{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T05:11:27Z","timestamp":1778303487776,"version":"3.51.4"},"reference-count":25,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T00:00:00Z","timestamp":1778284800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T00:00:00Z","timestamp":1778284800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Arch Orthop Trauma Surg"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Robotic-assisted unicompartmental knee arthroplasty (RA-UKA) may improve implant positioning, but its impact on index-hospitalization length of stay (LOS), billed charges, and early inpatient outcomes in routine practice remains unclear.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Using the National Inpatient Sample (2016\u20132022), we identified primary medial UKA for osteoarthritis. RA-UKA was defined by ICD-10-PCS robotic-assisted lower-extremity procedure codes. Primary outcomes were prolonged hospitalization (LOS\u2009\u2265\u2009the 75th percentile, \u2265 2 days), high-charge admission (total hospital charges [TOTCHG]\u2009\u2265\u2009the 75th percentile, \u2265 $72,321), and in-hospital mortality. We performed univariable comparisons and multivariable logistic regression adjusting for demographics, payer, admission type, hospital teaching status, comorbidities, and calendar year fixed effects (YEAR 2016\u20132022) using the unweighted NIS discharge sample.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Among 7,154 UKAs, 1,297 (18.1%) were RA-UKA and 5,857 (81.9%) were C-UKA. Median LOS was 1\u00a0day (IQR 1\u20132) in both groups; however, prolonged hospitalization (LOS\u2009\u2265\u20092 days) occurred less frequently in RA-UKA (412\/1,297 [30.7%] vs. 2,162\/5,857 [37.2%];\n                      <jats:italic>P<\/jats:italic>\n                      \u2009&lt;\u20090.001). In adjusted analyses including YEAR fixed effects, RA-UKA was associated with lower odds of prolonged hospitalization (aOR 0.750, 95% CI 0.647\u20130.870;\n                      <jats:italic>P<\/jats:italic>\n                      \u2009&lt;\u20090.001) and was not associated with high-charge admission (TOTCHG \u2265 $72,321; aOR 1.007, 95% CI 0.855\u20131.186;\n                      <jats:italic>P<\/jats:italic>\n                      \u2009=\u20090.993). In-hospital mortality and other inpatient complications were rare.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>RA-UKA was associated with lower odds of prolonged hospitalization (LOS\u2009\u2265\u20092 days) and no higher odds of a high-charge admission (billed charges, TOTCHG) during the index hospitalization. Findings apply to the index hospitalization only.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00402-026-06336-x","type":"journal-article","created":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T04:29:57Z","timestamp":1778300997000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Robotic-assisted unicompartmental knee arthroplasty is associated with lower odds of prolonged hospitalization and no higher odds of high-charge admission during the index hospitalization"],"prefix":"10.1007","volume":"146","author":[{"given":"Qiaoqiao","family":"Sun","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ying","family":"Xu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaodan","family":"Hong","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ming","family":"Dai","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianping","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hao","family":"Xie","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zicai","family":"Fu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2026,5,9]]},"reference":[{"issue":"12","key":"6336_CR1","doi-asserted-by":"publisher","first-page":"3281","DOI":"10.1002\/ksa.12353","volume":"32","author":"D Maman","year":"2024","unstructured":"Maman D, Laver L, Becker R, Takrori LA, Mahamid A, Finkel B et al (2024) Trends and epidemiology in robotic-assisted total knee arthroplasty: reduced complications and shorter hospital stays. 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