Intraoperative computed tomography with integrated navigation in percutaneous iliosacral screwing

Background: Iliosacral screw fixation has generally been accepted as a treatment for unstable pelvic fractures with posterior sacroiliac joint disruption despite a 2-16% rate of screw malposition. The integration of an intraoperative computed tomography (iCT) with a navigation system was utilized in percutaneous sacroiliac screwing to provide an alternative. Methods: From October 2010 to November 2011, thirteen patients presented pelvic fractures with posterior ring disruption (lateral compression type 2-3 [n = 12] and vertical shear type [n = 1] by Young-Burgess Classification) and underwent percutaneous iliosacral screwing using an iCT integrated with navigation system. The perioperative data and radiographic outcomes of the patients were collected and analyzed. Results: Navigation times ranged from 10 to 45 min (mean of 21.2 ± 10.6 min). Radiation exposure to the skin utilizing integrated navigation system ranged from 23.5 to 28.1 mGy (mean of 26.4 ± 1.5 mGy), and the dose associated with examining the screw position ranged from 22.5 to 26.8 mGy (mean of 25.5 ± 1.1 mGy). Effective dose of radiation ranged from 9.26 to 17.43 mSv (mean of 13.16 ± 2.52 mSv). The iCT demonstrated iliosacral screws in adequate position (i.e., no penetration or encroachment of the neuroforamen or cord). No neurologic or vascular injury occurred in these cases. Conclusions: An iCT with an integrated navigation system provided accuracy for percutaneous iliosacral screwing. In addition, the accumulated dose was minimized for surgeons. However, effective dose of radiation in iCT with an integrated navigation system group was higher than fluoroscopic-assisted iliosacral screwing in hands of the same group of surgeons. No neurologic complications occurred. The iCT with an integrated navigation system provided an alternative to percutaneous iliosacral screwing.