{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T06:37:21Z","timestamp":1780382241477,"version":"3.54.1"},"reference-count":45,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,8,2]],"date-time":"2023-08-02T00:00:00Z","timestamp":1690934400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Italian Ministry of Health, \u201cRicerca Corrente\u201d"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JPM"],"abstract":"<jats:p>The patellofemoral joint (PFJ) is a complex articulation between the patella and the femur which is involved in the extensor mechanism of the knee. Patellofemoral disorders can be classified into objective patellar instability, potential patellar instability, and patellofemoral pain syndrome. Anatomical factors such as trochlear dysplasia, patella alta, and the tibial tuberosity\u2013trochlear groove (TT-TG) distance contribute to instability. Patellofemoral instability can result in various types of dislocations, and the frequency of dislocation can be categorized as recurrent, habitual, or permanent. Primary patellar dislocation requires diagnostic framing, including physical examination and imaging. Magnetic resonance imaging (MRI) is essential for assessing the extent of damage, such as bone bruises, osteochondral fractures, and medial patellofemoral ligament (MPFL) rupture. Treatment options for primary dislocation include urgent surgery for osteochondral fragments or conservative treatment for cases without lesions. Follow-up after treatment involves imaging screening and assessing principal and secondary factors of instability. Detecting and addressing these factors is crucial for preventing recurrent dislocations and optimizing patient outcomes.<\/jats:p>","DOI":"10.3390\/jpm13081225","type":"journal-article","created":{"date-parts":[[2023,8,2]],"date-time":"2023-08-02T11:04:38Z","timestamp":1690974278000},"page":"1225","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Framing Patellar Instability: From Diagnosis to the Treatment of the First Episode"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5296-650X","authenticated-orcid":false,"given":"Davide Maria","family":"Maggioni","sequence":"first","affiliation":[{"name":"Residency Program in Orthopaedics and Traumatology, University of Milan, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1067-7424","authenticated-orcid":false,"given":"Riccardo","family":"Giorgino","sequence":"additional","affiliation":[{"name":"Residency Program in Orthopaedics and Traumatology, University of Milan, 20122 Milan, Italy"},{"name":"IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7518-5773","authenticated-orcid":false,"given":"Carmelo","family":"Messina","sequence":"additional","affiliation":[{"name":"IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy"},{"name":"Dipartimento di Scienze Biomediche per la Salute, Universit\u00e0 degli Studi di Milano, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7989-9861","authenticated-orcid":false,"given":"Domenico","family":"Albano","sequence":"additional","affiliation":[{"name":"IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy"},{"name":"Dipartimento di Scienze Biomediche, Chirurgiche ed Odontoiatriche, Universit\u00e0 degli Studi di Milano, Via della Commenda 10, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9341-7187","authenticated-orcid":false,"given":"Giuseppe Michele","family":"Peretti","sequence":"additional","affiliation":[{"name":"IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy"},{"name":"Dipartimento di Scienze Biomediche per la Salute, Universit\u00e0 degli Studi di Milano, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Mangiavini","sequence":"additional","affiliation":[{"name":"IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy"},{"name":"Dipartimento di Scienze Biomediche per la Salute, Universit\u00e0 degli Studi di Milano, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1007\/s00167-012-2274-1","article-title":"Patella instability: Building bridges across the ocean a historic review","volume":"21","author":"Arendt","year":"2013","journal-title":"Knee Surg. 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