Objective:To develop a nomogram predictive model on the basis of identification of the risk factors associated with failure in repositioning the dislocation of the subaxial cervical spine with locked facets by skull traction.Methods:A retrospective study was conducted of the clinical data of the patients who had been treated for dislocation of the subaxial cervical spine with locked facets at Department of Orthopaedic Trauma, The Hospital Affiliated to Guizhou Medical University and Department of Spine Surgery, The People's Hospital of Guizhou Province from January 2014 to December 2022. The clinical data from The Hospital Affiliated to Guizhou Medical University were used as a training set (156 cases) and those from The People's Hospital of Guizhou Province as an external validation set (54 cases). Univariate analysis and multi-variate logistic regression analysis of the training set were conducted to screen out independent risk factors associated with the failure in repositioning the dislocation of the subaxial cervical spine with locked facets by skull traction. A nomogram predictive model was thus constructed and assessed by the receiver operating characteristic (ROC) curve, calibration curve, and decision curve. Internal validation of the training set and external validation set was used to evaluate and validate the model.Results:The multivariate logistic regression analysis revealed that cervical Ⅰ grade dislocation ( P=0.002), cervical Ⅱ grade dislocation ( P=0.007), low segment affected ( P=0.042), unilateral facet locked ( P=0.027), and the ASIA grading of spinal cord injury ( P=0.008) were the independent risk factors associated with the failure in repositioning the dislocation of the subaxial cervical spine with locked facets by skull traction, based on which the nomogram model with a C-index of 0.88 was constructed to predict the failure in repositioning the dislocation of the subaxial cervical spine with locked facets by skull traction. Analysis of the ROC curve of the training set showed an area under the curve (AUC) of 0.88, indicating good accuracy of the nomogram model. Analysis of the calibration curve showed high consistency between the probability of the nomogram model predicting the failure in repositioning the dislocation of the subaxial cervical spine with locked facets by skull traction and the actual probability of traction reposition failure. Analysis of the decision curve showed that application of the nomogram model led to good benefits when the net benefit threshold for the failure in repositioning the dislocation of the subaxial cervical spine with locked facets by skull traction was 0.03 to 0.84. Analysis of the ROC curve of external validation set showed an AUC of 0.79, indicating good accuracy of the nomogram model. The training set showed a C-index of 0.87 after 1,000 internal verifications by the Bootstrap method, indicating good discrimination of the nomogram model. Conclusions:Cervical Ⅰ grade dislocation, cervical Ⅱ grade dislocation, low segment affected, unilateral facet locked, and incomplete spinal cord injury are independent risk factors associated with failure in repositioning the dislocation of the subaxial cervical spine with locked facets by skull traction. A nomogram model has been successfully constructed which can predict the failure in repositioning the dislocation of the subaxial cervical spine with locked facets by skull traction. Validation and evaluation of the nomogram model have demonstrated its good predictive value.

Lumbar degenerative disease is one of the most common diseases in orthopaedic clinics, and the chronic low back pain caused by it seriously affects patients' living quality. Currently, intervertebral fusion and rigid fixation are the main surgical methods for lumbar degenerative disease. Although the intervertebral fusion and rigid fixation can achieve a higher fusion rate, due to the stress concentration of adjacent segments, the adjacent segment degeneration may occur and make the patient's satisfaction rate much lower than the imaging fusion rate. Dynamic fixation is a new fixing concept, which can control the abnormal motion of the spine segment while retaining part of the movement of the fixed segment. Moreover, dynamic fixation is also beneficial to reduce the degeneration of adjacent segments and the incidence of breakage of internal fixation. Nowadays, various lumbar transpedicular dynamic fixation systems have appeared on the market. Most of these transpedicular dynamic fixation systems are derived from the design of pedicle screws and rods used in spinal fusion surgery in the 1980 s and 1990 s. The original intention of their design is to stabilize the abnormal segments and reduce the pressure on degenerated intervertebral discs and facet joints, while maintaining the normal movement of relevant segments. By reviewing the biomechanical research, clinical efficacy, existing problems and advantages and disadvantages of common backward lumbar transpedicular dynamic fixation systems, this article intends to provide new ideas for the improvement of the backward lumbar transpedicular dynamic fixation system design, as well as offering surgical treatment strategies for clinicians.

Objective The aim of this study was to investigate the effect of TSP-1 gene on angiogenesis in human osteosar-coma and its mechanism of action. Methods MG-63 cells were transfected with constructing pBPLV-shRNA-TSP-1 vector and pBPLV-TSP-1 expression vector. Cell viability was measured by CCK8,and its invasive ability was measured by Transwell assay. The expression of CD36 in intracells was detected by immunofluorescence. The expression levels of TSP-1,CD36,p38MAPK,VEGF, VEGFR-1,EGF and PDGF were detected in MG-63 cells by qRT-PCR and Western blot. Results The cell viability and inva-sion ability were significantly increased after transfected pBPLV-TSP-1 vector compared with the empty vector group(P<0. 05), and significantly decreased after transfected pBPLV-shRNA-TSP-1 vector( P<0. 05). The expression of TSP-1,EGF,P38, PDGF,VEGF and VEGFR -1 at mRNA and protein levels was significantly increased after transfection pBPLV -TSP -1 ( P <0. 05),and significantly decreased after transfection pBPLV-shRNA-TSP-1 vector(P<0. 05). Conclusion TSP-1 gene can promote the proliferation and invasion of MG-63 cells,and promote the formation of human osteosarcoma,indicating its mechanism related to the increase of growth factors EGF,VEGF,PDGF and activation of P38-MAPK pathway.

Objective To verify BMP-2 and VEGF gene activated nanobone paste can effectively enhance the vertebral bone of ovariectomized goat.Methods From January,2011 to May,2016,the goats had been neutered by ovariectomy 6 months earlier to induceosteoporosis.Then surgery to established the model of vertebral bone defected with nanobone implanting,and the operation vertebrae divided randomly into 3 groups:control group,nanobone group and double gene activated nanobone group.Three months after operation the goats were sacrificed and removed the vertebrae.Micro CT analysis of micro three-dimensional structure of trabecular bone,scanning electron microscope (SEM) analysis of the two-dimensional structure of the vertebrae,the structure of trabecular bone was evaluated by movat pentachrome staining.Results The dual gene activated nanobone group compared with the nanobone group,the bone volume fraction (BV/TV) significantly increased (85％ at 1.2 mm vs 43％ at 1.2 mm,P ＜ 0.05);the dual gene activated nanobone group compared with nanobone group,in the largest ROI (1.2 mm),TbTh increased 10.9％ (374 ± 26.2 μm vs 337 ± 22.3 μm,P ＜ 0.05);Trabecular distribution coefficient (TbPf) was significantly decreased (7.519 ± 0.184 mm-1 vs 7.529 ± 0.261 mm-1,P ＜ 0.05);In the largest ROI (0.8 mm),trabecular distribution coefficient (TbPf) was significantly decreased (283 ± 36.4 μm vs 327 ± 31.2 μm,P ＜ 0.05),In the largest ROI (0.8 mm),the trabecular bone volume (Tbn) was increased 20％(1.404 ± 0.283 mm-1 vs 1.173 ± 0.224 mm-1,P ＜ 0.05);Cortical thickness over the implantation area showed asignificant increase of 43％ in vertebrae(P ＜ 0.05);The histological analysis revealed a more extensive osseointegration of the dual gene activated nanobone group,with the presence of anabundant osteoid tissue and an osteoblastic celllining.Conclusion BMP-2 and VEGF gene activated nano bone paste can effectively enhance the vertebral bone of ovariectomized goat.

BACKGROUND:The bone morphogenetic protein 2 (BMP2)/vascular endothelial growth factor (VEGF) dual gene activated nanobone putty has been constructed in the previous experiments.
OBJECTIVE:To investigate the effects of osteogenesis and osteogenic gene expression in mice by implanting BMP2/VEGF dual gene activated nanobone putty.
METHODS:Twenty-four Kunming mice (48 sides) were randomly divided into four groups. Animals in each group (12 samples) were injected different materials into the right thigh muscle pouches:nanobone putty+hBMP2/VEGF plasmid;nanobone putty+hBMP2 plasmid;blank plasmid+nanobone putty;nanobone putty only. The effects of osteogenesis were evaluated by radiography, histology and molecular biology analysis in 2, 4 weeks after operation.
RESULTS AND CONCLUSION:Bone-like tissues were observed in groups of nanobone putty+hBMP2/VEGF plasmid and nanobone putty+hBMP2 plasmid after operation. There was apparent BMP2 and VEGF mRNA expression in group of nanobone putty+hBMP2/VEGF plasmid. Group of nanobone putty+hBMP2/VEGF plasmid was significantly better than group of nanobone putty+hBMP2 plasmid in the alkaline phosphatase levels, the speed of osteogenesisas and amount of new bone (P<0.05). Groups of blank plasmid+nanobone putty and nanobone putty had no obvious osteogenesis performance. Either BMP2/VEGF dual gene activated nanobone putty or BMP2 gene activated nanobone putty had the osteogenic ability in vivo. And the former was significantly enhanced in the speed and quality of osteogenesis.

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.

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.

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.

BACKGROUND: For its extensive sources and specific biological characteristics, heterogeneous deproteinized bone (DPB) as the tissue-engineered scaffold material gets a good application prospect in repair of large segmental bone defects.OBJECTIVE: To prepare scaffold material by compositing modified heterogeneous DPB with recombinant human bone morphogenetic protein 2 (rhBMP2) and evaluate the osteogenic ability in repairing large segmental long bone defects in large-sized animals.METHODS: Twenty-four goats were randomly and evenly divided into three groups: DPB, autologous bone, and DPB+rhBMP2. Bone defects (20% in length) were made in the middle and lower segments of the right tibia of each goat, and according to group design,different bone grafts were implanted and fixed using semi-ring slot external fixer. At 4-24 weeks after surgery, X-ray examination was performed once every other 4 weeks. At 24 weeks after surgery, newly formed bones were taken out for determining the repair effects of bone defects through duat-energy X-ray analysis, histological observation, and biomechanical analysis.RESULTS AND CONCLUSION: The prepared DPB exhibited a three-dimensional porous structure, with a porosity of (78.5±6.45)% and pore size of (472.5±7.02) μm. Time-dependent bone repair was found in each group. Results regarding anti-compression test, three-point anti-bend test, and anti-torsion test were greatest in the autologous bone group, followed by the DPB+rhBMP2 group, and lastly the DPB group. There were no significant differences in tibial bone density, bone mineral content,anti-compression pressure and ultimate pressure, anti-bending load and ultimate toad, anti-torsion torque and ultimate torque between autologous bone group, DPB+rhBMP2 group and normal bone control group. These findings indicate that modified heterogeneous DPB composited with rhBMP2 has osteogenic ability equivalent to autologous bone in repairing large segmental long bone defects in goat tibias. Therefore, it can be applied as tissue-engineered scaffold material.

BACKGROUND: There are few reports about vascularization in the repairing of bone defect by heterogeneous deproteinized bone.OBJECTIVE: To verify the vascularization characteristics of heterogeneous deproteinized bone, tissue engineering scaffold material, in the repairing of large segmental bone defect.DESIGN, TIME AND SETTING: The randomized controlled animal experiment was performed between March 2005 and February 2007 at the Third Military Medical University, Chongqing, China.MATERIALS: Twenty-four 10 to 12 months old goats, weighing (22.5±2.5)kg, were obtained from the Animal Center of the Third Military Medical University, Chongqing, China. Segmental bone defects of 20 percent right tibia middle and inferior diaphysis of the 24 goats were made.METHODS: The 24 goats were divided into test group (n=16) and control group (n=8) randomly. Goats in test group were implanted with deproteinized bone+autologous MSCs+recombinant human bone morphogenetic protein-2 (rhBMP-2), goats in control group were implanted with autograft bone, and all fixed with half-ring sulcated external fixator. Every 4 weeks, 3 goats were killed after ink perfusing through femoral artery. A thick slice of new bone tissue was made to observe the vascularization.MAIN OUTCOME MEASURES: Vascularization of new bone observed through gross anatomy and imaging; vascular network of new bone observed through thick section, blood vessel amount and area measured by Image-proplus really image analysis software.RESULTS: No goat was infected or dead. Animal soft tissue was dyed black, blood vessels'size, ditribution and network structure were observed in subcutaneous tissue, fascia and periosteum. At 4 weeks postoperation implant margin became crude in the defect area; at 8 weeks postoperation transparent bone absorbing area of different size and irregular shape appeared; after 12 weeks postoperation high-dense calcification shadow appeared at the ends of defect bone and new bone connected with the ends completely. On 4 to 24 weeks postoperation, the blood vessel amount became large, alignment became regular, and their size and distribution became uniform. It showed no significant difference in blood vessel amount and area between 2 groups (P>0.05).CONCLUSION: Composite of heterogeneous deproteinized bone+autologous MSCs+rhBMP-2 has the same vascularization degree. of autogeneous bone graft in repairing of large segmental tibia defect.