Hip Rotation as a Crucial Risk Factor for Anterior Cruciate Ligament Injury in Female Athletes

Abstract

Non-contact anterior cruciate ligament (ACL) injuries occurs with a higher incidence in female athletes compared with males after the onset of puberty. One anatomical factor with clinically observable differences between males and females is lower extremity alignment. The knee joint valgus in the coronal plane, which is associated with ACL injury risk, is composed of rotation of the tibia around the stationary femur and hip rotation combined with knee flexion. However, knee abduction measurements require expensive biomechanical laboratories. Therefore, it is important to develop simple measurement methods of the anatomical and structural factors to determine female athletes at increased risk for ACL injury. PURPOSE: The purpose of this study was to prove the difference of hip rotation between female and male handball players with or without history of ACL injury. METHODS: Elite collegiate athletes on the varsity handball team (17 females and 24 males) were recruited. Whereas 8 females and 1 male had a history of ACL injury, there were 9 females and 23 males with no history of ACL injury. The 6 measures of hip joint motion (flexion, extension, abduction, adduction, external rotation, and internal rotation) and the 2 measures of knee joint motion (flexion and extension) were measured with the standard procedure using a goniometer. RESULTS:Table: No title available.*p<0.05 vs. female players with no ACL injury COCLUSION: Female handball players with a history of ACL injury had greater hip internal rotation with smaller hip external rotation, compared with the counterpart without history of ACL injury. Hip rotation, which can be readily measured by coaches, athletic trainers, physical therapists, and athletes, may be a crucial risk factor for ACL injury in female athletes.