The effects of small and large varus alignment of the foot-ankle complex on lower limb kinematics and kinetics during walking: A cross-sectional study.

Only 28 participants were analyzed, and the study was designed to detect large differences, so smaller differences could have been missed. The participants were healthy young adults without recent pain, surgery, or foot orthoses, so the results may not apply to patients with musculoskeletal problems. The study compared people who already had small or large alignment; it did not change alignment, so it cannot show that varus alignment caused the walking differences. When participants with large toe-out angle were not excluded, the large-varus and small-varus groups showed no differences. Toe-out can confound the relationship. Walking was tested on a treadmill, which may differ from overground walking. Muscle activity was not measured, so the source of the increased ankle inversion moment cannot be identified.

Do not conclude that foot varus alignment causes knee or hip problems, or that treating varus will change knee or hip mechanics. This study compared existing alignment groups in healthy young adults and found no differences in knee or hip variables during treadmill walking.