Abstract:

BACKGROUND: The pedicle screw internal fixation is usually used for treatment of atlantoaxial instability. The implanted location and angulation of these pedicle screws are statistically determined by anatomy data. But this method always leads to inaccurate implant of the screw into the injured atlantoaxial.
OBJECTIVE: To evaluate the security and reliability of pedicle screw implantation by individual design and anatomical localization for treatment of atlantoaxial instability.
METHODS: A total of 16 cases with atlantoaxial dislocation were fixed with atlantoaxial pedicle screw by location through inferior and inner wall of atlas and superior and inner wall of axis. Combined with the first image measurement, the implanted location, angulation and screw length of atlas were determined, and pedicle screw fixation system was implanted.
RESULTS AND CONCLUSION: All the 16 patients were implanted successfully with atlantoaxial pedicle screw. The post-implantation X-ray film and CT image showed the position of pedicle screw was well. They were followed up for 9 to 24 months after the operation. All of them obtained bony union with improved function of the spinal reached 84.6% which containing excellent in 6 cases (46.2%), good in 5 cases (38.5%) and moderate in 2 cases (15.4%). No aggravation was observed, and no complications such as vascular injury, either. It indicates that pedicle screw implantation by individual design and anatomical localization for treatment of atlantoaxial instability has the characteristics of accurate implanted location and angulation, and the security and reliability of pedicle screw implantation.