{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T14:20:00Z","timestamp":1785507600886,"version":"3.56.0"},"reference-count":40,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,15]],"date-time":"2023-03-15T00:00:00Z","timestamp":1678838400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Deutsche Forschungsgemeinschaft (DFG)\u2014German Research Foundation","award":["GRK 2198\u2014277536708"],"award-info":[{"award-number":["GRK 2198\u2014277536708"]}]},{"name":"Deutsche Forschungsgemeinschaft (DFG)\u2014German Research Foundation","award":["01EC1907B"],"award-info":[{"award-number":["01EC1907B"]}]},{"DOI":"10.13039\/501100002347","name":"Bundesministerium f\u00fcr Bildung und Forschung (BMBF, Federal Ministry of Education and Research)","doi-asserted-by":"publisher","award":["GRK 2198\u2014277536708"],"award-info":[{"award-number":["GRK 2198\u2014277536708"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002347","name":"Bundesministerium f\u00fcr Bildung und Forschung (BMBF, Federal Ministry of Education and Research)","doi-asserted-by":"publisher","award":["01EC1907B"],"award-info":[{"award-number":["01EC1907B"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Myasthenia gravis (MG) is often accompanied with muscle weakness; however, little is known about mechanical adaptions of the affected muscles. As the latter can be assessed using ultrasound shear wave elastography (SWE), this study characterizes the biceps brachii muscle of 11 patients with MG and compares them with that of 14 healthy volunteers. Simultaneous SWE, elbow torque and surface electromyography measurements were performed during rest, maximal voluntary contraction (MVC) and submaximal isometric contractions (up to 25%, 50% and 75% MVC) at different elbow angles from flexion to extension. We found that, with increasing elbow angle, maximum elbow torque decreased (p &lt; 0.001), whereas muscle stiffness increased during rest (p = 0.001), MVC (p = 0.004) and submaximal contractions (p &lt; 0.001). Muscle stiffness increased with increasing contraction intensities during submaximal contractions (p &lt; 0.001). In comparison to the healthy cohort, muscle stiffness of MG patients was 2.1 times higher at rest (p &lt; 0.001) but 8.93% lower in active state (75% MVC, p = 0.044). We conclude that (i) increased muscle stiffness shown by SWE during rest might be an indicator of MG, (ii) SWE reflects muscle weakness and (iii) SWE can be used to characterize MG muscle.<\/jats:p>","DOI":"10.3390\/diagnostics13061108","type":"journal-article","created":{"date-parts":[[2023,3,15]],"date-time":"2023-03-15T04:39:45Z","timestamp":1678855185000},"page":"1108","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Characterization of Muscle Weakness Due to Myasthenia Gravis Using Shear Wave Elastography"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2405-863X","authenticated-orcid":false,"given":"Manuela","family":"Zimmer","sequence":"first","affiliation":[{"name":"Institute of Structural Mechanics and Dynamics in Aerospace Engineering, University of Stuttgart, Pfaffenwaldring 27, 70569 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7575-0020","authenticated-orcid":false,"given":"Benedict","family":"Kleiser","sequence":"additional","affiliation":[{"name":"Department of Epileptology, Hertie-Institute for Clinical Brain Research, University of T\u00fcbingen, Hoppe-Seyler-Str. 3, 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2039-5498","authenticated-orcid":false,"given":"Justus","family":"Marquetand","sequence":"additional","affiliation":[{"name":"Department of Epileptology, Hertie-Institute for Clinical Brain Research, University of T\u00fcbingen, Hoppe-Seyler-Str. 3, 72076 T\u00fcbingen, Germany"},{"name":"Department of Neural Dynamics and Magnetoencephalography, Hertie-Institute for Clinical Brain Research, University of T\u00fcbingen, Otfried-M\u00fcller-Str. 25, 72076 T\u00fcbingen, Germany"},{"name":"MEG-Center, University of T\u00fcbingen, Otfried-M\u00fcller-Str. 47, 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5634-3913","authenticated-orcid":false,"given":"Filiz","family":"Ates","sequence":"additional","affiliation":[{"name":"Institute of Structural Mechanics and Dynamics in Aerospace Engineering, University of Stuttgart, Pfaffenwaldring 27, 70569 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"516","DOI":"10.1186\/s12967-021-03185-7","article-title":"Global Prevalence of Myasthenia Gravis and the Effectiveness of Common Drugs in Its Treatment: A Systematic Review and Meta-Analysis","volume":"19","author":"Salari","year":"2021","journal-title":"J. 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