{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T18:23:59Z","timestamp":1771698239288,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2024,8,15]],"date-time":"2024-08-15T00:00:00Z","timestamp":1723680000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior\u2014Brasil (CAPES)","award":["459203\/2014-2"],"award-info":[{"award-number":["459203\/2014-2"]}]},{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)","doi-asserted-by":"publisher","award":["459203\/2014-2"],"award-info":[{"award-number":["459203\/2014-2"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>(1) Background: The Modified Ashworth Scale (MAS) is commonly used clinically to evaluate spasticity, but its qualitative nature introduces subjectivity. We propose a novel metric scale to quantitatively measure spasticity using mechanomyography (MMG) to mitigate these subjective effects. (2) Methods: The flexor and extensor muscles of knee and elbow joints were assessed with the Modified Ashworth Scale (MAS) during the acquisition of mechanomyography (MMG) data. The median absolute amplitude of the MMG signals was utilized as a key descriptor. An algorithm was developed to normalize the MMG signals to a universal gravitational (G) acceleration scale, aligning them with the limits and range of MAS. (3) Results: We evaluated 34 lower and upper limbs from 22 volunteers (average age 39.91 \u00b1 13.77 years) of both genders. Polynomial regression provided the best fit (R2 = 0.987), with negligible differences (mean of 0.001 G) between the MAS and MMG. We established three numerical sets for the median, minimum, and maximum MMG(G) values corresponding to each MAS range, ensuring consistent alignment of the Modified Ashworth levels with our proposed scale. (4) Conclusions: Muscle spasticity can now be quantitatively and semi-automatically evaluated using our algorithm and instrumentation, enhancing the objectivity and reliability of spasticity assessments.<\/jats:p>","DOI":"10.3390\/s24165276","type":"journal-article","created":{"date-parts":[[2024,8,15]],"date-time":"2024-08-15T03:49:36Z","timestamp":1723693776000},"page":"5276","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Mechanomyography-Based Metric Scale for Spasticity: A Pilot Descriptive Observational Study"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8090-9457","authenticated-orcid":false,"given":"Elgison L.","family":"dos Santos","sequence":"first","affiliation":[{"name":"Centro Universit\u00e1rio Internacional Uninter, Curitiba 80020-000, PR, Brazil"},{"name":"Graduate Program in Health Technology, Pontif\u00edcia Universidade Cat\u00f3lica do Paran\u00e1, Curitiba 80215-901, PR, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3014-856X","authenticated-orcid":false,"given":"Eduardo M.","family":"Scheeren","sequence":"additional","affiliation":[{"name":"Graduate Program in Health Technology, Pontif\u00edcia Universidade Cat\u00f3lica do Paran\u00e1, Curitiba 80215-901, PR, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7040-6255","authenticated-orcid":false,"given":"Guilherme N.","family":"Nogueira-Neto","sequence":"additional","affiliation":[{"name":"Graduate Program in Health Technology, Pontif\u00edcia Universidade Cat\u00f3lica do Paran\u00e1, Curitiba 80215-901, PR, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3890-1595","authenticated-orcid":false,"given":"Eddy","family":"Krueger","sequence":"additional","affiliation":[{"name":"Anatomy Department, State University of Londrina, Londrina 86057-970, PR, Brazil"},{"name":"Graduate Program in Electrical Engineering, State University of Londrina, Londrina 86057-970, PR, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4203-4140","authenticated-orcid":false,"given":"Nathalia","family":"Peixoto","sequence":"additional","affiliation":[{"name":"Department of Bioengineering, George Mason University, Fairfax, VA 22030, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8051-8453","authenticated-orcid":false,"given":"Percy","family":"Nohama","sequence":"additional","affiliation":[{"name":"Graduate Program in Health Technology, Pontif\u00edcia Universidade Cat\u00f3lica do Paran\u00e1, Curitiba 80215-901, PR, Brazil"},{"name":"Graduate Program in Electrical and Computing Engineering, Universidade Tecnol\u00f3gica Federal do Paran\u00e1, Curitiba 80230-901, PR, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,15]]},"reference":[{"key":"ref_1","first-page":"154","article-title":"Comparison of Modified Ashworth Scale and Hoffmann Reflex in Study of Spasticity","volume":"48","author":"Kohan","year":"2010","journal-title":"Acta Medica Iran."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1029","DOI":"10.1590\/S0004-282X2009000600013","article-title":"Predictive factors for spasticity among ischemic stroke patients","volume":"67","author":"Moura","year":"2009","journal-title":"Arq. 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