{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T10:26:55Z","timestamp":1787308015622,"version":"build-2736575974"},"reference-count":18,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T00:00:00Z","timestamp":1787270400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100009563","name":"Fundaci\u00f3n para la Formaci\u00f3n e Investigaci\u00f3n Sanitarias de la Regi\u00f3n de Murcia","doi-asserted-by":"publisher","award":["FUO-24-192"],"award-info":[{"award-number":["FUO-24-192"]}],"id":[{"id":"10.13039\/501100009563","id-type":"DOI","asserted-by":"publisher"}]},{"award":["FUO-24-192"],"award-info":[{"award-number":["FUO-24-192"]}],"id":[{"id":"https:\/\/ror.org\/05m5has32","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>A clinical observation of a previously asymptomatic native knee developing a relevant coronal alignment change after total hip arthroplasty (THA) motivated this research. This raised the question of whether the native knee morphology could influence the response to biomechanical changes elsewhere in the lower limb. First, we developed a simplified finite element model incorporating the Coronal Plane Alignment of the Knee (CPAK) classification. We developed a simplified model of the knee, where we represented the lateral distal femoral angle (LDFA) by physically rotating the femur, and to avoid remodeling the tibia coronal plane for each simulation, we represented the medial proximal tibial angle (MPTA) by adjusting the neutral angle of the joint (the angle at which the joint generates no reaction force). This allowed for quick parametric iteration over the CPAK input space, showing which type of knees were more vulnerable to extreme valgus (CPAK III) and varus (CPAK VII) due to their morphology. The simplicity of this model will also enable users with less technical expertise to quickly obtain insights into specific knee morphologies, without requiring deep knowledge about finite element modeling. This existing model lays the foundation for later work, with a deeper look into how changes to hip morphology build on the pre-existing tendencies to varus and valgus.<\/jats:p>","DOI":"10.3390\/bioengineering13080946","type":"journal-article","created":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T09:31:59Z","timestamp":1787304719000},"page":"946","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Simplified Model of the Knee for Coronal Plane Alignment of the Knee Simulation"],"prefix":"10.3390","volume":"13","author":[{"given":"C\u00e9sar","family":"Rodr\u00edguez Pereira","sequence":"first","affiliation":[{"name":"Instituto de Ciencias y Tecnolog\u00edas Espaciales de Asturias, University of Oviedo, 33004 Oviedo, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9548-7322","authenticated-orcid":false,"given":"Javier Gracia","family":"Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Instituto de Ciencias y Tecnolog\u00edas Espaciales de Asturias, University of Oviedo, 33004 Oviedo, Spain"},{"name":"Department of Manufacturing and Construction Engineering, University of Oviedo, 33203 Gij\u00f3n, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7052-2811","authenticated-orcid":false,"given":"Fernando S\u00e1nchez","family":"Lasheras","sequence":"additional","affiliation":[{"name":"Instituto de Ciencias y Tecnolog\u00edas Espaciales de Asturias, University of Oviedo, 33004 Oviedo, Spain"},{"name":"Department of Mathematics, University of Oviedo, 33007 Oviedo, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9345-5113","authenticated-orcid":false,"given":"Francisco Javier","family":"Iglesias Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Instituto de Ciencias y Tecnolog\u00edas Espaciales de Asturias, University of Oviedo, 33004 Oviedo, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2366-2317","authenticated-orcid":false,"given":"Antonio","family":"Murcia Asensio","sequence":"additional","affiliation":[{"name":"Hospital General Universitario Reina Sof\u00eda, Avenida Intendente Jorge Palacios 1, 30003 Murcia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"198","DOI":"10.1007\/s12045-015-0170-y","article-title":"Ed Lorenz: Father of the \u2018butterfly effect\u2019","volume":"20","author":"Ambika","year":"2015","journal-title":"Resonance"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"405","DOI":"10.1002\/jor.1100100314","article-title":"Role of loads and prosthesis material properties on the mechanics of the proximal femur after total hip arthroplasty","volume":"10","author":"Cheal","year":"1992","journal-title":"J. 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