Elbow motion patterns during daily activity.

Abstract

This in vivo kinematic study was developed to ascertain (1) elbow posture and motion during daily activities and (2) to compare motions of the dominant and nondominant elbows. Forty-six subjects wore a custom instrumented shirt to continuously measure elbow posture and motion for the waking hours of 1 day. The 3D orientations of each of the forearm and humerus sensors enabled calculation of elbow flexion-extension and pronation-supination angles. The elbow flexion-extension postures that were most common ranged from 60°-100° for both the dominant and nondominant extremities averaging 44% ± 4% and 35% ± 4% of the day, respectively. When elbow flexion motions were calculated, there were a large number of motions over a wide distribution of flexion angles, with the dominant side exhibiting significantly more motions per hour than the nondominant side. Both flexion-extension and pronation-supination motions occur more commonly in the dominant arm, and the dominant arm is more commonly in pronation. These data provide a baseline for assessing treatment outcomes, ergonomic studies, and elbow arthroplasty wear testing.