Robotic-assisted Navigation Requiring Perioperative CT in Posterior Spinal Fusion and Instrumentation for Idiopathic...

Robotic-assisted navigation (RAN) during posterior spinal fusion and instrumentation (PSFI) for pediatric patients with idiopathic scoliosis has been increasingly adopted over the traditional freehand (FH) technique due to enhanced accuracy. RAN requires either intraoperative or preoperative three-dimensional imaging or computed tomography (CT). Safety concerns, therefore, exist with regard to radiation exposure for the patient and surgeon, who have been shown to experience higher cancer rates than the general population. The objective of this study was to compare the mean intraoperative fluoroscopy radiation dosage and total perioperative radiation dosage between RAN and FH.

One hundred and twenty-one patients with idiopathic scoliosis who underwent PSFI were included (41 FH, 80 RAN). Patients underwent FH pedicle screw placement with fluoroscopy assistance, or RAN (Mazor, Medtronic), using a preoperative CT and fluoroscopy-to-CT registration intraoperatively. The mean intraoperative fluoroscopy radiation dose in millisieverts (mSv) and total perioperative radiation dose (preoperative CT + intraoperative fluoroscopy) in mSv were compared by one-way analysis of covariance, controlling for preoperative curve magnitude, body mass index, and number of levels fused. Significance was set at P ≤0.05.

The mean intraoperative fluoroscopy dose was 0.5±0.2 and 0.4±0.1 mSv for FH and RAN, respectively. Mean cumulative radiation doses for FH and RAN were 0.5±0.2 and 12.5±4.7 mSv, respectively. RAN had lower intraoperative radiation than FH ( P <0.001), but FH had a significantly lower cumulative perioperative dosage than RAN ( P <0.001).

RAN had a 1.5-fold decrease in intraoperative radiation but a 25-fold greater total radiation compared with FH, representing lower radiation exposure to the surgeon but a much higher exposure to the patient. Literature demonstrates the potential efficacy of low-dose CT and, paired with our findings, suggests that there is room for improvement in radiation exposure in the robotic field. Surgeons must try to reduce radiation exposure for patients when feasible and reassess surgical practice and imaging protocols.

Level III.