目的　评价在颈椎单开门椎管扩大成形术中使用OsteoMed M3钉板内固定重建颈椎稳定性的效果。  方法　在6具颈椎标本上，分别行后路单开门丝线结扎及OsteoMed M3钉板内固定，在脊柱三维运动试验机上行颈椎前屈后伸疲劳运动试验，观察有无丝线断裂或平板螺钉脱出、断裂现象，如有则停止试验并记录发生时的周期。  结果    丝线结扎组的试验显示所有标本均出现部分缝合的关节囊韧带撕裂、门轴侧易活动，甚至关节囊撕裂、丝线脱落及再关门；而在 OsteoMed M3钉板内固定组不损伤关节囊，试验显示未出现钢板螺钉松动、断裂，未出现再关门现象。  结论　在颈椎单开门椎管扩大成形术中应用OsteoMed M3钉板内固定具有良好的生物力学性能，能重建颈椎稳定性,可满足颈椎后路手术的要求。

Objective　 To evaluate the effects of OsteoMed M3 titanium plate and screws on the initial stability of cervical vertebrae after expansive unilateral open-door laminoplasty.　Methods　OsteoMed M3 plate and screws and silk ligation were used for an simulated expansive unilateral open-door laminoplasty in six fresh human cervical spine specimens respectively，and fatigue experiment were measured in positions of flexion and extension on three-dimension motional stability test. The cessation of testing would be and the incidence of thread rupture and of loosening of thread and plate and screws were recorded.　Results　Partial rupture of joint capsule and easy move of the hinge side were seen in all of the specimens in the silk ligation. It were easily seen that rupture of joint capsule and cast of silk thread and reclose of the opened laminate as clinical widely used device for suture of joint capsule. There was no trauma on joint capsule in the OsteoMed M3 plate and screws, and no plate and screw loosening and rupturing and no reclose of the opened laminate. Conclusions　Unilateral open-door laminoplasty using OsteoMed M3 titanium plate and screws fixation is good for posterior cervical surgery because of its biomechanical advantage of maintaining signi?cant stabilization of the spine.