Robotic Assistance is Associated With No Intraoperative Fluoroscopy or Radiation Exposure During Direct Anterior Total Hip Arthroplasty

Abstract

Background

As more total hip arthroplasty (THA) procedures continue to be performed and concomitant intraoperative fluoroscopic utilization continues to increase, it is important for surgeons to critically analyze this practice during their procedures. The direct anterior approach (DAA) is a popular technique, but often requires the use of fluoroscopy for evaluation of component positioning and implantation. Computed tomography (CT)–based robotic-assisted THA (RA-THA) may represent an alternative to conventional procedures, which may allow the avoidance of the use of intraoperative fluoroscopy to be avoided and instead rely on a preoperative CT scan of the patient and intraoperative mapping. The purpose of this study was to evaluate the difference in radiation exposure from CT-based RA-THA DAA vs fluoroscopy-guided conventional THA DAA based on values from a cadaver study.

Methods

There were 2 surgeons who had previous extensive experience with the DAA, as well as conventional and RA-THA. They completed bilateral direct anterior THAs on 6 cadaver specimens. For each cadaver, a conventional THA with fluoroscopy was performed on the first hip, and a robotically assisted THA without fluoroscopy was performed on the contralateral hip. For all robotic-assisted cases, a preoperative 3-dimensional CT was performed. The radiation dosage from the preoperative scan was acquired through the radiation dose structured reports. Radiation exposure dosage for intraoperative fluoroscopy required tabulation of the number of fluoroscopy shots performed for each case as well as the length of time of exposure. This time was then converted to an effective radiation dose based on accepted standards, and this was multiplied by the average number of fluoroscopy shots per case to determine the average dosage per case.

Results

No fluoroscopic images were taken during the RA-THA using the DAA. There was a mean of 21 ± 8.9 fluoroscopic shots taken during each fluoroscopy-guided conventional THA using the DAA. The minimum number of fluoroscopic shots was 9, with a maximum of 31. Total radiation exposure ranged from 300 to 1033 mrem, with an average of 700 mrem. The average radiation exposure for a hip CT scan was 289 mrem.

Conclusions

In this cadaver-based study, the use of a CT-based RA-THA DAA eliminated the need for intraoperative fluoroscopy, removing the concern of radiation exposure to the surgeon and surgical staff. The CT-based RA-THA DAA does require a preoperative CT scan of the patient; however, the radiation dosage to the patient was equivalent to 8.7 intraoperative fluoroscopy shots. As more surgeons, patients, and surgical staff are exposed to an increasing number of orthopaedic procedures that require ionizing radiation to generate images, such as fluoroscopy and CT, it is important to consider the radiation dosage for all individuals and understand the positives and negatives of each treatment. We must consider the overall long-term health impacts of continuous fluoroscopy vs a one-time CT scan. This is of particular importance to the surgeon and surgical staff who may be exposed to cumulative doses during multiple procedures.