Medium-term Follow-up Of Thoracolumbar Fractures After External Skeletal Fixation And Percutaneous Vertebral Bone Graft

Objective: To investigate the medium-term clinic outcome of thoracolumbar vertebral burst fractures after neotype external spinal skeletal fixation (Ne-ESSF) and percutaneous vertebral bone graft (PVBG) : 1. The orthotics reposition effect of ESSF after thoracolumbar vertebral burst fracture (THBF), and the loss of reposition after the ESSF removed. 2.The indirect decompression ability of spinal canal and it's remodeling situation; 3. The outcome of vertebral bone graft through pedicle (PVBG), and analysis adjacent segment degeneration.Method: Between January 2007 and December 2008, there were 39 patients with THBF underwent Ne-ESSF and PVBG. 21 men and 18 women had a mean age of 35.6 years old(16-49 years old)at the time of surgery. Observe and analysis the patients with THBF treated with the Ne-ESSF and PVBG, and their information were integrated. 1. Classification fracture type and grading nerve function according to American Spinal Injury Association (ASIA ) damage grade standard, observe the change of their nerve function before and after treatment; 2. According to the sagittal position X film of preoperative, postoperative, before removal of external fixation and the last follow-up, to measure the height of anterior vertebral and the change of kyphosis, and to explore the principle and ability of orthotics reposition by spinal fixation, observe the lost situation of orthotics results and analysis it's reasons; 3. According to the spiral CT information of preoperative, postoperative and follow-up, to analysis the indirect effect to spinal canal reposition of spinal fixation,Result: The mean follow-up period was 37.6 months (30-47 months).1. By ASIA scale, there were 8 patients with D grade nerve function preoperative, and then recover to E grade between 3 weeks to 3 months after surgery without aggravation; 2. The rate of anterior vertebral height lose (RAHL)and Cobb angle were respectively 37.5±13.5%,16.5±8.0°, postoperative, 3 months after operation and the time when follow-up were respectively 3.0±3.5%,6.1±4.7%,8.5±5.9%,3.1°±4.9°,3.8°±5.0°,5.5°±5.2°; and the statistics show that p<0.05 when compare the RAHL before and after operation, and when compared postoperative and 3 months after operation, p>0.05, postoperative and when the time of follow-up, p<0.05; Cobb angle show that preoperative and postoperative, p<0.05, postoperative, 3 months after operation and when the time of follow-up, p>0.05; the RAHL and Cobb angle were lost when followed-up, but the loss rate was minor. 3. Spinal canal stenosis was 43.4±15.3% preoperative, and postoperative, 3 months after operation and when the time of follow-up were respectively 10.7±6.2%,10.2±5.9%,9.8±5.6%, compared preoperative and postoperative, p<0.05, postoperative, 3 months after operation and when the time of follow-up, p>0.05; and we observed the phenomenon that the small bone fragments in spinal canal were dissolving and absorbing, as well as the spinal canal remodeling. 4. By examine of MRI to 7 patients when the last follow-up, we can see the close disc of the rupture endplate were degenerated, T2 showed a low signal, and some patients appeared a narrow intervertebral and spontaneitily fused in front of the vertebral body.Conclusion:1. The effect of orthotics to anterior vertebral height and Cobb angle were favorable, and there were a little lost in follow-up; bone graft in vertebral can integrated well to normal bone, but could not prevent the lost of anterior vertebral height. 2. The Ne-ESSF could indirectly complete decompression, and ameliorate the rate of canal stenosis, to effectively reserve the remnant function of spinal cord, promote the function recovery of incomplete damaged spinal cord. 3. After indirect decompression reposition through the Ne-ESSF, that can effectively maintain the reset effect of spinal canal. And the free fragment bone in spinal canal would fuse, the spinal canal would be remodeling again. 4. The change of adjacent disc of the damaged vertebral mainly concern to whether the endplate damaged and the extent of damage; the external fixation has no obviously affect to the near segments.