{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T17:58:19Z","timestamp":1790618299457,"version":"4.1.0"},"reference-count":36,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T00:00:00Z","timestamp":1790467200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Background\/Objectives: To compare lower-limb muscle architecture and strength between men with radiographic axial spondyloarthritis (r-axSpA) and controls. Methods: In this controlled cross-sectional study, 30 men with r-axSpA and 30 age-matched healthy men underwent bilateral ultrasound assessment of the vastus lateralis (VL), gastrocnemius medialis (GM), gastrocnemius lateralis (GL), and tibialis anterior (TA). Fascicle length was derived trigonometrically. Strength was assessed using hand-held dynamometry. Results: Differences represent r-axSpA minus controls, with 95% confidence intervals. VL, GM, and GL thickness differences were \u22120.32 (\u22120.50 to \u22120.13), \u22120.18 (\u22120.34 to \u22120.02), and \u22120.21 (\u22120.36 to \u22120.05) cm, respectively. Pennation-angle differences were \u22122.38 (\u22123.48 to \u22121.28), \u22121.99 (\u22123.35 to \u22120.63), \u22122.46 (\u22123.69 to \u22121.23), and 0.26 (\u22120.68 to 1.22) degrees for VL, GM, GL, and the TA superficial region, respectively. TA superficial-region thickness and derived fascicle length were greater: +0.53 (0.29 to 0.78) and +2.40 (1.36 to 3.45) cm, respectively. Knee extensor, ankle dorsiflexor, and ankle plantar flexor strength differences were \u221286.3 (\u2212123.6 to \u221248.8), \u221252.0 (\u221278.2 to \u221226.6), and \u221257.9 (\u221292.3 to \u221224.1) N, respectively. Conclusions: Men with r-axSpA showed greater TA superficial-region thickness and derived fascicle length alongside lower dorsiflexion strength. These preliminary findings require confirmation in independent studies using validated measurement methods.<\/jats:p>","DOI":"10.3390\/jcm15197515","type":"journal-article","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T16:50:54Z","timestamp":1790614254000},"page":"7515","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Lower-Limb Muscle Architecture and Strength in Men with Radiographic Axial Spondyloarthritis: A Cross-Sectional Ultrasound Study"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6303-5735","authenticated-orcid":false,"given":"Mehmet Serkan","family":"K\u0131l\u0131\u00e7o\u011flu","sequence":"first","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Faculty of Medicine, Bezmialem Vak\u0131f University, Adnan Menderes Boulevard, Istanbul 34093, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]},{"given":"Mert","family":"Kara","sequence":"additional","affiliation":[{"name":"Physical Medicine and Rehabilitation Clinic, \u00d6zel Ya\u015fam Hastanesi, Antalya 07160, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"supervision","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1255-4767","authenticated-orcid":false,"given":"Esra","family":"K\u00fclt\u00fcr \u00c7aml\u0131","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Faculty of Medicine, Bezmialem Vak\u0131f University, Adnan Menderes Boulevard, Istanbul 34093, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Delal","family":"Lutfi","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, K\u00fctahya City Hospital, K\u00fctahya 43100, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7467-4073","authenticated-orcid":false,"given":"Bu\u011fra","family":"\u0130nce","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, \u0130zmir Faculty of Medicine, University of Health Sciences T\u00fcrkiye, \u0130zmir City Hospital, \u0130zmir 35540, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Teoman","family":"Ayd\u0131n","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Faculty of Medicine, Bezmialem Vak\u0131f University, Adnan Menderes Boulevard, Istanbul 34093, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4567-8133","authenticated-orcid":false,"given":"Ozan Volkan","family":"Yurdakul","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Faculty of Medicine, Bezmialem Vak\u0131f University, Adnan Menderes Boulevard, Istanbul 34093, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3079","DOI":"10.1007\/s10067-021-05679-7","article-title":"Ankylosing spondylitis risk factors: A systematic literature review","volume":"40","author":"Hwang","year":"2021","journal-title":"Clin. 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