The authors introduce a simple technique and tool to facilitate reduction of atlantoaxial subluxation during posterior segmental screw fixation.
Two types of reduction tool have been designed: T-type and L-type. A T-shaped levering tool was used when a pedicle or pars screw was used for C-2, and an L-shaped tool was used when a laminar screw was used for C-2. Twenty-two patients who underwent atlantoaxial segmental screw fixation and fusion for the treatment of anteroposterior instability or subluxation, using either of these new types of reduction tool, were enrolled. Demographic, clinical, and surgical data, which had been prospectively collected in a database, were analyzed. The atlantodens interval was measured on lateral radiographs, and the space available for the spinal cord was measured on CT scans.
The authors could attain reduction of the atlantoaxial subluxation without difficulty using either type of tool. The preoperative atlantodens interval ranged from −16.9 to 10.9 mm in a neutral position, and the postoperative interval ranged from −2.8 to 3.0 mm, with negative values due to extension-type or mixed-type instability. The mean space available for the spinal cord significantly increased, from 9.5 mm preoperatively to 15.4 mm postoperatively (p < 0.001).
This technique allowed for controlled manipulation and reduction of the atlantoaxial subluxation without difficulty.
Abbreviations used in this paper:ADI = atlantodens interval; JOA = Japanese Orthopaedic Association; NDI = Neck Disability Index; SAC = space available for the spinal cord; VAS = visual analog scale.
Address correspondence to: Jin S. Yeom, M.D., Spine Center and Department of Orthopaedic Surgery, Seoul National University College of Medicine and Seoul National University Bundang Hospital, 166 Gumiro, Bundang-ku, Sungnam 463-707, Republic of Korea. email: email@example.com.
Please include this information when citing this paper: published online June 21, 2013; DOI: 10.3171/2013.5.SPINE12859.
HirabayashiKMiyakawaJSatomiKMaruyamaTWakanoK: Operative results and postoperative progression of ossification among patients with ossification of cervical posterior longitudinal ligament. Spine (Phila Pa 1976)6:354–3641981
HirabayashiK, MiyakawaJ, SatomiK, MaruyamaT, WakanoK: Operative results and postoperative progression of ossification among patients with ossification of cervical posterior longitudinal ligament. 6:354–364, 1981)| false
YoshidaMNeoMFujibayashiSNakamuraT: Comparison of the anatomical risk for vertebral artery injury associated with the C2-pedicle screw and atlantoaxial transarticular screw. Spine (Phila Pa 1976)31:E513–E5172006
YoshidaM, NeoM, FujibayashiS, NakamuraT: Comparison of the anatomical risk for vertebral artery injury associated with the C2-pedicle screw and atlantoaxial transarticular screw. 31:E513–E517, 2006)| false