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Inner, close-to-body reachable workspace to quantify upper extremity mobility: a study on children with brachial
R Tyler Richardson1, Stephanie A Russo2, Ross S Chafetz3
1Pennsylvania State University Harrisburg, 777 W Harrisburg Pike, Middletown, PA 17057, USA.
Insights
Children with brachial plexus birth injury (BPBI) have significantly reduced close-to-body upper extremity (UE) reachable workspace compared to their unaffected limb. This finding highlights a new way to assess UE mobility in BPBI patients.
Area of Science:
- Biomedical Engineering
- Rehabilitation Science
- Pediatric Orthopedics
Background:
- Brachial plexus birth injury (BPBI) causes varied upper extremity (UE) mobility impairments.
- Current assessments may not fully capture UE movement limitations, especially close-to-body tasks.
- Reachable workspace (RW) measures UE mobility but often focuses on far-from-body movements.
Purpose of the Study:
- To evaluate a motion capture-based RW approach for assessing inner, close-to-body UE mobility in children with BPBI.
- To determine if the affected limb in children with BPBI exhibits reduced inner RW compared to the unaffected limb.
- To correlate workspace deficits with common UE movement impairments in BPBI.
Main Methods:
- Fifteen children with unilateral BPBI were assessed using motion capture technology.
- Real-time visual feedback was employed to measure UE reachable workspace around the head, thorax, and abdomen.
- A two-way repeated measures ANOVA analyzed the percentage of workspace reached in different body regions.
Main Results:
- The affected UE had significantly less reachable workspace than the unaffected UE in 8 out of 9 assessed regions.
- Workspace deficits ranged from 17.0% to 49.2% across different body regions.
- These deficits align with typical movement impairments observed in BPBI patients.
Conclusions:
- Motion capture-based assessment of inner, close-to-body reachable workspace is a clinically relevant tool for evaluating UE mobility in children with BPBI.
- This method provides valuable insights into patient-specific movement limitations, aiding clinical decision-making and outcome assessment.
- Understanding close-to-body workspace deficits can lead to more targeted interventions and improved patient outcomes.
Abstract:
Brachial plexus birth injury (BPBI) results in individualized impairments in upper extremity (UE) mobility. A patient-specific understanding of these movement limitations is critical for optimizing decision-making and outcomes; however, current assessments may fail to capture the entirety of a patient's UE mobility. Reachable workspace quantifies an individual's global UE mobility by measuring the regions that can be reached by their hand. Despite most UE activities of daily living requiring adequate close-to-body function, current workspace approaches only assess far-from-body mobility. This study assessed the ability of a motion capture-based workspace approach to evaluate inner, close-to-body UE mobility in children with BPBI. It was hypothesized that the BPBI affected limb would have less inner, close-to-body workspace than the unaffected limb, especially in regions requiring UE movements commonly impaired in BPBI. Fifteen children with unilateral BPBI were assessed with motion capture using real-time visual feedback to measure UE workspace in all regions surrounding the body. All inner, close-to-body points reached by the hand were recorded. A two-way repeated measures ANOVA evaluated percentage workspace reached in each region surrounding the head, thorax, and abdomen. The affected limb had significantly less workspace reached than the unaffected limb for 8 of 9 regions (mean interlimb differences by region, 17.0-49.2%). Affected limb workspace deficits corresponded to common movement impairments in BPBI demonstrating the clinical relevance of this tool. Assessment of inner, close-to-body reachable workspace may provide a valuable new perspective on UE mobility to help guide clinical decision-making and outcomes assessment.
