Upper limb kinetic analysis of three sitting pivot wheelchair transfer techniques.

BACKGROUND The objective of this study was to investigate differences in shoulder, elbow and hand kinetics while performing three different SPTs that varied in terms of hand and trunk positioning. METHODS Fourteen unimpaired individuals (8 male and 6 female) performed three variations of sitting pivot transfers in a random order from a wheelchair to a level tub bench. Two transfers involved a forward flexed trunk (head-hips technique) and the third with the trunk remaining upright. The two transfers involving a head hips technique were performed with two different leading hand initial positions. Motion analysis equipment recorded upper body movements and force sensors recorded hand reaction forces. Shoulder and elbow joint and hand kinetics were computed for the lift phase of the transfer. FINDINGS Transferring using either of the head hips techniques compared to the trunk upright style of transferring resulted in reduced superior forces at the shoulder (P<0.002), elbow (P<0.004) and hand (P<0.013). There was a significant increase in the medial forces in the leading elbow (P=0.049) for both head hip transfers and the trailing hand for the head hip technique with the arm further away from the body (P<0.028). The head hip techniques resulted in higher shoulder external rotation, flexion and extension moments compared to the trunk upright technique (P<0.021). INTERPRETATION Varying the hand placement and trunk positioning during transfers changes the load distribution across all upper limb joints. The results of this study may be useful for determining a technique that helps preserve upper limb function overtime.