Francesco Costa, Alessandro Ortolina, Luca Attuati, Andrea Cardia, Massimo Tomei, Marco Riva, Luca Balzarini and Maurizio Fornari
Fractures of C-1 and C-2 are complex and surgical management may be difficult and challenging due to the anatomical relationship sbetween the vertebrae and neurovascular structures. The aim of this study was to evaluate the role, reliability, and accuracy of cervical fixation using the O-arm intraoperative 3D image–based navigation system.
The authors evaluated patients who underwent a navigation system–based surgery for stabilization of a fracture of C-1 and/or C-2 from August 2011 to August 2013. All of the fixation screws were intraoperatively checked and their position was graded.
The patient population comprised 17 patients whose median age was 47.6 years. The surgical procedures were as follows: anterior dens screw fixation in 2 cases, transarticular fixation of C-1 and C-2 in 1 case, fixation using the Harms technique in 12 cases, and occipitocervical fixation in 2 cases. A total of 67 screws were placed. The control intraoperative CT scan revealed 62 screws (92.6%) correctly placed, 4 (5.9%) with a minor cortical violation (< 2 mm), and only 1 screw (1.5%) that was judged to be incorrectly placed and that was immediately corrected. No vascular injury of the vertebral artery was observed either during exposition or during screw placement. No implant failure was observed.
The use of a navigation system based on an intraoperative CT allows a real-time visualization of the vertebrae, reducing the risks of screw misplacement and consequent complications.
Francesco Costa, Giovanni Tosi, Luca Attuati, Andrea Cardia, Alessandro Ortolina, Marco Grimaldi, Fabio Galbusera and Maurizio Fornari
The O-arm system in spine surgery allows greater accuracy, lower rate of screw misplacement, and reduced surgical time. Some concerns have been postulated regarding the radiation doses to patients and surgeons. To the best of the authors' knowledge, most of the studies in the literature were performed with the use of phantoms. The authors present data regarding radiation exposure of the surgeon and operating room (OR) staff in a consecutive series of patients undergoing spine surgery.
Radiation exposure data were collected in a series of 107 patients who underwent spine surgery using the O-arm system. The doses received by the surgeon and the staff were collected using electronic dosimeters.
All patients underwent 1–3 scans. The mean radiation dose to the patients was 5.15 mSv (range 1.48–7.64 mSv). The mean dose registered for the scan operator was 0.005 μSv (range 0.00–0.03 μSv) while the other members of the surgical team positioned outside the OR received 0 μSv.
The O-arm system exposes patients to a higher radiation dose than standard fluoroscopy. However, considering the clear advantages of this system, this adjunctive dose can be considered acceptable. Moreover, the effective dose to the patient can be reduced using collimation or minimizing the parameters of the O-arm system used in this paper. The exposure to operators is essentially negligible when radioprotective garments and protocols are adopted as recommended by the International Commission on Radiological Protection.