颈椎后路单开门椎管扩大椎板成形术后C5神经根麻痹的解剖学研究

Anatomical study on C5 nerve palsy after posterior cervical single-door laminoplasty

中文关键词:  颈椎后路单开门椎管扩大椎板成形术  C5神经根麻痹  解剖学机制  膜椎韧带  神经根损伤

英文关键词:Expansive open-door laminoplasty  C5 plasy  Anatomical mechanism  The meningovertebral ligaments  Nerve root lesion

中文摘要:

  【摘要】 目的：探讨颈椎后路单开门椎管扩大椎板成形术后C5神经根麻痹可能的解剖学机制。方法：取8具防腐正常成人颈部标本（年龄54~78岁，平均66.4±7.3岁）。仔细从后方剔除颈椎周围的软组织，暴露双侧椎板，在双侧关节突关节内侧各作一条沟，铰链侧保留内层骨板，开门侧完全穿透内层骨板。掀起开门侧椎板后，剔除脂肪组织，分离和保留椎管后方的所有韧带结构，在肉眼及手术显微镜下观察椎管后方的韧带的形态、走行、起始位置及分布特点，用游标卡尺在手术显微镜下测量韧带的长度、宽度及厚度。从不同节段观察硬膜囊及神经根在开门前后的改变。最后，测量C4~C8硬膜内腹侧支上端及下端的长度。结果：在8个颈椎标本的椎管后方共发现37条的膜椎韧带。膜椎韧带的一端附着于黄韧带或椎板内面，另一端与硬膜囊后壁相连，形状以条索型多见。韧带的长度为7.37~20.09mm（12.24±3.21mm），各节段自上往下呈逐渐增加的趋势；厚度最厚处达1.12mm。膜椎韧带在脊髓的C3-C4节段分布较多。在易发病的节段中，C5硬膜内腹侧支上端及下端的长度是最短的（13.18±1.12mm，8.07±1.11mm）。在颈椎后路单开门椎管扩大椎板成形术后，观察到椎管后方的膜椎韧带绷紧，硬膜囊变形，脊髓以及神经根发生移位。结论：膜椎韧带牵拉可能是C5神经根麻痹发生的重要因素。切断膜椎韧带可能有助于降低术后C5神经根麻痹的发生率。

英文摘要:

  【Abstract】 Objectives: To investigate the possible anatomical mechanism of C5 nerve palsy after cervical expansive single-door laminoplasty. Methods: Eight whole cervical embalmed cadavers (54 to 78 years, averaged 66.4±7.3 years) were studied. After dissecting postvertebral muscles, the bilateral laminae were exposed. A gutter was created above the inner cortex at the medial border of the facet joints as hinges, while another gutter on the contralateral side penetrated the inner cortex and the spinal canal as open side. After lifting the open side of the laminae, any tough ligamentous structures between the posterior dura sac and the ligamentumflavum or laminae were observed and identified after removing the adipose tissue. The quantity, morphology, origin, insertion and the spatial orientation of the meningovertebral ligaments at the C3-7 region were observed. The length, width, and thickness of the ligamentous structures were measured with a millimeter caliper(accurate to 0.01mm). Then, changes of the dura sac and roots were observed at different segments. In addition, the most cranial and caudal lengths of the C4-C8 ventral rootlets were measured. Results: A total of 37 meningovertebral ligaments were found in 8 cervical spine specimens, connecting the posterior wall of the dura sac to ligamentum flavum or laminae. Ligament length varied from 7.37-20.09mm(12.24±3.21mm); the thickest one is 1.12mm. The meningovertebral ligaments had a tendency to be abundant at C3-C4 of spinal cord. Besides, the most cranial and caudal lengths of C5 ventral rootlets (13.18±1.12mm, 8.07±1.11mm) were the shortest in the vulnerable segments when lifting up the open side of lamina, the meningovertebral ligaments became tight, and the shape of the dura sac was changed, therefore the displacement of spinal cord and nerve root was observed. Conclusions: The meningovertebral ligaments might play an important role in the occurrence of postoperative C5 nerve palsy. Release of the meningovertebral ligaments may be effective in reducing the incidence of postoperative C5 nerve palsy.