枢椎

Results: 13 cases with 19 bone broken points,the positions are at dens ,side plank of atlas,occipital,plank of axis,processus spinosus etc.23 cases with axis and atlas half dislocation.Of which,16 cases were with pure dislocation,7 cases with rotating dislocation,11 cases were with swollen at the side of vertebra,2 cases with depressing of vertebral artery,5 cases with continued narrowing of vertebral canal.

结果：13例共见19处骨折，部位分别为齿状突、寰椎侧块、枕骨、枢椎椎板、棘突等，寰枢关节脱位23例，其中单纯性脱位16例，旋转性半脱位7例，11例合并椎旁血肿，2例见椎动脉受压，5例继发性椎管狭窄。

The front suture width of axis and atlas joints and the shift degree of dens were also measured.results: 13 cases with 19 bone broken points,the positions are at dens ,side plank of atlas,occipital,plank of axis,processus spinosus etc.23 cases with axis and atlas half dislocation.of which,16 cases were with pure dislocation,7 cases with rotating dislocation,11 cases were with swollen at the side of vertebra,2 cases with depressing of vertebral artery,5 cases with continued narrowing of vertebral canal.conclusions: ct has the advantage of quickness,safety and high density discerning,it can reveal details of acute axis and atlas damages,so it has great importance to treatment scheme making and to the prognosticate.

结果：13例共见19处骨折，部位分别为齿状突、寰椎侧块、枕骨、枢椎椎板、棘突等，寰枢关节脱位23例，其中单纯性脱位16例，旋转性半脱位7例，11例合并椎旁血肿，2例见椎动脉受压，5例继发性椎管狭窄。结论：ct具有快捷、安全、密度分辨率高等优点，可明确急性寰枢关节损伤细节，对制定治疗方案及估价预后具有重要作用。

Results In 7 cases of odontoid process fracture, X-ray demonstrated 4 cases and CT demonstrated 5 cases, whereas the spiral CT reconstruction diagnosed 7 cases, which could display the displacement of fracture clearly. The X-ray and CT showed asymmetric space between left and right gaps of atlantoaxial joint in 6 cases, while spiral CT reconstruction showed normal and excluded the possibility of atlantoaxial dislocation. There was one case of lateral atlantoaxial joint dislocation, which was demonstrated by the spiral CT reconstruction clearly but not by the X-ray and CT scan. There were 3 cases of atlantoaxial congenital deformity (1 case of absence of both posterior arch of atlas and odontoid process and 2 cases of maldevelopment of the odontoid process), which were displayed clearly by spiral CT reconstruction, but misdiagnosed as odontoid process fracture and atlantoaxial subluxation by X-ray and CT scan.

结果 7例齿状突骨折中，X线显示4例，CT显示5例，CT重建确诊7例，且清楚显示骨折移位情况；6例X线、CT显示寰枢椎左右间隙不对称，通过CT重建排除寰枢关节半脱位；寰枢外侧关节脱位1例，CT重建可清楚显示，而X线片和CT平扫均未能显示；寰枢椎畸形3例，分别为齿状突、后弓缺如1例，齿状突发育不良2例，CT重建均能清楚显示，而X线、CT均误诊为齿状突骨折、寰枢椎半脱位。

Results: Under the two boundary conditions, finite element analysis results demonstrated that the ossification degree of the subdental synchondrosis did not obviously influence the high stress distributions, as well the maxium von Mises equivalent stress.

结果：两种约束条件下，枢椎有限元计算预测结果发现枢椎软骨基质的融合程度对枢椎高应力集中带分布无明显影响，最大von Mises等效应力值改变亦不明显。

Results Seven cases were basilar impression,nine cases were dearticulation of atlantoepistrophic articulation,and five caces were Chiari abnormity.In the X-ray pictures,it showed the abnormal form of the atlas and axis,it also showed the Chamberlain line, according to which we could diagnose the basilar impression.

结果 21例中，颅底凹陷为7例，寰枢椎脱位9例，Chiari畸形5例。X线平片主要表现为寰椎、枢椎形态构异常，并且能显示Chamberlain线，借此可作出颅底凹陷的诊断。

Methods A total of 15 cases were fixed and fused with lateral mass screw of atlas and vertebra dentata pedicle screw.

方法采用寰椎侧块螺钉与枢椎椎弓根螺钉技术对15例寰枢椎不稳的患者进行固定。

The MPR was used to measure the height and width of posterior arch in the point of vertebra artery overpass, the height of lateral mass benenththe posterior arch and the height and width ofC2 interarticular isthmus.

结果 寰椎椎动脉沟处后弓高度为4.54±1.17mm，椎动脉沟处后弓宽度为8.69±1.12mm，寰椎后弓下侧块高度为4.98±1.07mm，枢椎峡部高度6.95±2.24mm，枢椎峡部宽度6.75±1.39mm，男、女2组之间没有统计学差异。

The odontoid vertebra space in the model was divided into lattices and the stress area of the odontoid vertebra was identified by force loading and analyses. It was found that the structure of the stress concentration area was closely related to the development of split sections. Therefore,when the odontoid process is attacked by the external force along its vertical plane,its waist is likely to break and type II fracture occurs. And the break also possibly appears in its base,in this way,type HI fracture occurs.

确定其材料性质、单元类型并控制好网格划分精度后，通过力的加载与分析，找出枢椎的结构应力区，根据结构的应力集中区与其断裂时断裂面走向的密切关系，从而判断出当外部载荷沿齿突中性矢状面不同角度作用，即齿突受到来自其矢状面的外部冲击时，容易在齿突腰部发生断裂，形成枢椎齿突Ⅱ型骨折，也可能在基底部发生断裂，形成枢椎齿突Ⅲ型骨折。

From the simulations, we can see the distributions and transmission of strain and stress in model under different loadings, and the results explained the fractures very well. 4. Similarly, a axis FEM model was constructed to simulate the axis fracture, emphasized on the odontoid process. Three kind of odontoid process fracture were analysed on this model, which occurred respectively on the tip, the middle and the fundus. The results gave the best angle to fracture the odontoid process of the axis.

四、建立了枢椎的三维有限元模型，对枢椎齿状突骨折机理进行了理论上的研究，重点针对临床上齿突骨折的三种分类：1、齿突尖骨折；2、齿突腰部骨折；3、齿突基底部骨折，赋予齿状突在矢状面沿各种角度下受力条件，模拟衰椎前弓、襄椎横韧带以及CZ－3棘间韧带对枢椎造成的暴力破坏，确定了最可能引起齿状突暴力骨折的受力角度。

Similarly, a axis FEM model was constructed to simulate the axis fracture, emphasized on the odontoid process. Three kind of odontoid process fracture were analysed on this model, which occurred respectively on the tip, the middle and the fundus. The results gave the best angle to fracture the odontoid process of the axis.

四、建立了枢椎的三维有限元模型，对枢椎齿状突骨折机理进行了理论上的研究，重点针对临床上齿突骨折的三种分类：1、齿突尖骨折：2、齿突腰部骨折：3、齿突基底部骨折，赋予齿状突在矢状面沿各种角度下受力条件，模拟寰椎前弓、寰椎横韧带以及C2-3棘间韧带对枢椎造成的暴力破坏，确定了最可能引起齿状突暴力骨折的受力角度。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。