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.