Robotic Assistance in Unicompartmental Knee Arthroplasty Results in Superior Early Functional Recovery and Is More Likely to Meet Patient Expectations

Clinical Outcome Scores Post Medial Unicompartmental Knee Arthroplasty: A Comparison of the MAKO Robotic Arm versus the Oxford Conventional Approach

Introduction

Unicompartmental knee arthroplasty (UKA) has significant advantages over total knee arthroplasty (TKA). However, due to its need for precise positioning and soft tissue balancing, UKA failures and revision rates may be higher than that of TKA. Robotic-assisted UKA offers more accurate implant positioning, soft tissue balancing, improved lower limb alignment, and a reduction in surgical error. There are few studies studying functional outcomes post robotic-assisted UKA. The aim of this study was to compare the functional outcomes between robotic-assisted and conventional medial UKA.

Material and Methods

A retrospective review was done of 159 patients; 110 patients underwent conventional UKA while 49 patients underwent robotic-assisted UKA. Outcome measures included the Oxford Knee Score (OKS), Knee Society Score (KSS), Visual Analogue Score (VAS) for pain, and range of motion (ROM) at three months, one-year and two years post-UKA.

Results

Pre-operative patient demographics and outcome scores were not significantly different between both groups. ROM was significantly greater in the MAKO compared to the Oxford group at 3 months (p=0.039), 1 year (0.053) and 2 years (0.001) post-operation. While OKS, KSS and VAS scores improved for both groups, there were no significant differences in the final outcome measures. None of the patients experienced a mechanical failure, infection, or revision post-surgery. One patient each in the Oxford and MAKO group suffered a periprosthetic fracture.

Conclusion

Both robotic-assisted MAKO UKA and conventional Oxford UKA showed good clinical outcomes. Robotic-assisted MAKO UKA had superior ROM outcomes compared to conventional Oxford UKA up to two years post-surgery.

Comparison of Time and Rate of Achieving Minimal Clinically Important Difference: Robotic Versus Manual Unicompartmental Knee Arthroplasty

BACKGROUND

Robotics in unicompartmental knee arthroplasty (UKA) continues to increase with the ever-growing demand to use technology in the surgical setting. However, no studies have used minimal clinically important difference (MCID) to compare patient-reported outcome measures (PROMs) between robotic UKA (rUKA) and manual UKA (mUKA). This study aimed to compare the rate of achieving MCID for improvement (MCID-I) and worsening (MCID-W) and the time to achieving MCID.

METHODS

We conducted a retrospective analysis of robotic and manual UKAs performed between 2016 and 2022. Preoperative and postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) Global Physical, PROMIS Physical Function Short-Form 10a (PF-10a), and Knee Injury and Osteoarthritis Outcome Score-Physical Function Short-Form (KOOS-PS) scores were collected. Patients were stratified on reaching MCID-I, MCID-W, or "no notable change" (score between MCID-W and MCID-I). Survival curves with and without interval censoring were used to assess the time to achieving the MCID. Log-rank and weighted log-rank tests were used to compare groups.

RESULTS

A total of 256 UKAs (64 robotic and 192 manual) were analyzed. No differences were observed in the proportion of patients achieving MCID-I or MCID-W across all three PROMs. Similarly, median time to achieving MCID showed no significant differences between rUKA and mUKA for PROMIS Global Physical (3.3 versus 4.9 months, P = 0.44), PROMIS PF-10a (7.7 versus 8.3 months, P = 0.93), and KOOS-PS (3.0 versus 6.0 months, P = 0.055) scores, both with and without interval censoring.

DISCUSSION

This study indicates that rUKA and mUKA exhibit comparable rates of achieving MCID-I and MCID-W, along with similar median time to reach MCID. These findings offer valuable patient-centric insights into the effectiveness of rUKA. Additional studies evaluating the long-term outcomes of rUKA are needed to determine its long-term advantages.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

High Early Failure Rate of a Novel Cementless Unicompartmental Knee Arthroplasty

BACKGROUND

Unicompartmental knee arthroplasty (UKA) is an accepted treatment for antero-medial osteoarthritis with low overall failure rates. In the United States, cementation remains the gold standard of implant fixation; however, multiple studies have shown potential benefits of increased survivorship with cementless fixation. The aim of this study was to evaluate clinical and radiographic outcomes of a novel cementless medial UKA implant. We hypothesized the cementless UKA would perform as well as or better than the cemented UKA.

METHODS

Clinical outcomes, including patient-reported outcome measures, were prospectively collected for 111 patients (127 knees) implanted with a novel cementless UKA from February 2021 to December 2022. Radiographic lucency zones surrounding the femoral and tibial components were evaluated from postoperative radiographs. Data was collected preoperatively and at standard postoperative intervals until final follow-up or implant revision. Revisions were necessary in 15 of 127 UKAs (11.8%) at a mean of 0.9 years (range, zero to two).

RESULTS

The most common revision reason was aseptic loosening (12). Kaplan-Meier survival was 84.0% (95% CI [confidence interval] ±3.98%) at 2.4 years. The Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) 12-month scores differed significantly between revision and non-revision groups (61.9, 95% CI ±13.4 versus 75.1, 95% CI ±16.9; P = 0.01). In patients revised for aseptic loosening, 11 of 12 tibial implants had progressive radiolucent lines on pre-revision imaging. Revision operative records noted minimal to no bone ingrowth on the tibial implant undersurface.

CONCLUSIONS

This novel cementless medial UKA implant demonstrated a high rate of early revision, mostly for tibial-sided complications. Compared to non-revised implants, revised implants had higher rates of tibial and femoral radiolucencies on postoperative radiographs as well as lower KOOS JR 12-month scores pre-revision. When recorded in the operative record, no significant bone ingrowth was seen on the porous implant surfaces.

A case-matched series comparing functional outcomes for robotic-assisted unicompartmental knee arthroplasty versus functionally aligned robotic-assisted total knee arthroplasty

Aims

Unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) have both been shown to be effective treatments for osteoarthritis (OA) of the knee. Many studies have compared the outcomes of the two treatments, but less so with the use of robotics, or individualized TKA alignment techniques. Functional alignment (FA) is a novel technique for performing a TKA and shares many principles with UKA. Our aim was to compare outcomes from a case-matched series of robotic-assisted UKAs and robotic-assisted TKAs performed using FA.

Methods

From a prospectively collected database between April 2015 and December 2019, patients who underwent a robotic-assisted medial UKA (RA-UKA) were case-matched with patients who had undergone a FA robotic-assisted TKA (RA-TKA) during the same time period. Patients were matched for preoperative BMI, sex, age, and Forgotten Joint Score (FJS). A total of 101 matched pairs were eligible for final review. Postoperatively the groups were then compared for differences in patient-reported outcome measures (PROMs), range of motion (ROM), ability to ascend and descend stairs, and ability to kneel.

Results

Both groups had significant improvements in mean FJS (65.1 points in the TKA group and 65.3 points in the UKA group) and mean Oxford Knee Score (OKS) (20 points in the TKA group and 18.2 in the UKA group) two years following surgery. The UKA group had superior outcomes at three months in the OKS and at one year in ROM (5°), ability to kneel (0.5 points on OKS question), and ascend (1.3 points on OKS question) and descend stairs (0.8 points on OKS question), but these were not greater than the minimal clinically important difference. There were no differences seen in FJS or OKS at one year postoperatively. There were no statistically significant differences between the groups at 24 months in all the variables assessed.

Conclusion

FA-RATKA and RA-UKA are both successful treatments for medial compartmental knee arthritis in this study. The UKA group showed a quicker recovery, but this study demonstrated equivalent two-year outcomes in all outcomes measured including stair ascent and descent, and kneeling.

Robotic-Assisted Medial Unicompartmental Knee Arthroplasty Provides Better FJS-12 Score and Lower Mid-Term Complication Rates Compared to Conventional Implantation: A Systematic Review and Meta-Analysis

Background: Robotic-assisted unicompartmental arthroplasty (rUKA) is gradually gaining more popularity than its conventional counterpart (cUKA). Current studies are highly heterogenic in terms of methodology and the reported results; therefore, establishing the optimal recommendation for patients becomes less straightforward. For this reason, this meta-analysis aims to provide an up-to-date evidence-based analysis on current evidence regarding clinical outcomes and complication rates following rUKA and cUKA. Methods: A meta-analysis was conducted following PRISMA guidelines. Five databases were searched, PubMed via MEDLINE, Epistemonikos, Cochrane Library, Web of Science, and Scopus. The relevant inclusion criteria were as follows: comparative clinical studies in which medial rUKA was compared to medial cUKA (prospective or retrospective designs), (2) human studies, (3) meta-analyses for cross-referencing, and (4) English language. The relevant extracted data were patient demographics, patient-reported outcome measures (PROMs), range of motion, and complications. A random-effects meta-analysis and subgroup analysis were conducted. The results include mean differences (MDs) and odds ratios (ORs), along with 95% confidence intervals (CIs) for continuous and binary variables, respectively. Results: rUKA showed a higher overall FJS-12 score compared to cUKA, with MD = 6.02 (95%CI: -0.07 to 12.1), p = 0.05. At 6 months postoperatively, the MD increased to 10.31 (95%CI: 5.14 to 15.49), p < 0.01. At a minimum 36-month follow-up, cUKA had a higher all-cause revision rate, with OR = 3.31 (95%CI: 1.25 to 8.8), p = 0.02, and at a minimum 60-month follow-up, a higher aseptic loosening rate, with OR = 3.86 (95%CI: 1.51 to 9.91), p < 0.01, compared to rUKA. Conclusions: rUKA provides better FJS-12 results compared to cUKA, as well as lower all-cause revision and aseptic loosening rates at 36- and 60-month follow-up, respectively. However, long-term follow-up is still pending.

Patient satisfaction following unicompartmental knee arthroplasty: Current concepts

Unicompartmental knee arthroplasty (UKA) has gained progressive popularity in recent decades, currently comprising approximately 10% of knee arthroplasties in the United States. Nonetheless, UKA has not yet solidified its position as the superior treatment for isolated compartment osteoarthritis, as initially reported implant survivorship was subpar, leading to hesitation in its utilization and stricter patient indications compared to total knee arthroplasty. Patient satisfaction following knee arthroplasty has emerged as a critical metric to gauge patient acceptance and contentment with surgical interventions. Currently, a variety of UKA types exist, differing in bearing design, fixation techniques such as cementless or cemented fixation, and robotic-assisted systems, each with its own merits and drawbacks. Multiple studies have demonstrated the contributions of these innovations to improve clinical outcomes and implant survivorship. However, the abundance of studies has made it challenging to establish a clear overview. This paper provides an overview of the current concepts of UKA, evaluating various aspects of UKA referencing to patient satisfaction and providing a recap of its historical development. Available research demonstrated no significantly universal superior variant of UKA.

Long-term functional success and robust implant survival in lateral unicompartmental knee arthroplasty: A case series with a mean follow-up of twenty two and a half years

PURPOSE

Lateral unicompartmental knee arthroplasty (UKA) is an accepted treatment option in cases of end-stage lateral osteoarthritis. While lateral UKA has many proposed advantages compared to total knee arthroplasty, its technical challenges and relatively small number of cases make this an uncommon procedure. The aim of this study was to report the survivorship and functional outcomes beyond 20 years of follow-up of isolated UKA.

METHODS

Between January 1988 and October 2003, 54 lateral UKAs were performed in a single center. The fitted prosthesis was a fixed plate and cemented polyethylene (PE). All patients had isolated lateral tibiofemoral osteoarthritis, including five open meniscectomies, three arthroscopies, and three open reductions of lateral tibial plateau fractures. Patients with a minimum of 20 years of follow-up were included in the final analysis.

RESULTS

Of the 54 UKA, 22 died before reaching the minimum follow-up period and four were lost to follow-up. Twenty-eight were included in the final analysis. Among them, 21 patients remained alive and an additional seven were deceased after 20 years. The mean age at the last follow-up was 84.8 ± 11.9 years with a mean follow-up duration of 22.5 ± 2.1 years. Of the 28 knees, eight underwent revision surgery (5 for the progression of osteoarthritis; 2 for aseptic loosening; 1 for PE wear). Kaplan-Meier survival analysis revealed a survival rate at 20 and 25 years of 72.3% (CI 59.1; 88.6). The average time to revision was 14.9 ± 4.9 years. At the last follow-up, the mean function Knee Society Score (KSS) was 41.5 ± 32.9 and the mean objective KSS score was 79.4 ± 9.7. In the unrevised population, 94.7% of patients (n = 18) reported being satisfied or very satisfied with the surgery.

CONCLUSION

Lateral UKA remains a viable treatment option for patients with isolated lateral tibiofemoral osteoarthritis, providing satisfactory 20-year implant survivorship and high patient satisfaction.

Robotic-assisted unicompartmental knee arthroplasty improves functional outcomes, complications, and revisions

Aims

Robotic-assisted unicompartmental knee arthroplasty (R-UKA) has been proposed as an approach to improve the results of the conventional manual UKA (C-UKA). The aim of this meta-analysis was to analyze the studies comparing R-UKA and C-UKA in terms of clinical outcomes, radiological results, operating time, complications, and revisions.

Methods

The literature search was conducted on three databases (PubMed, Cochrane, and Web of Science) on 20 February 2024 according to the guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Inclusion criteria were comparative studies, written in the English language, with no time limitations, on the comparison of R-UKA and C-UKA. The quality of each article was assessed using the Downs and Black Checklist for Measuring Quality.

Results

Among the 3,669 articles retrieved, 21 studies on 19 series of patients were included. A total of 3,074 patients (59.5% female and 40.5% male; mean age 65.2 years (SD 3.9); mean BMI 27.4 kg/m2 (SD 2.2)) were analyzed. R-UKA obtained a superior Knee Society Score improvement compared to C-UKA (mean difference (MD) 4.9; p < 0.001) and better Forgotten Joint Score postoperative values (MD 5.5; p = 0.032). The analysis of radiological outcomes did not find a statistically significant difference between the two approaches. R-UKA showed longer operating time (MD 15.6; p < 0.001), but reduced complication and revision rates compared to C-UKA (5.2% vs 10.1% and 4.1% vs 7.2%, respectively).

Conclusion

This meta-analysis showed that the robotic approach for UKA provided a significant improvement in functional outcomes compared to the conventional manual technique. R-UKA showed similar radiological results and longer operating time, but reduced complication and revision rates compared to C-UKA. Overall, R-UKA seems to provide relevant benefits over C-UKA in the management of patients undergoing UKA.

Factors predicting lower limb alignment after Oxford medial unicompartmental knee arthroplasty

This study aimed to identify the factors affecting hip-knee-ankle (HKA) angle following Oxford medial unicompartmental knee arthroplasty (MUKA). A retrospective analysis of 200 patients who underwent Oxford MUKA from June 2018 to October 2020 was conducted. Univariate and multivariate analyses were performed to investigate the impact of surgical and radiographic characteristics on the postoperative HKA angle. The mean HKA angle was 9.5 ± 4.3° before surgery and 3.6 ± 3.7° after surgery (p < 0.001). The postoperative HKA angle significantly correlated with the preoperative HKA angle, bearing size, tibial component alignment angle, and BMI (r = 0.71, p < 0.001; r =  - 0.24, p = 0.001; r = 0.21, p = 0.004; r =  - 0.18, p = 0.011). Multiple linear regression analysis revealed that the preoperative HKA angle (β = 0.68, p < 0.001), bearing size (β =  - 0.31, p < 0.001), tibial component alignment angle (β = 0.14, p = 0.003), and BMI (β =  - 0.09, p = 0.047) significantly affected the postoperative HKA angle. In conclusion, larger preoperative varus deformity, smaller bearing size, greater varus alignment of the tibial component, and lower BMI lead to greater postoperative varus alignment of the lower limb in Oxford MUKA. With this concept, surgeons can more accurately predict postoperative lower limb alignment and avoid malalignment in Oxford MUKA.

Patient satisfaction following robotic unicompartmental knee arthroplasty: A systematic review and meta-analysis

BACKGROUND

Unicompartmental knee arthroplasty (UKA) is a viable alternative to total knee arthroplasty (TKA) for osteoarthritis patients with single-compartment involvement, with advantages including accelerated recovery, reduced pain, and improved function. Robotic-assisted UKA (rUKA) is a promising development that ensures precise implant positioning and limb alignment. However, concerns about complications remain.

OBJECTIVE

This study looks at patient satisfaction as a key metric for determining the efficacy of rUKA versus manual UKA (mUKA).

METHODS

The search strategy for this study followed PRISMA. Using precise keywords, PubMed, Scopus, Web of Science, and the Cochrane library were searched. English articles were searched until August 2, 2023. Selection criteria included mUKA and rUKA patient satisfaction studies. The NOS scale evaluated study quality. Meta-analysis was done with R and heterogeneity analysis.

RESULTS

This systematic review examined 5 studies with 1060 UKAs (532 robotic-assisted and 528 manual). Variable satisfaction assessment methods were used. Three studies found no difference in patient satisfaction after robotic-assisted UKA, but two found a higher satisfaction. Meta-analysis showed robotic-assisted UKA improved patient satisfaction (OR = 1.72 [1.25-2.37]). Overall, most studies showed low risk of bias, except one with higher bias.

CONCLUSION

This review suggests that robotic assistance may enhance patient satisfaction in UKA procedures.

American Academy of Orthopaedic Surgeons Clinical Practice Guideline Summary of Surgical Management of Osteoarthritis of the Knee

The Surgical Management of Osteoarthritis of the Knee Evidence-Based Clinical Practice Guideline is based on a systematic review of published studies for surgical management of osteoarthritis of the knee in skeletally mature patients. This guideline contains 16 recommendations and seven options to assist orthopaedic surgeons and all qualified physicians with the surgical management of patients with osteoarthritis of the knee based on the best current available evidence. It is also intended to serve as an information resource for professional healthcare practitioners and developers of practice guidelines and recommendations. In addition to providing pragmatic practice recommendations, this guideline also highlights gaps in the literature and informs areas for future research and quality measure development.

Robotic Versus Conventional Unicompartmental Knee Surgery: A Comprehensive Systematic Review and Meta-Analysis

Robotic-assisted surgery is a computer-controlled technique that may improve the accuracy and outcomes of unicompartmental total knee arthroplasty (TKA), a partial knee replacement surgery. The purpose of a meta-analysis about robotic-assisted versus conventional surgery for unicompartmental TKA is to compare the effectiveness of these two methods based on the current evidence. Our meta-analysis can help inform clinical decisions and guidelines for surgeons and patients who are considering unicompartmental TKA as a treatment option. We searched four online databases for studies that compared the two methods until March 2023. We used RevMan software to combine the data from the studies. We calculated the mean difference (MD) and the 95% confidence interval (CI) for each outcome, which are statistical measures of the difference and the uncertainty between the two methods. We included 16 studies in our analysis. We found that robotic-assisted surgery had a better hip-knee-ankle angle, which is a measure of how well the knee is aligned, than conventional surgery (MD = 0.86, 95% CI = 0.16-1.56). We also found that robotic-assisted surgery had a better Oxford Knee score, which is a measure of how well the knee functions, than conventional surgery (MD = 3.03, 95% CI = 0.96-5.110). This study compared the results of conventional and robotic-assisted unicompartmental knee arthroplasty in 12 studies. We concluded that robotic-assisted surgery may have some benefits over conventional surgery in terms of alignment and function of the knee. However, we did not find any significant difference between the two methods in terms of other outcomes, such as pain, range of motion, health status, and joint awareness. Therefore, we suggest that more research is needed to confirm these results and evaluate the long-term effects and cost-effectiveness of robotic-assisted surgery.

Long-term study of functional outcomes of robotic assisted medial UKA using mid-vastus approach in a high-volume centre

Robotic UKA is one of the recent advancement in surgical management for medial compartment knee osteoarthritis. Over the years, there have been many studies which have showed results of various conventional UKA, high tibial osteotomy and even robotic uka for medial OA of knee all over the world. But still there is very less work on long-term outcome-based analysis of functional outcomes of robotic assisted medial UKA using mid-vastus approach, which was the aim of the study. A total of 680 patients with medial OA knee that were undergone robotic assisted UKA. The study was done at tertiary teaching institute and hospital from November 2016 to October 2022. The assessment of pain, clinical-functional assessment, walking ability, range of motion were assessed by KSS, SF-12 at pre-operatively, mid-term follow-ups and at final follow-up -5.03(± 0.52) years after surgery. 680 patients suited for medial UKA in our study with mean age of 65 ± 10.6 years. Average operating time was 42 ± 4.7 min. The mean postoperative KSS was 93 ± 4.3, the mean SF-12 was 49 ± 9.1, 55 ± 8.7 for PS and MS, respectively. The patient had better KSS and SF-12 when compared pre-operatively and final follow-up (p -0.012 and -9.320, p -0.017 and -7.475, p -0.014 and -5.196, p -0.021 and -7.418, respectively). Complications were also very less. Robotic UKA using mid-vastus approach is effective treatment for medial compartmental OA knee. On short/long-term follow-up of patients, functional and radiological outcomes were good with few complications rates.

Robotic-Assisted Total Knee Arthroplasty is Safe in the Ambulatory Surgery Center Setting

BACKGROUND

Robotic-assisted total knee arthroplasty (RA-TKA) has become more popular in the United States. With the significant trend towards performing TKA in outpatient and ambulatory surgery center (ASC) settings, this study was implemented to determine the safety and efficacy of RA-TKA in an ASC.

METHOD

A retrospective review identified 172 outpatient TKAs (86 RA-TKAs and 86 TKAs) performed between January 2020 and January 2021. All surgeries were performed by the same surgeon at the same free-standing ASC. Patients were followed for at least 90 days after surgery; complications, reoperations, readmissions, operative time, and patient-reported outcomes were recorded.

RESULTS

In both groups, all patients were successfully discharged home from the ASC on the day of surgery. No differences were noted in overall complications, reoperations, hospital admissions, or delays in discharge. RA-TKA had slightly longer operative times (79 vs 75 min [p = 0.017]) and total length of stay at the ASC (468 vs 412 min [p < 0.0001]) than conventional TKA. No significant differences were noted in outcome scores at 2-, 6-, or 12-week follow-ups.

CONCLUSIONS

Our results showed that RA-TKA can be successfully implemented in an ASC, with similar outcomes compared with TKA using conventional instrumentation. Initial surgical times were increased secondary to the learning curve of implementing RA-TKA. Long-term follow-up is necessary to determine implant longevity and long-term outcomes.

METHOD

A retrospective review identified 172 outpatient TKAs (86 RA-TKAs and 86 TKAs) performed between January 2020 and January 2021. All surgeries were performed by the same surgeon at the same free-standing ASC. Patients were followed for at least 90 days after surgery; complications, reoperations, readmissions, operative time, and patient-reported outcomes were recorded.

RESULTS

In both groups, all patients were successfully discharged home from the ASC on the day of surgery. No differences were noted in overall complications, reoperations, hospital admissions, or delays in discharge. RA-TKA had slightly longer operative times (79 vs 75 min [p = 0.017]) and total length of stay at the ASC (468 vs 412 min [p < 0.0001]) than conventional TKA. No significant differences were noted in outcome scores at 2-, 6-, or 12-week follow-ups.

CONCLUSIONS

Our results showed that RA-TKA can be successfully implemented in an ASC, with similar outcomes compared with TKA using conventional instrumentation. Initial surgical times were increased secondary to the learning curve of implementing RA-TKA. Long-term follow-up is necessary to determine implant longevity and long-term outcomes.

Robotic-Assisted Versus Manual Unicompartmental Knee Arthroplasty: A Time-Driven Activity-Based Cost Analysis

BACKGROUND

The cost-effectiveness of robotic-assisted unicompartmental knee arthroplasty (RA-UKA) remains unclear. Time-driven activity-based costing (TDABC) has been shown to accurately reflect true resource utilization. This study aimed to compare true facility costs between RA-UKA and conventional UKA.

METHODS

We identified 265 consecutive UKAs (133 RA, 132 conventional) performed at a specialty hospital in 2016-2020. Itemized facility costs were calculated using TDABC. Separate analyses including and excluding implant costs were performed. Multiple regression was performed to determine the independent effect of robotic assistance on facility costs.

RESULTS

Due to longer operative time, RA-UKA patients had higher personnel costs and total facility costs ($2,270 vs $1,854, P < .001). Controlling for demographics and comorbidities, robotic assistance was associated with an increase in personnel costs of $399.25 (95% confidence interval [CI] $343.75-$454.74, P < .001), reduction in supply costs of $55.03 (95% CI $0.56-$109.50, P = .048), and increase in total facility costs of $344.27 (95% CI $265.24-$423.31, P < .001) per case. However, after factoring in implant costs, robotic assistance was associated with a reduction in total facility costs of $235.87 (95% CI $40.88-$430.85, P < .001) per case.

CONCLUSION

Using TDABC, overall facility costs were lower in RA-UKA despite a longer operative time. To facilitate wider adoption of this technology, implant manufacturers may negotiate lower implant costs based on volume commitments when robotic assistance is used. These supply cost savings appear to offset a portion of the increased costs. Nonetheless, further research is needed to determine if RA-UKA can improve clinical outcomes and create value in arthroplasty.