{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T23:16:55Z","timestamp":1788218215344,"version":"build-2803163510"},"reference-count":35,"publisher":"Georg Thieme Verlag KG","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Knee Surg"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Robotic Total Knee Arthroplasties (TKAs) have gained popularity over recent years, having been shown to achieve better component alignment than conventional TKAs. However, few studies have compared the different robotic systems. This study was conducted to compare the functional outcomes and implant positioning between a computed tomography (CT) based, semi-active robotic system and a CT-free, passive robotic system. A single-centre propensity score matched retrospective study was conducted comparing 181 CT-based and 113 CT-free cases. Patient reported outcome measures including Oxford Knee Score (OKS), Knee Society Score \u2013 Function (KSS-F), Visual Analogue Scale (VAS) pain score and Passive Range of Motion (ROM) were evaluated preoperatively and at 3 months, 1 year and 2 years postoperatively. Postoperative radiographs including lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), hip knee angle (HKA), femoral flexion and posterior tibial slope (PTS) were also measured. Postoperatively, the CT-based group had better KSS-F scores at 1 year (78.2 vs. 65.9) and 2 years (78 vs. 72), exceeding previously documented MCIDs. Better OKS scores were also demonstrated at 2 years (41.7 vs. 39.8) in the CT-based group. However this does not exceed previously documented MCIDs and is likely clinically insignificant. There was no significant observable difference in VAS pain score and passive ROM. The CT-based group also demonstrate better surgical accuracy, with MPTA (90.0\u00b0 vs. 87.8\u00b0) and HKA (_0.22\u00b0 vs. _2.52\u00b0) closer to planned targets of mechanical alignment. Femoral flexion (3.22\u00b0 \u00b1 0.37\u00b0 vs 0.15\u00b0 \u00b1 0.47\u00b0, p = 0.001) was also closer to the target of 3\u00b0 of flexion. There was no significant difference in posterior tibial slope. We conclude that a CT-based, semi-active robotic system resulted in better functional outcomes and implant positioning than a CT-free passive robotic system.<\/jats:p>","DOI":"10.1055\/a-2939-2755","type":"journal-article","created":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T22:55:05Z","timestamp":1788216905000},"source":"Crossref","is-referenced-by-count":0,"title":["Comparison of Functional Outcomes and Implant Positioning between a CT-based, Semi-active Robotic System and a CT-free Passive Robotic System in Total Knee Arthroplasty"],"prefix":"10.1055","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-7603-0475","authenticated-orcid":false,"given":"Zachary Jieyi","family":"Cheong","sequence":"additional","affiliation":[{"name":"Tan Tock Seng Hospital, Singapore","place":["Singapore"],"department":["Department of Orthopaedic Surgery"]},{"name":"Nanyang Technological University, Singapore","place":["Singapore"],"department":["Lee Kong Chian School of Medicine"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abel Kai Yi","family":"Chen","sequence":"additional","affiliation":[{"name":"Nanyang Technological University, Singapore","place":["Singapore"],"department":["Lee Kong Chian School of Medicine"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zian","family":"Cheng","sequence":"additional","affiliation":[{"name":"Nanyang Technological University, Singapore","place":["Singapore"],"department":["Lee Kong Chian School of Medicine"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Denzel Ming Wei","family":"Lim","sequence":"additional","affiliation":[{"name":"Tan Tock Seng Hospital, Singapore","place":["Singapore"],"department":["Department of Orthopaedic Surgery"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tan Tong","family":"Leng","sequence":"additional","affiliation":[{"name":"Tan Tock Seng Hospital, Singapore","place":["Singapore"],"department":["Department of Orthopaedic Surgery"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lynn","family":"Thwin","sequence":"additional","affiliation":[{"name":"Tan Tock Seng Hospital, Singapore","place":["Singapore"],"department":["Department of Orthopaedic Surgery"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2026,8,31]]},"reference":[{"key":"ref1","doi-asserted-by":"crossref","first-page":"100587","DOI":"10.1016\/j.eclinm.2020.100587","article-title":"Global, regional prevalence, incidence and risk factors of knee osteoarthritis in population-based studies","volume":"29-30","author":"A Cui","year":"2020","journal-title":"EClinicalMedicine"},{"issue":"02","key":"ref2","doi-asserted-by":"crossref","first-page":"192","DOI":"10.1007\/s11420-018-9614-8","article-title":"Patient satisfaction after total knee replacement: a systematic review","volume":"14","author":"C A Kahlenberg","year":"2018","journal-title":"HSS J"},{"key":"ref3","doi-asserted-by":"crossref","first-page":"835","DOI":"10.1186\/s40064-015-1604-4","article-title":"Does malalignment affect revision rate in total knee replacements: a systematic review of the literature","volume":"4","author":"M Hadi","year":"2015","journal-title":"Springerplus"},{"issue":"02","key":"ref4","doi-asserted-by":"crossref","first-page":"e23.00010","DOI":"10.2106\/JBJS.OA.23.00010","article-title":"Radiographic outcomes of robot-assisted versus conventional total knee arthroplasty","volume":"8","author":"A Riantho","year":"2023","journal-title":"JBJS Open Access"},{"issue":"04","key":"ref5","doi-asserted-by":"crossref","first-page":"1132","DOI":"10.1007\/s00167-018-5138-5","article-title":"Robotic-arm assisted total knee arthroplasty has a learning curve of seven cases for integration into the surgical workflow but no learning curve effect for accuracy of implant positioning","volume":"27","author":"B Kayani","year":"2019","journal-title":"Knee Surg Sports Traumatol Arthrosc"},{"issue":"06","key":"ref6","doi-asserted-by":"crossref","first-page":"1075","DOI":"10.1007\/s00167-011-1695-6","article-title":"Alignment outcomes in navigated total knee arthroplasty: a meta-analysis","volume":"20","author":"Y Fu","year":"2012","journal-title":"Knee Surg Sports Traumatol Arthrosc"},{"issue":"07","key":"ref7","doi-asserted-by":"crossref","first-page":"1307","DOI":"10.1007\/s00167-011-1588-8","article-title":"Does computer-assisted surgery improve postoperative leg alignment and implant positioning following total knee arthroplasty? 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