Evaluation of proximal joint kinematics and muscle strength following ACL reconstruction surgery in female athletes

Despite the intense focus on outcomes following an anterior cruciate ligament (ACL) reconstruction, it is not yet known whether unresolved abnormal hip and trunk neuromuscular control exists. The purpose of this study was to compare trunk and hip kinematics during running, hip abductor and external rotator strength, and trunk control between females who had undergone an ACL reconstruction and healthy control participants. We compared 20 ACL reconstructed females to 20 healthy individuals, measuring abduction and external rotation strength, a trunk control test, and performed an instrumented gait evaluation during running. Comparisons between groups were made for non-sagittal peak hip angles, forward trunk lean, trunk ipsilateral lean at initial contact, trunk control and hip abduction, and external rotation strength. We found no significant differences in hip abduction (p=0.25), hip external rotation strength (p=0.63), peak hip adduction (p=0.11) or hip internal rotation angle (p=0.47). The ACL group did have a significantly greater ipsilateral trunk lean (p=0.028), forward lean (p=0.004), and had higher errors on the trunk stability test (p=0.007). We found significant differences in trunk control, suggesting further attention should be devoted to this component of rehabilitation.