颈椎不稳动物模型中椎动脉结构变化的观察

Chang of Vertebral Artery Structure in Animal Model of Cervical Instability

目的观察兔颈椎不稳动物模型中椎动脉的结构变化。方法 60只成年健康日本大耳白兔,随机分为两组,每组30只。实验组结扎并切断颈椎C4/5节段颈后肌群,然后切断C4/5节段的棘上及棘间韧带,同时行前路手术损伤C4/5前纵韧带和椎间盘结构;对照组仅切开显露并缝合颈部前后侧皮肤,切口长度与实验组相同,不做其他手术。于术后第1、2、3个月拍摄颈椎过伸过屈位X线片,并测量C4相对活动度;术后第3个月,处死全部动物并取椎动脉标本,应用计算机图像分析系统测量椎动脉外径、内径、管壁厚度。结果实验组兔C4相对活动度在术后第1、2个月和对照组比较无统计学意义(P>0.05);在术后第3个月显著高于对照组,有统计学意义(P<0.05)。两组椎动脉外径比较无统计学意义(P>0.05);两组椎动脉内径、壁厚比较有统计学意义(P<0.05)。结论破坏颈椎C4/5节段韧带和肌肉连接的方法可以成功制作颈椎不稳的动物模型,颈椎不稳时存在着椎动脉结构的异常。

Objective To observe the change of vertebral artery structure in the animal model of cervical instability.Methods Totally 60 adult healthy Japanese white rabbits were randomly divided into the experimental group（n=30） and the control group（n=30）.The experimental group were given transection of posterior muscles of neck and supraspinous and interspinous ligament at C4/5,and then were given destruction of anterior longitudinal ligament and intervertebral discs at C4/5 form anterior approach.The control group were given a sham operation.Cervical extension and flexion position X-ray was taken at 1,2,3 months after operation.Relative motion degree of C4 was measured.All animal were sacrificed at 3 months and the vertebral arteries were picked up for pathology examination.External diameter,internal diameter and wall thickness of the vertebral arteries were analysed with computer image analysis system.Results There was no signifcant difference in relative motion degree of C4 between two groups at 1,2 months after operation（P〉0.05）.There was signifcant difference in relative motion degree of C4 between two groups at 3 months after operation（P〈0.05）.There was no signifcant difference in external diameter of the vertebral arteries between two groups（P〉0.05）.There was signifcant difference in internal diameter and wall thickness of the vertebral arteries between two groups（P〈0.05）.Conclusion Cervical instability was induced by transection of muscles and ligament between C4/5.Accompany with cervical instability,the vertebral artery structure changed abnormally.