The purpose of this study was to investigate the sprinting motion of unilateral trans-femoral amputee sprinters to determine a direction for training. A unilateral trans-femoral amputee high level male sprinter (100 meter record : 12.73 s) was filmed while sprinting at maximal velocity. In addition, the ground reaction force and strain detected on a double clamp adapter connected to a socket in the knee joint of his prosthetic leg were recorded during the trial. Three-dimensional coordinate data were obtained by the DLT method. The kinematics and kinetics of the hip, knee and ankle joints were calculated from these data. The maximal sprint velocity was greater for the prosthetic leg (7.86 m/s) than for the normal leg (7.67 m/s). In the swing phase, hip joint torque was similar for both legs. For the hip joint in both legs, flexion torque was exerted during the first half of the phase, whereas extension torque was exerted during last half of the phase. On the other hand, the hip joint torque in each leg was different in the contact phase. For the prosthetic leg, extension torque was exerted throughout the contact phase. However, for the normal leg, the joint torque changed from extension torque to flexion torque during the contact phase. These results reveal that the motion of the normal and prosthetic legs was not symmetric. In addition, they suggest that the sprinter should be trained in a way based on consideration of the difference between the two legs.
View full abstract