Image-based navigation-assisted total hip arthroplasty in patients with morbid obesity: a matched cohort study in the...

Image-based navigation-assisted total hip arthroplasty (THA) has been increasingly adopted to improve component positioning and reduce complications; however, its clinical benefit in patients who have morbid obesity remains unclear. The purpose of this study was to compare (1) surgical complications, (2) thromboembolic events, and (3) reoperation and revision rates between image-based navigation-assisted and manual THA in a matched cohort of patients who have morbid obesity. Using an administrative claims database, we conducted a retrospective matched cohort study of patients who had morbid obesity (BMI ≥ 40) and underwent elective primary THA between 2010 and 2023. Image-based navigation-assisted cases were matched 1:3 to manual THA controls by age, sex, year of surgery, diabetes, hypertension, tobacco use, and alcohol use. After matching, 5,835 patients who had morbid obesity undergoing THA were analyzed (1,473 navigation-assisted; 4,362 manual) with comparable baseline demographics and comorbidities. Outcomes included surgical complications (prosthetic joint infection [PJI], surgical site infection, dislocation, periprosthetic fracture, mechanical loosening, limb length discrepancy [LLD]), thromboembolic events (pulmonary embolism, deep vein thrombosis [DVT]), same-day blood transfusions, and revision surgeries (septic and aseptic) assessed at multiple postoperative timepoints including 30-days, 90-days, one-year, and two-year timepoints. Across all timepoints, image-based navigation-assisted THA was not associated with reduced rates of surgical complications, thromboembolic events, or revisions compared with manual THA (P > 0.05), with the exception of same-day blood transfusions (0.8% versus 1.9%, P = 0.005). PJI, dislocation, mechanical complications, DVT, pulmonary embolism, and septic or aseptic revision rates were statistically similar between cohorts at all time points analyzed (P > 0.05). In a large national cohort of patients who had morbid obesity and underwent primary THA, image-based navigation-assistance did not generally confer measurable clinical advantages over manual techniques outside of same-day blood transfusions. Despite increasing utilization, these findings suggest that routine use of image-based navigation in this high-risk population may not provide added clinical value within two years postoperatively, raising important considerations regarding its cost-effectiveness and role in value-based care.