{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T00:15:49Z","timestamp":1790640949255,"version":"4.1.0"},"reference-count":55,"publisher":"Georg Thieme Verlag KG","issue":"09","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Rofo"],"published-print":{"date-parts":[[2021,9]]},"abstract":"<jats:p>\n            Background\u2002Throughout the literature, patellofemoral instability (PI) is defined as an increased risk of re-\/luxation of the patella within the patellofemoral joint (PFJ). In most patients it is caused by traumatic patella luxation or the existence of a range of predisposing anatomic risk factors leading to an unphysiological movement sequence within the PFJ also known as patellofemoral maltracking. In order to provide an individualized therapy approach, clinical and radiological evaluation of those risk factors of variable magnitude becomes essential. Diagnostic imaging such as magnetic resonance imaging (MRI), plain radiography, and computed tomography (CT) are straightforward diagnostic tools in terms of evaluation and treatment of PI.<\/jats:p><jats:p>\n            Method\u2002In this review we performed a precise analysis of today\u2019s literature concerning the radiological evaluation of anatomic risk factors leading to PI. The purpose of the review is to present a logical compilation of the different anatomical risk factors causing PI and provide a straight overview of valuable radiological imaging techniques.<\/jats:p><jats:p>\n            Results and Conclusion\u2002PI is frequently based on a multifactorial disposition. The most relevant predisposing risk factors are trochlea dysplasia, rupture of the medial patellofemoral ligament (MPFL), patella alta, abnormal tibial tubercle to trochlea groove distance (TT-TG), femoral torsion deformities, and genu valgum. Although plain X-rays may provide basic diagnostic value, cross-sectional imaging (MRI, CT) is the standard radiological tool in terms of evaluation and detection of severity of predisposing anatomic variants leading to PI.<\/jats:p><jats:p>\n            Key Points:\u2002<\/jats:p><jats:p>\n            Citation Format\n          <\/jats:p>","DOI":"10.1055\/a-1348-2122","type":"journal-article","created":{"date-parts":[[2021,3,27]],"date-time":"2021-03-27T23:38:50Z","timestamp":1616888330000},"page":"1019-1033","source":"Crossref","is-referenced-by-count":15,"title":["Diagnostic Imaging of Patellofemoral Instability"],"prefix":"10.1055","volume":"193","author":[{"given":"Kai-Jonathan","family":"Maas","sequence":"additional","affiliation":[{"name":"Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Malte Lennart","family":"Warncke","sequence":"additional","affiliation":[{"name":"Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miriam","family":"Leiderer","sequence":"additional","affiliation":[{"name":"Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthias","family":"Krause","sequence":"additional","affiliation":[{"name":"Department Trauma Surgery and Orthopedics, UKE, Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tobias","family":"Dust","sequence":"additional","affiliation":[{"name":"Department Trauma Surgery and Orthopedics, UKE, Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jannik","family":"Frings","sequence":"additional","affiliation":[{"name":"Department Trauma Surgery and Orthopedics, UKE, Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karl-Heinz","family":"Frosch","sequence":"additional","affiliation":[{"name":"Department Trauma Surgery and Orthopedics, UKE, Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gerhard","family":"Adam","sequence":"additional","affiliation":[{"name":"Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frank Oliver Gerhard","family":"Henes","sequence":"additional","affiliation":[{"name":"Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2021,3,27]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"485","DOI":"10.1007\/s00402-015-2381-9","article-title":"A new classification system of patellar instability and patellar maltracking","volume":"136","author":"K H Frosch","year":"2016","journal-title":"Arch Orthop Trauma Surg"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"2747","DOI":"10.1007\/s00167-013-2637-2","article-title":"Long-term clinical and radiographic outcome of patello-femoral realignment procedures: a minimum of 15-year follow-up","volume":"22","author":"G Vivod","year":"2013","journal-title":"Knee Surg Sports Traumatol Arthrosc"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"472","DOI":"10.1177\/03635465000280040601","article-title":"Characteristics of Patients with Primary Acute Lateral Patellar Dislocation and Their Recovery within the First 6 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