中文摘要：

目的 自行研制寰枢椎侧块关节融合器,评价其与寰枢椎椎弓根螺钉内固定联合应用的生物力学稳定性.方法 选取46套正常寰枢椎CT三维重建片,测量寰椎侧块关节面矢状径、横径,枢椎侧块关节面矢状径、横径,寰枢椎侧块关节间隙高度.以此为依据,设计寰枢椎侧块关节融合器.取6具新鲜尸体枕颈部（C0～C4）标本.测量1.5 N·m载荷下C1.2节段的三维运动范围.标本按随机顺序,依次测量完整状态、不稳状态（齿突周围韧带切除）及经寰枢关节螺钉＋Gallie钢丝、寰枢椎椎弓根螺钉、寰枢椎侧块关节融合器＋寰枢椎椎弓根螺钉（C1＋C2＋cage）固定后的三维运动范围.结果 寰枢椎侧块关节间隙高度为（3.04±0.46） mm.融合器的相应宽度/长度分别设计为8/11、9/12、10/13 mm,高度设计为3.5、4.0、4.5 mm.三种内固定方式的运动范围均小于完整状态和不稳状态,差异有统计学意义.C1＋C2＋cage内固定在三种内固定方式中侧屈、旋转方向的运动范围最小,在屈伸方向运动范围最大,但差异均无统计学意义.结论 C1＋C2＋cage内固定具有与目前常用的寰枢椎内固定方式相当的稳定性,并能够提供额外的寰枢椎植骨融合点,可作为寰椎后弓缺如患者寰枢椎融合方式的一种选择.

英文摘要：

Objective To design an atlantoaxial lateral mass fusion cage and evaluate its biomechanical stability when it is combined with atlantoaxial vertebral pedicle screw fixation.Methods Forty-six sets of CT 3D reconstruction pieces of the normal atlantoaxial junction were chosen to measure sagittal diameter and transverse diameter of atlantoaxial lateral mass joint,sagittal diameter and transverse diameter of epistropheus lateral mass and space height of atlantoaxial lateral mass joint.An atlantoaxial lateral mass fusion cage was designed on this basis.Six fresh human cadaveric cervical spines （C0-C4） were used as samples to measure 3D motion range of C1,and 2 segments under 1.5 N · m load.3D motion range of samples under the following situations was measured at random：intact state,unstable state （ligament around odontoid process was cut off）,fixation with atlantoaxial joint screw＋Gallie steel wire,atlantoaxial pedicle screw,atlantoaxial lateral mass joint fusion cage＋atlantoaxial vertebral pedicle screw.Results Corresponding width/length of fusion cage is 8/11,9/12,10/13 mm,respectively,and the height is designed to 3.5,4.0,and 4.5 mm,respectively.The motion range of three internal fixation methods is less than that under intact state and unstable state.The difference has statistical significance.The C1＋C2＋cage fixation produces the least motion range in lateral bending and axial rotation directions and generates the highest motion range in flexion/extension direction.But,the difference has no statistical significance.Conclusion The C1＋C2＋cage internal fixation technique has similar stability with common atlantoaxial intemal fixation method and can provide extra atlantoaxial fusion spots.Thus,it may be a feasible alternative for atlantoaxial fusion when the posterior arch of the atlas is absent.