Implant-Related Complications After Robotic-Assisted Versus Manual Revision Knee Arthroplasty: A Propensity-Matched Cohort Study.

INTRODUCTION As robotic-assisted total knee arthroplasty (TKA) gains traction in revision procedures, the urgent need to investigate its effectiveness compared with manual methods becomes apparent.

Methods

Data were retrospectively obtained from the TriNetX Collaborative Network. Revision TKA (rKA) cases were identified using CPT codes and categorized as manual or robotic assisted using ICD-10 procedure codes. Cohorts were balanced with 1:1 propensity score matching for demographics, comorbidities, and revision history. Complication rates were compared across follow-up using chi-square analysis.

Results

An initial query identified 19,088 manual and 2,709 robotic-assisted rKA cases. After 1:1 propensity matching, 2,010 patients remained in each group. Robotic rKA had significantly lower mechanical implant‑related complications at 3 and 6 months (OR 1.67 and 1.66; P < 0.001) and lower early VTE, while PJI, readmission, and revision rates were not significantly different. Manual rKA showed higher opioid use at 0 to 3 months (OR 1.40, 95% CI, 1.14 to 1.71, P < 0.001) and 3 to 6 months (OR 1.28, 95% CI, 1.12 to 1.47, P < 0.001) and throughout the 3 years of follow-up.Throughout the follow-up period, patellar dislocation, wound infection, non‑implant-related complications, and transfusion did not differ. At 1 year, manual rKA had higher instability (OR 1.59; P = 0.001) and higher hazard of mechanical implant‑related complications (HR 1.52, 95% CI, 1.32 to 1.75; P = 0.049). Instability, loosening, and periprosthetic fracture remained higher at 2 to 3 years, and revision was significantly more frequent at 3 years (13.5% vs. 11.4%; OR 1.22, 95% CI, 1.02 to 1.46; P = 0.03).

Discussion

Robotic-assisted rKA was associated with markedly lower mechanical implant‑related complications across early and midterm follow-up, including reduced rates of instability, aseptic loosening, periprosthetic fracture, VTE, and lower opioid requirements. Rates of PJI, readmission, and revision were largely comparable, although manual rKA demonstrated a markedly higher revision rate by 3 years. These findings suggest that robotic assistance may improve implant reliability and postoperative recovery, but prospective studies and cost-effectiveness analyses remain necessary.