Weakened Trunk Muscles Influence Knee Valgus Moments Associated with ACL Injury

Introduction: Over 200,000 anterior cruciate ligament (ACL) injuries occur every year in the United States alone [1, 2]. These injuries often occur in sports where dynamic movements, such as jump landings, place high loads on the ACL [3, 4]. Studies have shown increased knee valgus moments, small knee flexion angles, and anterior tibia translation contributes to ACL injury during landing [5-7]. While the role of trunk muscle strength in landing biomechanics is unknown, some studies have shown altered trunk position may increase knee valgus moments [8