Robotic-Assisted Direct Anterior Approach Total Hip Arthroplasty: A 6.5-Fold Reduction in Fluoroscopic Radiation Exposure.

Introduction: Direct anterior approach (DAA) for total hip arthroplasty (THA) is increasing in popularity. Fluoroscopy is commonly utilized during DAA THA to increase the accuracy of component placement. The objective of this study was to compare the mean fluoroscopy time and radiation dose for DAA THA when utilizing robotic-assistance (RA), computer-assisted navigation (CAN), or manual (M) technique.

Methods: A retrospective review identified 6,541 patients who underwent primary, unilateral DAA THA between 2016 and 2023, including 4,333 M-THA, 1,158 RA-THA, and 1,050 CAN-THA. The mean age was 65 years (range, 20 to 96), the mean body mass index was 26 (range, 15 to 56), and 63% were women. The mean fluoroscopy time (seconds) and radiation dose in milliGray (mGy) were compared between cohorts. Regression analysis controlled for differences in baseline demographics.

Results: The RA-THA cohort had a shorter mean fluoroscopy time (4.4 ± 5.6 seconds) than both the CAN-THA (17.6 ± 9.1 seconds, P < 0.001) and M-THA (21.8 ± 39.4 seconds, P < 0.001) cohorts. The CAN-THA cohort also had a shorter mean fluoroscopy time than M-THA cases (P < 0.001). The RA-THA cohort had a smaller mean fluoroscopic radiation dose (0.4 ± 0.6 mGy) than both CAN-THA (2.6 ± 2.2 mGy, P < 0.001) and M-THA (2.5 ± 2.5 mGy, P < 0.001). There was no difference in fluoroscopic radiation dose between the M-THA and CAN-THA cohorts (P = 0.822).

Conclusion: In this series of DAA THA, RA-THA required a 4.0 to 5.0-fold shorter mean fluoroscopy time and a 6.5-fold smaller mean fluoroscopic radiation dose compared to CAN-THA and M-THA. As DAA THA volume increases, surgeons should consider the cumulative radiation exposure to themselves, patients, and operating room staff.