Effects of shoes to reduce knee varus instability on walking in patients with knee osteoarthritis

Abstract

We developed shoes with a structure reducing varus instability of the knee (knee varus instability reducing shoes), and evaluated their effects on walking in patients with knee osteoarthritis. The subjects consisted of 21 patients with knee osteoarthritis (all female, aged 77.4±6.4 years). The values of walking parameters were compared between the knee varus instability-reducing shoes and general shoes. Walking using the knee varus instability-reducing shoes resulted in a significant decrease in the foot angle (p<0.001) and significant increases in the stride length (p<0.001), step length (p<0.001), and walking speed (p<0.001). However, no significant difference was observed in the step width, walking angle, stance time, or double support time between the two types of shoe. The effect sizes of the foot angle, stride length, step length, and walking speed showing significant differences were in the range of Δ= ­0.34­0.47. These results suggest certain effects of knee varus instability-reducing shoes on walking in patients with osteoarthritis.