Vertex technique for treatment of atlantoaxial instability:Clinical outcomes and implant features / 中国组织工程研究

ABSTRACT

This paper is aimed to explore the correlation of clinical outcomes with material science features of implant in the treatment of atlantoaxial instability by the Vertex technique.A total of 26 cases with atlantoaxial instability and dislocation were enrolled from the Affiliated Hospital of Luzhou Medical College between January 2004 and January 2006.They all underwent the internal fixation via posterior cervical pathway and atlantoaxial fusion in Vertex system that was produced by American Sofamor Danek Company.The intraoperative complications and postoperative neurological recovery of each case were documented.Dynamic radiograph and digital tomography were used to evaluate the extent of the atlantoaxial vertebrae stability.①The result of X-ray showed that bony fusion was successful in 22 patients during 3-month follow-ups,3 patients during 6-month follow-ups,and 1 case after implantation following bony resorption.②There was no deterioration of spinal cord injury and the JOA scores of neurofunction increased from 3-17 points(mean 6.8 points) to 5-17 points(mean 14.8 points) ,with the rate of improvement as 83%.③All 26 patients were normal in the movements of expansion and flexion,but the rotation was partly limited.There were 18 cases rotate in 120?,6 cases in 100? and 1 case in 60?.Vertex system is effective in dealing with internal fixation via posterior cervical pathway.Due to the connection with stick by multiaxial screw,Vertex system presents superiority in clinic,such as secure fixation,random length and convenient connection.Vertex system internal fixation is effective in dealing with atlantoaxial instability and dislocation.