{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,12]],"date-time":"2026-09-12T06:25:20Z","timestamp":1789194320315,"version":"build-2803163510"},"reference-count":40,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2023,12,31]],"date-time":"2023-12-31T00:00:00Z","timestamp":1703980800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Knee surg. sports traumatol. arthrosc."],"published-print":{"date-parts":[[2024,1]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Purpose<\/jats:title><jats:p>Restricted kinematic alignment (rKA) is a modified technique of kinematically aligned total knee arthroplasty (TKA) within a safe alignment range for long\u2010term implant survivorship. The purpose of this study was to clarify (1) the distribution of functional knee phenotypes in patients who underwent TKA in Japan and (2) whether the application of this classification results in anatomically neutral alignment after rKA TKA.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>Overall, 114 TKA surgeries (mechanical alignment [MA]: 49; rKA: 65) were performed. The joint line orientation angle (JLOA), hip\u2013knee\u2013ankle angle (HKA), femoral mechanical angle (FMA)\u00a0and tibial mechanical angle (TMA) were obtained. The knees were categorized using a functional knee phenotype classification. Clinical evaluations, including the Knee Injury and Osteoarthritis Outcome, 12\u2010question Forgotten Joint\u00a0and Oxford Knee Scores, were performed 3 years postoperatively. Between\u2010group comparisons were made.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The most common preoperative functional knee phenotype was VAR<jats:sub>HKA<\/jats:sub>3\u00b0\u2009+\u2009NEU<jats:sub>FMA<\/jats:sub>0\u00b0\u2009+\u2009VAR<jats:sub>TMA<\/jats:sub>3\u00b0 (11.4%). In the preoperative population, 51 knees (44.7%) had VAR<jats:sub>FMA<\/jats:sub>\u2009\u2265\u20093\u00b0. Postoperatively, the most common functional knee phenotype was NEU<jats:sub>HKA<\/jats:sub>0\u00b0\u2009+\u2009VAR<jats:sub>FMA<\/jats:sub>3\u00b0\u2009+\u2009VAL<jats:sub>TMA<\/jats:sub>3\u00b0 (14 knees, 28.6%) in the MA and NEU<jats:sub>HKA<\/jats:sub>0\u00b0\u2009+\u2009NEU<jats:sub>FMA<\/jats:sub>0\u00b0\u2009+\u2009NEU<jats:sub>TMA<\/jats:sub>0\u00b0 in the rKA group. The percentage of postoperative JLOA within \u00b13\u00b0 from the floor was 27% and 72% in the MA and rKA groups, respectively (<jats:italic>p<\/jats:italic>\u2009&lt;\u20090.001). The functional knee phenotype after rKA TKA was neutrally reproduced, and the joint line was more parallel to the ground in the standing position than that of MA. Between\u2010group differences in clinical outcomes were not significant.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>The application of functional knee phenotyping to knee osteoarthritis in Japan suggested the presence of racial morphological characteristics. This classification could help better visualize potential femoral varus, contributing to protocol deviation in applying restricted KA TKA.<\/jats:p><\/jats:sec><jats:sec><jats:title>Level of Evidence<\/jats:title><jats:p>Level IV.<\/jats:p><\/jats:sec>","DOI":"10.1002\/ksa.12028","type":"journal-article","created":{"date-parts":[[2024,1,1]],"date-time":"2024-01-01T02:48:15Z","timestamp":1704077295000},"page":"103-115","source":"Crossref","is-referenced-by-count":15,"title":["Functional knee phenotypes: A helpful classification tool for visualizing potential femoral varus in restricted kinematic alignment total knee arthroplasty in Japan"],"prefix":"10.1002","volume":"32","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2297-0852","authenticated-orcid":false,"given":"Takashi","family":"Kobayashi","sequence":"first","affiliation":[{"name":"Department of Orthopedic Surgery Yugawara Hospital Yugawara Kanagawa Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kohei","family":"Kawaguchi","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Faculty of Medicine The University of Tokyo Bunkyo City Tokyo Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1246-9055","authenticated-orcid":false,"given":"Kazumi","family":"Goto","sequence":"additional","affiliation":[{"name":"Department of Sports Orthopedics Surgery Kanto Rosai Hospital Kawasaki Kanagawa Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hayata","family":"Suzuki","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery Yugawara Hospital Yugawara Kanagawa Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masayoshi","family":"Otsu","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery Yugawara Hospital Yugawara Kanagawa Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazuhiko","family":"Michishita","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery Yugawara Hospital Yugawara Kanagawa Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2023,12,31]]},"reference":[{"key":"e_1_2_11_2_1","doi-asserted-by":"publisher","DOI":"10.2106\/JBJS.E.00440"},{"key":"e_1_2_11_3_1","doi-asserted-by":"publisher","DOI":"10.2106\/JBJS.H.01566"},{"key":"e_1_2_11_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.otsr.2019.07.005"},{"key":"e_1_2_11_5_1","doi-asserted-by":"publisher","DOI":"10.1302\/2058-5241.3.170021"},{"key":"e_1_2_11_6_1","doi-asserted-by":"publisher","DOI":"10.1302\/2633-1462.35.BJO-2022-0021.R2"},{"key":"e_1_2_11_7_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12891-023-06448-0"},{"key":"e_1_2_11_8_1","doi-asserted-by":"publisher","DOI":"10.1302\/2046-3758.61.BJR-2016-0090.R1"},{"key":"e_1_2_11_9_1","doi-asserted-by":"publisher","DOI":"10.3389\/fsurg.2021.697020"},{"key":"e_1_2_11_10_1","doi-asserted-by":"publisher","DOI":"10.1302\/0301-620X.73B5.1894655"},{"key":"e_1_2_11_11_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00167-021-06811-5"},{"key":"e_1_2_11_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.knee.2022.02.008"},{"key":"e_1_2_11_13_1","doi-asserted-by":"publisher","DOI":"10.1055\/s-0042-1742645"},{"key":"e_1_2_11_14_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00264-015-2733-7"},{"key":"e_1_2_11_15_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00167-016-3995-3"},{"key":"e_1_2_11_16_1","doi-asserted-by":"publisher","DOI":"10.1007\/s11999-011-1936-5"},{"key":"e_1_2_11_17_1","doi-asserted-by":"publisher","DOI":"10.1007\/s11999-013-2898-6"},{"key":"e_1_2_11_18_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00167-019-05509-z"},{"key":"e_1_2_11_19_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00167-021-06687-5"},{"key":"e_1_2_11_20_1","doi-asserted-by":"publisher","DOI":"10.1097\/00003086-200403000-00030"},{"key":"e_1_2_11_21_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.arth.2017.02.028"},{"key":"e_1_2_11_22_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.otsr.2015.11.010"},{"key":"e_1_2_11_23_1","doi-asserted-by":"publisher","DOI":"10.1186\/s40634-023-00606-y"},{"key":"e_1_2_11_24_1","doi-asserted-by":"publisher","DOI":"10.1177\/2309499016684754"},{"key":"e_1_2_11_25_1","unstructured":"KOOS\/KOOS\u201012 Questionnaries. 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