A biomechanical study of activities of daily living using neck and upper limbs with an optical three-dimensional motion analysis system.

In activities of daily living such as eating meals, the neck and upper limbs move in coordination. However, no methods have been established to analytically and quantitatively capture motion of the neck and limbs during these activities. We used a Vicon 512 system to simultaneously measure ranges of motion (ROMs) for the cervical spine, shoulders, elbows, and forearms. Correlations between the motion analyzer and the universal goniometer were >0.76. Repeatability of measurements using this analyzer were <or=3 degrees for all values. This system is thus highly accurate and can be useful for motion analysis of the neck and upper limbs. The sum of flexion angles for the cervical spine, shoulders and elbows were almost constant for each activity, at 261 degrees for shampooing, 207 degrees for washing the face, and 185 degrees for eating a meal.