{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T06:29:09Z","timestamp":1781764149690,"version":"3.54.5"},"reference-count":27,"publisher":"Georg Thieme Verlag KG","issue":"09","funder":[{"DOI":"10.13039\/100006108","name":"National Center for Advancing Translational Sciences","doi-asserted-by":"crossref","award":["UL1TR002553"],"award-info":[{"award-number":["UL1TR002553"]}],"id":[{"id":"10.13039\/100006108","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Knee Surg"],"published-print":{"date-parts":[[2025,7]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Varus-producing distal femoral osteotomy (DFO) is an established procedure to correct genu valgum in patients with osteoarthritis and gait abnormalities. DFO has also been proposed for the treatment of patellar instability in patients with valgus alignment. However, it is not known how DFO affects parameters associated with patellar instability. This study evaluated radiographic changes after DFO with variable degrees of correction on six cadaveric knees, with the hypothesis that improving mechanical alignment would improve radiographic parameters related to patellar instability. Controlled laboratory is the study design. Six lower-limb cadaveric specimens were obtained after approval by the Institutional Review Board. A lateral opening wedge DFO was performed on each specimen with correction blocks of 6, 10, and 14\u2009mm. The mechanical axis, tibiofemoral angle (mTFA), distal femoral angle (mDFA), Caton Deschamps index (CDI), insall salvati index (ISI), tibial tubercle to trochlear groove distance (TT-TG), and patellofemoral congruence angle (PFCA) were measured on computed tomography (CT) scans at baseline and after each correction block. At baseline, a mean varus alignment of the limbs was observed (mTFA: 2.7\u2009\u00b1\u20092.8\u2009degrees, mDFA: 87.6\u2009\u00b1\u20091.0\u2009degrees). The baseline patellar height was normal (CDI: 0.9\u2009\u00b1\u20090.2, ISI: 1.0\u2009\u00b1\u20090.1). Statistically significant decreases in mechanical axis and TT-TG distance and increases in mDFA and mFTA were found with increasing block size. The TT-TG distance was decreased by \u22121.6\u2009mm (95% confidence interval [CI]: \u22122.27 to \u22120.86), \u22123.8\u2009mm (95% CI: \u22124.8 to \u22122.8), and \u22124.0\u2009mm (95% CI: \u22125.4 to \u22122.7) with a 6, 10, and 14\u2009mm block, respectively. No differences were observed in patellar height when measured with CDI or ISI after any block size. In a cadaveric model, DFO significantly affects the mechanical axis and TT-TG distance. Specifically, this study found a mean decrease in TT-TG of \u22123.8\u2009mm when performing a 10\u2009mm opening wedge osteotomy. No changes in patellar height were observed.<\/jats:p>","DOI":"10.1055\/a-2542-2639","type":"journal-article","created":{"date-parts":[[2025,2,20]],"date-time":"2025-02-20T23:53:26Z","timestamp":1740095606000},"page":"463-468","source":"Crossref","is-referenced-by-count":2,"title":["Varus Producing Distal Femur Osteotomy Alters Radiographic Measurements Related to Patellofemoral Instability: A Cadaver Study"],"prefix":"10.1055","volume":"38","author":[{"given":"Elizabeth C.","family":"Bond","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Duke University School of Medicine, Durham, North Carolina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Grant","family":"Cochran","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Duke University School of Medicine, Durham, North Carolina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-5805-1971","authenticated-orcid":false,"given":"Clark H.","family":"Bulleit","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Duke University School of Medicine, Durham, North Carolina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emily","family":"Poehlein","sequence":"additional","affiliation":[{"name":"Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, North Carolina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cynthia L.","family":"Green","sequence":"additional","affiliation":[{"name":"Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, North Carolina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jocelyn R.","family":"Wittstein","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Duke University School of Medicine, Durham, North Carolina"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2025,4,7]]},"reference":[{"issue":"05","key":"ref1","doi-asserted-by":"crossref","first-page":"1114","DOI":"10.1177\/0363546503260788","article-title":"Epidemiology and natural history of acute patellar dislocation","volume":"32","author":"D C Fithian","year":"2004","journal-title":"Am J Sports Med"},{"issue":"05","key":"ref2","doi-asserted-by":"crossref","first-page":"2325967121993179","DOI":"10.1177\/2325967121993179","article-title":"Radiologic measurements in the assessment of patellar instability: a systematic review and meta-analysis","volume":"9","author":"A E White","year":"2021","journal-title":"Orthop J Sports Med"},{"issue":"04","key":"ref3","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1055\/s-0035-1544973","article-title":"Tibial tubercle osteotomy: indication and techniques","volume":"28","author":"B Grawe","year":"2015","journal-title":"J Knee Surg"},{"issue":"02","key":"ref4","doi-asserted-by":"crossref","first-page":"652","DOI":"10.1007\/s00167-018-5212-z","article-title":"Derotational osteotomy at the distal femur is effective to treat patients with patellar instability","volume":"27","author":"F B Imhoff","year":"2019","journal-title":"Knee Surg Sports Traumatol Arthrosc"},{"issue":"07","key":"ref5","doi-asserted-by":"crossref","first-page":"103035","DOI":"10.1016\/j.otsr.2021.103035","article-title":"Complications and outcomes of trochleoplasty for patellofemoral instability: a systematic review and meta-analysis of 1000 trochleoplasties","volume":"107","author":"J T Leclerc","year":"2021","journal-title":"Orthop Traumatol Surg Res"},{"issue":"06","key":"ref6","doi-asserted-by":"crossref","first-page":"1171","DOI":"10.1016\/j.knee.2019.11.007","article-title":"Current concepts in the surgical management of patellar 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