Kinematic analysis of stand-to-sit motion in lumbar canal stenosis

Abstract

[Purpose] This study examined the kinematic characteristics of the stand-to-sit (STS) motion of patients with lumbar canal stenosis (LCS). [Subjects and Methods] The subjects were 24 patients with LCS and 18 age-matched asymptomatic controls. Kinematic data of STS motion was analyzed using video images collected by a digital video camera. [Results] In the downward phase, knee flexion movement of the LCS subjects was significantly smaller than that of the controls, and acceleration and deceleration of trunk and hip joint angles of the LCS subjects alternated more often. In the backward phase, shift of center of mass (COM) and posterior tilt angle of the pelvis of the LCS subjects were significantly larger than those of the controls, and acceleration and deceleration of knee joint angle of the LCS subjects alternated more often. [Conclusion] These findings suggest that LCS patients lack coordination of the trunk and lower limbs in the downward phase. In the backward phase, the magnitudes of the backward shift of COM and backward tilt of the pelvis were large, suggesting that the LCS subjects used a strategy requiring more knee extension power.