Evidence map›Paper›PMID 41849230›Full record

ArticleMilitary medicine2026

Accurate Shoulder Angles Can Be Detected in Single Plane Motions While Body Armor is Worn: A Validation of the HumanTrak Markerless Motion Capture System.

Ayden M Mccarthy, Jodie A Wills, Auralea C Fain, Brad C Nindl, Aaron J Beach, Tim L A Doyle

Abstract readValidation Study
In one paragraph

Article in Military medicine, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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0 citing papers in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Ayden M MccarthyFaculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia.ORCID 0000-0001-8927-7484
Jodie A WillsFaculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia.
Auralea C FainFaculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia.
Brad C NindlDepartment of Sports Medicine and Nutrition in the School of Health and Rehabilitation Sciences University of Pittsburgh, Neuromuscular Research Laboratory/Warrior Human Performance Research Laboratory, Pittsburgh, PA 15203, United States.ORCID 0000-0001-7088-5930
Aaron J BeachFaculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia.ORCID 0000-0001-9514-2746
Tim L A DoyleFaculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia.ORCID 0000-0002-1227-6835

Funding

Macquarie University Research Excellence Stipend Scholarship 20224931Macquarie University Research Excellence Stipend Scholarship, VALD Performance Stipend Scholarship 20224931Office of Naval Research N62909-21-1-2015
6 · The paper itself

Abstract

introductionMeasuring shoulder mobility is essential for assessing function, especially in occupational settings like the military, where movement tasks in the frontal and sagittal planes are involved. Markerless motion capture systems like the HumanTrak may provide an expedient field platform to quantify upper body kinematics in occupational settings because of their portability. Further validation of these systems against established methodologies, such as marker-based motion capture, is required before upscaling their use. MATERIALS AND

methodsSeventeen participants (7 males and 10 females; age, 25 ± 7 years; stature, 1.70 ± 0.08 m; mass, 72.26 ± 15.09 kg) completed standardized fixed-range shoulder flexion, extension, abduction, and adduction tasks with and without body armor for 3 systems: HumanTrak, 2D video capture, and 3D marker-based motion capture. Joint angles were calculated using planar and Euler algorithms. The HumanTrak's relative and absolute validity was compared against these established methodologies.

resultsGenerally, valid relative and absolute results were found, with Pearson correlations (r) ranging from 0.56 to 0.93 and root mean square errors ranging from 2.51° to 7.35° for shoulder flexion, extension, and abduction with and without body armor. Shoulder adduction measures were generally invalid, as r values ranged from -0.24 to 0.77, and with root mean square errors ranging from 5.27° to 8.42°.

conclusionsThe HumanTrak's validity is comparable to that of existing field expedient markerless motion capture systems in estimating shoulder joint angles in abduction and the sagittal plane. When movements are standardized to a singular plane of motion and a neutral spine is assumed, valid results can be measured for shoulder flexion, extension, and abduction with and without body armor. Shoulder adduction was generally invalid for both body armor and no body armor conditions, likely because of its multi-planar nature and axial trunk rotation.

Indexed as

Motion CaptureRange of Motion, ArticularShoulderShoulder JointAdultBiomechanical PhenomenaFemaleHumansMaleMovementReproducibility of Results

Identifiers

PMID41849230
PMCPMC13542619

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.