Alterations in joint kinematics during walking following hamstring and patellar tendon anterior cruciate ligament reconstruction surgery

BackgroundPrevious research has shown that patients with anterior cruciate ligament reconstruction have altered movement patterns in the reconstructed knee during walking. In the sagittal plane, graft specific changes in knee joint motion have been reported between hamstring and patellar tendon anterior cruciate ligament reconstruction grafts. This study examined the secondary planes of movement during walking in anterior cruciate ligament reconstructed knees to evaluate the influences of graft type (hamstring or patellar tendon) and control condition (control group or contralateral knee).MethodsIn 54 participants (18 patellar tendon graft, 18 hamstring graft and 18 controls) varus–valgus and internal–external rotation was measured during level walking in a gait laboratory at mean of 10 months after surgery. All patients had undergone primary unilateral anterior cruciate ligament reconstruction within 12 months of injury.FindingsFor internal–external rotation there was no difference between the graft types and both patient groups had reduced internal rotation (an external rotation offset) and reduced internal rotation range when compared to the control group and contralateral knee. For 31 of 36 patients, internal rotation values were less than the control group mean. The hamstring group had reduced varus rotation compared to both the patellar tendon and control groups, but not when compared to the contralateral knee.InterpretationThe results show that there are differences in tibial rotation during walking in anterior cruciate ligament reconstructed knees compared to both the contralateral knee and uninjured control group. These kinematic alterations may relate to the high incidence of knee osteoarthritis observed in this population over time. Reduced varus in the hamstring group may relate to the graft harvest.