{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,12]],"date-time":"2026-04-12T13:45:27Z","timestamp":1776001527597,"version":"3.50.1"},"reference-count":43,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,2,1]],"date-time":"2023-02-01T00:00:00Z","timestamp":1675209600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>There is a high prevalence of shoulder problems in manual wheelchair users (MWUs) with a spinal cord injury. How shoulder load relates to shoulder problems remains unclear. This study aimed to develop a machine-learning-based methodology to estimate the shoulder load in wheelchair-related activities of daily living using wearable sensors. Ten able-bodied participants equipped with five inertial measurement units (IMU) on their thorax, right arm, and wheelchair performed activities exemplary of daily life of MWUs. Electromyography (EMG) was recorded from the long head of the biceps and medial part of the deltoid. A neural network was trained to predict the shoulder load based on IMU and EMG data. Different cross-validation strategies, sensor setups, and model architectures were examined. The predicted shoulder load was compared to the shoulder load determined with musculoskeletal modeling. A subject-specific biLSTM model trained on a sparse sensor setup yielded the most promising results (mean correlation coefficient = 0.74 \u00b1 0.14, relative root-mean-squared error = 8.93% \u00b1 2.49%). The shoulder-load profiles had a mean similarity of 0.84 \u00b1 0.10 over all activities. This study demonstrates the feasibility of using wearable sensors and neural networks to estimate the shoulder load in wheelchair-related activities of daily living.<\/jats:p>","DOI":"10.3390\/s23031577","type":"journal-article","created":{"date-parts":[[2023,2,1]],"date-time":"2023-02-01T03:22:47Z","timestamp":1675221767000},"page":"1577","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Machine-Learning-Based Methodology for Estimation of Shoulder Load in Wheelchair-Related Activities Using Wearables"],"prefix":"10.3390","volume":"23","author":[{"given":"Sabrina","family":"Amrein","sequence":"first","affiliation":[{"name":"Rehabilitation Engineering Laboratory, Department of Health Science and Technology, ETH Zurich, 8049 Zurich, Switzerland"},{"name":"Swiss Paraplegic Research, Guido A. Z\u00e4chstrasse 4, 6207 Nottwil, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3070-6445","authenticated-orcid":false,"given":"Charlotte","family":"Werner","sequence":"additional","affiliation":[{"name":"Rehabilitation Engineering Laboratory, Department of Health Science and Technology, ETH Zurich, 8049 Zurich, Switzerland"},{"name":"Spinal Cord Injury Center, University Hospital Balgrist, 8008 Zurich, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1101-4267","authenticated-orcid":false,"given":"Ursina","family":"Arnet","sequence":"additional","affiliation":[{"name":"Swiss Paraplegic Research, Guido A. Z\u00e4chstrasse 4, 6207 Nottwil, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6369-583X","authenticated-orcid":false,"given":"Wiebe H. K.","family":"de Vries","sequence":"additional","affiliation":[{"name":"Swiss Paraplegic Research, Guido A. Z\u00e4chstrasse 4, 6207 Nottwil, Switzerland"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"704","DOI":"10.1038\/sj.sc.3101777","article-title":"Chronic pain in individuals with spinal cord injury: A survey and longitudinal study","volume":"43","author":"Jensen","year":"2005","journal-title":"Spinal Cord"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"501","DOI":"10.1053\/apmr.2001.21855","article-title":"Chronic pain associated with spinal cord injuries: A community survey","volume":"82","author":"Turner","year":"2001","journal-title":"Arch. Phys. Med. Rehabil."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"916","DOI":"10.1080\/10790268.2021.1881238","article-title":"MRI evaluation of shoulder pathologies in wheelchair users with spinal cord injury and the relation to shoulder pain","volume":"45","author":"Arnet","year":"2021","journal-title":"J. Spinal Cord. 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