Longitudinal Gait Adaptations of ACL-Injured Individuals Reconstructed with the Hamstring Graft
M.R. Torry , J. Wilson, M.J. Decker, H.B. Ellis, F.Q. Pecha, W.I. Sterett, J.R. Steadman; Steadman Philippon Research Institute, Vail, CO
Longitudinal gait adaptations of ACL-injured patients reconstructed with the patellar tendon have been described. Gait adaptations that may occur in individuals after semitendinosus-gracilis graft (DLSTG) reconstruction have not been identified despite its wide spread use. The purpose of this study was to compare the joint kinematics and kinetics during walking at 3, 6, 9 and 12 weeks post-surgery in patients reconstructed with the DLSTG technique to a healthy group. Nine DLSTG patients and five healthy subjects walked at self-selected and 1.5 m/s, respectively. Video (60 Hz) and force platform (1200 Hz) data were collected and combined with anthropometrics in an inverse dynamics solution to compute hip and knee joint kinematic and kinetic data. Individual t-tests (p = 0.05) were used to determine gait differences between the reconstructed group and the control group at each session.
|Variable||3 wks||6 wks||9 wks||12 wks||Group|
|Stance time (%)||64.56*||62.22*||60.00||59.98||58.90|
|Ave. hip position (deg)||7.83||7.07||3.78||2.79||2.59|
|Ave. knee position (deg)||30.25*||24.87*||22.29*||19.31||17.69|
|Knee ext. impulse||9.04*||10.24*||5.65||5.47||4.62|
|Hip ext. impulse||11.71*||10.82||10.44||9.96||9.69|
Compared to normals, early (0-6 wks) adaptations in the DLSTG group were characterized by slower walking velocity, increased stance time, increased hip and knee flexion and extensor angular impulses. Except for average knee position, all gait parameters returned to near normal values at 9 weeks post-reconstruction.