Tibiofemoral rotation in landing: the influence of medially and laterally posted orthotics

Objective. To assess the relationship between foot alignment and transverse plane knee motion during a single leg-landing task. Design. Clinical trial. Setting. Hospital biomechanics laboratory. Participants. Seven healthy young women without excessive forefoot, arch, or rear-foot malalignments. Methods and measures. Varus and valgus foot malalignments were mimicked by placing 8° medial and lateral posted orthotics into the shoes before participants performed three landings from a drop jump off a 43 cm high platform. The change in tibiofemoral rotation relative to the no orthotic condition was measured. Results. The medial posted orthotic resulted in 3.1±5.5° less internal tibiofemoral rotation as compared to the nonorthotic condition, while the lateral posting produced 2.6±2.2° more internal tibiofemoral rotation ( t 6=−2.51, p≤0.03). Conclusions. Orthotic induced malalignments altered the magnitude of tibiofemoral rotation during a closed kinematic chain activity. Orthotic posting may be used to reduce the rotary stress on the knee during landing activities.