REDUCTION IN THE KNEE ADDUCTION MOMENT DURING WALKING USING LATERALLY-WEDGED SHOES WITH AND WITHOUT ANKLE SUPPORT

摘要

A high maximum adduction moment at the knee during walking has been associated with an increased rate of progression [1] and worse treatment outcome [2] of medial compartment osteoarthritis (OA) of the knee. Laterally-wedged insoles and shoes have been shown to reduce the knee adduction moment in healthy and osteoarthritic populations [3,4]. However, the mechanism of the effectiveness of such interventions is not well understood. Toda et al. showed that subtalar strapping with laterally wedged insoles in osteoarthritic subjects can improve valgus correction, but the authors did not look at the dynamic effects of walking [5]. A second study looked at the effects of lateral wedges with both semi-rigid ankle support and a rigid ankle-foot-orthosis and found a reduction in the adduction moment only with ankle support and a 10° lateral wedge. The wedge alone did not produce a reduction in the adduction moment [6]. Thus, it seems that the mechanism of action of the lateral wedge may be influenced by ankle motion. The overall goal of this study was to gain a better understanding of the mechanism of reduction in the knee adduction moment and its relation to motion at the ankle joint. We hypothesized that the knee adduction moment will be reduced (1) with the use of a 4° laterally-wedged shoe, and (2) the reduction in adduction moment at the knee will be greater with the addition of a semi-rigid ankle brace in conjunction with the laterally-wedged shoe. We also examined frontal plane moments at the ankle to assess changes with the addition of a semi-rigid ankle brace.