm, 95% CI: 2.02 to 2.52, p < 0.001). For knee adduction moment, LWHTS significantly reduced first peak (MD: 0.16 Nm/BW & times;Ht, 95% CI: 0.14 to 0.18, p < 0.001) and angular impulse (MD: 1.92 Nm & centerdot;s/BW & times;Ht, 95% CI: 0.96 to 2.88, p < 0.001) compared with LWSS; no between-group difference was found for second peak (p = 0.99). No adverse events were reported in either group. Conclusion LWHTS provided superior pain relief and greater reduction in knee adduction moment compared with LWSS at 4 weeks in early-to-moderate MKOA, supporting high-top shoe stabilization as a more effective strategy for medial compartment unloading.