颈椎间孔内口锚链韧带的形态和分布特征

目的 通过解剖学观察,揭示颈椎间孔内口区锚链韧带的形态及其分布特征,探讨其与神经根型颈椎病神经卡压之间的关系。 方法 12具成人脊柱颈段防腐标本,正中矢状切开,从脊神经根袖根部切断根袖,在外科显微镜下解剖观察C3/4～C7/T1椎间孔内口处神经根袖周围的锚链韧带,记录韧带的形态、分布、起止点及走行。 结果 120个椎间孔内口脊神经根袖周围共发现560条锚链韧带,所有韧带均呈放射状连于神经根袖与椎间孔内口周围骨膜壁,两端附着紧密,不易分离。各椎间孔内口韧带的数目均≥4个。锚链韧带形态主要包括带形和索形两种。带形韧带258条,宽度（4.5±2.6）mm（4.1~5.2 mm）,索形韧带302条,直径（2.5±1.8）mm（1.2~3.8 mm）。C3/4、C7/T1椎间孔内口区韧带较为松散纤细,数量较少;C4/5~C6/7椎间孔内韧带较为坚韧而粗壮,数量较多。 结论 颈椎椎间孔内口区神经根周围存在锚链韧带,将神经根锚定于周围椎间孔骨膜壁,极大限制了神经根自由移动范围,可能与突出椎间盘一起导致神经根卡压,是神经根型颈椎病的潜在解剖学因素。     

The sinuvertebral nerves at the craniovertebral junction: A microdissection study

Bogduk et al. ( 1988 , Spine 13:2–8) noted that the joints and ligaments at the cervico‐occipital region are susceptible to whiplash injury. The upper three cervical sinuvertebral nerves (SVNs) at the craniovertebral junction (CVJ) are thought to be responsible for mediating pain from the ligaments, dura mater, and soft tissues of the posterior cranial fossa and upper cervical column. The purpose of this study was to describe in detail the origin and course of the SVNs at C0–C1, C1–C2, and C2–C3 intervertebral levels and their anterior intraspinal distribution. A sample comprising 10 adult, 12 fetal (crown rump length = 155–250 mm), and three stillborn neonatal (n = 50 sides) embalmed cadaveric cervical spines was microdissected (Carl Zeiss, Jena, Germany, 8–40× magnification). A laminectomy of the cervical spine with an occipital craniectomy (seven adult and all fetal specimens) or a horizontal section of the intervertebral levels was performed (three adult specimens) to expose the craniocervical canal. In both adult and fetal specimens, all three cervical SVNs arose from two roots, a somatic root (from the spinal nerve or ventral ramus or both) and a sympathetic root (from the vertebral artery plexus or superior cervical ganglion). The C1 and C2 SVNs were variable in number. The C2 and C3 SVN innervated most of the structures at the CVJ as well as the basiocciput region. The C1 SVN supplied a very small part of the atlanto‐occipital joint area. The intraspinal courses of all three SVNs consisted of ascending and descending branches closely adherent to the arteries of the CVJ. They supplied the dura mater, the ligaments, adjacent joints, and soft tissues by tiny branches from the main branches. The detailed origins and course are described. Clin. Anat. 2013. © 2012 Wiley Periodicals, Inc.     

多间隙微创前路椎间孔减压术对颈椎稳定性的影响

背景临床上颈椎钩突关节增生经常是多节段存在,由于多间隙病变复杂,手术方案的制定需要考虑多种因素。临床医生发现,即使是采用微创前路椎间孔减压术治疗两节段的神经根型颈椎病,减压充分后也不一定都需要行椎间融合术。目的本文对两个节段的钩突进行部分切除后,研究对颈椎稳定性的影响。方法依据健康志愿者的影像学资料,采用Mimics13.1、Solid Works2012软件建立三维几何模型,ANSYS15.0软件进行网格划分和网格优化,赋值各类组织的材料属性,建立颈椎(C2-C7)三维有限元模型,通过有限元分析技术研究部分切除单侧两个钩突后对颈椎稳定性和邻近节段椎体应力的影响。结果采用文中所述切除方法进行左侧钩突部分切除后,当切除双节段(60+60模型)时,各个工况下的最大位移相对于前3种切除方式均有明显的增大,而且各个工况下的最大应力相对于前3种切除方式均有显著增大。结论随着切除节段的增多和切除范围的增大,节段之间的活动度增大,局部应力增大,给颈椎带来一定的影响,导致颈椎不稳,加速颈椎的退变。因此在制定手术方案时,要严格掌握手术适应证,除非有明确的神经根、脊髓受压的指征,否则不可盲目扩大切除范围。     

颈椎椎间孔外口区韧带的解剖学观测

目的　对颈椎C_2~7椎间孔外口区域的韧带进行解剖学描述并探讨其临床意义。 方法　对10具成人尸体标本的 100个椎间孔进行解剖观测。鉴别所有出现的韧带,观察并记录C2~7椎间孔外口区域椎间孔外韧带的数量、形态、分布和起止位置。并用游标卡尺分别测量每条韧带的长度、宽度和厚度。 结果　在100个椎间孔外口区域共发现252个椎间孔外韧带。椎间孔外韧带可以分为放射型韧带236 个(93.7 %)和横跨型韧带16个(6.3 %)两种。放射型韧带将神经根连接到周围结构,可分为上方韧带（25.0%）,下方韧带（60.2%）,前方韧带（6.3%）和后方韧带（8.5%）;横跨型韧带与神经根相垂直并横跨于神经根上,其中,横跨型韧带在C4~5节段最为常见,在C4~5节段的平均长度为横跨型韧带长度为(8.12±1.38) mm(6.28~9.93 mm),厚度最厚可达1.04 mm,每个颈椎椎间孔最多只有一条横跨型韧带。 结论　椎间孔外韧带是椎间孔正常的生理结构,可能与颈椎减压术后C5神经麻痹的发生有关。在颈椎减压术后,横跨型韧带可能是造成神经根卡压而引起神经损伤的潜在原因之一。而放射型韧带可以限制脊神经移位,可能因此牵拉神经引起损伤。     

Details of fibroligamentous structures in the cervical unco-vertebral region: an obscure corner

Vertebral bone, joints and ligaments on the cervical spine are structures that maintain the stability of the spine and protect the neurovascular structures. Determining the detailed anatomical location of the intervertebral foramen and unco-vertebral (UV) region with respect to the vertebral bone, joint and ligaments is critical when choosing the safest surgical approach to the cervical spine. We studied the microscopic detailed anatomy of the dural covering and posterior longitudinal ligament (PLL) in eight cadaver specimens and the relevance of these structures in the UV region from C4 to C7. The uncinate process (UP) and its covering ligaments are mechanical barriers that prevent the nerve root and the vertebral artery against unintentional surgical damage. Dissection at the posterolateral surface of the UP revealed a separate perivascular fibroligamentous tissue (PVFLT) that originates from the PLL. The recognition of the PVFLT may provide for safe surgery by protecting the neural and vascular structures during decompression in the UV region.     

首例中国数字化可视人体脊柱区颈段的三维重建研究

目的 建立中国数字化可视人体男性脊柱区颈段的三维可视化模型。方法 应用首例中国数字化可视人体数据集，选取从寰椎上缘到第7颈椎下缘的连续横断面图像。在SGI工作站上对颈椎、脊髓、椎动脉、椎间盘、颈神经等结构进行计算机三维重建并立体显示。结果 建立了脊柱区颈段重要结构的三维可视化模型，重建后的结构可多彩色立体显示，既能单独显示，也能任意搭配或总体显示，可在三维空间位置上绕任意轴旋转任意角度观察。结论 脊柱区颈段的可视化数字模型，用三维图形方法显示该区结构的空间构形，将有助于解剖学教学，并可为颈部疾病的影像诊断和外科手术等提供参考。     

颈椎椎间孔组织对神经根固定作用的生物力学研究

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。这可能是Ｃ８神经根节前损伤较为多见的生物力学原因     

Intradural anastomoses between the accessory nerve and the posterior roots of cervical nerves: their clinical significance.

This study was performed to identify the anastomoses between the accessory nerve and the posterior roots of cervical nerves below the level of C1 segment, and to evaluate their clinical significance. One hundred spinal cord sides of Koreans were studied under the surgical microscope. In order to trace the posterior root of a cervical nerve after anastomosis with the accessory nerve, or the bridging fibers between the accessory nerve and the cervical posterior roots, the accessory nerves with the posterior roots and the bridging fibers were stained with osmium tetroxide. The anastomosis was classified into five types, according to whether the accessory nerve and the cervical posterior root crossed each other, and also according to the site of the bridging fiber between them. The bridging fibers in the most common type of anastomoses were observed to connect the posterior roots of a cervical nerve with the spinal rootlet of the accessory nerve. The possibility that the motor fibers of accessory nerve from the spinal cord may innervate the trapezius muscle through the cervical nerve, was discussed.     

High-resolution human cervical spinal cord imaging at 7 T

We present high‐resolution anatomical imaging of the cervical spinal cord in healthy volunteers at the ultrahigh field of 7 T with a prototype four‐channel radiofrequency coil array, in comparison with 3‐T imaging of the same subjects. Signal‐to‐noise ratios at both field strengths were estimated using the rigorous Kellman method. Spinal cord cross‐sectional area measurements were performed, including whole‐cord measurements at both fields and gray matter segmentation at 7 T. The 7‐T array coil showed reduced sagittal coverage, comparable axial coverage and the expected significantly higher signal‐to‐noise ratio compared with equivalent 3‐T protocols. In the cervical spinal cord, the signal‐to‐noise ratio was found by the Kellman method to be higher by a factor of 3.5 with the 7‐T coil than with standard 3‐T coils. Cervical spine imaging in healthy volunteers at 7 T revealed not only detailed white/gray matter differentiation, but also structures not visualized at lower fields, such as denticulate ligaments, nerve roots and rostral–caudal blood vessels. Whole‐cord cross‐sectional area measurements showed good agreement at both field strengths. The measurable gray/white matter cross‐sectional areas at 7 T were found to be comparable with reports from histology. These pilot data demonstrate the use of higher signal‐to‐noise ratios at the ultrahigh field of 7 T for significant improvement in anatomical resolution of the cervical spinal cord, allowing the visualization of structures not seen at lower field strength, particularly for axial imaging. Copyright © 2011 John Wiley & Sons, Ltd.     

The relationship between disc degeneration and morphologic changes in the intervertebral foramen of the cervical spine: a cadaveric MRI and CT study

A cadaveric study was performed to investigate the relationship between disc degeneration and morphological changes in the intervertebral foramen of cervical spine, including the effect on the nerve root. Seven fresh frozen human cadavers were dissected from C1 to T1, preserving the ligaments, capsules, intervertebral disc and the neural structures. The specimens were scanned with MRI and then scanned through CT scan in the upright position. Direct mid-sagittal and 45 degree oblique images were obtained to measure the dimension of the intervertebral disc height, foraminal height, width, area and segmental angles. Disc degeneration was inversely correlated with disc height. There was a significant correlation between disc degeneration and foraminal width (p<0.005) and foraminal area (p< 0.05), but not with foraminal height. Disc height was correlated with foraminal width but not with height. The segmental angles were decreased more in advanced degenerated discs. There was a correlation between nerve root compression and decreased foraminal width and area (p<0.005). This information and critical dimensions of the intervertebral foramen for nerve root compression should help in the diagnosis of foraminal stenosis of the cervical spine in patients presenting with cervical spondylosis and radiculopathy.     

颈神经根槽和颈椎间孔的应用解剖

目的：为颈椎病的病因、诊断和治疗提供补充的定量数据。方法：在干燥的颈椎椎骨标本和福尔马林固定的颈椎标本上，测量颈神经根槽和颈椎椎间孔。结果：内侧区的平均长度，内侧区前缘中点到椎体中线的距离从C3～C7逐渐增加。C3内侧区的宽度较大，C7上、下关节突及峡部高度之和的后中点到颈神经根槽后壁的前后距离最小。结论：研究结果为影像诊断和外科手术提供了相关的应用解剖数据。     

Clinical importance of ligamentous and osseous structures in the cervical uncovertebral foraminal region

The vertebral artery, cervical spinal nerves, spinal nerve roots, and the bony and ligamentous tissue related to the cervical vertebrae are structures whose anatomy determines the path of a surgical approach. Defining the anatomy and, in particular, determining the precise location of vulnerable structures at the intervertebral foramen and the uncovertebral foraminal region (UVFR), a region defined by the uncinate process anteriorly, the facet joint posteriorly and the foramen transversarium laterally, has critical significance when selecting the safest surgical approach. We studied the anatomy of the vertebral artery, cervical spinal nerves, and spinal nerve roots within the UVFR in six cadaver specimens. We also obtained measurements of bony structures in 35 dry cervical vertebral columns, from C3-C7. The uncinate process (UP) projects superiorly from the posterolateral aspect of each cervical vertebral body, except for the first and second vertebrae. Because the posterior part of the UP lies adjacent to the vertebral artery, spinal nerve, and spinal nerve roots, its resection creates sufficient space to decompress these structures directly. The posterolateral surface of the UP is covered by ligamentous tissue that originates from the posterior longitudinal ligament and protects the neural and vascular structures during their decompression in the UVFR.     

Three-dimensional kinematic stress magnetic resonance image analysis shows promise for detecting altered anatomical relationships of tissues in the cervical spine associated with painful radiculopathy

For some patients with radiculopathy a source of nerve root compression cannot be identified despite positive electromyography (EMG) evidence. This discrepancy hampers the effective clinical management for these individuals. Although it has been well-established that tissues in the cervical spine move in a three-dimensional (3D) manner, the 3D motions of the neural elements and their relationship to the bones surrounding them are largely unknown even for asymptomatic normal subjects. We hypothesize that abnormal mechanical loading of cervical nerve roots during pain-provoking head positioning may be responsible for radicular pain in those cases in which there is no evidence of nerve root compression on conventional cervical magnetic resonance imaging (MRI) with the neck in the neutral position. This biomechanical imaging proof-of-concept study focused on quantitatively defining the architectural relationships between the neural and bony structures in the cervical spine using measurements derived from 3D MR images acquired in neutral and pain-provoking neck positions for subjects: (1) with radicular symptoms and evidence of root compression by conventional MRI and positive EMG, (2) with radicular symptoms and no evidence of root compression by MRI but positive EMG, and (3) asymptomatic age-matched controls. Function and pain scores were measured, along with neck range of motion, for all subjects. MR imaging was performed in both a neutral position and a pain-provoking position. Anatomical architectural data derived from analysis of the 3D MR images were compared between symptomatic and asymptomatic groups, and the symptomatic groups with and without imaging evidence of root compression. Several differences in the architectural relationships between the bone and neural tissues were identified between the asymptomatic and symptomatic groups. In addition, changes in architectural relationships were also detected between the symptomatic groups with and without imaging evidence of nerve root compression. As demonstrated in the data and a case study the 3D stress MR imaging approach provides utility to identify biomechanical relationships between hard and soft tissues that are otherwise undetected by standard clinical imaging methods. This technique offers a promising approach to detect the source of radiculopathy to inform clinical management for this pathology.     

Anatomic basis of the anterior surgery on the cervical spine: relationships between uncus-artery-root complex and vertebral artery injury

Vertebral artery injury is a serious complication during anterior surgery on the cervical spine. However, little information is available in the literature concerning the mechanism of vertebral artery laceration during the procedures of the anterior cervical decompression. In the current study twenty-eight cadavers were dissected to determine the location and relationships of the fibro-ligamentous tissues to the uncinate process, vertebral artery and nerve roots from the C3 to C6 levels. The vertebral artery and nerve root are encased by a fibro-ligamentous band at the level of the intertransverse space. This fibro-ligamentous band is attached to the lateral aspect of the uncinate process and uncovertebral joint, which combines the vertebral artery, nerve root and uncinate process to form a complex or unit. The fibro-ligamentous tissues between the uncovertebral joint and vertebral artery may explain the propensity to vertebral artery laceration during resection of the uncinate process or an osteophyte projecting from the uncovertebral joint. For this reason, the authors recommend that before resection of the uncinate process or uncovertebral joint is performed, it is necessary to thoroughly dissect the fibro-ligamentous tissues off the uncinate process.     

Microsurgical anatomy of the denticulate ligaments and their relationship with the axilla of the spinal nerve roots

The denticulate ligaments (DL), 20 or 21 pairs of meningeal extensions, spread from the lateral aspect of the spinal cord to the internal aspect of the spinal dura mater. The aim of this study is to define the specific relationship of the DL with adjacent axilla of the spinal nerve roots and to investigate the anatomical features of the DLs and their variations. The topographical anatomy of the DLs and their relationships with the adjacent axilla of the spinal nerve roots was examined on 16 formalin‐fixed adult cadaveric spinal cords. The distances from the dural attachment of the DL to the axilla of the superior and inferior spinal nerve roots were measured bilaterally at every spinal level. Also the distances from the dural attachment of the DL to the lateral aspect of the spinal cord were measured bilaterally. Cervical DLs showed a triangular shape, while in the thoracic segment the ligament changes the shape to “Y.” Also the most caudal DL was identified to be at the L1–2 level. Our study revealed that the distances from the dural attachment of the DL to the superior and inferior spinal nerve root axilla were different at the cervical, upper thoracic and the lower thoracic segments. Both distances to the superior and inferior spinal nerve root axilla were shown to increase from cervical to lower thoracic segments. This study provides a detailed anatomy of the DLs and their relationship with the adjacent spinal nerve root axilla. Clin. Anat. 27:733–737, 2014. © 2013 Wiley Periodicals, Inc.     

Microanatomical considerations for safe uncinate removal during anterior cervical discectomy and fusion: 10-year experience

Cervical radiculopathy from uncovertebral joint (UVJ) hypertrophy and nerve root compression often occurs anterior and lateral within the cervical intervertebral foramen, presenting a challenge for complete decompression through anterior cervical approaches owing to the intimate association with the vertebral artery and associated venous plexus. Complete uncinatectomy during anterior cervical discectomy and fusion (ACDF) is a controversial topic, many surgeons relying on indirect nerve root decompression from restoration of disc space height. However, in cases of severe UVJ hypertrophy, indirect decompression does not adequately address the underlying pathophysiology of anterolateral foraminal stenosis. Previous reports in the literature have described techniques involving extensive dissection of the cervical transverse process and lateral uncinate process (UP) in order to identify the vertebral artery for safe removal of the UP. Recent anatomical investigations have detailed the microanatomical organization of the fibroligamentous complex surrounding the UP and neurovascular structures. The use of the natural planes formed from the encapsulation of these connective tissue layers provides a safe passage for lateral UP dissection during anterior cervical approaches. This can be performed from within the disc space during ACDF to avoid extensive lateral dissection. In this article, we present our 10-year experience using an anatomy-based microsurgical technique for safe and complete removal of the UP during ACDF for cervical radiculopathy caused by UVJ hypertrophy.     

颈椎术后轴性症状与影像学评价指标相关性的研究进展

目前,临床上将颈椎术后颈项及肩背部疼痛、僵硬、肌肉紧张酸胀及活动受限等不适感称为轴性症状（AS）。颈椎术后轴性症状的评价及影响因素尚无统一标准,既往众多影响因素中研究较多的是颈椎手术方式,而颈椎影像学参数评价指标与术后轴性症状的相关性是近年来脊柱外科医生研究的热点问题。颈椎手术方式的选择以及大部分颈椎影像学评价指标的改变所引起的术后轴性症状或许均与颈后肌肉、韧带等软组织结构的力学环境和运动模式改变相关。颈后肌肉、韧带等软组织与颈椎影像学评价指标之间存在相互关联,若要进一步分析术后轴性症状的相关因素,则需相互结合,从整体考虑。     

Lumbar intrathecal ligaments

A meticulous examination was performed on 56 vertebral columns from cadavers between 64 and 89 years of age. Identification of all contents within the dural sac was completed; however, the main focus was the cauda equina and lumbar region. In addition to scope dissection, radiographs and histological preparations were used to identify structures, tissue types, and any possible pathology. Discrete intrathecal ligamentous bands were observed in all cadavers examined. They were found randomly binding the dorsal nerve roots of the cauda equina to the dura. Occasional binding of the ventral nerve roots to the dorsal roots was observed. Histological examination demonstrated a dense collagen ligament varying between 0.13 and 0.35 microm in thickness and from 3 mm to 3.5 cm in length. The average number of ligaments found per cadaver was 18. These ligaments displayed a broad base attachment to the nerve root or dura of approximately 3 mm. Looping of the nerve roots associated with these ligaments was seen in one cadaver with a burst fracture. Electron microscopic studies of these ligaments demonstrated similarities to denticulate ligaments. It is suggested that the intrathecal ligaments represent remnants from fetal development of the denticulate ligaments.     

A three-dimensional finite element model of the cervical spine: an investigation of whiplash injury

Very few finite element models of the cervical spine have been developed to investigate internal stress on the soft tissues under whiplash loading situation. In the present work, an approach was used to generate a finite element model of the head (C0), the vertebrae (C1–T1) and their soft tissues. The global acceleration and displacement, the neck injury criterion (NIC), segmental angulations and stress of soft tissues from the model were investigated and compared with published data under whiplash loading. The calculated acceleration and displacement agreed well with the volunteer experimental data. The peak NIC was lower than the proposed threshold. The cervical S- and C-shaped curves were predicted based on the rotational angles. The highest segmental angle and maximum stress of discs mainly occurred at C7–T1. Greater stress was located in the anterior and posterior regions of the discs. For the ligaments, peak stress was at anterior longitudinal ligaments. Each level of soft tissues experienced the greatest stress at the time of cervical S- and C-shaped curves. The cervical spine was likely at risk of hyperextension injuries during whiplash loading. The model included more anatomical details compared to previous studies and provided an understanding of whiplash injuries.     

Transforaminal ligament may play a role in lumbar nerve root compression of foraminal stenosis

Lumbar foraminal stenosis is a common pathological change, and lumbar nerve root compression in stenotic foramina was recently considered as one of the main causes of low back pain and leg pain. However, the exact mechanism of lumbar nerve root compression in foramina is still not clear. Previous studies indicated that loss of the intervertebral disc height could reduce the cross-sectional area of lumbar foramina, while lumbar nerve root compression by boundaries of foramina has not been observed in experimental reduction of the intervertebral disc height. Given the close anatomic relationship between transforaminal ligaments and lumbar nerve roots, we hypothesize that transforaminal ligament can be the leading cause of lumbar nerve root compression in foraminal stenosis. We also propose that there are two possible mechanisms of lumbar nerve root compression by transforaminal ligaments: (1) nerve roots are compressed by the transforaminal ligament which moves downward with the loss of the intervertebral disc height; (2) pathological transforaminal ligaments increase the risk of nerve root compression in foramina.