1-year outcomes of robotic-assisted, computer-assisted, and manual total hip arthroplasty after the learning curve

Introduction: While comparisons exist between manual (MA-THA), computer-assisted (CA-THA), and robotic-assisted total hip arthroplasty (RA-THA), they have not considered surgeon/hospital learning curves. Therefore, we compared surgical outcomes between MA-THA/CA-THA/RA-THA among hospitals with >= 1 year of RA-THA experience. Methods: In this retrospective study (2016-2023, Premier Healthcare Database), we included adults undergoing elective MA-THA/CA-THA/RA-THA for non-traumatic/non-neoplastic diagnoses. Our primary outcome was any mechanical complication within 1-year follow-up; secondary outcomes included any infection within 1 year. We conducted pairwise mixed-effects logistic regression and reported odds ratios (OR) and 95% confidence intervals (CI). Results: Among 75,966 MA-THAs, 6,207 CA-THAs and 17,497 RA-THAs, odds of any mechanical complication within 1-year were: CA-THA versus MA-THA (OR 0.63, CI 0.52-0.75; p < 0.001), RA-THA versus MA-THA (OR 0.81, CI 0.73-0.90; p < 0.001) and RA-THA versus CA-THA (OR 1.44, CI 1.14-1.82; p = 0.003). Differences between RA-THA and CA-THA were primarily due to higher odds of mechanical loosening (OR 2.40, CI 1.19-4.85; p= 0.015) with RA-THA. Dislocation was less likely with RA-THA compared to MA-THA (OR 0.57, CI 0.44-0.72; p < 0.001). CA-THA (OR 0.46 CI 0.34-0.63; p < 0.001) and RA-THA (OR 0.83 CI 0.71-0.97; p = 0.022) were associated with significantly lower odds of infection within 1 year compared to MA-THA. RA-THA was associated with higher odds of infection within 1 year compared to CA-THA (OR 2.11 CI 1.43-3.09; p < 0.001). Conclusions: With up to 1-year follow-up, CA-THA was associated with the lowest odds for mechanical complications, primarily due to mechanical loosening and infection.