ABSTRACT
OBJECTIVE@#To establish a three-dimensional finite element model of osteoporosis and to study the stiffness recovery of injured vertebrae and stress analysis of adjacent vertebrae after percutaneous vertebroplasty under different perfusion and distribution conditions by simulating fluid flow into the vertebral body.@*METHODS@#A male healthy volunteer was selected. CT scans were performed from T@*RESULTS@#(1) The VonMises stress of T@*CONCLUSION@#Reliable biomechanical model of lumbar vertebral fracture can be established by using CT scanning data through software simulation. Vertebral fracture and vertebroplasty will cause biomechanical changes of adjacent vertebral bodies. With the increase of bone cement injection, the influence of biomechanical changes will increase significantly. Neighbouring vertebral fractures are more likely. For this experiment, percutaneous vertebroplasty has a suitable amount of cement injection of 4 ml.
Subject(s)
Humans , Male , Biomechanical Phenomena , Bone Cements , Finite Element Analysis , Fractures, Compression/surgery , Lumbar Vertebrae/surgery , Osteoporotic Fractures/surgery , Spinal Fractures/surgery , VertebroplastyABSTRACT
<p><b>OBJECTIVE</b>To discuss the value of Gemstone Spectrum Imaging (GSI) CT anterior spinal artery angiography in the patients with cervical spinal cord injury, and to evaluate the correlation between the change of the blood flow of the anterior spinal artery and the postoperative recovery of nerve function.</p><p><b>METHODS</b>From January 2014 to June 2016, thirty patients who underwent cervical open door laminoplasty for spinal cord injury were retrospective analyzed and included 21 males and 9 females with an average age of (46.4±9.7) years old ranging from 33 to 59 years. Within 2 weeks after injury, open door laminoplasty was performed through cervical posterior approach. Among them, there were 8 cases of 3 segments of open door decompression, 18 cases of 4 segments, 4 cases of 5 segments. GSI CT were performed at 3 days before operation and 5 days after operation. The anterior spinal artery was reconstructed and evaluated the improvement of blood flow after operation. The cervical JOA score was calculated at 1 day before operation, 5 days after operation and 1, 6 and 12 months after operation, and the JOA score improvement rate of the corresponding follow-up points was calculated.</p><p><b>RESULTS</b>All patients were followed up for 12 to 30 months with an average of (17.4±7.6) months. The iodine content ratio (ASA/VA) of the anterior spinal artery before and after operation was 0.75±0.20 and 0.89±0.02 respectively, the postoperative improvement was significantly higher than that before operation(<0.01). The average ASA/VA improvement rate was(21.05±12.45)% after operation. There was a positive linear correlation between the improvement of blood flow and the improvement of JOA score at 1, 6 and 12 months after operation.</p><p><b>CONCLUSIONS</b>GSI CT anterior spinal artery angiography is safe and feasible, the imaging is satisfactory, it can quantitatively evaluated the blood flow of the anterior spinal artery. There was a positive linear correlation between the improvement of blood flow in anterior spinal artery and the recovery of neurological function. Early postoperative improvement of blood flow in the anterior spinal artery can be used as a reference index for predicting the recovery of neurological function in patients.</p>
ABSTRACT
<p><b>OBJECTIVE</b>To study the clinical characteristics of the intradural extramedullary tumor in the spinal canal, as well as the application of internal fixation technique to restore the spinal stability in the surgical treatment of intradural extramedullary tumor in the spinal canal through posterior approach.</p><p><b>METHODS</b>Among 24 patients receiving the tumor resection through posterior approach, 14 patients were male and 10 patients were female, ranging in age from 12 to 68 years, with an average of 40 years. Fourteen patients were treated with internal fixation and autogenous bone graft after tumor resection, and other 10 patients without internal fixation and autogenous bone graft.</p><p><b>RESULTS</b>All the patients underwent one-stage resection of the tumor. During the follow-up period ranged from 6 months to 3 years (average 22 months), no recurrence of the tumor was found and the injury of spine cord did not aggravate, no vascular or nerve-root injury after the operation. The Frankle grades were improved by 1 to 3 degrees. Bone fusion formed at the corresponding bone grafted place. And there was no instrument broken or loosening.</p><p><b>CONCLUSION</b>After the intradural extramedullary tumor is resected, internal fixation and autogenous bone graft can restore the stability of spine.</p>