{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T00:36:54Z","timestamp":1777509414688,"version":"3.51.4"},"reference-count":11,"publisher":"SAGE Publications","issue":"10","license":[{"start":{"date-parts":[[2025,6,2]],"date-time":"2025-06-02T00:00:00Z","timestamp":1748822400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Acta Radiol"],"published-print":{"date-parts":[[2025,10]]},"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Acute findings of patellar dislocation in magnetic resonance imaging (MRI) can diminish with time; therefore, additional findings may help diagnosis of chronic patellofemoral instability.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>To define a previously undescribed MRI finding\u2014medial parapatellar triangle (MPT)\u2014and to examine the diagnostic value of the disruption of MPT in chronic patellofemoral instability.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Material and Methods<\/jats:title>\n                    <jats:p>Our study was performed on 24 knees that underwent medial patellofemoral ligament reconstruction for chronic patellofemoral instability and 48 knees of patients with similar age and sex as control group. MPT was defined as an acute-angled triangle delineated by patellar cartilage, medial retinaculum, and medial femoral condyle in the section passing through the upper third of the patella on axial proton-density weighted with fat saturation (PD fat-sat) MRI scans. Disruption of MPT was assessed by two authors blinded to the diagnosis. Inter- and intra-observer reliability was assessed using Cohen's \u03ba test. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each observer and observation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>In the study group, the triangular structure was disrupted in 18 knees for the first observer's first observation, and 17 knees for the second observation; for the second observer, it was 15 knees and 17 knees, respectively. In the control group, the numbers were 2, 6, 1, and 3, respectively. Mean Cohen's \u03ba statistic was 0.81 (range=0.73\u20130.87). Sensitivity, specificity, PPV, and NPV were 66.7%\u201375%, 87.5%\u201397.9%, 72.7%\u201394.4%, and 84%\u201388.5%. respectively.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Disruption of MPT is an additional finding that may help the diagnosis of chronic patellofemoral instability.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1177\/02841851251346704","type":"journal-article","created":{"date-parts":[[2025,6,2]],"date-time":"2025-06-02T03:58:06Z","timestamp":1748836686000},"page":"1117-1121","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":0,"title":["Disrupted medial parapatellar triangle as an MRI finding of chronic patellofemoral instability"],"prefix":"10.1177","volume":"66","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8167-6146","authenticated-orcid":false,"given":"Fatih","family":"Bar\u00e7a","sequence":"first","affiliation":[{"name":"Department of Orthopedics and Traumatology, Ankara Etlik City Hospital, Ankara, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9986-1905","authenticated-orcid":false,"given":"Ekin Bar\u0131\u015f","family":"Demir","sequence":"additional","affiliation":[{"name":"Department of Orthopedics and Traumatology, Ankara Etlik City Hospital, Ankara, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9403-2369","authenticated-orcid":false,"given":"Burak Menderes","family":"Akdo\u011fan","sequence":"additional","affiliation":[{"name":"Department of Orthopedics and Traumatology, Rize State Hospital, Rize, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8278-220X","authenticated-orcid":false,"given":"Muhammet","family":"Hayat","sequence":"additional","affiliation":[{"name":"Department of Orthopedics and Traumatology, Tokat Turhal State Hospital, Tokat, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mutlu","family":"Akdo\u011fan","sequence":"additional","affiliation":[{"name":"Department of Orthopedics and Traumatology, Ankara Etlik City Hospital, Ankara, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Halis At\u0131l","family":"Atilla","sequence":"additional","affiliation":[{"name":"Department of Orthopedics and Traumatology, Ankara Etlik City Hospital, Ankara, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[2025,6,2]]},"reference":[{"key":"e_1_3_3_2_2","doi-asserted-by":"publisher","DOI":"10.1136\/bjsports-2014-093450"},{"key":"e_1_3_3_3_2","doi-asserted-by":"publisher","DOI":"10.1148\/radiology.189.1.8372201"},{"key":"e_1_3_3_4_2","doi-asserted-by":"publisher","DOI":"10.1007\/s00167-011-1775-7"},{"key":"e_1_3_3_5_2","doi-asserted-by":"publisher","DOI":"10.1148\/radiol.2253011578"},{"key":"e_1_3_3_6_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.otsr.2014.12.001"},{"key":"e_1_3_3_7_2","doi-asserted-by":"publisher","DOI":"10.1007\/s10140-012-1073-9"},{"key":"e_1_3_3_8_2","doi-asserted-by":"publisher","DOI":"10.1007\/s00167-004-0592-7"},{"key":"e_1_3_3_9_2","doi-asserted-by":"publisher","DOI":"10.1097\/00004728-200111000-00021"},{"key":"e_1_3_3_10_2","first-page":"17","article-title":"Medial patellofemoral ligament injury patterns and associated pathology in lateral patella dislocation: an MRI study","volume":"1","author":"Guerrero P","year":"2009","unstructured":"Guerrero P, Li X, Patel K, et al. Medial patellofemoral ligament injury patterns and associated pathology in lateral patella dislocation: an MRI study. Sports Med Arthrosc Rehabil Ther Technol 2009;1:17.","journal-title":"Sports Med Arthrosc Rehabil Ther Technol"},{"key":"e_1_3_3_11_2","doi-asserted-by":"publisher","DOI":"10.1177\/2325967120967338"},{"key":"e_1_3_3_12_2","doi-asserted-by":"publisher","DOI":"10.1177\/0363546512457558"}],"container-title":["Acta Radiologica"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/02841851251346704","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1177\/02841851251346704","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/02841851251346704","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T15:34:43Z","timestamp":1777390483000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/02841851251346704"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,6,2]]},"references-count":11,"journal-issue":{"issue":"10","published-print":{"date-parts":[[2025,10]]}},"alternative-id":["10.1177\/02841851251346704"],"URL":"https:\/\/doi.org\/10.1177\/02841851251346704","relation":{},"ISSN":["0284-1851","1600-0455"],"issn-type":[{"value":"0284-1851","type":"print"},{"value":"1600-0455","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,6,2]]}}}