2012 Volume 26 Issue 2 Pages 227-235
Purpose : To report technical points in posterior upper cervical fixation using C1 lateral mass screw.
Materials and Methods : Thirty-seven consecutive cases of cervical spine instability underwent posterior cervical fixation with C1 lateral mass screw over the past 8 years ; there were 19 men and 18 women with a mean age of 66.1 years (range, 27-90). All cases received a comprehensive evaluation before surgery, including vascular assessment using computed tomography (CT) angiography. Preoperative radiological measurement and intraoperative dissection of the upper dorsal cervical field were performed. C1 lateral mass screw was inserted with the help of a navigation system and fluoroscopy. The posterior arch of the C1 was fixed using tape to avoid spinal-cord injury during C1 screw insertion. Clinical outcomes were determined according to the Japanese Orthopaedic Association scoring system and Frankel grading system. Most of these screws were inserted bicortically and connected with axial pedicle/laminar screws. Atlantoaxial midspace was grafted with iliac bone with polyester tape, by using a modified Gallie or McGraw method.
Results : A total of 74 C1 lateral mass screws were placed, as planned, before surgery without any neural or vascular injury.
Conclusion : Complications associated with C1 lateral mass screw fixation can be minimized by the careful image analysis before surgery and meticulous intraoperative exposure and cautious screw insertion. Although posterior fixation using C1 lateral mass screw is a useful procedure for stabilizing and reconstructing the upper cervical spine, surgeons should recognize the surgical indications, benefit, and possible risks.
