{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T12:57:47Z","timestamp":1779109067446,"version":"3.51.4"},"reference-count":33,"publisher":"Public Library of Science (PLoS)","issue":"3","license":[{"start":{"date-parts":[[2025,3,14]],"date-time":"2025-03-14T00:00:00Z","timestamp":1741910400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec014\">\n<jats:title>Introduction<\/jats:title>\n<jats:p>The impact of medial unicompartmental knee arthroplasty (MUKA) on ankle alignment is not well-studied. This study aims to investigate the changes in ankle alignment following MUKA and identify the influencing factors.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec015\">\n<jats:title>Materials and Methods<\/jats:title>\n<jats:p>A retrospective analysis included 175 patients undergoing MUKA between 2018 and 2020. Patients were categorized into varus (n =\u2009 113) or valgus (n =\u2009 62) ankle groups based on preoperative ankle deformities. Preoperative and postoperative full-length standing radiographs were used for radiographic measurements.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec016\">\n<jats:title>Results<\/jats:title>\n<jats:p>Following MUKA, significant differences in the change in tibial plafond-talus angle (PTA) were observed between the groups, with the varus ankle group showing a change of -0.71 \u00b1\u2009 0.82\u00b0 and the valgus ankle group showing a change of 0.08 \u00b1\u2009 0.94\u00b0 (p &lt;\u2009 0.001). In the varus ankle group, the tibial plafond-ground angle (PGA) increased from -3.65 \u00b1\u2009 4.22\u00b0 preoperatively to -0.51 \u00b1\u2009 4.52\u00b0 postoperatively (p &lt;\u2009 0.001), talus-ground angle (TGA) increased from -5.28 \u00b1\u2009 4.32\u00b0 to -1.32 \u00b1\u2009 4.74\u00b0 (p &lt;\u2009 0.001), and PTA decreased from 1.52 \u00b1\u2009 1.04\u00b0 to 0.81 \u00b1\u2009 1.12\u00b0 (p &lt;\u2009 0.001). In the valgus ankle group, PGA increased from -5.44 \u00b1\u2009 4.39\u00b0 to -1.43 \u00b1\u2009 4.63\u00b0 (p &lt;\u2009 0.001) and TGA increased from -4.55 \u00b1\u2009 4.24\u00b0 to -0.59 \u00b1\u2009 4.47\u00b0 (p &lt;\u2009 0.001), but PTA did not show a significant change. Ankle alignment change significantly correlated with preoperative joint line convergence angle (JLCA), preoperative medial proximal tibial angle (MPTA), preoperative PGA, preoperative TGA, preoperative PTA, hip-knee-ankle angle (HKA) changes, and bearing thickness.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec017\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>MUKA significantly corrects the majority of ankle alignment towards a more neutral position. The extent of ankle alignment correction is influenced by preoperative knee and ankle joint deformities, as well as the degree of knee alignment correction.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0318677","type":"journal-article","created":{"date-parts":[[2025,3,14]],"date-time":"2025-03-14T17:23:21Z","timestamp":1741973001000},"page":"e0318677","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":1,"title":["Factors influencing ankle alignment changes following medial unicompartmental knee arthroplasty: Preoperative knee and ankle deformities and extent of knee alignment 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