Radiation Exposure in Single Level Lumbar Fusion: Our Experience in Robotic Guidance Compared to Literature Review of Minimally Invasive Fusions

Abstract

Introduction Lonizing radiation used in fluoroscopy leads to significant radiation exposure to the surgeon, operating room staff, and the patient. Low dose exposure can cause skin burns, nausea, and cataracts where as in sufficient doses increase the lifetime risk of cancer among spine surgeons and patients. Moreover, accumulating low dose exposure over a lifetime may lead to heritable changes at a genetic level. Minimally invasive lumbar fusion, though becoming increasingly popular has significant exposure to radiation. Robotic guidance is the latest tool in spinal fusions and this study focuses on radiation exposure in single level lumbar fusions performed at our institution as compared with literature data. Material and Methods Seventy patients who underwent robotic guided lumbar fusion (Renaissance, Mazor robotics) performed by a single surgeon were analyzed retrospectively for radiation exposure. The age of patients ranged from 38 to 80 (mean, 56 years). Robotic guidance data included execution rate, accuracy of guidance, total surgical time, and time required for robotic guidance. Radiation-related data included the average preoperative computed tomographic effective dose, radiation dosage for calibration, registration, placement of Kirschner wires, and total procedure radiation time. Results Average operative time was 134.7 minutes (82–150). Mean robotic guidance took 16 minutes. Average operative radiation time was 6.2 seconds (5.2–8.6). The screw execution rate was 99%, with an accuracy of 99.5%. Mean radiation exposure dosage to the operating room was 3.7 mgy (3.1–5.2mgy) in robotic guided patients. This exposure is relatively 20 times lesser when compared with published data on radiation exposure in minimally invasive lumbar fusions. Conclusion Radiation exposure to the surgeon and the operating room staff in our series of single level lumbar fusion using robotic guidance was significantly lower than other published results on fluoroscopy guidance and navigated fusion. Robotic guidance reduces the radiation exposure maintaining a high accuracy rate, thereby promising as a safer alternative.