Effect of footwear on the external knee adduction moment - A systematic review

Context: Footwear modifications have been investigated as conservative interventions to decrease peak external knee adduction moment (EKAM) and pain associated with knee osteoarthritis (OA). Objective: To evaluate the literature on the effect of different footwear and orthotics on the peak EKAM during walking and/or running. Methods: A systematic search of databases resulted in 348 articles of which 33 studies were included. Results: Seventeen studies included healthy individuals and 19 studies included subjects with medial knee OA. Quality assessment (modified Downs and Black quality index) showed an (average +/- SD) of 73.1 +/- 10.1%. The most commonly used orthotic was the lateral wedge, with three studies on the medial wedge. Lateral wedging was associated with decreased peak EKAM in healthy participants and participants with medial knee OA while there is evidence for increased peak EKAM with the use of medial wedges. Modern footwear (subjects' own shoe, "stability" and "mobility" shoes, clogs) were likely to increase the EKAM compared to barefoot walking in individuals with medial knee OA. Walking in innovative shoes ("variable stiffness") decreased the EKAM compared to control shoes. Similarly, shoes with higher heels, sneakers and dress shoes increased EKAM in healthy individuals compared to barefoot walking. Conclusions: Further development may be needed toward optimal footwear for patients with medial knee OA with the aim of obtaining similar knee moments to barefoot walking. (C) 2011 Elsevier B.V. All rights reserved.