Cost-analysis of total knee arthroplasty with robot-assisted surgery versus conventional approach.

Total knee arthroplasty (TKA) volume is rising, and robotic assistance is promoted for greater precision and faster recovery; however, cost data from Romania remain limited. This retrospective cohort study analysis examined 400 consecutive primary TKAs: 100 robotic-assisted (rTKA) and 300 manual (mTKA). Outcomes included operating room (OR) time, length of stay (LOS), 90-day events, and total in-hospital costs broken down by category. Cost determinants were explored using LASSO with cross-validation and corroborated by ordinary least squares models. rTKA was associated with longer OR time (103.55 ± 23.92 vs. 80.29 ± 17.53 min) and longer LOS (5.99 ± 1.46 vs. 4.79 ± 1.35 days). The subvastus approach correlated with shorter LOS. Hospitalization costs reflected the interplay of perioperative care and institutional practice rather than the surgical approach alone: higher expenditures tracked most strongly with ward medications and sanitary materials, robotic use itself, longer OR time, and ICU consumables, whereas the subvastus approach tended to lower costs. Model fit was moderate. Within 90 days, rTKA had one non-injurious fall unrelated to implant stability; mTKA had two wound dehiscences (one readmission) and one transient stiffness that resolved with rehabilitation. In this setting, rTKA was associated with higher hospitalization costs despite low early complication rates in both groups. Improving specific steps before, during, and after surgery could reduce the extra costs of robotic TKA without harming results. To know the true value, larger multi-hospital studies with longer follow-up, detailed cost breakdowns, and patient-reported outcomes are needed.