Reachable workspace with real-time motion capture feedback to quantify upper extremity function: A study on children with brachial plexus birth injury

• Published in: Journal of biomechanics Vol. 132; p. 110939
• Main Authors: Richardson, R. Tyler, Russo, Stephanie A., Chafetz, Ross S., Warshauer, Spencer, Nice, Emily, Kozin, Scott H., Zlotolow, Dan A., Richards, James G.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.02.2022; Elsevier Limited
• Subjects: Birth; Birth Injuries; Brachial Plexus; Child; Children; Data collection; Evaluation; Feedback; Function; Humans; Injuries; Limbs; Motion capture; Motion detection; Patients; Physical therapists; Range of Motion, Articular; Reach; Reachable workspace; Real time; Upper Extremity; Variance analysis; Visual perception; Function; Reach; Upper extremity; Reachable workspace; Brachial plexus
• ISSN: 0021-9290; 1873-2380; 1873-2380
• DOI: 10.1016/j.jbiomech.2021.110939

Clinical upper extremity (UE) functional assessments and motion capture measures are limited to a set of postures and/or motions that may provide an incomplete evaluation of UE functionality. Reachable workspace analysis offers a more global assessment of UE function, but is reliant on patient compliance with instructions and may result in underestimates of a patient’s true UE function. This study evaluated a clinical tool that incorporates real-time visual feedback with motion capture to provide an innovative means of engaging patients to ensure a ‘best effort’ quantification of their available UE workspace. Reachable workspace for 10 children with brachial plexus birth injury was collected with and without real-time feedback on the affected and unaffected limbs. Real-time feedback consisted of subjects reaching for virtual targets surrounding their physical space using a virtual cursor controlled by the real-time location of their hand. Real-time feedback resulted in significantly greater workspace in multiple regions on both the affected (3/6 octants; mean differences 10.8%-20.0%) and unaffected (6/6 octants; mean differences 24.3%-40.0%) limbs. Use of real-time feedback also yielded significant interlimb differences in workspace across more regions (4/6 octants; mean differences 29.0%-39.9% vs. 1/6 octants; mean difference 17%). Finally, real-time feedback resulted in significant interlimb differences in median reach distance across more regions (4/6 octants; mean differences 7.5%-44.8% vs. 1/6 octants; mean difference 11.2%). A reachable workspace tool with real-time feedback results in more workspace and UE function recorded and offers a highly visual and intuitive depiction of a patient’s UE abilities.