{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,25]],"date-time":"2026-04-25T04:27:23Z","timestamp":1777091243680,"version":"3.51.4"},"reference-count":47,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2023,8,22]],"date-time":"2023-08-22T00:00:00Z","timestamp":1692662400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of University and Research (MUR)","award":["PE0000006"],"award-info":[{"award-number":["PE0000006"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Persons post-stroke experience excessive muscle co-contraction, and consequently the arm functions are compromised during the activities of daily living. Therefore, identifying instrumental outcome measures able to detect the motor strategy adopted after a stroke is a primary clinical goal. Accordingly, this study aims at verifying whether the surface electromyography (sEMG)-based co-contraction index (CCI) could be a new clinically feasible approach for assessing and monitoring patients\u2019 motor performance. Thirty-four persons post-stroke underwent clinical assessment and upper extremity kinematic analysis, including sEMG recordings. The participants were randomized into two treatment groups (robot and usual care groups). Ten healthy subjects provided a normative reference (NR). Frost\u2019s CCI was used to quantify the muscle co-contraction of three different agonist\/antagonist muscle pairs during an object-placing task. Persons post-stroke showed excessive muscle co-contraction (mean (95% CI): anterior\/posterior deltoid CCI: 0.38 (0.34\u20130.41) p = 0.03; triceps\/biceps CCI: 0.46 (0.41\u20130.50) p = 0.01) compared to NR (anterior\/posterior deltoid CCI: 0.29 (0.21\u20130.36); triceps\/biceps CCI: 0.34 (0.30\u20130.39)). After robot therapy, persons post-stroke exhibited a greater improvement (i.e., reduced CCI) in proximal motor control (anterior\/posterior deltoid change score of CCI: \u22120.02 (\u22120.07\u20130.02) p = 0.05) compared to usual care therapy (0.04 (0.00\u20130.09)). Finally, the findings of the present study indicate that the sEMG-based CCI could be a valuable tool in clinical practice.<\/jats:p>","DOI":"10.3390\/s23177320","type":"journal-article","created":{"date-parts":[[2023,8,22]],"date-time":"2023-08-22T09:10:56Z","timestamp":1692695456000},"page":"7320","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Surface-Electromyography-Based Co-Contraction Index for Monitoring Upper Limb Improvements in Post-Stroke Rehabilitation: A Pilot Randomized Controlled Trial Secondary Analysis"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5445-0088","authenticated-orcid":false,"given":"Virginia","family":"Bandini","sequence":"first","affiliation":[{"name":"IRCCS Fondazione Don Carlo Gnocchi Onlus, Via Capecelatro 66, 20148 Milan, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7486-0706","authenticated-orcid":false,"given":"Ilaria","family":"Carpinella","sequence":"additional","affiliation":[{"name":"IRCCS Fondazione Don Carlo Gnocchi Onlus, Via Capecelatro 66, 20148 Milan, Italy"}]},{"given":"Alberto","family":"Marzegan","sequence":"additional","affiliation":[{"name":"IRCCS Fondazione Don Carlo Gnocchi Onlus, Via Capecelatro 66, 20148 Milan, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8287-4881","authenticated-orcid":false,"given":"Johanna","family":"Jonsdottir","sequence":"additional","affiliation":[{"name":"IRCCS Fondazione Don Carlo Gnocchi Onlus, Via Capecelatro 66, 20148 Milan, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0948-6089","authenticated-orcid":false,"given":"Carlo Albino","family":"Frigo","sequence":"additional","affiliation":[{"name":"Department of Electronics, Information and Bioengineering (DEIB), Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy"}]},{"given":"Laura","family":"Avanzino","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Section of Human Physiology, University of Genoa, 16132 Genoa, Italy"},{"name":"IRCCS Ospedale Policlinico San Martino, IRCCS, 16132 Genoa, Italy"}]},{"given":"Elisa","family":"Pelosin","sequence":"additional","affiliation":[{"name":"IRCCS Ospedale Policlinico San Martino, IRCCS, 16132 Genoa, Italy"},{"name":"Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal Child Health, University of Genoa, 16132 Genova, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7797-2399","authenticated-orcid":false,"given":"Maurizio","family":"Ferrarin","sequence":"additional","affiliation":[{"name":"IRCCS Fondazione Don Carlo Gnocchi Onlus, Via Capecelatro 66, 20148 Milan, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3821-6256","authenticated-orcid":false,"given":"Tiziana","family":"Lencioni","sequence":"additional","affiliation":[{"name":"IRCCS Fondazione Don Carlo Gnocchi Onlus, Via Capecelatro 66, 20148 Milan, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s12984-020-0646-1","article-title":"Effects of Robot Therapy on Upper Body Kinematics and Arm Function in Persons Post Stroke: A Pilot Randomized Controlled Trial","volume":"17","author":"Carpinella","year":"2020","journal-title":"J. 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