Biomechanical analysis of rehabilitation in the standing position

Biomechanical analysis of the two-dimensional models composed from roentgenographic pictures and electro myographic analysis of the shear force exerted on the tibia during standing on both legs were conducted in 21 young adult males. The simultaneous contraction of the quadriceps and hamstrings was observed in all electromyograms. Amplitude observed on electromy ograms of the hamstrings increased as the trunk flexion angle increased. The calculated average values of shear force were negative at every knee flexion angle (nega tive value means posteriorly directed force). As the trunk flexion angle increased, posterior drawer force increased at knee flexion angles of 30° and 60°. The simultaneous contraction of the quadriceps and the hamstrings was considered to be the main factor that influenced these results. Standing on both legs with knee and trunk flexion was considered to be applicable in the early stages after anterior cruciate ligament re construction.