{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T08:06:53Z","timestamp":1784016413743,"version":"3.55.0"},"reference-count":23,"publisher":"Springer Science and Business Media LLC","issue":"9","license":[{"start":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T00:00:00Z","timestamp":1778198400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T00:00:00Z","timestamp":1778198400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"ALF","award":["ALFGBG-1006741"],"award-info":[{"award-number":["ALFGBG-1006741"]}]},{"name":"ALF","award":["ALFBGB-1006741"],"award-info":[{"award-number":["ALFBGB-1006741"]}]},{"DOI":"10.13039\/501100005350","name":"Centrum f\u00f6r idrottsforskning","doi-asserted-by":"publisher","award":["P2024-0126"],"award-info":[{"award-number":["P2024-0126"]}],"id":[{"id":"10.13039\/501100005350","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005760","name":"University of Gothenburg","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100005760","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Skeletal Radiol"],"published-print":{"date-parts":[[2026,9]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>Ultrasound gap distance has been proposed as a supportive triage input within protocol-based pathways after acute Achilles tendon rupture. We assessed intra-\/inter-rater reliability of gap measurement and the extent of classification uncertainty around a 5\u2014mm threshold.<\/jats:p>\n                    <jats:p>Retrospective observer-agreement study without a definitive reference standard, using protocol-acquired stored ultrasound cine loops from 30 clinically diagnosed complete acute ruptures in a prospectively collected cohort.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Retrospective observer-agreement study without a definitive reference standard, using protocol-acquired stored ultrasound cine loops from 30 clinically diagnosed complete acute ruptures in a prospectively collected cohort. Two blinded musculoskeletal radiologists re-reviewed stored cine loops and measured tendon-gap distance in two sessions each (\u2265\u20094\u00a0weeks apart). We calculated intraclass correlation coefficients (ICC), Bland\u2013Altman mean difference and 95% limits of agreement (LoA), and standard error of measurement (SEM). Agreement at the 5\u2014mm protocol cut-point was assessed using Cohen\u2019s \u03ba and Gwet\u2019s AC1. Using SEM, we derived 90% confidence zones indicating firm classification versus a grey zone where repeat measurement or second read may be considered.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Intra-rater ICC(2,1) was 0.88 (95% CI 0.83\u20130.91) and 0.94 (0.82\u20130.97); SEMs were 1.57 and 1.19\u00a0mm. Inter-rater bias was\u2009+\u20091.12\u00a0mm with LoA\u2009\u2212\u20093.85 to 6.10\u00a0mm. Agreement for study experimental pathway classification at the 5\u2014mm cut-point (operative vs non-operative) was moderate (\u03ba\u2009=\u20090.60; AC1\u2009=\u20090.61), with 6\/30 examinations classified differently. SEM-based 90% zones were\u2009\u2264\u20092.42 and\u2009\u2265\u20097.58\u00a0mm (rater 1) and\u2009\u2264\u20093.04 and\u2009\u2265\u20096.96\u00a0mm (rater 2); a conservative cross-rater rule suggested\u2009\u2264\u20092.05 or\u2009\u2265\u20097.95\u00a0mm.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Gap measurement shows good relative reliability, but uncertainty near 5\u00a0mm can alter classification. Reporting LoA\/SEM alongside ICC and flagging a grey zone may reduce misclassification in borderline cases.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00256-026-05243-x","type":"journal-article","created":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T09:12:13Z","timestamp":1778490733000},"page":"2301-2313","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Ultrasound gap measurement after acute Achilles rupture is reliable overall but uncertain near a 5\u2014mm decision threshold"],"prefix":"10.1007","volume":"55","author":[{"given":"Dan","family":"Mocanu","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katarzyna","family":"Bokwa-D\u0105browska","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elin","family":"Larsson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katarina Nilsson","family":"Helander","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0334-7232","authenticated-orcid":false,"given":"Pawel","family":"Szaro","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,5,8]]},"reference":[{"issue":"14","key":"5243_CR1","first-page":"2466","volume":"92","author":"CP Chiodo","year":"2010","unstructured":"Chiodo CP, Glazebrook M, Bluman EM, Cohen BE, Femino JE, Giza E, et al. 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The study was approved by the Swedish Ethical Review Authority (2019\u201405457). All procedures conformed to the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval and consent to participate"}},{"value":"Does not apply. The manuscript does not contain the data of individuals in any form.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}]}}