Fig. 6

STS movements. a Normal STS movement. Doorenbosch et al. [16] reported that the hip joint angle at seat-off is 93.4 ± 8.4°. Thus, the STS movement when the hip flexion angle at seat-off is closest to 93° is regarded as a normal STS movement (black solid line). b, c STS movement when the hip joint contact forces are minimum (blue solid line) and maximum (red solid line), respectively