Dynamics of the upper limb during performance of the tasks of everyday living--a review of the current knowledge base.

This paper provides a brief review of the published literature on the subject of kinematics and kinetics of the human arm and shoulder mechanism, specifically when performing the tasks of everyday living. Surprisingly, only a small number of papers covering functional analysis of the arm were found, and the majority of these were concerned only with the kinematics of the elbow and lower arm. Differences in experimental method and a lack of consensus as to how to model the joint axes of the human arm make the results difficult to compare. Results are normally only presented in the form of angular excursion of the arm segments, with only one paper providing data on angular velocities and accelerations. The results of the different analyses suggest that the human arm is adaptive (due to its inherent mechanical redundancy), showing the ability to perform the same tasks using differing kinematic strategies. Therefore, the principal interest for the designer of upper limb orthoses should be the work-space defined by the start and end points of the hand, and the maintenance of the desired hand orientation when performing these tasks.