下颈椎前路内固定联合后路经关节金属螺钉置入固定的生物力学稳定性

背景：对退变性颈椎管狭窄单纯采用前路椎体次全切除或椎间盘切除或单纯后路单开门椎管扩大成行均不能彻底完成脊髓减压和脊柱三柱稳定。 目的：探讨下颈椎前路固定联合后路经关节螺钉固定的生物力学稳定性。  方法：正常成人尸体颈椎标本,每具分别制作以下两种模型：①经后路C3~C7单开门和下颈椎前路C5椎体次全切除钛网支撑植骨、ORION内固定模型(对照组)。②经后路C3~C7单开门和经关节螺钉内固定及下颈椎前路C5椎体次全切除钛网内植骨、ORION内固定模型(实验组)。 结果与结论：实验组在前屈、后伸、左、右侧屈及左、右旋转移位角度均小于对照组(P < 0.001)。提示：①在生物力学实验中,下颈椎前路固定联合后路经关突节螺钉固定的生物力学性能优良,对抗前屈、后伸、左、右旋转的作用力更强,颈椎可获得更可靠的稳定性。②下颈椎前路固定联合后路经关节螺钉固定在对抗颈椎前屈运动时力学稳定性更为强大。

Biomechanical stability of the lower cervical spine inter-fixation by anterior approach combined with posterior articular screws

BACKGROUND:A simple anterior corpectomy or discectomy, or simple posterior open canal to expand a single trip cannot fully complete three-column spinal cord decompression and spinal stabilization in patients with degenerative cervical stenosis. OBJECTIVE:To study the biomechanical stability of the lower cervical spine inter-fixation by anterior approach combined with posterior srticular screws.  METHODS:Ten cervical spine specimens were gained from cadavers. Every specimen was managed via two methods sequentially: The first method was by posterior C3-C7 open-door laminoplasty combined with posterior articular screw fixation and by anterior C5 subtotal corpectomy with bone granule graft in the titanium mesh and ORION fixation (test group); The second method was by posterior C3-C7 open-door laminoplasty and by anterior C5 subtotal corpectomy with bone granule graft in the titanium mesh and ORION fixation (control group). RESULTS AND CONCLUSION:Compared with the control group, displacement angles of flexion, extension, left/right lateroflexion left/right rotation in the test group were lower (P < 0.001). The findings indicated that: ①The lower spine gained the excellent biomechanical stability in flexion, extension, lateroflexion and rotation via the treatment of anterior fixation combined posterior articular screw fixation. ②The treatment of anterior fixation combined with posterior articular screw fixation provided significant biomechanical stability to the lower cervical spine in flexion position.