Background Acute knee injuries and chronic knee pain are prevalent lower limb pathologies. These pathologies are often associated with abnormal lower limb biomechanics, reduced physical function and poor quality of life. Footwear has been advocated as an intervention for pathology affecting the knee due to its ability to alter lower limb biomechanics and loading at the knee joint. Footwear has been shown to influence lower limb biomechanics in healthy populations, however, it is unclear if these changes are seen in people with knee pathology. Therefore, the purpose of this study was to systematically review the current literature on the effects of footwear on lower limb biomechanics for people with knee pathology.

Methods A search of electronic databases was undertaken in August 2022. Studies were eligible for inclusion if they reported on biomechanical findings of the use of footwear for knee pathology. Key exclusion criteria were studies where footwear was used in combination with removable insoles or orthoses, or those not investigating lower limb biomechanics. The methodological quality of included studies was assessed using the National Heart Lung & Blood Institute Study Quality Assessment Tools. Data extracted from the included studies was reported in tables and summarised qualitatively.

Results 2,800 studies were identified for screening with 36 studies included for this review. Most studies investigated knee osteoarthritis (32), but also included were patellofemoral pain syndrome (2), anterior cruciate ligament injury (1) and meniscus injury. Footwear interventions included minimalist footwear (12), laterally wedged footwear (2), variable stiffness footwear (10), motion-control footwear (4), cushioned footwear (3), rocker-soled footwear (5) and other footwear (2). For people with knee osteoarthritis, minimalist footwear and variable stiffness footwear were associated with significant reductions in peak knee adduction moment compared to participant’s own footwear, other footwear and conventional footwear. Motion-control footwear was associated with lower medial tibiofemoral contact forces compared to minimalist footwear in people with knee osteoarthritis. For people with patellofemoral pain syndrome, minimalist footwear was associated with reduced patellofemoral joint stress and patellofemoral joint reaction forces compared to cushioned footwear. For people with anterior cruciate ligament injury, rocker-soled footwear was associated with increases in knee flexion. For people with meniscus injury, no differences in knee adduction moments were between laterally wedged, motion-control, cushioned and conventional footwear.

Conclusions This systematic review has identified diversity in footwear interventions used in individuals with knee pathology to reduce knee loading. The results have shown that this conservative strategy may help to offload the knee joint slow disease progression at the knee. Further research is required to determine the most effective footwear intervention for people with knee pathology.