Sex-Specific Gait Adaptations Prior to and up to 6 Months After Anterior Cruciate Ligament Reconstruction

STUDY DESIGN: Controlled longitudinal laboratory study. OBJECTIVES: To compare sagittal plane gait mechanics of men and women before and up to 6 months after anterior cruciate ligament reconstruction (ACLR). BACKGROUND: Aberrant gait patterns are ubiquitous after anterior cruciate ligament (ACL) rupture and persist after ACLR despite skilled physical therapy. Sex influences postoperative function and second ACL injury risk, but its influence on gait adaptations after injury has not been investigated. METHODS: Sagittal plane knee and hip joint excursions during midstance and internal knee and hip extension moments at peak knee flexion were collected in 12 women and 27 men using 3-D gait analysis before (screening) and after preoperative physical therapy (presurgery), and 6 months after ACLR (6 months postsurgery). Repeated-measures analysis-of-variance models were used to determine whether limb asymmetries changed differently over time in men and women. RESULTS: Significant time-by-limb-by-sex interactions were identified for hip and knee excursions and internal knee extension moments (P <=.007). Both sexes demonstrated smaller knee excursions on the involved limb compared to the uninvolved limb at each time point (P <=.007), but only women demonstrated a decrease in the involved knee excursion from presurgery to 6 months postsurgery (P = .03). Women also demonstrated smaller hip excursions (P<.001) and internal knee extension moments (P = .005) on the involved limb compared to the uninvolved limb at 6 months postsurgery. Men demonstrated smaller hip excursions and knee moments on the involved limb compared to the uninvolved-limb (P<.001) regardless of time. CONCLUSION: The persistence of limb asymmetries in men and women 6 months after ACLR indicates that current postoperative rehabilitation efforts are inadequate for some individuals following ACLR.