{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T14:47:26Z","timestamp":1787755646783,"version":"build-2784847793"},"reference-count":32,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"1","license":[{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"abstract":"<jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>Unicompartmental knee arthroplasty (UKA) is an effective treatment for unicompartmental end-stage knee arthritis. Simultaneous bilateral UKAs for patients with bilateral knee arthritis can reduce costs, number of anesthetics, and overall rehabilitation time. It is unknown how the long-term outcomes of unilateral and simultaneous bilateral UKAs compare.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>In total, 1,939 unilateral and 1,939 simultaneous bilateral medial mobile-bearing UKAs (n = 3,878) from the National Joint Registry were propensity score matched. Kaplan-Meier and Cox regression were used to compare implant survival, revision indications, and mortality.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>The 10-year implant survival in the simultaneous bilateral group was 92% (95% confidence interval [CI] 90-94) and in the unilateral group was 90% (95% CI 88-92). The simultaneous bilateral group had a lower revision risk (hazard ratio [HR] 0.73, p = 0.01). Revisions for pain were lower in the bilateral group (0.5% vs. 1.2%, p = 0.01). There were no differences in patient mortality. Subgroup analyses found similar trends in 10-year implant survival and revision risk with both cementless (simultaneous bilateral 98% CI 95-99; unilateral 95% CI 91-98; HR 0.66, p = 0.27) and cemented fixation (simultaneous bilateral 91% CI 89-93; unilateral 90% CI 88%-92%; HR 0.85, p = 0.28).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions:<\/jats:title>\n                    <jats:p>Simultaneous bilateral UKAs had better 10-year implant survival and similar mortality to compared with single-unilateral UKAs. For patients with severe symptomatic bilateral unicompartmental knee osteoarthritis, simultaneous bilateral UKAs could be considered to be a safe and effective procedure, particularly as only one operation and postoperative recovery is required.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Level of Evidence:<\/jats:title>\n                    <jats:p>\n                      <jats:underline>Level IV<\/jats:underline>\n                      . See Instructions for Authors for a complete description of levels of evidence.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.2106\/jbjs.oa.25.00292","type":"journal-article","created":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T19:02:25Z","timestamp":1770145345000},"update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":0,"title":["A Comparison of the Outcomes of Simultaneous Bilateral and Unilateral Mobile-Bearing Unicompartmental Knee Arthroplasties"],"prefix":"10.2106","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2146-8601","authenticated-orcid":false,"given":"Hasan Raza","family":"Mohammad","sequence":"first","affiliation":[{"name":"Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Nuffield Orthopaedic Centre, Oxford, United Kingdom"},{"name":"Barts Bone & Joint Health, Blizard Institute, Barts and The London School of 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