Elbow motion patterns during daily activity

Background: 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. Methods: 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 pronationsupination angles. Results: The elbow flexion-extension postures that were most common ranged from 60 degrees-100 degrees for both the dominant and nondominant extremities averaging 44% +/- 4% and 35% 14% 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. Conclusion: Both flexion-extension and pronation-supination motions occur more commonly in the dominant arm, and the dominant ann is more commonly in pronation. These data provide a baseline for assessing treatment outcomes, ergonomic studies, and elbow arthroplasty wear testing. (C) 2020 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.