{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T23:19:01Z","timestamp":1776381541991,"version":"3.51.2"},"reference-count":49,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2025,9,2]],"date-time":"2025-09-02T00:00:00Z","timestamp":1756771200000},"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>Physical rehabilitation is crucial for injury recovery, offering pain relief and faster healing. However, traditional methods rely heavily on in-person professional feedback, which can be time-consuming, expensive, and prone to human error, limiting accessibility and effectiveness. As a result, patients are often encouraged to perform exercises at home; however, due to the lack of professional guidance, motivation dwindles and adherence becomes a challenge. To address this, this paper proposes a smartphone-based solution that enables patients to receive exercise feedback independently. This paper reviews current Computer Vision systems for assessing rehabilitation exercises and introduces an intelligent system designed to assist patients in their recovery. Our proposed system uses motion tracking based on Computer Vision, analyzing videos recorded with a smartphone. With accessibility as a priority, the system is evaluated against the advanced Qualysis Motion Capture System using a dataset labeled by expert physicians. The framework focuses on human pose detection and movement quality assessment, aiming to reduce recovery times, minimize human error, and make rehabilitation more accessible. This proof-of-concept study was conducted as a pilot evaluation involving 15 participants, consistent with earlier work in the field, and serves to assess feasibility before scaling to larger datasets. This innovative approach has the potential to transform rehabilitation, providing accurate feedback and support to patients without the need for in-person supervision or specialized equipment.<\/jats:p>","DOI":"10.3390\/s25175428","type":"journal-article","created":{"date-parts":[[2025,9,2]],"date-time":"2025-09-02T12:04:28Z","timestamp":1756814668000},"page":"5428","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Smartphone-Based Markerless Motion Capture for Accessible Rehabilitation: A Computer Vision Study"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8661-3080","authenticated-orcid":false,"given":"Bruno","family":"Cunha","sequence":"first","affiliation":[{"name":"CINTESIS@RISE, CINTESIS.UPT, Department of Science and Technology, Portucalense University, Rua Dr. Ant\u00f3nio Bernardino de Almeida 541, 4200-072 Porto, Portugal"},{"name":"Porto Research, Technology & Innovation Center, Polytechnic of Porto (IPP), Rua Arquitecto Lob\u00e3o Vital, 172, 4200-375 Porto, Portugal"}]},{"given":"Jos\u00e9","family":"Ma\u00e7\u00e3es","sequence":"additional","affiliation":[{"name":"FEUP\u2014Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6102-6165","authenticated-orcid":false,"given":"Ivone","family":"Amorim","sequence":"additional","affiliation":[{"name":"Porto Research, Technology & Innovation Center, Polytechnic of Porto (IPP), Rua Arquitecto Lob\u00e3o Vital, 172, 4200-375 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1018","DOI":"10.2522\/ptj.20100343","article-title":"Determinants of Utilization and Expenditures for Episodes of Ambulatory Physical Therapy Among Adults","volume":"91","author":"Machlin","year":"2011","journal-title":"Phys. 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