Robotic-assisted versus conventional total knee arthroplasty: a systematic review and meta-analysis of randomized controlled trials

Abstract

Objectives: Robotic knee arthroplasty procedures have emerged as a new trend, garnering attention from orthopedic surgeons globally. It has been hypothesized that the use of robotics enhances the accuracy of prosthesis positioning and alignment restoration. The objective of this study was to provide a high-level, evidence-based comparison between robotic total knee replacements and conventional methods, focusing on radiological and functional outcomes.

Methods: We searched five databases from their inception until June 1, 2022, specifically targeting randomized controlled trials (RCTs) that compared the outcomes of robotic and conventional total knee replacements. We were interested in outcomes such as knee range of motion, clinical and function knee society scores, the Western Ontario and McMaster University score (WOMAC), the Hospital of Special Surgery score, complications, and radiological alignment. This review was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes guidelines. We assessed the risk of bias using the revised Cochrane risk-of-bias tool for randomized trials (RoB 2).

Results: Our search returned seven RCTs suitable for our analysis, which included a total of 1942 knees; 974 of these knees were implanted using robotic arms while the remaining 968 utilized jig-based knee systems. Our findings indicated that robotic knees had significantly better post-operative anatomical (OR - 0.82; 95% CI, - 1.027 to - 0.58, p value < 0.00001) and mechanical restoration (OR - 0.95; 95% CI, - 1.49 to - 0.41, p value < 0.0006). While knee range of motion (OR - 2.23; 95% CI - 4.89-0.43, p value 0.1) and femoral prosthesis position (OR - 0.98; 95% CI, - 2.03-0.08, p value 0.07) also favored robotic knees, these differences did not reach statistical significance. Both clinical and functional outcomes, as well as the rate of complications, were found to be statistically similar between the groups undergoing robotic and traditional knee replacement surgeries.

Conclusion: This meta-analysis indicates that robotic total knee replacements offer superior post-operative anatomical and mechanical alignment compared to conventional total knee replacements. Despite this, clinical and functional outcomes, as well as complication rates, were similar between the two. These findings should be considered in light of potential confounding factors. More randomized controlled trials with the latest robotic systems are needed to confirm any superior functional and clinical outcomes from robotic-assisted surgeries.

Level of evidence: I.

Keywords: Conventional knee arthroplasty; Jig-based arthroplasty; Robotic arthroplasty; Total knee arthroplasty.

Fig. 1

Search strategy flowchart

Fig. 2

Forest plot of clinical knee society score at the final follow up between RTKA and CTKA, CI confidence interval

Fig. 3

Forest plot of functional knee society score at the final follow up between RTKA and CTKA, CI confidence interval

Fig. 4

Forest plot of hospital of special surgery score at the final follow up between RTKA and CTKA, CI confidence interval

Fig. 5

Forest plot of WOMAC score at the final follow up between RTKA and CTKA, CI confidence interval

Fig. 6

Forest plot of range of motion score at the final follow up between RTKA and CTKA, CI confidence interval

Fig. 7

Forest plot of complications at the final follow up between RTKA and CTKA, CI confidence interval

Fig. 8

Forest plot of tibiofemoral axis at final follow up between RTKA and CTKA, CI confidence interval

Fig. 9

Forest plot of mechanical axis at final follow up between RTKA and CTKA, CI confidence interval

Fig. 10

Forest plot of femoral flexion angle at final follow up between RTKA and CTKA, CI confidence interval

Fig. 11

Forest plot of anteroposterior tibial angle at final follow up between RTKA and CTKA, CI confidence interval

Fig. 12

Forest plot of lateral tibial angle at final follow up between RTKA and CTKA, CI confidence interval