Effect of lower limb dominance on knee joint kinematics after anterior cruciate ligament reconstruction.

ABSTRACT

BACKGROUND: Normal ambulatory kinematics of the knee joint is often not fully restored after anterior cruciate ligament reconstruction, which may increase the risk for cartilage degeneration and premature osteoarthritis in the involved knees. Lower limb dominance may have impacts on knee joint kinematics after anterior cruciate ligament reconstruction, which may lead to a different prevalence of cartilage degeneration. This study aimed to evaluate the knee joint kinematics among patients with reconstruction on the dominant and non-dominant side. METHODS: Forty-one subjects with unilateral anterior cruciate ligament reconstruction (19 dominant, 22 non-dominant) were recruited after being discharged from rehabilitation programs. Twenty healthy subjects were recruited as the control group. Six degrees-of-freedom tibiofemoral motion during level walking was determined using a redundant point cluster-based marker set. Tibiofemoral joint motion and its bilateral differences were compared within each group and between groups. FINDINGS: The non-dominant reconstructed knees had less extension compared to their contralateral knees at heel strike and during middle stance phase (P=0.02); whereas, the dominant reconstructed knees exhibited significantly reduced varus rotation (-2.1° on mean, P=0.027) and internal tibial rotation (P=0.034) compared to their contralateral knees during both stance and swing phases. INTERPRETATION: The results show that different kinematics has been developed between the involved dominant and non-dominant knees after anterior cruciate ligament reconstruction, especially the secondary rotations. The differences are consistent with the unequal prevalence of cartilage degeneration in the knee joint. The findings demonstrated that the lower limb dominance had a significant effect on post-surgery knee kinematics.