Trunk and lower extremity kinematics during single leg drop landing in adult women with hyperextended knees

Abstract

Objective: A laboratory study was conducted to investigate the correlation between the knee extension-flexion angle in the static standing position, and the knee joint flexion angle immediately after initial contact and Peak vertical ground reaction force (Peak VGRF) during single leg landing. The characteristics of trunk and lower extremity biomechanics were analyzed in adult women with more than 10 degrees of knee extension (hyperextension group).

Methods: The participants were 21 adult women. A three-dimensional motion analyzer and a force plate were used to measure the knee extension-flexion angle in static standing and the trunk and lower limb kinematics at 40 ms after initial contact and Peak VGRF during single leg landing.

Result: No significant correlation was found between knee extension-flexion angle in static standing and knee joint flexion angle and Peak VGRF during single leg landing. The hyperextension group showed significantly lower trunk and hip flexion angles than the control group.

Conclusion: Landings with small trunk and hip flexion angles have been associated with non-contact ACL injuries, and should be addressed when preventing ACL injuries in hyperextended knee.