Objective: To examine and compare the gait patterns of subjects with hamstring and patellar tendon graft reconstructions of anterior cruciate ligament (ACL).
Methods: Three groups were compared: 19 patellar tendon anterior cruciate ligament reconstruction patients (a mean of 11.8 weeks after injury), 19 hamstring tendon anterior cruciate ligament reconstruction patients (a mean of 10.4 weeks after injury) and 19 matched controls. Gait analysis was performed using the DorealSoft DVMC-8801 three-dimensional motion capture system. Kinematic data were recorded for the lower limb prior to and 3, 6, 9 and 12 months after ACL reconstructive surgery. Each subject was asked to walk on a motorized treadmill with different slopes and perform-after 6 minutes of familiarization time- at least 2 minutes of walking at a constant speed of 1.9 km/h.
Results: All the ACL-deficient patients exhibited a quadriceps avoidance pattern prior to and 3 months post-operation. In the operated individuals, the spatial-temporal parameters and the knee angle had already regained a normal pattern for the ACL-deficient limb during gait at 6 months post-operation. However, the angular acceleration showed no significant statistical difference with the values of healthy control group at just 9 months post-operation. The flexion angular acceleration at 15 degrees treadmill was significantly smaller than that in the hamstring tendon group and the extension angular acceleration was significantly smaller than that in the patellar tendon group at 6 months post-operation.
Conclusion: ACL surgical repair significantly alters the lower-extremity gait patterns and the establishment of pre-injury gait patterns takes at least 9 months to occur. The graft-specific differences in knee biomechanics after anterior cruciate ligament reconstruction appear to be related with the donor site.