Complication Profile of a Computed Tomography-Guided Robotic-Arm Assisted Unicompartmental Knee Arthroplasty System: A Systematic Review and Meta-Analysis.

BACKGROUND

Robotic-arm-assisted unicompartmental knee arthroplasty (rUKA) has grown in popularity, but the spectrum of complications associated with any one platform remains incompletely characterized. This systematic review and meta-analysis evaluated the intraoperative, perioperative, and postoperative complication profile of a single computed tomography-guided, semi-active robotic platform and compared this against manual unicompartmental knee arthroplasty (mUKA) cohorts.

METHODS

PubMed, Embase, and Cochrane Library were searched for Level II to IV studies published since 2005 on complications associated with the rUKA system were reviewed. Risk of bias assessment was performed. The meta-analysis pooled comparative nonregistry studies as the primary analysis, evaluating complications of rUKA versus mUKA. A total of 35 articles, totaling 10,894 rUKA and 10,065 mUKA cases, were included. There were 21 intraoperative, nine postoperative medical, and 432 postoperative surgical complications reported for rUKA. The intraoperative complication incidence was 0.2%, including pin-related fractures, soft-tissue injuries, and mechanical system errors. Overall complications totaled 4.2% for rUKA and 5.5% for mUKA.

RESULTS

Meta-analysis of comparative studies demonstrated fewer overall complications occurring in rUKA (3.8 versus 5.5%; odds ratio (OR) 0.67, 95% confidence interval (CI) 0.55 to 0.82; P < 0.01), but no statistically significant difference for deep periprosthetic joint infection (OR 0.41, 95% CI 0.06 to 2.62; P = 0.34), additional procedures (OR 0.71, 95% CI 0.26 to 1.92; P = 0.49), or prosthetic loosening (OR 1.29, 95% CI 0.23 to 7.23; P = 0.77). Sensitivity analyses demonstrated reduction in additional procedures favoring rUKA (OR 0.53, 95% CI 0.39 to 0.71; P < 0.01), though this was driven predominantly by one registry study.

CONCLUSIONS

The rUKA platform demonstrated a low cumulative complication incidence and comparable safety to mUKA across pooled outcomes. Although differences did not reach statistical significance in primary nonregistry analyses, trends favored rUKA. These findings help further characterize the safety profile of this robotic platform and support the need for platform-specific complication reporting and longer-term comparative data.