Forgotten Joint Score" one year after robot-assisted total knee arthroplasty

Forgotten Joint Score" one year after robot-assisted total knee arthroplasty | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Forgotten Joint Score" one year after robot-assisted total knee arthroplasty JOAO PAULO GUERREIRO, CAMILA Pinheiro Bortolossi de Souza, CARLOS AUGUSTO Ferraresi Sampaio, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8790936/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 23 Mar, 2026 Read the published version in Journal of Robotic Surgery → Version 1 posted 9 You are reading this latest preprint version Abstract Objective: The objective of this study was to analyze the postoperative results of patients who underwent cTKA compared to those who underwent robot-assisted total knee arthroplasty (raTKA). Methods: A retrospective analysis was conducted on patients who underwent primary TKA. Patients were classified into two groups based on prosthesis type. Functional outcomes were assessed using the Forgotten Joint Score (FJS). Statistical analysis included multiple linear regression to identify predictors of joint awareness. Results: A total of 181 patients were analyzed (raTKA group: n = 90; cTKA group: n = 91). FJS scores were significantly higher in the raTKA group (72,5 [54.1–100]) than in the cTKA group (61.8 [39.6–91.7]; p = 0.004). Regression analysis identified the male sex (coef. = 11.50, p = 0.005) as a positive predictor of FJS, while cTKA group was associated with lower scores (coef. = -9.09, p = 0.026). Body mass index showed no significant association with FJS (coef. = 0.65, p = 0.214). Conclusion: Surgery type and sex influence joint awareness post-TKA. Male patients and raTKA group demonstrating superior functional perception. These findings underscore the importance of prosthesis selection in optimizing postoperative outcomes. Osteoarthritis Knee Conventional arthroplasty Arthroplasty with robotic arm Figures Figure 1 Figure 2 INTRODUCTION Despite significant advances in prosthesis design, surgical techniques, and postoperative rehabilitation protocols over the past two decades, between 10% and 20% of patients remain dissatisfied after total knee arthroplasty using the conventional technique (TKA) ( 1 ). Widely cited factors related to this dissatisfaction include inaccurate prosthesis positioning and suboptimal restoration of limb alignment ( 2 ). Therefore, robotic technology has been incorporated into knee arthroplasty surgery to help surgeons achieve greater precision in bone cutting, restore mechanical alignment and proper implant positioning, which are important factors in increasing the longevity of the prosthesis and improving functional outcomes ( 3 ). Recent and initial evidence indicate that robotic surgery has provided better clinical outcomes, a lower incidence of complications, and more accurate postoperative limb alignment ( 1 , 3 ). The objective of this study was to analyze the postoperative results of patients who underwent cTKA compared to those who underwent robot-assisted total knee arthroplasty (raTKA). MATERIALS AND METHODS This study was approved by the Ethics Committee of the Pontifical Catholic University of Paraná, under opinion 6.903.444. All patients signed informed consent for the use of their data in this study. The study included patients aged 18 years or older, of both sexes, who underwent primary total knee arthroplasty performed by same knee surgery team. Exclusion criteria included patients who underwent revision arthroplasty, those under 18 years of age, individuals whose medical records were inaccessible, patients who were lost to follow-up during the study period, refused to participate in the study, and, according to the established criteria ( 2 ), patients who answered less than 8 of the 12 questions on the assessment questionnaire were excluded. This was a retrospective cohort study. Between October 2022 and September 2023, all patients who underwent TKA, both by the traditional method and robot-assisted, were selected. The surgical procedures were performed by four orthopedic surgeons, each with more than 10 years of experience in arthroplasty. The data were extracted from electronic medical records and systematically compiled into a standardized database. Patients were classified into two groups according to the type of TKA performed: one group of patients, raTKA, who underwent robotic-assisted total knee arthroplasty (ROSA® Knee System, Zimmer, Warsaw, IN, USA), and another group, cTKA, consisting of those who underwent conventional total knee arthroplasty. All patients received the same prosthesis models (NEXGEN®, Zimmer, Warsaw, IN, USA). After classification of the patients, those eligible for participation were contacted by evaluators blinded to the type of surgery performed to agree to the informed consent form, and if so, an adapted questionnaire was administered to assess clinical and functional outcomes. In addition functional outcomes were assessed using the Forgotten Joint Score (FJS), a validated instrument for hip and knee arthroplasty, culturally adapted to Portuguese ( 4 ), which evaluates joint awareness in daily activities and the patient’s perceived knee function and prosthesis integration. The outcomes analyzed included the results of the FJS-12, pain complaints, return to physical activities, and satisfaction with the surgery. All assessments were performed at least one year after the surgical procedure. The Shapiro-Wilk test was used to verify the normality of numerical data. Qualitative data were represented by frequency and analyzed using the t-test or Mann-Whitney test, according to the normality result. Categorical data were represented by mean (SD) or median (IQR) and analyzed using Fisher's exact test. Multivariate linear regression analysis was also performed to evaluate the factors associated with the outcome. All statistical analyses were performed using STATA v.16 software (Stata Corporation LLC, College Station, USA), with a significance level of 5% for all tests applied. RESULTS All 222 patients who underwent surgery during the study period were selected, and 186 agreed to participate in the study and were initially included. Of these, 26 refused to answer the questionnaires, 9 were lost to follow-up, and there was 1 death during follow-up. Of the 186 patients recruited, 92 were part of the group that underwent cTAH, and 94 were part of the group that underwent rTAH. Of the 26 patients who refused to participate in the study, 17 were part of the conventional group, and 9 were part of the robot-assisted group. The patient who died belonged to the cTAH group (Fig. 1). According to the previously established questionnaire validity criteria, five patients were subsequently excluded from the analysis: four from the raTKA group, three due to incomplete responses and one due to postoperative infection, and one from the cTKA group due to an insufficient number of responses. In the final analysis, therefore, 181 patients were included, totaling 91 patients in the cTKA group and 90 who underwent raTKA. The mean age of the raTKA group was 68.1 ± 8.9, while that of the cTKA group was 68.6 ± 9.0 (Table 1). No statistically significant difference was observed between the groups in terms of gender distribution. However, the body mass index (BMI) was significantly higher in the raTKA group compared to the cTKA group, with a mean of 29.4 (27.2–32.1) versus 28.4 (25.0–30.8), respectively (p = 0.039) (Table 1). Table 1 Demographic and Clinical Characteristics of the Patients Characteristic ATJr (n = 90) ATJc (n = 91) p value Age, mean ± SD 68.1 ± 8.9 68.6 ± 9.0 0.637 Male sex, n (%) 47 (52.2) 41 (45.1) 0.416 BMI, median (IQR) 29.4 (27.2–32.1) 28.0 (25.0–30.8) 0.039 ATJr = robotic-assisted total knee arthroplasty; ATJc = conventional total knee arthroplasty; n = number of patients; BMI = body mass index; IQR = interquartile range. As shown in Fig. 2, patient satisfaction with surgery (83.9% vs. 88.5%; p = 0.349) did not differ significantly. The FJS showed significantly higher median scores in the raTKA group compared to the cTKA group (72.5 [54.1–100] vs. 61.8 [39.6–91.7]; p = 0.004) (Table 2 and Fig. 2). Table 2 Patient-Reported Outcomes Characteristic ATJr (n = 90) ATJc (n = 91) p value Satisfaction, n (%) 92 (88.5) 78 (83.9) 0.349 Return to physical activity, n (%) 40 (43.0) 48 (46.1) 0.657 Pain, n (%) 29 (27.8) 34 (37.4) 0.326 FJS, median (IQR) 72.5 (54.1–100) 61.8 (39.6–91.7) 0.004 ATJr = robotic-assisted total knee arthroplasty; ATJc = conventional total knee arthroplasty; n = number of patients; FJS = Forgotten Joint Score; IQR = interquartile range. The occurrence of pain was also evaluated between the groups, with 37.4% of patients in the control group reporting this complaint, compared to 27.8% in the robotic group. However, this difference did not reach statistical significance (p = 0.326) (Table 2). The analysis of return to physical activity revealed that, among the patients evaluated, 43.0% in the raTKA group and 46.1% in the cTKA group reported never or rarely remembering the artificial joint while practicing their favorite sport. The difference between the groups, however, was not statistically significant, with a p-value of 0.657, indicating that the return to physical activity and perception of the prosthesis did not vary significantly between the two surgical methods (Table 2). A multiple linear regression analysis was performed with FJS as the dependent variable. The raTKA group had a regression coefficient of 9.09 (95% CI [1.10–17.1], p = 0.026), indicating a significant positive association with FJS compared to the cTKA group. This finding suggests that patients in the raTKA group tend to report higher functional scores. Regarding gender, male patients showed a significant positive association with FJS (coef. = 11.50 95% CI [3.59–19.4], p = 0.005), indicating that men tend to report higher FJS scores. On the other hand, no statistically significant association was observed between age and FJS (coef. = 0.15; 95% CI [-0.29–0.59]; p = 0.509), nor between BMI and FJS (coef. = 0.65; 95% CI [-0.38–1.68]; p = 0.214) (Table 3). Thus, patients in the raTKA group and male participants had superior functional results, reflecting a more favorable perception of their joint function and prosthesis integration. Table 3 Association Between the Use of Robotic-Assisted TKA and the Functional FJS Score Variable Coefficient 95% CI p value Age 0.15 −0.29 to 0.59 0.509 Male sex 11.50 3.59 to 19.40 0.005 BMI 0.65 −0.38 to 1.68 0.214 ATJr 9.09 1.10 to 17.10 0.026 BMI = body mass index; Coef = coefficient; ATJr = robotic-assisted total knee arthroplasty; CI = confidence interval. DISCUSSION Our study demonstrated that patients in the raTKA group and males had better FJS scores, reflecting a more favorable perception of their joint function. Other studies have also demonstrated these differences in functional scores, such as a literature review ( 5 ) and a meta-analysis involving 517 patients ( 1 ). However, other studies, including a retrospective observational study and literature reviews ( 6 , 7 ), failed to show significant differences in functional scores between patients undergoing conventional surgery (cTKA) and those undergoing robot-assisted surgery (rTKA). According to multiple linear regression, it was possible to observe that the cTKA group had a significant negative regression coefficient with the FJS, compared to the raTKA group. The data indicate that individuals in the cTKA group tend to report worse functional scores. Male participants, on the other hand, showed a significant positive association with FJS, suggesting that men tend to have higher scores. On the other hand, no statistically significant relationship was identified between BMI and FJS. Thus, it can be observed that both undergoing raTKA and being male are factors associated with better functional outcomes, reflecting a more positive perception of joint function and adaptation to the prosthesis, compared to cTKAc and females. Another study also reinforces these findings, such as a meta-analysis ( 8 ), which found that the TKA group had higher postoperative FJS than the TKA group. Although the raTKA group had a lower incidence of postoperative pain compared to the cTKA group, this difference was not statistically significant. Regarding return to physical activity, the results also showed no statistical differences between the groups. We believe that cohorts with a larger number of patients may demonstrate some statistically relevant differences in these aspects. Several studies show that robotic surgery is becoming an increasingly prevalent alternative due to its greater surgical precision, as it is possible to provide real-time data and greater standardization of resection, cutting, and bone alignment, thanks to its bone landmark recognition technology ( 3 , 8 ). The result would thus be a knee with greater stability, better rotational movement, and no restrictions on important ranges of motion ( 9 ). Despite this, there is still no consensus that the functional results and satisfaction of robotics would be better than conventional methods ( 3 ) In a cohort study conducted by Clement et al. ( 10 ), patients undergoing raTKA showed clinically significant improvement in knee pain in the first 12 months postoperatively, with a p-value of 0.029. In addition, these patients were significantly more likely to have their expectations for daytime pain relief met, compared to the group undergoing the conventional technique (p = 0.039). These findings suggest that robot-assisted surgery may provide better postoperative pain outcomes and higher patient satisfaction. However, functional outcome scores were not significantly different between techniques ( 3 ). In the present study, the TKA cohort had a considerably lower mean patient satisfaction score, indicating greater satisfaction among patients undergoing the robotic technique. This study has limitations. First, it is a retrospective cohort study. Since the data were obtained from pre-existing electronic medical records, potentially introducing systematic differences between the study groups, as well as bias arising from patients' recall during the questionnaires, could also affect the generalization of the results. Despite standardized surgical protocols and multivariable regression adjustment, this retrospective, non-randomized study remains susceptible to residual confounding. Allocation to the cTKA or raTKA groups was determined by routine clinical practice and may have been influenced by unmeasured patient and surgeon-related factors, including baseline functional status, limb alignment, disease severity, surgeon preference, and temporal adoption of robotic technology. Therefore, causal inferences should be interpreted with caution. Another limitation relates to the follow-up time, which does not allow this study to measure the long-term functional and survival outcomes of the prosthesis. Finally, the sample being composed of patients from a single center, using only one robot and prosthesis model, is also a limitation and restricts the generalization of the findings to other populations. CONCLUSIONS This study provides evidence that, after a postoperative period of at least one year, robotic assistance in total knee arthroplasty is associated with significantly higher scores on the Forgotten Joint Score, indicating a more favorable functional perception by patients compared to the conventional method. However, no significant differences were observed between the groups in other clinical outcomes evaluated, such as pain, satisfaction, and return to activities. Abbreviations OA: Osteoarthritis TKA: Total Knee Arthroplasty cTKA: Conventional Total Knee Arthroplasty raTKA: TKA with the assistance of a robotic arm FJS: Forgotten Joint Score Declarations COMPETING INTERESTS: The authors declare that they have no competing interests. FUNDING: No grant money was received for this research. Author Contribution Each author contributed individually and significantly to the development of the article. JPFG: wrote and reviewed the article, analyzed the results and developed the statistical analysis,participated in the intellectual conception of the study and coordinated the entire project; CPBS:collected data, wrote and revised the article; CAFS: collected data, wrote and revised the article; GFFP: collected data, wrote and revised the article; MPJJ: collected data, wrote and revised the article; PRB: analyzed the results and developed the statistical analysis; MVD: reviewed the article, participated in the intellectual conception of the study. References Ren Y, Cao S, Wu J, Weng X, Feng B (2019) Efficacy and reliability of active robotic-assisted total knee arthroplasty compared with conventional total knee arthroplasty: a systematic review and meta-analysis. Postgrad Med J 95(1121):125–133. 10.1136/postgradmedj-2018-136190 Epub 2019 Feb 26. PMID: 30808721; PMCID: PMC6585281 Kayani B, Konan S, Ayuob A, Onochie E, Al-Jabri T, Haddad FS (2019) Robotic technology in total knee arthroplasty: a systematic review. EFORT Open Rev 4(10):611–617. 10.1302/2058-5241.4.190022 PMID: 31754467; PMCID: PMC6836078 Yuan M, Ling T, Su Q, Wan X, Lai Y, Zhou Z (2024) Safety and Effectiveness of Robotic-Arm Assisted Total Knee Arthroplasty. Orthop Surg 16(4):882–893. 10.1111/os.14008 Epub 2024 Feb 26. PMID: 38404194; PMCID: PMC10984807 Ferreira MC, Silva G, Zidan FF, Franciozi CE, Luzo MVM, Abdalla RJ (2018) Forgotten Joint Score - Portuguese translation and cultural adaptation of the instrument of evaluation for hip and knee arthroplasties. Rev Bras Ortop 53(2):221–225 PMID: 29911090; PMCID: PMC6001155 Goncalves THC, Mendes CLS, Rodrigues SRM, de Oliveira GN, Vargas AS (2025) Feb Cirurgia robótica em ortopedia: impactos na artroplastia de quadril e joelho. Braz. J. Hea. Rev. [Internet]. 12 [cited 2026 Jan. 29];8(1):e77503. Available from: https://ojs.brazilianjournals.com.br/ojs/index.php/BJHR/article/view/77503 Marchand RC, Sodhi N, Khlopas A, Sultan AA, Harwin SF, Malkani AL et al (2017) Patient Satisfaction Outcomes after Robotic Arm-Assisted Total Knee Arthroplasty: A Short-Term Evaluation. J Knee Surg 13 de outubro de 30:849–853 Oliveira Filho OLD, Valle AL, Borba PHC, Fabricio MCF, Pereira RC, Ribeiro DF et al (2024) Comparação das complicações perioperatórias em artroplastia total de joelho: Abordagem robótica versus convencional – uma revisão da literatura. Res Soc Dev 14 de setembro de 13(9):e3813946748 Fu X, She Y, Jin G et al (2024) Comparison of robotic-assisted total knee arthroplasty: an updated systematic review and meta-analysis. J Robot Surg 18(1):292 Published 2024 Jul 25. 10.1007/s11701-024-02045-y Holthof SR, Rock M, van Arkel R, Brivio A, Barrett D, Amis AA (2025) Evaluation of a novel robotic testing method for stability and kinematics of total knee arthroplasty. Knee surgery, sports traumatology, arthroscopy: official journal of the ESSKA [Internet]. ;33(4):1387–96. Available from: https://pubmed.ncbi.nlm.nih.gov/39445624/ Clement ND, Galloway S, Baron J, Smith K, Weir DJ, Deehan DJ (2024) Patients undergoing robotic arm-assisted total knee arthroplasty have a greater improvement in knee-specific pain but not in function. Bone Joint J 106–B(5):450–459 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 23 Mar, 2026 Read the published version in Journal of Robotic Surgery → Version 1 posted Editorial decision: Revision requested 03 Mar, 2026 Reviews received at journal 03 Mar, 2026 Reviewers agreed at journal 03 Mar, 2026 Reviews received at journal 02 Mar, 2026 Reviewers agreed at journal 26 Feb, 2026 Reviewers invited by journal 18 Feb, 2026 Editor assigned by journal 11 Feb, 2026 Submission checks completed at journal 11 Feb, 2026 First submitted to journal 04 Feb, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8790936","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":594696539,"identity":"c4b43fab-09d3-4355-aa14-9fc44324d8df","order_by":0,"name":"JOAO PAULO 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1","display":"","copyAsset":false,"role":"figure","size":53638,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of patients recruited for the study.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8790936/v1/ab8183c28172b1dffb889e4b.png"},{"id":103362840,"identity":"6c168b28-9d5b-4d25-b8ca-6112d7ccfa32","added_by":"auto","created_at":"2026-02-24 21:34:45","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":19945,"visible":true,"origin":"","legend":"\u003cp\u003eForgotten Joint Score by type of surgery\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-8790936/v1/1d39662c39d7a6faa88df6df.png"},{"id":105755623,"identity":"29a40074-0ebb-427d-8f1a-b342d51016fa","added_by":"auto","created_at":"2026-03-30 16:28:38","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":630582,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8790936/v1/3ad6b74c-50e8-4151-9681-4ba63983955b.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eForgotten Joint Score\" one year after robot-assisted total knee arthroplasty\u003c/p\u003e","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eDespite significant advances in prosthesis design, surgical techniques, and postoperative rehabilitation protocols over the past two decades, between 10% and 20% of patients remain dissatisfied after total knee arthroplasty using the conventional technique (TKA) (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). Widely cited factors related to this dissatisfaction include inaccurate prosthesis positioning and suboptimal restoration of limb alignment (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTherefore, robotic technology has been incorporated into knee arthroplasty surgery to help surgeons achieve greater precision in bone cutting, restore mechanical alignment and proper implant positioning, which are important factors in increasing the longevity of the prosthesis and improving functional outcomes (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Recent and initial evidence indicate that robotic surgery has provided better clinical outcomes, a lower incidence of complications, and more accurate postoperative limb alignment (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). The objective of this study was to analyze the postoperative results of patients who underwent cTKA compared to those who underwent robot-assisted total knee arthroplasty (raTKA).\u003c/p\u003e"},{"header":"MATERIALS AND METHODS","content":"\u003cp\u003e This study was approved by the Ethics Committee of the Pontifical Catholic University of Paran\u0026aacute;, under opinion 6.903.444. All patients signed informed consent for the use of their data in this study.\u003c/p\u003e \u003cp\u003eThe study included patients aged 18 years or older, of both sexes, who underwent primary total knee arthroplasty performed by same knee surgery team. Exclusion criteria included patients who underwent revision arthroplasty, those under 18 years of age, individuals whose medical records were inaccessible, patients who were lost to follow-up during the study period, refused to participate in the study, and, according to the established criteria (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e), patients who answered less than 8 of the 12 questions on the assessment questionnaire were excluded.\u003c/p\u003e \u003cp\u003eThis was a retrospective cohort study. Between October 2022 and September 2023, all patients who underwent TKA, both by the traditional method and robot-assisted, were selected. The surgical procedures were performed by four orthopedic surgeons, each with more than 10 years of experience in arthroplasty.\u003c/p\u003e \u003cp\u003eThe data were extracted from electronic medical records and systematically compiled into a standardized database. Patients were classified into two groups according to the type of TKA performed: one group of patients, raTKA, who underwent robotic-assisted total knee arthroplasty (ROSA\u0026reg; Knee System, Zimmer, Warsaw, IN, USA), and another group, cTKA, consisting of those who underwent conventional total knee arthroplasty. All patients received the same prosthesis models (NEXGEN\u0026reg;, Zimmer, Warsaw, IN, USA). After classification of the patients, those eligible for participation were contacted by evaluators blinded to the type of surgery performed to agree to the informed consent form, and if so, an adapted questionnaire was administered to assess clinical and functional outcomes. In addition functional outcomes were assessed using the Forgotten Joint Score (FJS), a validated instrument for hip and knee arthroplasty, culturally adapted to Portuguese (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e), which evaluates joint awareness in daily activities and the patient\u0026rsquo;s perceived knee function and prosthesis integration.\u003c/p\u003e \u003cp\u003eThe outcomes analyzed included the results of the FJS-12, pain complaints, return to physical activities, and satisfaction with the surgery. All assessments were performed at least one year after the surgical procedure.\u003c/p\u003e \u003cp\u003eThe Shapiro-Wilk test was used to verify the normality of numerical data. Qualitative data were represented by frequency and analyzed using the t-test or Mann-Whitney test, according to the normality result. Categorical data were represented by mean (SD) or median (IQR) and analyzed using Fisher's exact test. Multivariate linear regression analysis was also performed to evaluate the factors associated with the outcome. All statistical analyses were performed using STATA v.16 software (Stata Corporation LLC, College Station, USA), with a significance level of 5% for all tests applied.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003eAll 222 patients who underwent surgery during the study period were selected, and 186 agreed to participate in the study and were initially included. Of these, 26 refused to answer the questionnaires, 9 were lost to follow-up, and there was 1 death during follow-up. Of the 186 patients recruited, 92 were part of the group that underwent cTAH, and 94 were part of the group that underwent rTAH. Of the 26 patients who refused to participate in the study, 17 were part of the conventional group, and 9 were part of the robot-assisted group. The patient who died belonged to the cTAH group (Fig.\u0026nbsp;1).\u003c/p\u003e\n\u003cp\u003eAccording to the previously established questionnaire validity criteria, five patients were subsequently excluded from the analysis: four from the raTKA group, three due to incomplete responses and one due to postoperative infection, and one from the cTKA group due to an insufficient number of responses.\u003c/p\u003e\n\u003cp\u003eIn the final analysis, therefore, 181 patients were included, totaling 91 patients in the cTKA group and 90 who underwent raTKA. The mean age of the raTKA group was 68.1\u0026thinsp;\u0026plusmn;\u0026thinsp;8.9, while that of the cTKA group was 68.6\u0026thinsp;\u0026plusmn;\u0026thinsp;9.0 (Table\u0026nbsp;1).\u003c/p\u003e\n\u003cp\u003eNo statistically significant difference was observed between the groups in terms of gender distribution. However, the body mass index (BMI) was significantly higher in the raTKA group compared to the cTKA group, with a mean of 29.4 (27.2\u0026ndash;32.1) versus 28.4 (25.0\u0026ndash;30.8), respectively (p\u0026thinsp;=\u0026thinsp;0.039) (Table 1).\u003c/p\u003e\n\u003cdiv\u003e\u0026nbsp;\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv\u003eTable 1\u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eDemographic and Clinical Characteristics of the Patients\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"4\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCharacteristic\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eATJr (n\u0026thinsp;=\u0026thinsp;90)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eATJc (n\u0026thinsp;=\u0026thinsp;91)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAge, mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e68.1\u0026thinsp;\u0026plusmn;\u0026thinsp;8.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e68.6\u0026thinsp;\u0026plusmn;\u0026thinsp;9.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.637\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMale sex, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e47 (52.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e41 (45.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.416\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eBMI, median (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29.4 (27.2\u0026ndash;32.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e28.0 (25.0\u0026ndash;30.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.039\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eATJr\u0026thinsp;=\u0026thinsp;robotic-assisted total knee arthroplasty; ATJc\u0026thinsp;=\u0026thinsp;conventional total knee arthroplasty; n\u0026thinsp;=\u0026thinsp;number of patients; BMI\u0026thinsp;=\u0026thinsp;body mass index; IQR\u0026thinsp;=\u0026thinsp;interquartile range.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAs shown in Fig. 2, patient satisfaction with surgery (83.9% vs. 88.5%; p\u0026thinsp;=\u0026thinsp;0.349) did not differ significantly. The FJS showed significantly higher median scores in the raTKA group compared to the cTKA group (72.5 [54.1\u0026ndash;100] vs. 61.8 [39.6\u0026ndash;91.7]; p\u0026thinsp;=\u0026thinsp;0.004) (Table 2 and Fig. 2).\u003c/p\u003e\n\u003cdiv\u003e\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv\u003eTable 2\u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003ePatient-Reported Outcomes\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"4\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCharacteristic\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eATJr (n\u0026thinsp;=\u0026thinsp;90)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eATJc (n\u0026thinsp;=\u0026thinsp;91)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSatisfaction, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e92 (88.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e78 (83.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.349\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eReturn to physical activity, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e40 (43.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e48 (46.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.657\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePain, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e29 (27.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e34 (37.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.326\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFJS, median (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e72.5 (54.1\u0026ndash;100)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e61.8 (39.6\u0026ndash;91.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.004\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eATJr\u0026thinsp;=\u0026thinsp;robotic-assisted total knee arthroplasty; ATJc\u0026thinsp;=\u0026thinsp;conventional total knee arthroplasty; n\u0026thinsp;=\u0026thinsp;number of patients; FJS\u0026thinsp;=\u0026thinsp;Forgotten Joint Score; IQR\u0026thinsp;=\u0026thinsp;interquartile range.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe occurrence of pain was also evaluated between the groups, with 37.4% of patients in the control group reporting this complaint, compared to 27.8% in the robotic group. However, this difference did not reach statistical significance (p\u0026thinsp;=\u0026thinsp;0.326) (Table\u0026nbsp;2).\u003c/p\u003e\n\u003cp\u003eThe analysis of return to physical activity revealed that, among the patients evaluated, 43.0% in the raTKA group and 46.1% in the cTKA group reported never or rarely remembering the artificial joint while practicing their favorite sport. The difference between the groups, however, was not statistically significant, with a p-value of 0.657, indicating that the return to physical activity and perception of the prosthesis did not vary significantly between the two surgical methods (Table\u0026nbsp;2).\u003c/p\u003e\n\u003cp\u003eA multiple linear regression analysis was performed with FJS as the dependent variable. The raTKA group had a regression coefficient of 9.09 (95% CI [1.10\u0026ndash;17.1], p\u0026thinsp;=\u0026thinsp;0.026), indicating a significant positive association with FJS compared to the cTKA group. This finding suggests that patients in the raTKA group tend to report higher functional scores. Regarding gender, male patients showed a significant positive association with FJS (coef. = 11.50 95% CI [3.59\u0026ndash;19.4], p\u0026thinsp;=\u0026thinsp;0.005), indicating that men tend to report higher FJS scores. On the other hand, no statistically significant association was observed between age and FJS (coef. = 0.15; 95% CI [-0.29\u0026ndash;0.59]; p\u0026thinsp;=\u0026thinsp;0.509), nor between BMI and FJS (coef. = 0.65; 95% CI [-0.38\u0026ndash;1.68]; p\u0026thinsp;=\u0026thinsp;0.214) (Table 3). Thus, patients in the raTKA group and male participants had superior functional results, reflecting a more favorable perception of their joint function and prosthesis integration.\u003c/p\u003e\n\u003cdiv\u003e\u0026nbsp;\u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv\u003eTable 3\u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eAssociation Between the Use of Robotic-Assisted TKA and the Functional FJS Score\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"4\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eVariable\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCoefficient\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e95% CI\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026minus;0.29 to 0.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.509\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMale sex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e11.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.59 to 19.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.005\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eBMI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026minus;0.38 to 1.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.214\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eATJr\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e9.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.10 to 17.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.026\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eBMI\u0026thinsp;=\u0026thinsp;body mass index; Coef\u0026thinsp;=\u0026thinsp;coefficient; ATJr\u0026thinsp;=\u0026thinsp;robotic-assisted total knee arthroplasty; CI\u0026thinsp;=\u0026thinsp;confidence interval.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eOur study demonstrated that patients in the raTKA group and males had better FJS scores, reflecting a more favorable perception of their joint function. Other studies have also demonstrated these differences in functional scores, such as a literature review (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e) and a meta-analysis involving 517 patients (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). However, other studies, including a retrospective observational study and literature reviews (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e), failed to show significant differences in functional scores between patients undergoing conventional surgery (cTKA) and those undergoing robot-assisted surgery (rTKA).\u003c/p\u003e \u003cp\u003eAccording to multiple linear regression, it was possible to observe that the cTKA group had a significant negative regression coefficient with the FJS, compared to the raTKA group. The data indicate that individuals in the cTKA group tend to report worse functional scores. Male participants, on the other hand, showed a significant positive association with FJS, suggesting that men tend to have higher scores. On the other hand, no statistically significant relationship was identified between BMI and FJS. Thus, it can be observed that both undergoing raTKA and being male are factors associated with better functional outcomes, reflecting a more positive perception of joint function and adaptation to the prosthesis, compared to cTKAc and females. Another study also reinforces these findings, such as a meta-analysis (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e), which found that the TKA group had higher postoperative FJS than the TKA group.\u003c/p\u003e \u003cp\u003eAlthough the raTKA group had a lower incidence of postoperative pain compared to the cTKA group, this difference was not statistically significant. Regarding return to physical activity, the results also showed no statistical differences between the groups. We believe that cohorts with a larger number of patients may demonstrate some statistically relevant differences in these aspects.\u003c/p\u003e \u003cp\u003eSeveral studies show that robotic surgery is becoming an increasingly prevalent alternative due to its greater surgical precision, as it is possible to provide real-time data and greater standardization of resection, cutting, and bone alignment, thanks to its bone landmark recognition technology (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). The result would thus be a knee with greater stability, better rotational movement, and no restrictions on important ranges of motion (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Despite this, there is still no consensus that the functional results and satisfaction of robotics would be better than conventional methods (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eIn a cohort study conducted by Clement et al. (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e), patients undergoing raTKA showed clinically significant improvement in knee pain in the first 12 months postoperatively, with a p-value of 0.029. In addition, these patients were significantly more likely to have their expectations for daytime pain relief met, compared to the group undergoing the conventional technique (p\u0026thinsp;=\u0026thinsp;0.039). These findings suggest that robot-assisted surgery may provide better postoperative pain outcomes and higher patient satisfaction. However, functional outcome scores were not significantly different between techniques (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). In the present study, the TKA cohort had a considerably lower mean patient satisfaction score, indicating greater satisfaction among patients undergoing the robotic technique.\u003c/p\u003e \u003cp\u003eThis study has limitations. First, it is a retrospective cohort study. Since the data were obtained from pre-existing electronic medical records, potentially introducing systematic differences between the study groups, as well as bias arising from patients' recall during the questionnaires, could also affect the generalization of the results. Despite standardized surgical protocols and multivariable regression adjustment, this retrospective, non-randomized study remains susceptible to residual confounding. Allocation to the cTKA or raTKA groups was determined by routine clinical practice and may have been influenced by unmeasured patient and surgeon-related factors, including baseline functional status, limb alignment, disease severity, surgeon preference, and temporal adoption of robotic technology. Therefore, causal inferences should be interpreted with caution. Another limitation relates to the follow-up time, which does not allow this study to measure the long-term functional and survival outcomes of the prosthesis. Finally, the sample being composed of patients from a single center, using only one robot and prosthesis model, is also a limitation and restricts the generalization of the findings to other populations.\u003c/p\u003e"},{"header":"CONCLUSIONS","content":"\u003cp\u003eThis study provides evidence that, after a postoperative period of at least one year, robotic assistance in total knee arthroplasty is associated with significantly higher scores on the Forgotten Joint Score, indicating a more favorable functional perception by patients compared to the conventional method. However, no significant differences were observed between the groups in other clinical outcomes evaluated, such as pain, satisfaction, and return to activities.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eOA:\u0026nbsp;Osteoarthritis\u003c/p\u003e\n\u003cp\u003eTKA: Total Knee Arthroplasty\u003c/p\u003e\n\u003cp\u003ecTKA: Conventional Total Knee Arthroplasty raTKA:\u0026nbsp;TKA with the assistance of a robotic arm FJS: Forgotten Joint Score\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eCOMPETING INTERESTS:\u003c/h2\u003e \u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFUNDING:\u003c/h2\u003e \u003cp\u003eNo grant money was received for this research.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eEach author contributed individually and significantly to the development of the article. JPFG: wrote and reviewed the article, analyzed the results and developed the statistical analysis,participated in the intellectual conception of the study and coordinated the entire project; CPBS:collected data, wrote and revised the article; CAFS: collected data, wrote and revised the article; GFFP: collected data, wrote and revised the article; MPJJ: collected data, wrote and revised the article; PRB: analyzed the results and developed the statistical analysis; MVD: reviewed the article, participated in the intellectual conception of the study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eRen Y, Cao S, Wu J, Weng X, Feng B (2019) Efficacy and reliability of active robotic-assisted total knee arthroplasty compared with conventional total knee arthroplasty: a systematic review and meta-analysis. Postgrad Med J 95(1121):125\u0026ndash;133. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1136/postgradmedj-2018-136190\u003c/span\u003e\u003cspan address=\"10.1136/postgradmedj-2018-136190\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub 2019 Feb 26. PMID: 30808721; PMCID: PMC6585281\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKayani B, Konan S, Ayuob A, Onochie E, Al-Jabri T, Haddad FS (2019) Robotic technology in total knee arthroplasty: a systematic review. EFORT Open Rev 4(10):611\u0026ndash;617. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1302/2058-5241.4.190022\u003c/span\u003e\u003cspan address=\"10.1302/2058-5241.4.190022\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003ePMID: 31754467; PMCID: PMC6836078\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYuan M, Ling T, Su Q, Wan X, Lai Y, Zhou Z (2024) Safety and Effectiveness of Robotic-Arm Assisted Total Knee Arthroplasty. Orthop Surg 16(4):882\u0026ndash;893. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/os.14008\u003c/span\u003e\u003cspan address=\"10.1111/os.14008\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub 2024 Feb 26. PMID: 38404194; PMCID: PMC10984807\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFerreira MC, Silva G, Zidan FF, Franciozi CE, Luzo MVM, Abdalla RJ (2018) Forgotten Joint Score - Portuguese translation and cultural adaptation of the instrument of evaluation for hip and knee arthroplasties. Rev Bras Ortop 53(2):221\u0026ndash;225 PMID: 29911090; PMCID: PMC6001155\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGoncalves THC, Mendes CLS, Rodrigues SRM, de Oliveira GN, Vargas AS (2025) Feb Cirurgia rob\u0026oacute;tica em ortopedia: impactos na artroplastia de quadril e joelho. Braz. J. Hea. Rev. [Internet]. 12 [cited 2026 Jan. 29];8(1):e77503. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://ojs.brazilianjournals.com.br/ojs/index.php/BJHR/article/view/77503\u003c/span\u003e\u003cspan address=\"https://ojs.brazilianjournals.com.br/ojs/index.php/BJHR/article/view/77503\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMarchand RC, Sodhi N, Khlopas A, Sultan AA, Harwin SF, Malkani AL et al (2017) Patient Satisfaction Outcomes after Robotic Arm-Assisted Total Knee Arthroplasty: A Short-Term Evaluation. J Knee Surg 13 de outubro de 30:849\u0026ndash;853\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOliveira Filho OLD, Valle AL, Borba PHC, Fabricio MCF, Pereira RC, Ribeiro DF et al (2024) Compara\u0026ccedil;\u0026atilde;o das complica\u0026ccedil;\u0026otilde;es perioperat\u0026oacute;rias em artroplastia total de joelho: Abordagem rob\u0026oacute;tica versus convencional \u0026ndash; uma revis\u0026atilde;o da literatura. Res Soc Dev 14 de setembro de 13(9):e3813946748\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFu X, She Y, Jin G et al (2024) Comparison of robotic-assisted total knee arthroplasty: an updated systematic review and meta-analysis. J Robot Surg 18(1):292 Published 2024 Jul 25. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s11701-024-02045-y\u003c/span\u003e\u003cspan address=\"10.1007/s11701-024-02045-y\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHolthof SR, Rock M, van Arkel R, Brivio A, Barrett D, Amis AA (2025) Evaluation of a novel robotic testing method for stability and kinematics of total knee arthroplasty. Knee surgery, sports traumatology, arthroscopy: official journal of the ESSKA [Internet]. ;33(4):1387\u0026ndash;96. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://pubmed.ncbi.nlm.nih.gov/39445624/\u003c/span\u003e\u003cspan address=\"https://pubmed.ncbi.nlm.nih.gov/39445624/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eClement ND, Galloway S, Baron J, Smith K, Weir DJ, Deehan DJ (2024) Patients undergoing robotic arm-assisted total knee arthroplasty have a greater improvement in knee-specific pain but not in function. Bone Joint J 106\u0026ndash;B(5):450\u0026ndash;459\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-robotic-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jors","sideBox":"Learn more about [Journal of Robotic Surgery](http://link.springer.com/journal/11701)","snPcode":"11701","submissionUrl":"https://submission.nature.com/new-submission/11701/3","title":"Journal of Robotic Surgery","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Osteoarthritis, Knee, Conventional arthroplasty, Arthroplasty with robotic arm","lastPublishedDoi":"10.21203/rs.3.rs-8790936/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8790936/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective: \u003c/strong\u003eThe objective of this study was to analyze the postoperative results of patients who underwent cTKA compared to those who underwent robot-assisted total knee arthroplasty (raTKA).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eA retrospective analysis was conducted on patients who underwent primary TKA. Patients were classified into two groups based on prosthesis type. Functional outcomes were assessed using the Forgotten Joint Score (FJS). Statistical analysis included multiple linear regression to identify predictors of joint awareness.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eA total of 181 patients were analyzed (raTKA group: \u003cem\u003en \u003c/em\u003e= 90; cTKA group: \u003cem\u003en \u003c/em\u003e= 91). FJS scores were significantly higher in the raTKA group (72,5 [54.1–100]) than in the cTKA group (61.8 [39.6–91.7]; \u003cem\u003ep \u003c/em\u003e= 0.004). Regression analysis identified the male sex (coef. = 11.50, \u003cem\u003ep \u003c/em\u003e= 0.005) as a positive predictor of FJS, while cTKA group was associated with lower scores (coef. = -9.09, \u003cem\u003ep \u003c/em\u003e= 0.026). Body mass index showed no significant association with FJS (coef. = 0.65, \u003cem\u003ep \u003c/em\u003e= 0.214).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eSurgery type and sex influence joint awareness post-TKA. Male patients and raTKA group demonstrating superior functional perception. These findings underscore the importance of prosthesis selection in optimizing postoperative outcomes.\u003c/p\u003e","manuscriptTitle":"Forgotten Joint Score\" one year after robot-assisted total knee arthroplasty","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-24 21:34:40","doi":"10.21203/rs.3.rs-8790936/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-04T00:12:33+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-03T20:00:48+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"5773735517130762528310565009725233008","date":"2026-03-03T18:48:46+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-02T09:30:47+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"259482808797664083530463301482168628107","date":"2026-02-26T19:53:03+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-02-19T00:39:56+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-11T19:00:05+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-11T06:58:14+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Robotic Surgery","date":"2026-02-05T00:41:51+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-robotic-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jors","sideBox":"Learn more about [Journal of Robotic Surgery](http://link.springer.com/journal/11701)","snPcode":"11701","submissionUrl":"https://submission.nature.com/new-submission/11701/3","title":"Journal of Robotic Surgery","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"bdcc68bb-7cec-4dbf-b0d5-ad91c4dfe41d","owner":[],"postedDate":"February 24th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-03-30T16:23:27+00:00","versionOfRecord":{"articleIdentity":"rs-8790936","link":"https://doi.org/10.1007/s11701-026-03340-6","journal":{"identity":"journal-of-robotic-surgery","isVorOnly":false,"title":"Journal of Robotic Surgery"},"publishedOn":"2026-03-23 16:08:55","publishedOnDateReadable":"March 23rd, 2026"},"versionCreatedAt":"2026-02-24 21:34:40","video":"","vorDoi":"10.1007/s11701-026-03340-6","vorDoiUrl":"https://doi.org/10.1007/s11701-026-03340-6","workflowStages":[]},"version":"v1","identity":"rs-8790936","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8790936","identity":"rs-8790936","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}