BACKGROUND: Presently, it is a certain preventive effect of local emplacement of various isolated materials during operation and postoperatively drug-controlled inflammatory reaction on adhesion between epidural and nerve root after laminectomy.OBJECTIVE: To study the preventive effect of chitosan and titanium net on epidural cicatricle adhesion after laminectomy.DESIGN, TIME AND SETTING: Randomized controlled animal study, which was performed in Guiyang Medical College from June to December 2005.MATERIALS: Eighty adult rabbits, weighing (2.0±0.2) kg, were used to establish vertebral plate resection models. Chitosan was provided by Shanghai Qisheng Biological Agent Industry Company, and titanium net by Guizhou Kelun Pharmacology Company Limited.METHODS: Eighty adult rabbits were randomly divided into four groups, including control group (0.5 mL saline), titanium net group (titanium net in the size of 1.0 cm × 0.8 cm was covered on defect region of vertebral plate and fixed on processus spinosus of upper and lower cone, bilateral muscles and soft tissues), chitosan group (2 mL chitosan), and chitosan + titanium net group (combination of chitosan and titanium net). Six rabbits were sacrificed in the 2nd and 4th weeks postoperatively, and eight rabbits were chosen as the samples in the 8th week.MAIN OUTCOME MEASURES: Morphological changes of cicatricle.RESULTS: Cicatricle was clearer in the control group. Titanium net could relieve peripheral cicatricle of dura mater and effectively isolate peripheral cicatricial tissue and spinal dura meter. Chitosan could remarkably prevent from cicatricle adhesion and inhibit inflammatory reaction. The combination of chitosan and titanium net could effectively inhibit proliferation of cicatricle surrounding dura meter.CONCLUSION: Association of chitosan and titanium net can effectively inhibit cicatricle adhesion surrounding dura meter after laminectomy.

Objective To measure the effect of tetrandrineon (Tet) on inflammatory mediators and endogenous neural stem cell proliferation after spinal cord injury (SCI) in rats.Methods A total of 162 Wistar rats were separated into injury group,Tet group and sham operation group according to the random number table,with 54 rats per group.Allen' s method was used for induction of experimental SCI.Animals in Tet group were given Tet (22.5 mg/kg) through the tail vein at 30 min,24 h and 48 h postinjury.The same volume of normal saline was given to other two groups.Spinal cord tissue samples were taken from the rats after injury to measure levels of tumor necrosis factor (TNF)-α,interleukin (IL)-1 β and IL-10,and tissues were examined with HE staining and Nestin immunohistochemistry staining.Results Levels of TNF-α,IL-1 βand IL-10 in injury and Tet groups increased compared to these in sham operation group at 6 h,12 h,1 d,3 d,5 d and 1 week postinjury (P ＜ 0.05).At the same time point,level of IL-10 was higher in Tet group than in injury group,but inversely for TNF-α and IL-1 β (P ＜ 0.05).More Nestin-positive cells were present in injury and Tet groups than in sham operation group at 1 d,3 d,1 week,2 week,3 week and 4 week postinjury (P ＜ 0.05).Additionally,more Nestin-positive cells were found in Tet group than in injury group at 1 d,3 d,1 week,2 week and 3 week postinjury (P ＜ 0.05).Conclusion Tet is effective to relieve inflammatory reaction,increase neural stem cell number and promote neurological recovery after SCI.

ObjectiveTo explore the clinical outcome of one stage posteroanterior decompression and bone implant in the treatment of severe lower cervical spinal bony canal stenosis. Methods The study involved 29 patients with severe lower cervical spinal bony canal stenosis treated with one stage posteroanterior decompression and bone implant from April 2006 to March 2009. There were 11 patients with old fractures, seven with posterior longitudinal ligament ossification and 11 with cervical disc calcification. The course of disease ranged from 2 months to 3.2 years, average 1.4 years. The nerve function was rated as grade B in two patients, grade C in 19 and grade D in eight according to Frankel scale. The average Japanese Orthopaedic Association (JOA) score was 9.8. ResultsAll patients were followed up for 7-28 months (average 15.2 months), which showed bony fusion five months after operation, with fusion rate of 100％. The Frankel grade was increased for average 1.2 grades and the nervous symptoms alleviated remarkably. Mean postoperative JOA score was 13.8 and increased for mean 4.0, with mean amehoration rate of 55.6％. ConclusionsOne stage posteroanterior decompression and bone implant is a safe and effective method for treatment of lower cervical spinal bony canal stenosis, when the intraoperative electrophysiological monitoring can assure the operative safety.

BACKGROUND:Studies have demonstrated that tetrandrine has protection on acute spinal cord injury,but the specific mechanism remains poorly understood.OBJECTIVE:To study the protection of tetrandrine on rat acute spinal cord injury and to study its mechanism from apoptosis pathway.METHODS:A total of 100 rats were randomly divided into 4 groups.All rats were prepared for spinal cord injury models using modified Allen method except that in the sham-surgery group.Methylprednisolone and tetrandrine was injected into rats in the methylprednisolone and tetrandrine groups by tail intravenous injection prior to and at 24,48 hours after model preparation.The same volume of physiological saline was injected in the sham-surgery and model groups.Basso-BeatUe-Bresnahan(BBB score)was recorded at 8 hours,1,3,7 and 14 days after model preparation.The morphological changes of spinal cord injury sites were observed by hematoxylin-eosin staining and the expressions of bcl-2 and bax were determined by immunohistochemistry.RESULTS AND CONCLUSION:The BBB score of methylpradnisolone and tetrandrine groups were significantly higher than that model group at 7 and 14 days(P<0.05),but there were no significant difference between the methylprednisolone group and tetrandrine group(P>0.05).Hematoxylin-eosin staining showed that the spinal cord injured severely at 3-7 days,the injury degree in the methylpradnisolone group and tetrandrine group was slighter than that of the model group,with smaller bax expression and greater bcl-2 expression(P<0.01).The findings demonstrated that,tetrandrine is able to protect neurons from apoptosis and promote the nerve function recovery by inhibiting the expression of Bax and promoting the expression of Bcl-2.Its effect is not inferior to methylprednisolone.

Objective To discuss the therapeutic options for treatment of subaxial cervical dislocation combined with facet locking. Methods There were 49 patients with cervical dislocations including 7 patients with dislocation at C3,4, 15 at C4,5, 14 at C5,6 and 13 at C6,7. Eleven patients were with old dislocation, with duration of dislocation ranging from 2 hours to 61 days. Neurologic status of the patients according to Frankel scale was graded A in 14 patients, grade B in nine, grade C in 10 and grade D in nine. All patients were treated surgically after closed reduction with skull traction. Results The successful reduction rate was 63% for fresh dislocation, with average improvement of 0.65 grade for spinal cord function. All bone grafts got fusion at four months after operation. Conclusion Therapeutic options are based on fresh or old dislocations, paraplegia or not, intervertebral disk injury severity, and reduction or not through traction for patients with lower cervical dislocations.

Objective To discuss the effect of tetrandrine on endogenous neural stem cell proliferation and differentiation after spinal cord injury in rats. Methods 78 rats were randomly divided into 3 groups: control group(n=36), Tet-treated group(n=36), sham-operated group(n=6). Control group and Tet-treated group were adapted with Allen's combat modeling method. Rats in Tet group were injected Ted with a dosage 22.5 mg/kg in 30 minutes, 24 hours and 48 hours after ASCI, and the same dose of saline was injected into injured group as control .Samples were dissected from the spinal cord injury sites at 1 day, 3 days, 1 week, 2 weeks, 3 weeks, 4 weeks after ASCI, and tested by HE staining for morphology and by immunolfuorescence staining for the expression of BrdU and nestin. Results A little Nestin positive cells and BrdU positive cells were found in control group and Tet-treated group at 1 day after injury. A large number of positive cells were found in both groups at 1 week after injury and reached the peak which lasted for 2 weeks and then decreased gradually. The expression of Nestin positive cells and BrdU positive cells in control group and Tet-treated group were decreased significantly at 4 weeks after injury, but were still more than that in sham operation group. The number of Nestin positive cells and BrdU positive cells in Tet-treated group were more than that in control group at each time point after injury. The expression was higher in Tet-treated group than control group at 1 day, 3 days, 1 week, 2 weeks, 3 weeks after injury and had no difference at 4 weeks after injury. Conclusions Tetrandrine could increase the number of Nestin positive cells, BrdU positive cells and endogenous neural stem cells though improving the microenvironment, and it is beneficial for the recovery of spinal cord injury in rats.

Objective To discuss the short-term curative effect and the safety of percutaneous vertebroplasty using high viscosity bone cement for the treatment of severe osteoporotic vertebral body compression fractures. Methods The clinical data of 100 patients with severe osteoporotic vertebral body compression fractures (compression degree>70%), who received percutaneous vertebroplasty by using high viscosity bone cement during the period from December 2010 to May 2013, were retrospectively analyzed. All the patients were followed up for at least one month. Both preoperative and postoperative visual analogue scale (VAS) and quality of life (QOL) scores, as well as the incidence of bone cement leakage, were recorded and the results were used to evaluate the curative effect and the safety of percutaneous vertebroplasty for severe osteoporotic vertebral body compression fractures. Results One week after the treatment, significant pain relief was obtained in 92 patients (92%), VAS scores decreased from preoperative (7.0 ±1.2) to postoperative (2.0±1.5), and QOL scores increased from preoperative (30±5.0) to postoperative (80±18.0);the differences were statistically significant (P<0.01). One month after the treatment, significant pain relief was seen in 91 patients (91%), VAS scores decreased from preoperative (7.0 ±1.2) to postoperative (1.5 ±1.0) and QOL scores increased from preoperative (30±5.0) to postoperative (80±15.0); the differences were statistically significant (P<0.01). No statistically significant differences in VAS scores and QOL scores existed between the data determined at one week after the treatment and the data determined at one month after the treatment (P>0.05). Leakage of bone cement was observed in 40 patients (40%), resulting no severe neurological symptoms; among the 40 patients, intervertebral disc leakage at above and below the vertebral body was detected in 28 patients (70%), vertebral anterior edge leakage was observed in 11 patients (27.5%) and vertebral posterior edge leakage was seen in one patient (2.5%). Conclusion For the treatment of severe osteoporotic vertebral body compression fractures, percutaneous vertebroplasty by using high viscosity bone cement is safe and effective.

Objective To explore the accuracy and clinical efficacy of advanced 3D printing navigation templates in assisting placement of atlantoaxial pedicle screw.Methods A retrospective analysis was carried out on 49 cases of patients with atlanto-axial vertebral fractures and dislocations between June 2013 and June 2016,and all of them were given posterior incision,reduction and internal fixation of atlantoaxial pedicle screw.The patients were divided into advanced 3D printing navigation template group (14 cases),early 3D printing navigation template group (16 cases),and routine pedicle screw placement group (19 cases).Atlantoaxial CT data of patients in advanced 3D printing navigation template group and early 3D printing navigation template group were input into Mimics 17.0,then advanced 3D printing navigation template group and early 3D printing navigation which were used in clinic surgery were designed and printed.The relationship between positions of pedicle screw with the pedicle and bone cortex in plain CT image was observed after operation.The quality of the screw position was assessed and the accuracy of three kinds of screwing methods was compared.The accuracy of the screwing angle was assessed by comparing with the differences between the preoperative designed channel inclination angle and postoperative actual screwing angle.Three groups were compared for differences between operation time,intraoperative blood loss,and scores of cervical nerve scale and visual analogue scale (VAS) of neck and shoulder pain by Japanese Orthopaedic Association (JOA).Results All 49 cases of patients successfully completed the surgery.Patients of the routine pedicle screw placement group,early 3D group and advanced 3D group correspond operation time for 141.2±20.7 min,112.5±12.1 min and 103.1±10.4 min,intraoperative blood loss for 314.0±81.4 ml,243.6±71.2 ml and 181.0+59.1 ml;total accuracy of screwing for 75.0％ (54/72),93.75 ％ (60/64) and 96.43 ％ (54/56).There were statistically significant differences among the routine group,3D group and advanced 3D group in the mentioned programs.There were no statistical differences between advanced 3D group and 3D group in the inclination angle and head tilt angle with the pre-designed values,while there was statistically significant difference between the routine group and the pre-designed value.The accuracy of the inclination angle and bead tilt angle screwing angle were obviously superior in the advanced 3D group and early 3D group to that of the routine group.There were statistically significant differences between preoperative with postoperative VAS scores and JOA scores in the same group,while there were no statistically significant differences among groups in JOA.But there was statistically significant difference between the routine group and the advanced 3D in VAS,and there was no statistically significant difference between the routine pedicle screw placement group and the early 3D in VAS.All three groups of patients had bony fusion of atlantoaxial vertebral body,without loosening,dislocation and fracture of the internal fixators.Conelusion Advanced 3D printing templates in assisting the surgical treatment for atlantoaxial fracture and dislocation can improve the accuracy of pedicle screwing and safety of the surgery,reduce the surgery risk,and obtain satisfied clinical curative effects.

Objective To investigate the clinical efficacy of asymmetric osteotomy via posterior adjacent vertebrae in the treatment of traumatic thoracolumbar kyphotic scoliotic deformity.Methods A retrospective case series study was conducted on the clinical data of 16 patients with traumatic thoracolumbar kyphotic scoliotic deformity admitted to our department from January 2012 to January 2017.There were 10 males and six females,aged (42.5 ±7.6) years (range,20-62 years).According to the location of injured vertebrae,there were two patients with T11,five with T12,six with L1,and three with L2,all of which had scoliosis deformity and obvious low back pain.All patients underwent asymmetric osteotomy via posterior adjacent vertebrae.The operation time and intraoperative bleeding were recorded.The imaging parameters such as kyphosis Cobb angle,scoliosis Cobb angle,distance between C7 plumbline and central sacral vertebral line (C7-CSVL),and distance between C7 plumbline and sagittal vertical axis (SVA) were measured before and after operation.At the same time,the visual analogue scale (VAS),Oswestry dysfunction index (ODI),and SRS-22 scale were used to evaluate the clinical efficacy.The AISA score was used to evaluate the neurological function recovery before and after operation.Results All patients were followed up for (26.3 ± 16.8) months (range,15-65 months).The operation time was (6.0 ± 1.4) hours (range,4.5-9.0 hours),and the intraoperative bleeding was (900.5 ± 360.8)ml (range,800-1600 ml).The kyphosis Cobb angle was improved from (70.3 ± 9.8) °before operation to (12.2 ± 2.9) ° after operation (P ＜ 0.01).The scoliosis Cobb angle was improved from (47.6 ± 11.6) ° before operation to (4.0 ± 0.9) ° after operation (P ＜ 0.01).The C7-CSVL decreased from preoperative (3.1 ±0.8)cm to postoperative (1.2 ±0.4)cm (P ＜0.01),and the SVA decreased from preoperative (5.0 ± 0.9) cm to postoperative (2.9 ± 0.5) cm (P ＜ 0.01).No severe complications such as spinal cord and nerve injury occurred.The VAS decreased from preoperative (6.8 ± 1.0) to (1.9 ± 0.9) points at the last follow up.The ODI decreased from (54.6 ± 4.2) ％ before operation to (8.1 ± 2.5) ％ at the last follow up.The SRS-22 score was increased from (64.6 ±7.5) points before operation to (87.4 ± 3.2) points at the last follow-up.In terms of the ASIA classification,two patients were improved from grade C to grade D after operation,and six patients were improved from grade D to grade E.Conclusion Asymmetric osteotomy via posterior adjacent vertebrae is safe and effective in the treatment of traumatic thoracolumbar scoliosis,with high correction rate of scoliosis and kyphosis at the same time.

BACKGROUND:Posterior atlantoaxial pedicle screw rod internal fixation is the main method for treating atlantoaxial dislocation,and the horizontal crosslink plays an important role in the antirotation ability of the internal fixation system.The new horizontal screw-screw crosslink can effectively overcome the disadvantages of traditional horizontal crosslink,such as inconvenient installation,impact on bone grafting bed,and potential spinal cord injury.However,the biomechanical properties of the new horizontal screw-screw crosslink with different installation modes are still unclear. OBJECTIVE:To investigate the biomechanical characteristics of new different installation modes of horizontal screw-screw crosslink in the C1-C2 pedicle screw-rod fixation and to provide a theoretical basis for optimal installation mode. METHODS:Six fresh human occipitocervical specimens were divided into the intact state group(group A),and the atlantoaxial instability model of type Ⅱ odontoid fracture was established based on the intact state group as the instability group(group B).The C1-C2 pedicle screw-rod fixation was performed on each specimen based on the instability group(group C).In group C,different installation modes of horizontal screw-screw crosslink were successively installed in each specimen,including upper transverse connection(two atlas screw tails)as group D,lower transverse connection(two axis screw tails)as group E,diagonal transverse connection(upper left and lower right for group F,lower left and upper right for group G),and cross transverse connection as group H.The specimen models were tested in order of flexion,extension,lateral flexion and lateral rotation on a three-dimensional motion machine,and the atlantoaxial range of motion of each group of specimens was obtained.Repeated measure analysis of variance was used to evaluate the biomechanical properties of each group. RESULTS AND CONCLUSION:(1)Under six states,the range of motion of groups A,C,D,E,F,G and H was smaller than that of group B,and there were statistically significant differences(P＜0.05).(2)In the flexion and extension states,there was no significant difference among the five types of horizontal screw-screw crosslink groups(P＞0.05).(3)In the left and right rotation directions,there were significant differences in D and E groups compared with F,G and H groups(P＜0.05);there were no significant differences between D and E groups,and F and G groups(P＞0.05),and there were no significant differences in F and G groups compared with H group(P＞0.05).(4)In conclusion,under flexion-extension states,the biomechanical stability of five types of horizontal screw-screw crosslink groups was similar,but under the rotation state,the stability of diagonal horizontal screw-screw crosslink group and cross horizontal screw-screw crosslink group was obviously better than that of transverse horizontal screw-screw crosslink group;however,the stability of diagonal horizontal screw-screw crosslink group is similar to the cross horizontal screw-screw crosslink group,so the former is more worthy of clinical recommendation.