模拟肿瘤对颈胸段脊柱不同部位破坏后的生物力学研究

Biomechanical evaluation on the cervicothoracic spine stability after destruction induced by simulated osteolytic tumor at different sites of cervicothoracic vertebrae

目的:评价颈胸段脊柱T1在模拟溶骨性肿瘤不同部位(肋椎关节、椎弓根和关节突)的破坏情况下的生物力学特性,从而为采取预防性稳定手术提供理论依据,减少脊柱不稳发生神经损害的可能性,指导临床工作。方法:取6具新鲜冷藏人体尸体脊柱标本(C7-T2),测量胸椎在不同部位损伤后对脊柱稳定性的影响。按照不同的破坏部位分别为正常标本组(IS),椎体破坏(30%椎体面积破坏,下同)+椎体后壁破坏(VB+PW),椎体破坏+肋椎关节破坏(VB+CVJ),椎体破坏+椎弓根破坏(VB+P),椎体+肋椎关节+椎弓根破坏(VB+CVJ+P),椎体+肋椎关节+椎弓根+关节突破坏(VB+CVJ+P+FJ)。结果:椎体按照不同的部位破坏后,其屈服载荷按照完整标本、VB+PW、VB+CVJ、VB+P、VB+CVJ+P和VB+CVJ+P+FJ依次分别为(3549±254)、(3043±204)、(2680±164)、(2440±146)、(2168±110)和(1734±74)N,依次比正常标本下降了14·2%、24·5%、32·8%、40·0%和52·8%。结论:椎体和椎弓根同时破坏比单纯椎体破坏更加不稳,此时如有关节突关节破坏,后方承受载荷的结构如关节突关节将不能从后方支持椎体,发生椎体塌陷的危险性更高,可考虑采取预防性稳定手术。

Objective：To evaluate the biomechanical alteration after the destruction induced by simulated osteolytic tumor at different sites of cervicothoraeic vertebrae, including costovertebral joints, pedicles and facet joints, so as to provide the evidence to support the decision of operations for prophylactic stabilization, Methods：Six specimens obtained from human cervicothoracic spine were used, Each specimen consisted of three vertebrae（C7 - T2）with intervertebral discs and ribs. To evaluate the effect of tuner at different locations on the spinal stability, metastatic involvement were simulated as follows： intact specimen （IS）, vertebral body defect （30% ） ＋ posterior wall violation（VB ＋ PW）, vertebral body defect ＋ costovertebral joints violation（VB ＋ CVJ）, vertebral body ＋ pediele violation（VB ＋ P）, vertebral body ＋ eostovertebral joints ＋ pedide violation（VB ＋ CVJ ＋ P）, vertebral body ＋ costovertebral joints ＋ pediele ＋ facet joints violation（VB ＋ CVJ ＋ P ＋ FJ）. Results： It was demonstrated that the failure loads of the intact specimen（IS） ,VB ＋ PW, VB ＋ CVJ, VB ＋ P, VB ＋ CVJ ＋ P and VB ＋ CVJ ＋ P ＋ H were （3 549 ± 254）, （3 043 ± 204）, （2 680 ± 164）, （2 440 ± 146）, （2 168 ± 110） and （1 734 ± 74） N, respcetively. Conclusion：The destructions of both vertebral body and pedicles will be more unstable than the de struction of vertebral body merely. When the destructions of vertebral body, pedicles and facets joints simultaneously happened, the vertebra would potentially be more unstable and easier to collapse, therefore the surgical prophylactic stabilization should be operated.