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.