Gender differences in knee kinematics during weight-bearing knee flexion for patients with arthrofibrosis after anterior cruciate ligament reconstruction

BACKGROUND: Knowledge of tibiofemoral and patellofemoral joint kinematics is important for understanding gender-related dimorphism in developing knee arthrofibrosis and advancement of related treatments. The objective of our study was to investigate gender differences existing in tibiofemoral kinematics and patellar tracking in patients with arthrofibrosis after anterior cruciate ligament (ACL) reconstruction during weight-bearing knee flexion. METHODS: The tibiofemoral and patellofemoral joint kinematics were measured in 30 patients (15 male and 15 female) with arthrofibrosis after ACL reconstruction during a lunge task, using computed tomography and dual fluoroscopic imaging system. These data were analyzed for gender differences. RESULTS: The range of tibial rotation, patellar inferior shift, tilt, and flexion were significantly decreased in the affected knee compared to the contralateral knee from 15° to 75° of knee flexion (P ≤ 0.04). Statistically significant difference was detected for medial tibial translation between male and female patients at 60° (P = 0.04) and 75° of knee flexion (P = 0.02). The tibial rotation was significantly decreased at 60° (P = 0.03) and 75° of knee flexion (P < 0.01) in females. The inferior patellar shift in females was significantly lower than that in males at 15° (P = 0.04) and 30° of knee flexion (P = 0.01). The patellar tilt was significantly lower at 60° (P = 0.02) and 75° of knee flexion (P < 0.01) in females compared to males. CONCLUSIONS: The results indicated a significant effect of gender on knee kinematics in patients with arthrofibrosis after ACL reconstruction during weight-bearing knee flexion. These gender differences in tibiofemoral kinematics and patellar tracking may warrant further investigations to determine implications for making gender-specific surgical treatments and rehabilitation programs.