{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T06:48:25Z","timestamp":1785739705085,"version":"3.56.0"},"reference-count":27,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T00:00:00Z","timestamp":1785715200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background\/Objectives: Patella alta contributes to patellofemoral (PF) maltracking and anterior knee pain, but the agreement of patellar-height indices across imaging modalities and their clinical relevance remain uncertain. We aimed to estimate the prevalence of patella alta when using each index, quantify inter-method agreement, and quantify patella alta\u2019s associations with Hoffa\u2019s fat-pad impingement, patellar chondromalacia, and tibial tubercle\u2013trochlear groove (TT\u2013TG) distance. Methods: This retrospective cross-sectional study included 250 patients aged 18\u201338 years who underwent both knee radiography and MRI. Patellar height was assessed using the Insall\u2013Salvati (IS) and modified Insall\u2013Salvati (mIS) ratios on radiographs and MRI, and the Patellotrochlear Index (PTI) on MRI. Associations with fat-pad impingement, chondromalacia grade, and TT\u2013TG abnormality were analyzed using the chi-square or Fisher\u2019s exact test and as odds ratios (ORs) adjusted for age, sex, and imaged side; agreement was assessed with Cohen\u2019s kappa (\u03ba). Results: Patella alta prevalence was 13.2% using IS on radiographs and 10.8% using IS on MRI, but markedly lower with mIS (\u22641.6%). Patella alta was more frequent in patients with Hoffa\u2019s fat-pad impingement (31.1% vs. 5.7% on IS radiography; adjusted OR 8.83, 95% CI 3.82\u201320.45) and advanced chondromalacia (p = 0.025). Agreement was moderate between IS radiography and IS MRI (\u03ba = 0.47, 95% CI 0.33\u20130.61) and between IS MRI and the PTI (\u03ba = 0.43). Conclusions: The prevalence and clinical relevance of patella alta depend strongly on the measurement method. The IS ratio was the most consistent index, but radiography\u2013MRI agreement was moderate rather than high, so the two are not interchangeable. The PTI adds information on trochlear engagement from the same MRI examination. These cross-sectional associations do not establish causation.<\/jats:p>","DOI":"10.3390\/diagnostics16152444","type":"journal-article","created":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T06:17:40Z","timestamp":1785737860000},"page":"2444","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Patella Alta on X-Ray and MRI: Diagnostic Agreement and Clinical Correlations"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-8006-6046","authenticated-orcid":false,"given":"Faten Abdulrahman","family":"Almohideb","sequence":"first","affiliation":[{"name":"Department of Radiology and Medical Imaging, College of Medicine, King Saud University Medical City, King Saud University, Riyadh 11472, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mehad Hussni","family":"Felemban","sequence":"additional","affiliation":[{"name":"Radiology Department, King Faisal Specialist Hospital & Research Centre, Riyadh 11211, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nizar","family":"Al-Nakshabandi","sequence":"additional","affiliation":[{"name":"Department of Radiology and Medical Imaging, College of Medicine, King Saud University Medical City, King Saud University, Riyadh 11472, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mamdouh Saad","family":"Almalki","sequence":"additional","affiliation":[{"name":"Department of Radiology and Medical Imaging, College of Medicine, King Saud University Medical City, King Saud University, Riyadh 11472, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammad","family":"Alfaqih","sequence":"additional","affiliation":[{"name":"Department of Radiology and Medical Imaging, College of Medicine, King Saud University Medical City, King Saud University, Riyadh 11472, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdullah","family":"Alfaqih","sequence":"additional","affiliation":[{"name":"Department of Radiology and Medical Imaging, College of Medicine, King Saud University Medical City, King Saud University, Riyadh 11472, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1697","DOI":"10.1016\/j.joca.2016.05.011","article-title":"The prevalence of patellofemoral osteoarthritis: A systematic review and meta-analysis","volume":"24","author":"Kobayashi","year":"2016","journal-title":"Osteoarthr. 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