同种异体骨圈椎体融合术稳定颈椎的生物力学评价

Biomechanical Evaluation on Cervical spine stabilizing Effects of Cervical Interbody Spinal Fusion Using Allograft Fusion Cage

目的 评价同种异体皮质骨圈（ＡＦＣ）重建颈椎稳定性的即刻效果及自身强度。方法在８ 具新鲜成人颈椎标本上，模拟临床术式，对Ｃ４，５ 、Ｃ５，６ 行椎间盘切除术，分别将髂骨、ＡＦＣ 置于椎间隙，对节段进行压缩、植入物拔出测试（Ｃ４，５） 和脊柱三维运动稳定性评价（Ｃ５，６）。结果 （１）ＡＦＣ组的运动范围与正常组和髂骨组相比，除后伸运动范围略有增大外，其余方向的运动范围均减小。（２） 在压缩载荷为（５０２ ±１１４）Ｎ 时，ＡＦＣ组的椎骨有挤压破坏，而ＡＦＣ结构正常；在３００ Ｎ 的拔力作用下，骨圈与椎体间无松动。而在髂骨组中，当压力为（１３５ ±４２）Ｎ 时，植骨块被破坏；在６０ Ｎ 的拔力作用下，植骨块与椎体间产生松动移位。结论 ＡＦＣ 具有足够的支撑、抗滑、维持或增加椎间隙高度的功能，符合生物力学及临床要求。

Objective\ To evaluate the immediate effects and strength of allograft fusion cage(AFC) used for reconstructing stability of cervical spine. Methods\ Discs of C 5 and C 6 were resected on 8 fresh human cervical spine specimens, and autogenous iliac bone grafts(AIBG), and AFCs were implanted into the intervertebral spaces respectively. Compression test, pull out test and segmental motion measurement were studied.Results\ Comparing with intact and AIBG groups, the range of motions of C5-6 in AFC group were decreased in all directions except for extension; with (502±114) N compressive load,the vertebrae in AFC group were broken while the AFC were intact, but the AIBG were broken at (135±42) N load; with 300 N drawing load,no loosening was found between AFCs and vertebra, but it was found between AIBG and vertebra at 60 N load. Conclusion\ AFC could provide enough support,anti slide ability and could remain or increase the height of intervertebral spaces. It completely meets clinical and biomechanical requirements.