钉棒系统在颈椎单开门椎管扩大成形术中的力学研究

Biomechanics study of rod-screw system in unilateral open-door cervical laminoplasty

目的评价钉棒系统固定侧块及椎板在颈椎单开门椎管扩大成形术中的力学稳定性。方法选用6例无损伤的人尸体颈椎标本（由南昌大学医学院解剖教研室提供）,每例选取C3~C7节段。经随机化处理分为3组,每组10个节段,所有节段进行单开门椎管扩大成形,根据固定方式分为螺钉丝线组（A组）、钛板组（B组）和钉棒系统组（C组）。应用南昌大学力学中心生物材料实验机对各颈椎节段进行生物力学性能测试,分别测量每组的拔出力、椎板再关门的最大负荷及完全关门负荷并进行分析。结果 A、B、C组的最大拔出力分别为（13.88±4.34）、（100.65±14.15）和（198.37±46.88）N,差异有统计学意义（P〈0.05）。3组在再关门负荷过程中最大负荷分别为（14.68±3.14）、（746.84±170.09）和（769.88±146.89）N;完全关门负荷分别为（14.68±3.14）、（746.84±170.09）和（769.88±146.89）N。B、C组与A组比较差异有统计学意义（P〈0.05）,B、C组比较差异无统计学意义（P〉0.05）。结论钉棒系统固定侧块及椎板在颈椎单开门扩大成形术中具有一定的力学优势。

【Objective】 To evaluate the stability of rod-screw system in unilateral open-door cervical laminoplasty. 【Methods】 The adult cadaver cervical spine specimens（C3-C7） of 6 cases were provided by the Department of Anatomy in the Medical College of Nanchang University. The unilateral open-door cervical laminoplasty was performed in all the specimens, then the specimens were randomly divided into 3 groups according to the pattern of fixation, i.e. group A of screw fixation, group B of titanium plate fixation and group C of rod-screw system fixation. The pullout strength, the maximal load and complete reclose load were evaluated in the Biomechanics Research Center of Nanchang University. At last, all the data were analyzed by SPSS 13.0. 【Results】In the groups A, B and C, the pullout strength was（13.88 ± 4.34） N,（100.65 ± 14.15） N and（198.37 ± 46.88） N respectively with significant differences among the three groups（P 〈 0.05）. The maximal load was（14.68 ± 3.14） N in the group A,（746.84 ± 170.09） N in the group B and（769.88 ± 146.89） N in the group C. The complete reclose load was（14.68 ± 3.14） N in the group A,（746.84 ± 170.09） N in the group B and（769.88 ± 146.89） N in the group C. There were significant differences between the group A and the groups B and C, but there was no significant difference between the group B and the group C. 【Conclusion】Fixation with rod-screw system in unilateral open-door cervical laminoplasty is more stable according to study of biomechanics.