Postures adopted when using a two-wheeled cylinder trolley.

Upper limb and trunk positions were investigated when subjects exerted force to start and move a two-wheeled cylinder trolley with four different handles. Three of the handles had orientations 35 degrees, 50 degrees and 70 degrees in the sagittal plane (relative to the back of the trolley). The fourth was the 50 degrees handles fitted with a link bar. Measurements were made of x (horizontal), y (lateral) and z (vertical) coordinates of the body joints in space throughout the motion, using a CODA MPX30 optical 3-D measurement system, and both linear and angular displacements were computed. The linear and angular positions of the body joints were found to change through the stages of the task. Orientation of the handle influenced the arm postures adopted in the task, and showed to produce different patterns of arm displacement in force exertion to tilt the trolley from standing position. For steady movement, the sagittal plane 50 degrees handle proved most desirable.