Patient-Reported Functional and Satisfaction Outcomes after Robotic-Arm-Assisted Total Knee Arthroplasty: Early Results of a Prospective Multicenter Investigation

Robotic assisted Total Knee Arthroplasty (TKA) is not associated with increased patient satisfaction: a systematic review and meta-analysis

PURPOSE

Total knee arthroplasty (TKA) is a common orthopedic surgery, yet postoperative dissatisfaction persists in around 20% of cases. Robotic total knee arthroplasty (rTKA) promises enhanced precision, but its impact on patient satisfaction compared to conventional TKA remains controversial (cTKA). This systematic review aims to evaluate patient satisfaction post-rTKA and compare outcomes with cTKA.

METHODS

Papers from the following databases were identified and reviewed: PubMed, Scopus, Web of Science, and the Cochrane Online Library, using keywords like "Knee replacement," "Total knee arthroplasty," "Robotic," and "Patient satisfaction." Extracted data included patient satisfaction measures, Knee Society Score, Oxford Knee Score, Forgotten Joint Score, SF-36, HSS, and KOOS. Statistical analysis, including odds ratio and 95% CI was performed using R software. Heterogeneity was assessed using Cochrane's Q test.

RESULTS

The systematic review included 17 articles, involving 1148 patients (571 in the rTKA group and 577 in the cTKA group) assessing patient satisfaction following rTKA. An analysis of proportions reveals rTKA satisfaction rate was 95%, while for cTKA, it was 91%. A meta-analysis comparing rTKA and cTKA found no statistically significant difference in patient satisfaction. Additionally, various patient-reported outcome measures (PROMs) were examined, showing mixed results across different studies and follow-up periods.

CONCLUSIONS

The results of this study found no difference in patient satisfaction outcomes in the short to mid-term for rTKA compared to conventional methods. This study does not assert superiority for the robotic approach, highlighting the need for careful consideration of various factors influencing outcomes in knee arthroplasty.

Robotic-assisted total knee arthroplasty is associated with the use of thinner polyethylene liners compared to navigation-guided and manual techniques

PURPOSE

The purpose of this study was to examine the effects of intraoperative technology use on the rate of using polyethylene liners 15 mm or greater during primary total knee arthroplasty (TKA).

METHODS

There were 103,295 implants from 16,386 primary unilateral TKAs performed on 14,253 patients at a single institution between 1 January 2018, and 30 June 2022, included in the current study. Robotic assistance and navigation guidance were used in 1274 (8%) and 8345 (51%) procedures, respectively. The remaining 6767 TKAs (41%) were performed manually. Polyethylene liners were manually identified and further subcategorised by implant thickness. Patients who underwent robotic-assisted TKA were younger (p < 0.001) and more likely to be male (p < 0.001) compared to patients who underwent navigation-guided or manual TKAs.

RESULTS

Average polyethylene liner thickness was similar between groups (10.5 ± 1.5 mm for robotic-assisted TKAs, 10.9 ± 1.8 mm for navigation-guided TKAs and 10.8 ± 1.8 mm for manual TKAs). The proportions of polyethylene liners 15 mm or greater used were 4.9%, 3.8% and 1.9% for navigation-guided, manual and robotic-assisted procedures, respectively (p < 0.001). Multivariate regression analyses demonstrated that navigation-guided (odds ratio [OR]: 2.6, 95% confidence Interval [CI]: [1.75-4.07], p < 0.001) and manual (OR: 2.0, 95% CI: [1.34-3.20], p = 0.001) procedures were associated with an increased use of polyethylene liners 15 mm or greater.

CONCLUSION

Robotic-assisted TKA was associated with a lower proportion of polyethylene liners 15 mm or greater used compared to navigation-guided and manual TKA. These findings suggest that robotic assistance can reduce human error via a more precise cutting system, limit over-resection of the tibia and flexion-extension gap mismatch and ultimately allow for more appropriately sized implants.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Operating room efficiency for a high-volume surgeon in simultaneous bilateral robotic-assisted total knee arthroplasty: a prospective cohort study

Robotic-assisted total knee arthroplasty (RATKA) has been shown to achieve more accurate component positioning and target alignment than conventional jig-based instrumentation; however, concerns remain regarding its adoption since it is associated with steep learning curves, higher operational costs, and increased surgical time. This study aims to compare the operating times of three cohorts of patients undergoing simultaneous bilateral TKA, i.e., first 50 RATKA, last 50 RATKA (at the end of 1 year), and 50 conventional TKA. This prospective cohort study was conducted at a single high-volume tertiary care center by a single experienced surgeon on 150 patients (300 knees), who were allotted into three equal cohorts of 50, between February 2020 and December 2021. Simultaneous bilateral TKAs were done in all three groups and operative times recorded. We describe the technique for optimizing the surgical time of SB-RATKA for efficient operative room logistics. The operating times of the two robotic-assisted TKA cohorts were compared with the operating times of the conventional SB-TKA cohort. The mean age of the study population was 59(±6.2) years with the majority of females (82%). The mean coronal deformity was comparable between the cohorts. The mean operating time in the conventional CTKA, initial 50 RATKA, and final 50 RATKA cohorts were 115.56 (±10.7), 127.8 (±26), and 91.66 (±13.5) min, respectively, all of which showed a statistically significant difference (p < 0.001). The mean operating times of the final 50 RATKA at the end of 1 year improved by about 36 min with all the SB-RATKA cases being completed in under 120 min. The efficiency of SB-RATKA improved significantly with time and experience, resulting in shorter operational times within a year, revealing the potential of robotic-assisted surgery to surpass conventional approaches in TKA in terms of operating room efficiency.

Pitfalls with the MAKO Robotic-Arm-Assisted Total Knee Arthroplasty

Robotic-arm-assisted total knee arthroplasty (RATKA) with the MAKO system minimizes deviations in implant alignment and yields superior precision in implant position compared to a manual total knee arthroplasty. In this comprehensive commentary, we present and categorize the limitations and pitfalls of the procedure and we also provide recommendations for avoiding each limitation. The main surgeon-related limitations include prolonged operation duration, loose insertion of the checkpoints and pins, wrong registration and mapping, and damage to soft tissues during bone cutting. The system-related issues include the interruptions of the saw-cutting due to vibrations, specifications for the operating room floor and power supply, the high cost of the system, as well as the cost of each operation due to the extra implants, inability to use the system with various prostheses, wireless connection interruptions between the system's components, and hardware issues with the six joints of the robotic device. In order to circumvent the potential challenges in this surgical procedure, it is essential to possess sufficient experience and undergo comprehensive training. Maintaining continuous awareness of the additional implants throughout the entire operation and prioritizing the preservation of soft tissues are of paramount significance. A profound comprehension of the system and its inherent constraints can also prove to be pivotal in certain situations.

Robotic-assisted TKA is Not Associated With Decreased Odds of Early Revision: An Analysis of the American Joint Replacement Registry

BACKGROUND

Robotic-assisted TKA continues to see wider clinical use, despite limited knowledge of its impact on patient satisfaction and implant survival. Most studies to date have presented small cohorts and came from single-surgeon or single-center experiences. Therefore, a population-level comparison of revision rates between robotic-assisted and conventional TKA in the registry setting may help arthroplasty surgeons better define whether robotic assistance provides a meaningful advantage compared with the conventional technique.

QUESTIONS/PURPOSES

(1) After controlling for confounding variables, such as surgeon, location of surgery, and patient comorbidity profile, were robotic-assisted TKAs less likely than conventional TKAs to result in revision for any reason at 2 years? (2) After again controlling for confounding variables, were robotic-assisted TKAs less likely to result in any specific reasons for revision than the conventional technique at 2 years?

METHODS

The American Joint Replacement Registry was used to identify patients 65 years or older who underwent TKA between January 2017 and March 2020 with a minimum of 2 years of follow-up. Patients were limited to age 65 yeas or older to link TKAs to Medicare claims data. Two retrospective cohorts were created: robotic-assisted TKA and conventional TKA. Patient demographic variables included in the analysis were age, gender, BMI, and race. Additional characteristics included the Charlson comorbidity index, anesthesia type, year of the index procedure, and length of stay. A total of 10% (14,216 of 142,550) of TKAs performed during this study period used robotics. Patients with robotic-assisted TKA and those with conventional TKA were similar regarding age (73 ± 6 years versus 73 ± 6 years; p = 0.31) and gender (62% [8736 of 14,126] versus 62% [79,399 of 128,334] women; p = 0.34). A multivariable, mixed-effects logistic regression model was created to analyze the odds of all-cause revision as a factor of robot use, and a logistic regression model was created to investigate specific revision diagnoses.

RESULTS

After controlling for potentially confounding variables, such as surgeon, location of surgery, and Charlson comorbidity index, we found no difference between the robotic-assisted and conventional TKAs in terms of the odds of revision at 2 years (OR of robotic-assisted versus conventional TKA 1.0 [95% CI 0.8 to 1.3]; p = 0.92). The reasons for revision of robotic-assisted TKA did not differ from those of conventional TKA, except for an increased odds of instability (OR 1.6 [95% CI 1.0 to 2.4]; p = 0.04) and pain (OR 2.1 [95% CI 1.4 to 3.0]; p < 0.001) in the robotic-assisted cohort.

CONCLUSION

In light of these findings, surgeons should not assume that robotic assistance in TKA will lead to improved early implant survival. Our findings do not support an improvement over conventional TKA with robotic assistance with regards to common causes of early revisions such malalignment, malposition, stiffness, pain, and instability, and in some cases, suggest there is a benefit to conventional TKA. Differences in the mid-term and long-term revision risk with conventional versus robotic-assisted TKA remain unknown. Appropriate informed consent around the use of robotic assistance should not imply decreased early revision risk.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Robotic Arm-Assisted Total Knee Arthroplasty: Anatomical Alignment and Mid-Term Outcomes from the First Cohort Originating in Greece

Robotic arm-assisted total knee arthroplasty (RATKA) represents a haptic assistive robotic arm used for bone preparation. The purpose of this study was to present implant survivorship, complications and evaluate patients' satisfaction, clinical and functional outcome of RATKA with a minimum of 1-year follow-up. The Oxford Knee Score was recorded preoperatively and at last follow-up. Patients' satisfaction rates, as well as complications and re-operations were studied. Anatomical alignment including varus, valgus deformities and flexion, extension, pre-and postoperatively were evaluated. A total of 156 patients with mean age = 71.9 years were included in the study. The mean follow-up was 35.7 months, while one revision was performed due to infection. Statistically significant improvement of the Oxford Knee Score, as well as of the knee alignment deformities were recorded, while 99.4% of patients reported to be "very satisfied" or "satisfied" with the procedure. RATKA seems to be a safe, as well as reproductible procedure at short-and mid-term follow-up, while the accurate implant positioning may lead to favorable long-term outcomes.

Systematic review and meta-analysis of economic and healthcare resource utilization outcomes for robotic versus manual total knee arthroplasty

The introduction of robotics in orthopedic surgery has led to improved precision and standardization in total knee arthroplasty (TKA). Clinical benefits of robotic versus manual TKA have been well established; however, evidence for economic and healthcare resource utilization outcomes (HRU) is lacking. The primary objective of this study was to compare economic and HRU outcomes for robotic and manual TKA. The secondary objective was to explore comparative robotic and manual TKA pain and opioid consumption outcomes. Multi-database literature searches were performed to identify studies comparing robotic and manual TKA from 2016 to 2022 and meta-analyses were conducted. This review included 50 studies with meta-analyses conducted on 35. Compared with manual TKA, robotic TKA was associated with a: 14% reduction in hospital length of stay (P = 0.022); 74% greater likelihood to be discharged to home (P < 0.001); and 17% lower likelihood to experience a 90-day readmission (P = 0.043). Robotic TKA was associated with longer mean operating times (incision to closure definition: 9.27 min longer, P = 0.030; general operating time definition: 18.05 min longer, P = 0.006). No differences were observed for total procedure cost and 90-day emergency room visits. Most studies reported similar outcomes for robotic and manual TKA regarding pain and opioid use. Coupled with the clinical benefits of robotic TKA, the economic impact of using robotics may contribute to hospitals' quality improvement and financial sustainability. Further research and more randomized controlled trials are needed to effectively quantify the benefits of robotic relative to manual TKA.

Comparison of Postoperative Pain and Function in Robotic Total Knee Arthroplasty and Conventional Total Knee Arthroplasty Amongst Patients at King Fahad Medical City in Riyadh, Saudi Arabia

Background Total knee arthroplasty (TKA) is the definitive surgical treatment for end-stage osteoarthritis and has been proven to relieve pain and improve function. With the rise in demand and the number of TKA procedures every year, more studies have been conducted on robotic TKA. Objective The objective of this study is to compare the postoperative pain between robotic and conventional TKA and the postoperative functional level between robotic and conventional TKA. Method This is a quantitative, observational, prospective study conducted from February 2022 to August 2022 amongst patients in the orthopaedic department of King Fahad Medical City, Riyadh, Saudi Arabia, who have undergone primary TKA for end-stage osteoarthritis using robotic TKA and conventional TKA. After applying the exclusion and inclusion criteria, a total of 26 patients (12 robotic and 14 conventional) were included in the study. The patients were assessed at three time points: two weeks, six weeks, and three months post-op. They were assessed using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) score and the visual analogue scores (VAS) used to assess pain. Result A total of 26 patients were included in this research. The patients were divided into two groups: 12 robotic TKA patients and 14 conventional TKA patients. In this study, while comparing patients who underwent robotic TKA with those who underwent conventional TKA, no statistical significance was found regarding pain and function at all stages postoperatively. Conclusion There was no short-term difference between robotic and conventional TKA regarding pain and function. There is a need for further extensive research on robotic TKA in terms of cost-effectiveness, complications, implant survivorship, and long-term outcomes.

Decreased patient comorbidities and post-operative complications in technology-assisted compared to conventional total knee arthroplasty

PURPOSE

The use of computer-assisted and robotic surgery was developed to improve component position and outcomes of total knee arthroplasty (TKA). The goal of this study is to identify differences in patient demographics, comorbidities, and complications between technology-assisted and conventional TKA.

METHODS

A Nationwide Inpatient Sample database was used to identify patients who underwent technology-assisted and conventional TKA from 2016 to 2018. Analysed variables include demographics, length of stay (LOS), payer-status, geographic region, comorbidities, complications, and mortality. Univariate and multivariate analyses were performed to identify differences between both groups.

RESULTS

The analysis includes 2,208,434 TKA patients, of which 2,054,879 (93.05%) were conventional and 153,555 (6.95%) were technology assisted. Patients undergoing technology-assisted TKA were more likely to be older than 65 years, had higher median income quartile, and had surgery in urban teaching hospitals. Patients were less likely to undergo technology-assisted TKA if they were female gender, had Medicare payer status, were black race, were obese, were living in rural location, or had higher Charlson comorbidity score and baseline comorbidities. Technology-assisted TKA patients had shorter LOS, and fewer pulmonary and infection complications.

CONCLUSION

Patients undergoing technology-assisted TKA are being carefully selected with less baseline comorbidities, improved health, and living in urban areas. Subsequently, those carefully selected patients are discharged home, have a shorted hospital LOS, and have fewer complications compared to conventional TKA. Rural patients, black race and female gender are less likely to undergo technology-assisted TKA, further emphasizing the healthcare disparity for that segment of the population.

LEVEL OF EVIDENCE

Therapeutic level III.

Functional alignment with robotic‑arm assisted total knee arthroplasty demonstrated better patient-reported outcomes than mechanical alignment with manual total knee arthroplasty

PURPOSE

Given the improved accuracy of robot-assisted surgery, robotic-arm assisted functionally aligned total knee arthroplasty (RFA-TKA) aims to preserve the native pre-arthritic knee biomechanics, to achieve balanced flexion-extension gaps. The purpose of this study was to compare the accuracy of the implant position and short-term clinical outcomes of patients who underwent RFA-TKA vs. mechanically aligned total knee arthroplasty with manual technique (MA-TKA).

METHODS

A prospectively collected database was reviewed retrospectively for patients who underwent primary TKA. Sixty patients who underwent RFA-TKA between February 2020 and July 2020 were included in the RFA-TKA group. Sixty patients who underwent MA-TKA were included via 1:1 matching for age, sex, and body mass index based on the RFA-TKA group. For radiological evaluation, knee X-rays were used to assess the functional knee phenotype and implant position accuracy by measuring the coronal and sagittal alignment, and these measurements were compared between the two groups. Patient demographic characteristics and patient-reported outcomes including Knee Society scores, Western Ontario and McMaster Universities Arthritis Index, and forgotten joint score-12 were compared between the groups.

RESULTS

Statistically significant differences were observed in postoperative 2-year clinical outcomes in favor of RFA-TKA group which showed greater accuracy in the tibial component sagittal alignment than MA-TKA (1.0 ± 2.3 vs. 0.7 ± 1.6, respectively; P < 0.001). However, outliers in the component positions were more common in the MA-TKA group, which was statistically significant for the femoral coronal and tibial sagittal alignments (P = 0.017 and 0.015, respectively).

CONCLUSIONS

Functional alignment in TKA could be accurately obtained with the assistance of a robotic arm, and the results showed greater 2 year postoperative patient-reported outcome and satisfaction than mechanically aligned TKA using manual instruments.

LEVEL OF EVIDENCE

III.

Is sequential bilateral robotic total knee arthroplasty a safe procedure? A matched comparative pilot study

INTRODUCTION

To our knowledge, no papers have reported the results of robotic-assisted surgery for sequential bilateral Total Knee Arthroplasty (TKA). Indeed, sequential bilateral TKA present several benefits, as one single anesthesia, surgical episode, hospitalization, and rehabilitation. The purpose of our study was to evaluate peri-operative outcomes and compare the complication rates, clinical outcomes, and implant positioning of sequential bilateral TKA performed with a robotic-assisted system versus a conventional technique.

MATERIALS AND METHODS

All patients who underwent a sequential bilateral robotic-assisted primary TKA (raTKA) in our institution between November 2019 and February 2021 were included. Twenty patients met the inclusion criteria and were matched with 20 sequential bilateral TKA performed with a conventional technique. The two groups were comparable for the demographic data and the preoperative parameters, including preoperative anticoagulation and ASA score. The minimum follow-up was 6 months.

RESULTS

The operative time was significantly longer in the robotic group (< 0.0001), with a mean additional time of 29 min. There was no significant difference between both groups for postoperative blood loss, rate of blood transfusion, or postoperative pain. The average length of stay was 5 days. There was one early complication in the robotic group due to the tibial trackers. The functional outcomes were similar between both groups, except for the functional KSS score, which was better at 6 months in the robotic group (p < 0.0001). The restoration of the knee alignment and the distal femoral anatomy were significantly better in the robotic group than in the conventional group.

CONCLUSIONS

Despite a longer operative time, the peri-operative parameters of sequential bilateral TKA were similar between robotic and conventional techniques. Further, sequential bilateral raTKA was at least as safe as a conventional technique, without additional risk of medical complications.

Rehabilitation approach in robot assisted total knee arthroplasty: an observational study

BACKGROUND

The purpose of this study is to evaluate the impact of total knee arthroplasty (TKA) with the aid of Navio Robot, comparing it with standard prosthetic surgery on the functional outcomes of patients after an intensive rehabilitation program.

METHOD

A case-control observational study was conducted on patients undergoing TKA for severe KOA. All patients underwent the same intensive hospital rehabilitation program of 14 daily sessions lasting 3 h. The following rating scales were administered: Numeric Rating Scale (NRS), Knee Society Score (KSS) and 12-Item Short Form Survey scale. Patient assessments were performed 1 week post-surgery (T0), 1 month post-surgery (T2), and 3 months post-surgery (T3). The primary outcomes were active knee extension and flexion and pain severity. The secondary outcomes were functional capacity and quality of life.

RESULTS

Using repeated measures ANOVA, we observed at T1 a statistically different difference for the treatment group compared to the control group about KSS (p < 0.05), pain (p < 0.05), and knee flexion (p < 0.05). No statistically significant difference between the two groups was observed for knee extension (p = 0.09) and the SF-12 scale (p = 0.52). At T2 instead, we observed a statistically significant difference for the treatment group compared to the control group as regards KSS (p < 0.05) and knee flexion (p < 0.05), while no statistically significant difference was observed for pain (p = 0.83), knee extension (p = 0.60), and the SF-12 scale (0.44).

CONCLUSIONS

Our study has demonstrated that robot-NAVIO assisted knee prosthesis surgery, associated with a specific intensive rehabilitation treatment, in the short and medium term, determines good pain control, better flexion recovery and a improvement of functional capacity.

Is the femoral intramedullary alignment already actual in total knee arthroplasty?

Clinical outcomes and overall alignment after total knee arthroplasty (TKA) depend on femoral component positioning in the sagittal and the coronal plane, making choice of the distal femoral cutting guide crucial. Currently, there is no consensus on the potential advantage of an extramedullary (EM) guide compared to an intramedullary (IM) guide in TKA. The IM guide is the most widely used system for making the distal femoral cut although evidence for its superiority over the EM guide is lacking. However, inaccuracies arising with the IM guide include location of the rod entry point in the coronal plane, femoral canal diameter, femoral bowing, and structural features of the rod. Furthermore, the invasive procedure is associated with increased risk of postoperative blood loss, thromboembolic complications, and intraoperative fractures. While the EM guide has no such difficulties, its accuracy depends on the instruments used. Studies have reported results not inferior to the IM guide and a lower number of postoperative complications. Patient-specific instrumentation (PSI) and robotic and computer-assisted TKA have achieved excellent clinical and radiographic results and can overcome the problems inherent to the IM and the EM guide. Authors performed a systematic review of the literature and proposed a narrative review to summarize the characteristics of the IM and the EM guide and compare the advantages and disadvantages of each, as well as their limitations in comparison with new technologies. Authors also expressed their expert opinion.

Robotic Arm-Assisted versus Manual Total Knee Arthroplasty: A Propensity Score-Matched Analysis

The purpose of this study was to compare (1) operative time, (2) in-hospital pain scores, (3) opioid medication use, (4) length of stay (LOS), (5) discharge disposition at 90-day postoperative, (6) range of motion (ROM), (7) number of physical therapy (PT) visits, (8) emergency department (ED) visits, (9) readmissions, (10) reoperations, (11) complications, and (12) 1-year patient-reported outcome measures (PROMs) in propensity matched patient cohorts who underwent robotic arm-assisted (RA) versus manual total knee arthroplasty (TKA). Using a prospectively collected institutional database, patients who underwent RA- and manual TKA were the nearest neighbor propensity score matched 3:1 (255 manual TKA:85 RA-TKA), accounting for various preoperative characteristics. Data were compared using analysis of variance (ANOVA), Kruskal-Wallis, Pearson's Chi-squared, and Fisher's exact tests, when appropriate. Postoperative pain scores, opioid use, ED visits, readmissions, and 1-year PROMs were similar between the cohorts. Manual TKA patients achieved higher maximum flexion ROM (120.3 ± 9.9 versus 117.8 ± 10.2, p = 0.043) with no statistical differences in other ROM parameters. Manual TKA had shorter operative time (105 vs.113 minutes, p < 0.001), and fewer PT visits (median [interquartile range] = 10.0 [8.0-13.0] vs. 11.5 [9.5-15.5] visits, p = 0.014). RA-TKA had shorter LOS (0.48 ± 0.59 vs.1.2 ± 0.59 days, p < 0.001) and higher proportion of home discharges (p < 0.001). RA-TKA and manual TKA had similar postoperative complications and 1-year PROMs. Although RA-TKA patients had longer operative times, they had shorter LOS and higher propensity for home discharge. In an era of value-based care models and the steady shift to outpatient TKA, these trends need to be explored further. Long-term and randomized controlled studies may help determine potential added value of RA-TKA versus manual TKA. This study reflects level of evidence III.

The Accuracy of Computed Tomography-Based, Three-Dimensional Implant Planning in Robotic-Assisted Total Knee Arthroplasty

Advanced imaging used in robotic-assisted total knee arthroplasty (TKA), such as computed tomography (CT)-based three-dimensional (3D) planning, may provide an accurate means of implant sizing preoperatively. The purpose of this study was to examine preoperative CT-based implant planning accuracy for robotic-assisted TKA in patients who have (1) varus deformities, (2) valgus deformities, (3) neutral alignment, and (4) retained hardware. A total of 393 patients underwent a robotic-assisted TKA by a single surgeon received preoperative CT scans. The surgeon reviewed the CT-based model preoperatively and recorded the expected size of the components. The final implants used in each case were recorded and compared with the surgeon's preoperative plan. In all groups of patients, the surgeon's CT-based implant plan was within one size of the implant utilized 100% of the time for both the tibiae and femora. Overall, the surgeon was exactly matched in 319 (81%) and 315 (80%) cases for the femoral and tibial components, respectively. For the femoral component, the mean age for patients in whom the original plan was exactly matched was younger than those whose implants were upsized and older than patients those implants were downsized (p = 0.024). Other patient demographics and preoperative knee alignment were not associated with predictive accuracy for femoral or tibial components. Our results demonstrate how preoperative CT-based, 3D planning for robotic-assisted TKA is accurate to within one size of the components in every case (100%), and exactly matched in 80%. The results of this study are important because they demonstrate how CT-based preoperative implant planning for TKA is reliable and accurate across all native knee alignments and other patient-specific factors. In addition, they build on a previous study by the same single surgeon, demonstrating that predictive ability can improve over time. This may be important as we move toward more outpatient surgery with less ability for prostheses inventory at ambulatory sites.

Cost-effectiveness analysis of robotic-arm assisted total knee arthroplasty

PURPOSE

Total knee arthroplasty (TKA) is widely recognized as an effective treatment for end-stage knee osteoarthritis (OA). Compared with conventional TKA, robotic-arm assisted TKA may improve patients' functionality and resulting quality of life by more accurate and precise component placement. Currently, the literature on cost-effectiveness of robotic-arm assisted TKA in the US is limited. The objective of this study was to assess the cost-effectiveness of robotic-arm assisted TKA relative to TKA in the Medicare-aged population including exploring the impact of hospital volume on cost-effectiveness outcomes.

METHODS

We developed a decision-analytic model to evaluate the costs, health outcomes, and incremental cost-effectiveness ratio (ICER) of robotic-arm assisted TKA vs TKA in Medicare population with OA. We evaluated cost-effectiveness at a willingness-to-pay (WTP) threshold of $50,000 per quality-adjusted life-year (QALY). We sourced costs from the literature including episode-of-care (EOC) costs from a Medicare study. We assessed cost-effectiveness of robotic-arm assisted TKA by hospital procedure volume and conducted deterministic (DSA) and probabilistic sensitivity analysis (PSA).

RESULTS

For the average patient treated in a hospital with an annual volume of 50 procedures, robotic-arm assisted TKA resulted in a total QALY of 6.18 relative to 6.17 under conventional TKA. Total discounted costs per patient were $32,535 and $31,917 for robotic-arm assisted TKA and conventional TKA, respectively. Robotic-arm assisted TKA was cost-effective in the base case with an ICER of $41,331/QALY. In univariate DSA, cost-effectiveness outcomes were most sensitive to the annual hospital procedure volume. Robotic-arm assisted TKA was cost-effective at a WTP of $50,000/QALY only when hospital volume exceeded 49 procedures per year. In PSA, robotic-arm assisted TKA was cost-effective at a $50,000/QALY WTP threshold in 50.4% of 10,000 simulations.

CONCLUSIONS

Despite high robotic purchase costs, robotic-arm assisted TKA is likely to be cost-effective relative to TKA in the Medicare population with knee OA in high-volume hospitals through lowering revision rates and decreasing post-acute care costs. Higher-volume hospitals may deliver higher value in performing in robotic-arm assisted TKA.

Comparison of patient reported outcomes after robotic versus manual total knee arthroplasty in the same patient undergoing staged bilateral knee arthroplasty

Background

Robotic-assisted total knee arthroplasty (RATKA) has been proven to improve accuracy of component positioning and reducing alignment target outliers. However, the clinical benefit of robotics is often debated. Recent studies have shown reduced pain and faster recovery in the immediate post-operative period and may be associated with improved PROMs and satisfaction. The aim of this study was to assess PROMs and satisfaction in a unique patient population undergoing bilateral staged TKA to compare manual (MTKA) and RATKA in the same patient.

Methods

55 patients underwent bilateral staged TKA, performed by a single surgeon at a single institute. Patients who underwent TKA for the first knee with manual technique and RATKA for the second side, were eligible for inclusion in the study. Primary outcome assessed was the Oxford Knee Score and secondary outcomes included the Forgotten Joint Score (FJS), patient satisfaction, mean duration for independent ambulation after TKA, and patient perspectives on recovery evaluated with a questionnaire.

Results

Both RATKA and MTKA were associated with comparable PROMs. Though RATKA was associated with improved joint perception (Mean FJS after MTKA surgery was 70.3 (SD = 10.66) and significantly lower than the mean FJS after RATKA (73, SD = 10.95, p-value < 0.01), but the difference was not clinically relevant. A higher proportion of patients were more likely to be very satisfied or satisfied after RATKA. A significant proportion of patients felt the knee operated with RATKA was less painful and felt more natural compared to MTKA at final follow-up (p < 0.01). Majority of patients would undergo RATKA again and recommend robotic-TKA to others.

Conclusion

Robotic-assisted surgery was associated with improved patient satisfaction, faster independent ambulation compared to manual techniques. PROMs however, were comparable without clinically significant differences. Patients preferred robotic-assisted surgery, with a significantly higher proportion perceiving knee operated by RATKA felt more natural.

Is it prime time for robotic-assisted TKAs? A systematic review of current studies

Introduction

Less-than-optimum positioning of femoral and tibial components and improper soft tissue tension, with abnormal loads and reduced range of motion, may cause lower patient satisfaction rates. To reduce surgeon-related variables during TKA, technology-assisted TKA was introduced, including computer navigation and robotic-assisted surgery (RATKA). Although several studies show promising short- and long-term functional and radiological outcomes of RATKA, there are still concerns related to its absolute superiority over conventional TKA.

Methods

This review aims to provide an updated insight into the most recent articles reporting on outcomes (functional, radiological, and complications) of RATKA through a systematic search of major databases. A comprehensive English literature search was performed by both authors through four databases (Embase, PubMed, Web of Science, and Scopus). The full text of the final eligible studies was evaluated for inclusion, resulting in 13 studies that are included in this review.

Results

There were 2112 knees in the 13 studies, with a follow-up ranging from three months to 13 years; only three were randomized controlled trials (RCTs), and nine directly compared the results of RATKA with CTKA technique. Seven studies reported the operative time ranging from 76.8 to 156 min; six reported a longer operative time with RATKA. Length of hospital stay (LOS) was reported in six studies which ranged from 0.48 to 2.1 days; in four studies the LOS was shorter with RATKA. In seven of the nine studies comparing RATKA with CTKA, no difference in functional outcomes was found. Four out of six studies reported that the overall alignment had mechanical alignment within ±3° of neutral alignment in all RATKA patients with an HKA ranging from -0.3 to 1.8°. Only one study reported better radiological outcomes in the RATKA group. In six comparative studies, no difference was found in the incidence of complications between RATKA and CTKA.

Conclusion

Although robotic-assisted total knee arthroplasty is a promising technology that provides better component alignment and superior early functional outcomes, the justification for its widespread adoption needs more robust evidence through well-designed and better long-term studies demonstrating superior, predictable, and durable clinical results compared to conventional total knee arthroplasty techniques.

The evolution of robotic systems for total knee arthroplasty, each system must be assessed for its own value: a systematic review of clinical evidence and meta-analysis

INTRODUCTION

Robotic systems have been introduced to improve the precision of total knee arthroplasty. However, different robotic systems are available, each with unique features used to plan and execute the surgery. As such, due to this diversity, the clinical evaluation of each robotic platform should be separated.

METHODS

An extensive literature search of PubMed, Medline, Embase and Web of Science was conducted with subsequent meta-analysis. Randomised controlled trials, comparative studies, and cohort studies were included regarding robot-assisted total knee arthroplasty. Evaluated outcomes included clinical results, surgical precision, ligament balance, surgical time, learning curve, complications and revision rates. These were split up based on the robot-specific brand: ROBODOC (T-SOLUTION ONE), OMNIBOT, MAKO, NAVIO (CORI) and ROSA.

RESULTS

With a follow-up of more than 10 years, no improved clinical outcomes have been noted with the ROBODOC system compared to the conventional technique. If available, other platforms only present short-term clinical outcomes. Radiological outcomes are published for most robotic setups, demonstrating improved surgical precision compared to the conventional technique. Gap balance assessment is performed differently between all systems, leading to heterogeneous outcomes regarding its relationship on clinical outcomes. There is a similar learning curve based on operative time for all robotic platforms. In most studies, robot assistance requires longer operative time compared to the conventional technique. Complications and revision rates are published for ROBODOC and MAKO, without clear differences to conventional total knee arthroplasty.

CONCLUSION

The main finding of this systematic review is that the current evidence regarding each robotic system is diverse in quantity and quality. Each system has its own specificities and must be assessed for its own value. Regarding scientific literature, the generic term of robotic should be banned from the general conclusion.

LEVEL OF EVIDENCE

Systematic review level IV.

Use of intraoperative technology in total knee arthroplasty is not associated with reductions in postoperative pain

PURPOSE

Our systematic review and meta-analysis sought to assess how technology-assistance impacts (1) post-operative pain and (2) opioid use in patients undergoing primary total knee arthroplasty (TKA).

METHODS

Four online databases were queried for studies published up to October 2021 that reported on pain and opioid usage between technology-assisted and manual TKA (mTKA) patients. Mantel-Haenszel (M-H) models were utilized to calculate pooled mean difference (MDs) and 95% confidence interval (CIs). Subgroup analyses were conducted to isolate robotic-arm assisted (RAA) and computed-assisted navigation (CAN) cohorts. Risk of bias was assessed for all included non-randomized studies with the Methodological Index for Non-Randomized Studies (MINORS) tool. For the randomized control trials included in our study, the Detsky scale was applied.

RESULTS

Our analysis included 31 studies, reporting on a total of 761,300 TKAs (mTKA: n = 753,554; Computer-Assisted Navigation (CAN): n = 1,309; Robotic-Arm Assisted (RAA): n = 6437). No differences were demonstrated when evaluating WOMAC (MD: 0.00, 95% CI - 0.69 to 0.69; p = 1.00), KSS (MD: 0.01, 95% CI - 1.46 to 1.49; p = 0.99), KOOS (MD - 2.91, 95% CI - 6.17 to 0.34; p = 0.08), and VAS (MD - 0.54, 95% CI - 1.01 to - 0.007; p = 0.02) pain scores between cohorts. There was mixed evidence regarding how opioid consumption differed between TKA techniques.

CONCLUSION

The present analysis demonstrated no difference in terms of pain across a variety of utilized patient-reported pain measurements. However, there were mixed results regarding how opioid consumption varied between manual and technology-assisted cohorts, particularly in the immediate post-operative period.

LEVEL OF EVIDENCE

III.

A new robotically assisted technique can improve outcomes of total knee arthroplasty comparing to an imageless navigation system

BACKGROUND

Robotic assisted total knee arthroplasty (RTKA) has shown improved knee alignment and reduced radiographic outliers. However, there remains debate on functional outcomes and patient-reported outcomes (PROMs). This study compares the 1-year clinical outcomes of a new imageless robotically assisted technique (ROSA Knee System, Zimmer Biomet, Warsaw, IN) with an imageless navigated procedure (NTKA, iAssist Knee, Zimmer, Warsaw, IN).

METHODS

The study is a retrospective analysis of prospectively collected data that compared the functional outcomes and PROMs of 50 imageless RTKA with 47 imageless NTKA at 1-year follow-up. Baseline characteristics, intraoperative and postoperative information were collected including complications, revisions, Knee Society Score (KSS), Knee injury and Osteoarthritis Outcome Score (KOOS) score, and Forgotten Joint Score (FJS-12). Radiographic analysis of preoperative and postoperative images evaluating hip-knee-ankle (HKA) angle was performed.

RESULTS

There was no difference regarding baseline characteristics between the groups. Mean operative time was significantly longer in the RTKA group (122 min vs. 97 min; p < 0.0001). Significant differences were reported for the "Pain" (85 [RTKA] vs 79.1 [NTKA]; p = 0.0283) subsection of the KOOS score. In addition, RTKA was associated with higher maximum range of motion (119.4° vs. 107.1°; p < 0.0001) and better mean improvement of the arc of motion by 11.67° (23.02° vs. 11.36°; p < 0.0001). No significant differences were noted for other subsections of KOOS, KSS, FJS-12, complications, or limb alignment at 1-year follow-up.

CONCLUSIONS

Imageless RTKA was associated with longer surgical time, better pain perception and improved ROM at 12-month follow-up compared with NTKA. No significant differences were reported on other PROMs, complication rates and radiographic outcomes.

LEVEL OF EVIDENCE

III.

Robotic Versus Manual Total Knee Arthroplasty in High Volume Surgeons: A Comparison of Cost and Quality Metrics

BACKGROUND

Robotic-assisted total knee arthroplasty (RTKA) was introduced to improve surgical accuracy and patient outcomes. However, RTKA may also increase operating time and add cost to TKA. This study sought to compare the differences in cost and quality measures between manual TKA (MTKA) and RTKA METHODS: All MTKAs and RTKAs performed between January 1, 2017 and December 31, 2019, by 6 high volume surgeons in each cohort, were retrospectively reviewed. Cohorts were propensity score matched. Operative time, length of stay (LOS), total direct cost, 90-day complications, utilization of postacute services, and 30-day readmissions were studied.

RESULTS

After one-to-one matching, 2392 MTKAs and 2392 RTKAs were studied. In-room/out-of-room operating time was longer for RTKA (139 minutes) than for MTKA (107 minutes) P < .0001, as was procedure time (RTKA 78 minutes; MTKA 70 minutes), P < .0001. Median LOS was equal for MTKA and RTKA (33 hours). Total cost per case was greater for RTKA ($11,615) than MTKA ($8674), P < .0001. Home health care was utilized more frequently after RTKA (38%) than MTKA (29%), P < .0001. There was no significant difference in 90-day complication rates. Thirty-day readmissions occurred more often after MTKA (4.9%) than RTKA (1.2%), P < .0001.

CONCLUSION

RTKA was a longer and costlier procedure than MTKA for experienced surgeons, without clinically significant differences in LOS or complications. Home health care was utilized more often after RTKA, but fewer readmissions occurred after RTKA. Longer term follow-up and functional outcome studies are required to determine if the greater cost of RTKA is offset by lower revision rates and/or improved functional results.

Clinical results and patient-reported outcomes following robotic-assisted primary total knee arthroplasty : a multicentre study

Aims

The aim of this study was to report patient and clinical outcomes following robotic-assisted total knee arthroplasty (RA-TKA) at multiple institutions with a minimum two-year follow-up.

Methods

This was a multicentre registry study from October 2016 to June 2021 that included 861 primary RA-TKA patients who completed at least one pre- and postoperative patient-reported outcome measure (PROM) questionnaire, including Forgotten Joint Score (FJS), Knee Injury and Osteoarthritis Outcomes Score for Joint Replacement (KOOS JR), and pain out of 100 points. The mean age was 67 years (35 to 86), 452 were male (53%), mean BMI was 31.5 kg/m² (19 to 58), and 553 (64%) cemented and 308 (36%) cementless implants.

Results

There were significant improvements in PROMs over time between preoperative, one- to two-year, and > two-year follow-up, with a mean FJS of 17.5 (SD 18.2), 70.2 (SD 27.8), and 76.7 (SD 25.8; p < 0.001); mean KOOS JR of 51.6 (SD 11.5), 85.1 (SD 13.8), and 87.9 (SD 13.0; p < 0.001); and mean pain scores of 65.7 (SD 20.4), 13.0 (SD 19.1), and 11.3 (SD 19.9; p < 0.001), respectively. There were eight superficial infections (0.9%) and four revisions (0.5%).

Conclusion

RA-TKA demonstrated consistent clinical results across multiple institutions with excellent PROMs that continued to improve over time. With the ability to achieve target alignment in the coronal, axial, and sagittal planes and provide intraoperative real-time data to obtain balanced gaps, RA-TKA demonstrated excellent clinical outcomes and PROMs in this patient population.

Cite this article: Bone Jt Open 2022;3(7):589–595.

Robotic-assisted surgery and kinematic alignment in total knee arthroplasty (RASKAL study): a protocol of a national registry-nested, multicentre, 2×2 factorial randomised trial assessing clinical, intraoperative, functional, radiographic and survivorship outcomes

INTRODUCTION

Robot-assisted surgery (RAS) and kinematic alignment (KA) are being increasingly adopted to improve patient outcomes in total knee arthroplasty (TKA). There is uncertainty around the individual or combined effect of these concepts compared with computer-assisted surgery (CAS) and mechanical alignment (MA), respectively. This study aims to assess the effectiveness of RAS, KA or both to improve clinical outcomes, functional measures, radiographic precision and prosthetic survivorship when compared with current gold standards of surgical care.

METHODS AND ANALYSIS

A national registry-nested, multicentre, double-blinded, 2×2 factorial, randomised trial will be undertaken with 300 patients undergoing primary unilateral TKA performed by 15 surgeons. The primary outcome will be the between-group differences in postoperative change over 2 years in the mean Knee injury and Osteoarthritis Outcome Score (KOOS-12), comparing first, RAS to CAS as its control, and second, KA to MA as its control. Secondary outcomes will include other knee-specific and general health patient-reported outcome measures (PROMs), intraoperative pressure loads as a measure of soft tissue balance, 6-month postoperative functional outcomes, radiological precision using CT imaging, complications and long-term prosthetic survivorship. The contribution of each patient's unique coronal plane alignment of the knee phenotype to primary and secondary PROMs will be investigated. OMERACT-OARSI criteria and Patient Acceptable Symptom State outcome score thresholds for the KOOS-12 and Oxford Knee Score will be used in secondary analyses. Primary intention-to-treat and secondary per-protocol analyses will be performed. Statistical analysis will include a generalised linear mixed model for repeated measures for continuous KOOS-12 scores. Kaplan-Meier estimates with adjusted HRs of implant survivorship will be calculated.

ETHICS AND DISSEMINATION

Ethics approval was obtained from Sydney Local Health District-Royal Prince Alfred Hospital (Approval X20-0494 and 2020/ETH02896 10.24/DEC20). Results will be submitted for publication in a peer-reviewed journal and presented in national, state and international meetings.

TRIAL REGISTRATION NUMBER

ACTRN12621000205831.

Robot-assisted Knee Arthroplasty: Randomized Clinical Trial

BACKGROUND: Osteoarthritis of the knee joint leads to a decrease in the volume of movements, a violation of the sliding of articular surfaces, and a change in the axis of the limb under load, which affects the biomechanics of walking. AIM: This study aims to compare the results of robot-assisted total knee arthroplasty (TKA) and manual techniques, their influence on the biomechanical and podometric parameters of the patient’s walk. METHODS: A prospective randomized study of 68 patients was carried out in the period from 2020 to 2021. Our follow-up period was 1 year. All patients were performed arthroplasty of one knee joint. The main Group “A” included 33 patients TKA with the use of an active robotic setting “TSolution-One” (“THINK Surgical, Inc.” [Fremont, California, USA]); the comparison Group “B” consisted of 35 patients with manual technic of TKA. We studied pain syndrome on the visual analog scale, functional state on the Oxford Knee Score (OKS) and Western Ontario and McMaster Universities Arthritis Index (WOMAC), the volume of ROM movements, and the deviation of the mechanical axis by teleroentgenography of the lower limb. Objective analysis of limb function was performed on the «Alter-G» and the «C-mill». RESULTS: Post-operative pain syndrome on the 1st day after surgery in Group A is stronger by 7.9%, but by the 5th day after surgery in Group A, the pain syndrome is lower by 14.3%. ROM in Group A is better by 16% by 3 months after surgery, after 1 year by 10%. The positioning accuracy of the implant in Group A is 30% better. There are no statistically significant differences in the OKS and WOMAC scales between the groups. The results of restoring normal step in Group A are 13.5% better than in Group B. CONCLUSIONS: Robot-assisted TKA gives more accurate alignment of the mechanical axis, which improves the biomechanics of walking.

Improved Component Placement Accuracy with Robotic-Arm Assisted Total Knee Arthroplasty

Component position of total knee arthroplasty (TKA) has been shown to influence prosthetic survivorships and clinical outcomes. Our objective was to compare the three-dimensional accuracy to plan of robotic-arm assisted TKA (RATKA) with conventional TKA for component position. We conducted a nonrandomized, prospective study comparing 143 RATKA with 86 conventional TKA operated at four U.S. centers between July 2016 and October 2018. Computed tomography (CT) scans obtained approximately 6 weeks postoperatively were analyzed using anatomical landmarks. Absolute deviation from surgical plans were defined as the absolute value of the difference between the CT measurements and surgeons' femoral and tibial component mechanical varus/valgus alignment, tibial component posterior slope, and femoral component internal/external rotation. Differences of absolute deviations were tested using stratified Wilcoxon's tests that controlled for study center. Patient-reported outcome measures collected through 1 postoperative year were modeled using multiple regression controlling for age, sex, body mass index, study center, and the preoperative score. RATKA demonstrated greater accuracy for tibial component alignment (median [25th, 75th percentiles] absolute deviation from plan of all centers combined for conventional vs. RA, 1.7 [0.9, 2.9] vs. 0.9 [0.4, 1.9] degrees, p < 0.001), femoral component rotation (1.5 [0.9, 2.5] vs. 1.3 [0.6, 2.5] degrees, p = 0.015), and tibial slope (2.9 [1.5, 5.0] vs. 1.1 [0.6, 2.0] degrees, p < 0.001). In multivariable analyses, RATKA showed significantly greater Veterans RAND 12-item health survey (VR-12) physical component scores (adjusted mean difference [95% confidence interval (CI)]: 2.4 [0.2, 4.5] points, p = 0.034) and qualitatively greater Knee Society (KS) composite functional scores (3.5 [-1.3, 8.2] points, p = 0.159), though not statistically significant. Compared with conventional instrumentation, RATKA demonstrated greater three-dimensional accuracy to plan for various component positioning parameters and clinical improvements in physical status and function with no major safety concerns during the first postoperative year. These results may be attributed to the preoperative CT scan planning, real-time intraoperative feedback, and stereotactic-guided cutting that takes into consideration patient-specific bony anatomy. These findings support the use of RATKA for enhanced arthroplasty outcomes.

Rate and Timing of Return to Golf After Hip, Knee, or Shoulder Arthroplasty: A Systematic Review and Meta-analysis

BACKGROUND

The physical and mental health benefits of golf are well recognized, and as a moderate-intensity activity, it is an ideal sport for patients after joint arthroplasty.

PURPOSE

To assess the rate and timing of returning to golf and the factors associated with these after hip, knee, or shoulder arthroplasty.

STUDY DESIGN

Meta-analysis; Level of evidence, 4.

METHODS

A search of PubMed and Medline was performed in March 2021 in line with the 2009 PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. Search terms included sport, golf, and arthroplasty. The criterion for inclusion was any published research article studying return to golf after arthroplasty. Random-effects modeling was used to measure rates of returning to golf for each type of arthroplasty.

RESULTS

A total of 23 studies were included for review. All studies were retrospective in their methodology. The mean age of patients was 66.8 years (SD, 3.37). Four studies reported on hip arthroplasty, 6 on knee arthroplasty, and 13 on shoulder arthroplasty. Among 13 studies, the mean rate of returning to golf was 80% (95% CI, 70%-89.9%). Hip, knee, and shoulder arthroplasty had mean return rates of 90% (95% CI, 82%-98%), 70% (95% CI, 39%-100%), and 80% (95% CI, 68%-92%), respectively. Among 9 studies, the mean time to return to golf was 4.4 months (95% CI, 3.2-6). Change in handicap was reported in 8 studies (35%) with a mean change of -0.1 (95% CI, -2.4 to +2.2). There were no studies presenting factors associated with return to golf.

CONCLUSION

This is the first meta-analysis of returning to golf after joint arthroplasty. The study reports a high rate of returning to golf, which was greatest after hip arthroplasty. However, the study highlights the paucity of prospective data on demographic, surgical, and golf-specific outcomes after arthroplasty. Future prospective studies are required to eliminate response bias and accurately capture golf and patient-specific outcomes.

Robotic-arm assisted total knee arthroplasty is associated with improved accuracy and patient reported outcomes: a systematic review and meta-analysis

This systematic review and meta-analysis were conducted to compare the accuracy of component positioning, alignment and balancing techniques employed, patient-reported outcomes, and complications of robotic-arm assisted total knee arthroplasty (RATKA) with manual TKA (mTKA) and the associated learning curve. Searches of PubMed, Medline and Google Scholar were performed in October 2020 using PRISMA guidelines. Search terms included "robotic", "knee" and "arthroplasty". The criteria for inclusion were published clinical research articles reporting the learning curve for RATKA and those comparing the component position accuracy, alignment and balancing techniques, functional outcomes, or complications with mTKA. There were 198 articles identified, following full text screening, 16 studies satisfied the inclusion criteria and reported the learning curve of rTKA (n=5), component positioning accuracy (n=6), alignment and balancing techniques (n=7), functional outcomes (n=7), or complications (n=5). Two studies reported the learning curve using CUSUM analysis to establish an inflexion point for proficiency which ranged from 7 to 11 cases and there was no learning curve for component positioning accuracy. The meta-analysis showed a significantly lower difference between planned component position and implanted component position, and the spread was narrower for RATKA compared with the mTKA group (Femur coronal: mean 1.31, 95% confidence interval (CI) 1.08-1.55, p<0.00001; Tibia coronal: mean 1.56, 95% CI 1.32-1.81, p<0.00001). Three studies reported using different alignment and balancing techniques between mTKA and RATKA, two studies used the same for both group and two studies did not state the methods used in their RATKA groups. RATKA resulted in better Knee Society Score compared to mTKA in the short-to-mid-term follow up (95%CI [- 1.23,  - 0.51], p=0.004). There was no difference in arthrofibrosis, superficial and deep infection, wound dehiscence, or overall complication rates. RATKA demonstrated improved accuracy of component positioning and patient-reported outcomes. The learning curve of RATKA for operating time was between 7 and 11 cases. Future well-powered studies on RATKAs should report on the knee alignment and balancing techniques utilised to enable better comparisons on which techniques maximise patient outcomes.Level of evidence III.

How Does Robotic-Arm Assisted Technology Influence Total Knee Arthroplasty Implant Placement for Surgeons in Fellowship Training?

Implant malalignment during total knee arthroplasty (TKA) may lead to suboptimal postoperative outcomes. Accuracy studies are typically performed with experienced surgeons; however, it is important to study less experienced surgeons when considering teaching hospitals where younger surgeons operate. Therefore, this study assessed whether robotic-arm assisted TKA (RATKA) allowed for more accurate and precise implant position to plan when compared with manual techniques when the surgery is performed by in-training orthopaedic surgical fellows. Two surgeons, currently in their fellowship training and having minimal RATKA experience, performed a total of six manual TKA (MTKA) and six RATKAs on paired cadaver knees. Computed tomography scans were obtained for each knee pre- and postoperatively. These scans were analyzed using a custom autosegmentation and autoregistration process to compare postoperative implant position with the preoperative planned position. Mean system errors and standard deviations were compared between RATKA and MTKA for the femoral component for sagittal, coronal, and axial planes and for the tibial component in the sagittal and coronal planes. A 2-Variance testing was performed using an α = 0.05. Although not statistically significant, RATKA was found to have greater accuracy and precision to plan than MTKA for: femoral axial plane (1.1° ± 1.1° vs. 1.6° ± 1.3°), coronal plane (0.9° ± 0.7° vs. 2.2° ± 1.0°), femoral sagittal plane (1.5° ± 1.3° vs. 3.1° ± 2.1°), tibial coronal plane (0.9° ± 0.5° vs. 1.9° ± 1.3°), and tibial sagittal plane (1.7° ± 2.6° vs. 4.7° ± 4.1°). There were no statistical differences between surgical groups or between the two surgeons performing the cases. With limited RATKA experience, fellows showed increased accuracy and precision to plan for femoral and tibial implant positions. Furthermore, these results were comparable to what has been reported for an experienced surgeon performing RATKA.

Clinical and radiological outcomes of robotic-assisted unicompartmental knee arthroplasty: Early lessons from the first 100 consecutive knees in 85 patients

INTRODUCTION

Robotic-assisted unicompartmental knee arthroplasty (UKA) is associated with improved component positioning and comparable short- and mid-term implant survivorship with manual UKA. This study aims to evaluate clinical and radiological outcomes following robotic-assisted UKA as well as any potential learning-curves associated with the introduction of such new technology.

METHODS

Prospective study of patients undergoing robotic-assisted UKA. Outcome measures were patient-reported outcome measures (PROMs) including Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Society Score (KSS) and Oxford Knee Score (OKS), complications, implant survivorship, component positioning and learning curve.

RESULTS

Eighty-five patients comprising 100 knees were recruited and followed up for 21.0 ± 4.3 months. At two years, there were significant and sustained improvements in PROMs and 100% implant survivorship rate. A high degree of implant accuracy was achieved with the robotic system. A cumulative learning curve of 20 cases was noted.

CONCLUSION

Robotic-assisted UKA achieves excellent implant accuracy and clinical outcomes in the short-term. Long-term follow up is needed to evaluate this relationship.

MAKO CT-based robotic arm-assisted system is a reliable procedure for total knee arthroplasty: a systematic review

PURPOSE

The aim of this study was to investigate the clinical and radiological results of the MAKO CT-based robotic-assisted system for total knee arthroplasty (TKA).

METHODS

A PRISMA systematic review was conducted using four databases (MEDLINE, EMBASE, Pubmed, GOOGLE SCHOLAR) to identify all clinical and radiological studies reporting information regarding the use and results of the CT-based robotic-assisted system to perform TKA between 2016 and 2020. The main investigated outcome criteria were postoperative pain, analgesia requirements, clinical scores, knee range of motion, implant positioning and the revision rate. The ROBINS-I tool (Risk Of Bias In Non-randomized Studies of Interventions) was used to evaluate the quality of included studies and the risk of bias.

RESULTS

A total of 36 studies were identified, of which 26 met inclusion criteria. Of these 26 studies, 14 were comparative. The follow-up varied from 30 days to 17 months. This CT-based, saw cutting Robotic TKA is associated with a significantly lower postoperative pain score (2.6 versus 4.5) and with significantly reduced time to hospital discharge (77 h versus 105), compared with conventional TKA. The two comparative studies assessing functional outcomes at 1 year reported significantly better functional scores with CT-based robotic TKA compared with conventional TKA (WOMAC score: 6 ± 6 versus 9 ± 8 (p < 0.05); KSS function score: 80 versus 73 (p = 0.005)). Only three comparative studies assessed implant positioning, and these reported better implant positioning with CT-based robotic-assisted TKA.

CONCLUSION

The CT-based robotic-assisted system for TKA reduced postoperative pain and improved implant positioning with equal or slightly superior improvement of the functional outcomes at one year, compared to conventional TKA.

LEVEL OF EVIDENCE

Systematic review level IV.

Patient Satisfaction Following Primary Total Knee Arthroplasty: Contributing Factors

The reported dissatisfaction rate after primary total knee arthroplasty (TKA) ranges between 15% and 25%. The purpose of this article is to perform a narrative review of the literature with the aim of answering the following question: What are the main factors contributing to patient dissatisfaction after TKA? A review of the literature was performed on patient satisfaction after TKA. The search engines used were MedLine (PubMed) and the Cochrane Library. The keywords used were "TKA" and "satisfaction". The main reported preoperative factors positively contributing to patient satisfaction were the following: fulfilment of preoperative expectations, preoperative complete joint space collapse, increasing patellar and lateral compartment osteophyte size, and TKA communication checklist. The principal preoperative factors negatively contributing to patient satisfaction included female sex, comorbidities, and Hispanic race. The chief perioperative factor positively contributing to patient satisfaction was cosmetic closure, whereas the fundamental perioperative factors negatively contributing to patient satisfaction included joint laxity, anterior tibial component slope, and greater femoral component valgus angle. The principal postoperative factors positively contributing to patient satisfaction were the following: ameliorated walking distance, improved range of motion, and improvements in pain. The most important postoperative factors negatively contributing to patient satisfaction included poor postoperative knee stability and soft-tissue balance, functional limitation, surgical complication and reoperation, staff or quality of care issues, and increased stiffness.

Safe and effective use of active robotics for TKA: Early results of a multicenter study

Background

A novel active robotic system for total knee arthroplasty (TKA) performs automated milling of bone surfaces. Study objectives were to assess system safety and effectiveness in a US population.

Methods

A multicenter clinical trial was conducted, following 115 patients for at least 6-months. A pre-defined list of robot-related adverse events was used to evaluate safety. Efficacy was assessed radiographically comparing planned versus achieved coronal limb alignment.

Results

No pre-defined adverse events occurred and postoperative limb alignment more than ±3° from plan occurred in 11.2 % of cases.

Conclusion

Active robotics for TKA is safe and effective as demonstrated in this trial.

Clinical outcomes associated with robotic and computer-navigated total knee arthroplasty: a machine learning-augmented systematic review

BACKGROUND

Robotic (RTKA) and computer-navigated total knee arthroplasty (CNTKA) are increasingly replacing manual techniques in orthopaedic surgery. This systematic review compared clinical outcomes associated with RTKA and CNTKA and investigated the utility of natural language processing (NLP) for the literature synthesis.

METHODS

A comprehensive search strategy was implemented. Results of included studies were combined and analysed. A transfer learning approach was applied to train deep NLP classifiers (BERT, RoBERTa and XLNet), with cross-validation, to partially automate the systematic review process.

RESULTS

52 studies were included, comprising 5,067 RTKA and 2,108 CNTKA. Complication rates were 0-22% and 0-16% and surgical time was 70-116 and 77-102 min for RTKA and CNTKA, respectively. Technical failures were more commonly associated with RTKA (8%) than CNTKA (2-4%). Patient satisfaction was equivalent (94%). RTKA was associated with a higher likelihood of achieving target alignment, less femoral notching, shorter operative time and shorter length of stay. NLP models demonstrated moderate performance (AUC = 0.65-0.68).

CONCLUSIONS

RTKA and CNTKA appear to be associated with similarly positive clinical outcomes. Further work is required to determine whether the two techniques differ significantly with regard to specific outcome measures. NLP shows promise for facilitating the systematic review process.

Robotic-assisted total knee arthroplasty improves accuracy and precision compared to conventional techniques

AIMS

Robotic-assisted total knee arthroplasty (RA-TKA) is theoretically more accurate for component positioning than TKA performed with mechanical instruments (M-TKA). Furthermore, the ability to incorporate soft-tissue laxity data into the plan prior to bone resection should reduce variability between the planned polyethylene thickness and the final implanted polyethylene. The purpose of this study was to compare accuracy to plan for component positioning and precision, as demonstrated by deviation from plan for polyethylene insert thickness in measured-resection RA-TKA versus M-TKA.

METHODS

A total of 220 consecutive primary TKAs between May 2016 and November 2018, performed by a single surgeon, were reviewed. Planned coronal plane component alignment and overall limb alignment were all 0° to the mechanical axis; tibial posterior slope was 2°; and polyethylene thickness was 9 mm. For RA-TKA, individual component position was adjusted to assist gap-balancing but planned coronal plane alignment for the femoral and tibial components and overall limb alignment remained 0 ± 3°; planned tibial posterior slope was 1.5°. Mean deviations from plan for each parameter were compared between groups for positioning and size and outliers were assessed.

RESULTS

In all, 103 M-TKAs and 96 RA-TKAs were included. In RA-TKA versus M-TKA, respectively: mean femoral positioning (0.9° (SD 1.2°) vs 1.7° (SD 1.1°)), mean tibial positioning (0.3° (SD 0.9°) vs 1.3° (SD 1.0°)), mean posterior tibial slope (-0.3° (SD 1.3°) vs 1.7° (SD 1.1°)), and mean mechanical axis limb alignment (1.0° (SD 1.7°) vs 2.7° (SD 1.9°)) all deviated significantly less from the plan (all p < 0.001); significantly fewer knees required a distal femoral recut (10 (10%) vs 22 (22%), p = 0.033); and deviation from planned polyethylene thickness was significantly less (1.4 mm (SD 1.6) vs 2.7 mm (SD 2.2), p < 0.001).

CONCLUSION

RA-TKA is significantly more accurate and precise in planning both component positioning and final polyethylene insert thickness. Future studies should investigate whether this increased accuracy and precision has an impact on clinical outcomes. The greater accuracy and reproducibility of RA-TKA may be important as precise new goals for component positioning are developed and can be further individualized to the patient. Cite this article: Bone Joint J 2021;103-B(6 Supple A):74-80.

The Use of Computer Navigation and Robotic Technology in Complex Total Knee Arthroplasty

»

The potential benefits of computer-assisted surgical (CAS) navigation and robotic total knee arthroplasty (TKA) systems, such as increased reliability of restoring the mechanical axis, fewer outliers, more rapid hospital discharge, less physical therapy requirements, decreased blood loss, and decreased revision rates, have led to their application not only in primary cases but also in complex cases such as preoperative deformity and revision.

»

Early evidence demonstrates that CAS navigation may help to improve alignment in complex cases of femoral and tibial deformity and in cases of femoral bowing.

»

Data regarding deformity correction with robotic systems are similar to CAS navigation with regard to alignment, but are more limited. There are also scant data regarding revision cases and cases of previous intramedullary canal instrumentation.

»

Concerns remain regarding cost, learning curves, and operative times. There are potential long-term cost savings associated with a decrease in revisions and readmissions that require additional investigation.

»

Early evidence for the use of these emerging technologies for deformity correction and revision cases is promising, but their impact on long-term functional outcomes remains to be demonstrated. Additional well-designed comparative studies are warranted.

The current state of robotics in total knee arthroplasty

Robotic total knee arthroplasty (TKA) has demonstrated improved component positioning and a reduction of alignment outliers with regard to pre-operative planning.

Early robotic TKA technologies were mainly active systems associated with significant technical and surgical complications.

Current robotic TKA systems are predominantly semi-active with additional haptic feedback which minimizes iatrogenic soft tissue injury compared to conventional arthroplasty and older systems.

Semi-active systems demonstrate advantages in terms of early functional recovery and hospital discharge compared to conventional arthroplasty.

Limitations with current robotic technology include high upfront costs, learning curves and lack of long-term outcomes.

The short-term gains and greater technical reliability associated with current systems may justify the ongoing investment in robotic technology.

Further long-term data are required to fully ascertain the cost-effectiveness of newer robotic systems.

Cite this article: EFORT Open Rev 2021;6:270-279. DOI: 10.1302/2058-5241.6.200052

A clinical review of robotic navigation in total knee arthroplasty: historical systems to modern design

Robotic-assisted total knee arthroplasty (RA-TKA) has shown improved reproducibility and precision in mechanical alignment restoration, with improvement in early functional outcomes and 90-day episode of care cost savings compared to conventional TKA in some studies. However, its value is still to be determined.

Current studies of RA-TKA systems are limited by short-term follow-up and significant heterogeneity of the available systems.

In today’s paradigm shift towards an increased emphasis on quality of care while curtailing costs, providing value-based care is the primary goal for healthcare systems and clinicians. As robotic technology continues to develop, longer-term studies evaluating implant survivorship and complications will determine whether the initial capital is offset by improved outcomes.

Future studies will have to determine the value of RA-TKA based on longer-term survivorships, patient-reported outcome measures, functional outcomes, and patient satisfaction measures.

Cite this article: EFORT Open Rev 2021;6:252-269. DOI: 10.1302/2058-5241.6.200071

Health Care Utilization and Payer Cost Analysis of Robotic Arm Assisted Total Knee Arthroplasty at 30, 60, and 90 Days

This study performed a health care utilization analysis between robotic arm assisted total knee arthroplasty (rTKA) and manual total knee arthroplasty (mTKA) techniques. Specifically, we compared (1) index costs and (2) discharge dispositions, as well as (3) 30-day (4) 60-day, and (5) 90-day (a) episode-of-care costs, (b) postoperative health care utilization, and (c) readmissions. The 100% Medicare Standard Analytical Files were used for rTKAs and mTKAs performed between January 1, 2016, and March 31, 2017. Based on strict inclusion-exclusion criteria and 1:5 propensity score matching, 519 rTKA and 2,595 mTKA patients were analyzed. Total episode payments, health care utilization, and readmissions, at 30-, 60-, and 90-day time points were compared using generalized linear model, binomial regression, log link, Mann-Whitney, and Pearson's chi-square tests. The rTKA versus mTKA cohort average total episode payment was US$17,768 versus US$19,899 (p < 0.0001) at 30 days, US$18,174 versus US$20,492 (p < 0.0001) at 60 days, and US$18,568 versus US$20,960 (p < 0.0001) at 90 days. At 30 days, 47% fewer rTKA patients utilized skilled nursing facility (SNF) services (13.5 vs. 25.4%; p < 0.0001) and had lower SNF costs at 30 days (US$6,416 vs. US$7,732; p = 0.0040), 60 days (US$6,678 vs. US$7,901, p = 0.0072), and 90 days (US$7,201 vs. US$7,947, p = 0.0230). rTKA patients also utilized fewer home health visits and costs at each time point (p < 0.05). Additionally, 31.3% fewer rTKA patients utilized emergency room services at 30 days postoperatively and had 90-day readmissions (5.20 vs. 7.75%; p = 0.0423). rTKA is associated with lower 30-, 60-, and 90-day postoperative costs and health care utilization. These results are of marked importance given the emphasis to contain and reduce health care costs and provide initial economic insights into rTKA with promising results.

Not All Robotic-assisted Total Knee Arthroplasty Are the Same

Because value in healthcare has shifted to a measurement of quality relative to the cost, a greater emphasis exists on improving clinical and functional outcomes and patient satisfaction. Despite advances in implant design, surgical technique, and postoperative rehabilitation, multiple studies demonstrate that nearly 20% of patients remain dissatisfied with their overall outcomes after primary total knee arthroplasty (TKA). Because implant positioning, alignment, and equal soft-tissue balance are critical for a successful TKA, malalignment in the coronal, sagittal, and rotational planes continue to increase failure rates and cause poor clinical outcomes. Robotic-assisted TKA has gained momentum within the past 10 years to better control surgical variables by mitigating technical errors caused by insecure cutting guides and imprecise bone cuts. Contemporary robotic platforms have evolved along with our ability to collect high-quality patient-reported outcome measures data, and this combination is proving the clinical effectiveness. This comprehensive review investigates the advent of robotic-assisted TKA including advantages, disadvantages, historical, and commercially available newer generation systems, clinical outcomes, and cost analysis to better understand the potential added value of this technology.

New Technologies in Knee Arthroplasty: Current Concepts

Total knee arthroplasty (TKA) is an effective treatment for severe osteoarthritis. Despite good survival rates, up to 20% of TKA patients remain dissatisfied. Recently, promising new technologies have been developed in knee arthroplasty, and could improve the functional outcomes. The aim of this paper was to present some new technologies in TKA, their current concepts, their advantages, and limitations. The patient-specific instrumentations can allow an improvement of implant positioning and limb alignment, but no difference is found for functional outcomes. The customized implants are conceived to reproduce the native knee anatomy and to reproduce its biomechanics. The sensors have to aim to give objective data on ligaments balancing during TKA. Few studies are published on the results at mid-term of these two devices currently. The accelerometers are smart tools developed to improve the TKA alignment. Their benefits remain yet controversial. The robotic-assisted systems allow an accurate and reproducible bone preparation due to a robotic interface, with a 3D surgical planning, based on preoperative 3D imaging or not. This promising system, nevertheless, has some limits. The new technologies in TKA are very attractive and have constantly evolved. Nevertheless, some limitations persist and could be improved by artificial intelligence and predictive modeling.

Robotic-assisted total knee arthroplasty is comparable to conventional total knee arthroplasty: a meta-analysis and systematic review

BACKGROUND

Total knee arthroplasty (TKA) is a successful procedure in managing end-stage arthritis when non-operative treatments fail. New technologies such as robotic TKA (rTKA) have been developed to improve the accuracy of prosthesis implantation. While short-term cohort studies on rTKA have shown excellent results, the evidence comparing between rTKA and conventional TKA (cTKA) is not yet well established. This meta-analysis aims to compare the efficacy and safety of rTKA versus cTKA in terms of clinical outcomes, radiographic results, complications, peri-operative parameters and costs.

METHODS

A multi-database search was performed according to PRISMA guidelines. Data from studies comparing between rTKA and cTKA were extracted and analyzed.

RESULTS

Eighteen studies were included in this review, consisting of 2234 rTKA and 4300 cTKA. Robotic TKA led to a more precise prosthesis implantation with significantly fewer outliers in the mechanical axis (p < 0.001), femoral coronal (p = 0.002) and tibial sagittal (p = 0.01) alignments. Only the Hospital for Special Surgery (HSS) (p < 0.001) score at final follow-up was significantly better in rTKA than cTKA. rTKA also had a lower mean blood loss (p < 0.001) despite a longer mean operation time (p = 0.006). There were no statistically significant difference in terms of other clinical outcome measures, range of motion and complications.

CONCLUSION

Both rTKA and cTKA are reliable and safe to perform. However, rTKA is capable of achieving superior alignment in several axes, lower mean blood loss and this may lead to marginally better clinical outcomes than cTKA.

EVIDENCE LEVEL

Level II, Meta-analysis of non-homogeneous studies.

Robotic Arm-Assisted Total Knee Arthroplasty in the Setting of Combined Extra-articular Deformities of the Femur and Tibia

In this case, we will describe a 68-year-old man with combined femoral and tibial bone deformities who underwent robotic arm-assisted total knee arthroplasty (RATKA) to treat his severe osteoarthritis in the setting of extra-articular deformities that altered the native anatomical axis and the kinematics of the deformed extra-articular bony structures which chronically generated a neomechanical axis. The combination of severe osteoarthritis with extra-articular deformities made the RATKA method the best surgical treatment option taking into account altered kinematics of the native joint which conventional jig-based total knee arthroplasty would not have prioritized during bony cuts and implant positioning. The patient underwent successful knee arthroplasty with robotic arm-assisted technology with restoration of the mechanical axis.

What are the benefits of robotic-assisted total knee arthroplasty over conventional manual total knee arthroplasty? A systematic review of comparative studies

Total knee arthroplasty (TKA) is a highly successful operation that improves patients' quality of life and functionality. Yet, up to 20% of TKA patients remain unsatisfied with the functional outcomes. Robotic TKA has gained increased attention and popularity in order to improve patient satisfaction and implant survivorship by increasing accuracy and precision of component implantation. The current systematic review was run in order to compare implant survivorship, complication rates, clinical outcomes, and radiological outcomes between robotic-assisted TKA (RA) and conventional manual TKA (CM). Articles were referenced from the US National Library of Medicine (PubMed/MEDLINE), EMBASE, and the Cochrane Database of Systematic Reviews. Nine comparative studies with 1199 operated knees in 1159 patients were included, 614 underwent active or semiactive robotic-assisted TKA compared to 585 CM-TKA. Improvements in the RA group were reported for early functional outcomes, radiographic outliers (RA 16% vs CM 76%) and radiolucent lines (RA 0% vs CM 35%). No significant differences between the two groups were reported in overall survivorship (RA 98.3% vs CM 97.3%), complication rate (RA 2.4% vs CM 1.4%) and operative time (RA 88 min vs CM 79 min). Despite higher costs, roboticassisted TKA offers better short-term clinical outcomes when compared to conventional manual technique with reduction in radiographic outliers and reduced risks of iatrogenic soft tissues injuries (reduced blood loss and postoperative drainage). Further high-quality long-term studies of modern robotic systems are required in order to evaluate how the increased accuracy and reduced outliers affect the long-term survivorship of the implants and the clinical outcomes.

Less iatrogenic soft-tissue damage utilizing robotic-assisted total knee arthroplasty when compared with a manual approach: A blinded assessment

Objectives

The use of the haptically bounded saw blades in robotic-assisted total knee arthroplasty (RTKA) can potentially help to limit surrounding soft-tissue injuries. However, there are limited data characterizing these injuries for cruciate-retaining (CR) TKA with the use of this technique. The objective of this cadaver study was to compare the extent of soft-tissue damage sustained through a robotic-assisted, haptically guided TKA (RATKA) versus a manual TKA (MTKA) approach.

Methods

A total of 12 fresh-frozen pelvis-to-toe cadaver specimens were included. Four surgeons each prepared three RATKA and three MTKA specimens for cruciate-retaining TKAs. A RATKA was performed on one knee and a MTKA on the other. Postoperatively, two additional surgeons assessed and graded damage to 14 key anatomical structures in a blinded manner. Kruskal–Wallis hypothesis tests were performed to assess statistical differences in soft-tissue damage between RATKA and MTKA cases.

Results

Significantly less damage occurred to the PCLs in the RATKA versus the MTKA specimens (p < 0.001). RATKA specimens had non-significantly less damage to the deep medial collateral ligaments (p = 0.149), iliotibial bands (p = 0.580), poplitei (p = 0.248), and patellar ligaments (p = 0.317). The remaining anatomical structures had minimal soft-tissue damage in all MTKA and RATKA specimens.

Conclusion

The results of this study indicate that less soft-tissue damage may occur when utilizing RATKA compared with MTKA. These findings are likely due to the enhanced preoperative planning with the robotic software, the real-time intraoperative feedback, and the haptically bounded saw blade, all of which may help protect the surrounding soft tissues and ligaments.

Cite this article: Bone Joint Res 2019;8:495–501.

Robotic technology in total knee arthroplasty: a systematic review

Robotic total knee arthroplasty (TKA) improves the accuracy of implant positioning and reduces outliers in achieving the planned limb alignment compared to conventional jig-based TKA.Robotic TKA does not have a learning curve effect for achieving the planned implant positioning. The learning curve for achieving operative times comparable to conventional jig-based TKA is 7-20 robotic TKA cases.Cadaveric studies have shown robotic TKA is associated with reduced iatrogenic injury to the periarticular soft tissue envelope compared to conventional jig-based TKA.Robotic TKA is associated with decreased postoperative pain, enhanced early functional rehabilitation, and decreased time to hospital discharge compared to conventional jig-based TKA. However, there are no differences in medium- to long-term functional outcomes between conventional jig-based TKA and robotic TKA.Limitations of robotic TKA include high installation costs, additional radiation exposure, learning curves for gaining surgical proficiency, and compatibility of the robotic technology with a limited number of implant designs.Further higher quality studies are required to compare differences in conventional TKA versus robotic TKA in relation to long-term functional outcomes, implant survivorship, time to revision surgery, and cost-effectiveness. Cite this article: EFORT Open Rev 2019;4:611-617. DOI: 10.1302/2058-5241.4.190022.