Expression of Semaphorin 3A after spinal cord injury / 中国骨伤

OBJECTIVE@#To investigate expression of Semaphorin 3A in rats after spinal cord injury and explore possible mechanism of inhibiting of axonal regeneration after SCI.@*METHODS@#Forty healthy female SD rats, 8 weeks old, weighing (210.00±9.88) g, were randomly divided into control group(20 rats in group A) and model group(20 rats in group B). In control group, removal of T@*RESULTS@#After a simple spinal cord transection injury, hemorrhagic necrosis, localized edema, neurodegeneration, necrosis, and cyst formation occurred in the injured area, and glial scar formation occurred in glial cells. Semaphorin 3A expression levels in control group was low in the gray matter area. There was no expression of Semaphorin 3A in the injured area of spinal cord injury in model group 3 days after operation. On the 14th day, the expression of Semaphorin 3A in the injured area of spinal cord injury increased significantly and was at a high level. On the 28th day, the expression of Semaphorin 3A was moderate. On the 42th day, the positive expression of Semaphorin 3A returned to normal level.@*CONCLUSION@#The increased expression of Semaphorin 3A after spinal cord injury may be one of the mechanisms that inhibit axonal regeneration.

Impact of anterior cervical fusion surgeries on adjacent segments: a finite element analysis / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes in the range of motion (ROM) and stress of the intervertebral disc and facet joint of the adjacent segments following anterior cervical corpectomy and fusion (ACCF) and anterior cervical discectomy and fusion (ACDF) using finite element analysis.</p><p><b>METHODS</b>A three-dimensional finite element model of the lower cervical vertebrae was constructed and validated by comparing the ROM of the finite element model against the published data. After the validation of successful modeling, finite element models of ACDF and ACCF were constructed. The ROM and the stress of the intervertebral disc and facet joint of the adjacent segments were compared between the intact lower cervical vertebrae and the cervical vertebrae after ACDF and ACCF.</p><p><b>RESULTS</b>The ROM of the finite element model was consistent with the published data. The total ROM and the ROM of the fusion segments with ACDF and ACCF were significantly decreased compared with the intact cervical vertebrae. In the adjacent segments following ACDF and ACCF, the ROM the adjacent segments and the stress peak of the intervertebral disc and facet joint all increased obviously compared with those of intact cervical vertebrae.</p><p><b>CONCLUSION</b>After fusion surgeries, the total ROM of the cervical vertebrae decreases and the ROM of the adjacent segment increases. The stress peak of the intervertebral disc and facet joint of the adjacent segments also increases to significantly alter the physiological characteristics of the intact cervical vertebrae.</p>

Application of 360 degree circular decompression and transpedicle screw fixation in the treatment of ossification of thoracic posterior longitudinal ligament by posterior approach / 中国骨伤

<p><b>OBJECTIVE</b>To investigate the clinical effects of 360 degree circular decompression and transpedicle screw fixation to treat the ossification of thoracic posterior longitudinal ligament by posterior approach.</p><p><b>METHODS</b>From December 2009 to November 2013, 18 patients with ossification of thoracic posterior longitudinal ligament ossification were treated with 360 degree circle decompression and transpedicle screw fixation by posterior approach. There were 8 males and 10 females,ranging in age from 32 to 67 years old, with an average of 51 years old. Four patients were accompanied with ligamentum flavum ossification. Longitudinal ossifications in 5 cases were located in the upper thoracic vertebra and 13 cases in the middle and lower thoracic vertebra. Five cases were typical type, 4 cases were segmental type, 6 cases were continuous type and 3 cases were mixed type. All the patients had the posterior spinal canal decompression combined with longitudinal ligament resection, interbody fusion with bone graft and internal fixation surgeries. The operation time,blood loss and complications were recorded. JOA score were applied to evaluate the neurological function recovery pre-surgery, 2 days post-surgery and the latest follow-up. The surgery effects were evaluated by Epstein-Schwall method.</p><p><b>RESULTS</b>The operation time ranged from 3 to 6 hours (mean, 4.2 hours). The blood loss ranged from 800 to 4 000 ml (mean, 1 800 ml). All the patients were followed up, and the duration ranged from 6 months to 3 years, with a mean of 1.8 years. The JOA score increased from preoperative 4.30 ± 2.60 to 7.60 ± 2.40 2 days after surgery, and 7.80 ± 1.90 at the latest follow-up (t = 4.61, P < 0.001). The JOA scores between 2 days after surgery and the latest follow-up had no significant differences (t = 0.28,P = 0.78). The neurological recovery rate was 74% 2 days after surgery and 71% at the latest follow-up. There were 4 cases got an excellent result,10 good,3 fair and 1 poor according to Epstein-Schwall evaluation method. Four patients had cerebrospinal fluid leakage, 3 patients had intercostal nerve paralysis or pain, and 1 patient had superficial incision infection. The neurological function in 3 patients became worse in the second day posteratively , and among them, 2 patients were recovered at the latest follow-up and 1 patient had no changes. All the patients got fusion of bone graft and no internal fixation loosening and fractures occurred.</p><p><b>CONCLUSION</b>360 degree circular decompression and transpedicle screw fixation can resect different types of thoracic longitudinal ligament ossification, and can achieve a good clinical effect.</p>

Posterior spinal transpedicular wedge osteotomy for kyphosis due to delayed osteoporotic vertebral fracture in elderly / 中国骨伤

<p><b>OBJECTIVE</b>To evaluate the clinical effects of posterior spinal transpedicular wedge osteotomy for kyphosis due to delayed osteoporotic vertebral fracture in elderly.</p><p><b>METHODS</b>From July 2009 to February 2014,26 patients with kyphosis caused by delayed osteoporotic vertebral fracture were treated with transpedicular wedge osteotomy. There were 10 males and 16 females,aged from 55 to 75 years old with an average of 67 years. There were 1 osteotomy in thoracic vertebra,21 osteotomies in thoracolumbar vertebrae and 4 in lumbar vertebrae. Total 29 vertebrae were involved, 23 cases with single vertebral fracture and 3 cases with double vertebral fractures. Preoperative Cobb angles were 32°~51° with the mean of (42.00 ± 4.75) ° and VAS scores were 6 to 9 points with an average of (8.40 ± 0.75) points. According to the Frankel grade of spinal cord function, 4 cases were grade D and 22 cases were grade E. Intraoperative bleeding, operation time and perioperative complications were recorded, and improvements of Cobb angle were evaluated by X-rays. VAS score and Frankel grade were respectively used to evaluate the pain and nerve function.</p><p><b>RESULTS</b>The average operation time were 155 min (ranged, 120 to 175) and the mean intraoperative bleeding were 1 100 ml (ranged,800 to 1 500). Postoperative at 2 days, Cobb angle and VAS score were (9.60 ± 2.50) ° and (4.00 ± 1.00) points, respectively, ranged from 5° to 15° and 1 to 5 points. VAS score and Cobb angle improved obviously compared with preoperative (P < 0.05), and the improvement rate of Cobb angle was 76%. Frankel grade of 1 case changed from grade E to C, and the others did not become worse. The follow-up period ranged from 3 to 24 months with an average of 16.4 months. At the final follow-up, Cobb angles and VAS score were (11.00 ± 3.50)° and (4.40 ± 1.25) points, respectively, ranged from 5° to 19° and 1 to 6 points. The patient whose Frankel grade E changed to C at 2 days after surgery and changed to grade D at the latest follow-up. Vertebral body fracture below the fusion level happened in 1 case at 3 months after surgery, vertebral body fracture above the fusion level happened in 1 case at 5 months after surgery, and their chest pain symptoms were relieved after symptomatic treatment and anti osteoporosis treatment. All osteotomy levels obtained fusion which confirmed by X-ray and no internal fixation loosening and breakage were found.</p><p><b>CONCLUSION</b>The clinical effect of posterior transpedicular wedge osteotomy for kyphosis due to delayed osteoporotic vertebral fracture was satisfactory, but manipulation during the operation should be cautious and prevent adjacent vertebral body fracture should be pay attention to prevent.</p>

Total vertebral column resection combined with anterior mesh cage support for the treatment of severe congenital kyphoscoliosis / 中国骨伤

<p><b>OBJECTIVE</b>To explore the clinical effects of total vertebral column resection combined with anterior mesh cage support in treating severe congenital kyphoscoliosis.</p><p><b>METHODS</b>From April 2008 to April 2012,21 patients with severe congenital kyphoscoliosis were treated with total vertebral column resection and internal fixation through posterior approach combined with anterior mesh cage support. There were 8 males and 13 females with an average age of 19.4 years old (ranged from 10 to 35). And 6 cases were thoracic segments deformity,13 cases were thoracolumbar segments and 2 cases were lumbar segments, of them, 2 cases were accompanied with Chairs deformity, 6 cases with diastematomyelia, 4 cases with syringomyelia,and 1 case with neurofibromatosis. According to the Frankel grade system, 3 cases were grade C, 5 cases grade D and 13 cases grade E. Blood loss, operative time, and perioperative complications were recorded. Coronal and sagittal Cobb angle, apical vertebral offset distance, sagittal offset, the relative height of shoulders, razor back deformities were measured and analyzed before and after operation.</p><p><b>RESULTS</b>The average operative time was 5.2 h (3.5 to 6.5 h) and blood loss was 2,500 ml (1,400 to 4,900 ml). The 2nd day after operation, apical vertebral offset distance, sagittal offset, the relative height of shoulders, razor back deformities had obviously improved than preoperative (P < 0.05). There was no significant difference in above items between postoperative on the 2nd day and final follow-up (P > 0.05). The corrective rate of kyphosis and scoliosis were (60.97 +/- 6.30)% and (62.24 +/- 5.82)%, respectively. On the first day after surgery,2 cases of Frankel grade E aggravated to grade D, and obtained recovery at 2 week after conservative treatment. And 1 case palinesthesia later,grade D aggravated to grade C and obtained recovery after revision surgery in time. One case complicated with permanent blindness of left eye, 1 case occurred injury of pleura and 2 cases had cerebrospinal fluid leak during operation. All patients were followed up from 9 to 31 months with an av- erage of 18.6 months. At final follow-up,all patients obtained bone union, Frankel grade D in 4 cases and grade E in 17 cases, no correction loss and internal fixation loosening was found.</p><p><b>CONCLUSION</b>Total vertebral column resection combined with anterior mesh cage support can effectively correct kyphosis and scoliosis in severe congenital kyphoscoliosis and can avoid injury of spine cord by spinal crispation, but intraoperative position and neurologic complications should still be considered.</p>