颈椎椎间孔组织对神经根固定作用的生物力学研究

The fixation of tissue in intervertebral foramen on cervical nerve roots

目的：从生物力学角度观察椎间孔组织对神经根的固定作用及其各根之间的差异。方法：采用６例新鲜颈椎标本，保留椎间孔组织，后路暴露神经根。椎间孔外牵神经干，传感器测量椎管内神经根张力。结果：神经根张力随加载外力的增加而增大，其中Ｃ８神经根变化最明显。外力在５００ｇ以内时，Ｃ５、Ｃ６、Ｃ７神经根张力上升缓慢，超过此值，上升明显。Ｃ５、Ｃ６、Ｃ７与Ｃ８神经根断裂时，外力相差１０００ｇ左右。结论：颈椎椎间孔对Ｃ５、Ｃ６、Ｃ７神经根存在明显固定作用，而Ｃ８神经根的固定作用相对较弱。

Objective:The fixation of tissue in the intervertebaral formen cervical on nerve roots and the difference in each root was observed by biomechanical study. Methods:The nerve root was explored by laminectomy in fresh cervical spines of adult cadavers. The tension of nerve root was measured when nerve trunk was stretched.Results:The tension of nerve roots was increased when the stretching force increased gradually,especially in C 8 nerve root. The tension of C 5,C 6 and C 7 nerve roots was rising obviously beyond 500g.The stretching force to make nerve root snap on C 5,C 6 and C 7 nerve root was 1000g greater than that on C 8 nerve root.Conclusions:The tissue around the nerve root within the intervertebral foramen can fix C 5,C 6 and C 7 nerve root stronger than C 8 nerve root.That could be the biomechanical cause of branchial plexus palsy with C 8 root avulsion.