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

Summary 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.

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Considérations anatomiques sur les rapports du complexe uncus/artère/racine dans le cadre des lésions de l'artère vertébrale au cours de la chirurgie antérieure de la colonne cervicale

Résumé La blessure de l'artère vertébrale est une complication sérieuse au cours de la chirurgie antérieure de la colonne cervicale. Néanmoins, peu d'informations sont disponibles dans la littérature concernant les mécanismes de lacération de l'artère vertébrale au cours des gestes de décompression cervicale antérieure. Dans ce travail, 28 cadavres ont été étudiés pour déterminer la localisation et les relations du tissu fibro-ligamentaire en rapport avec l'uncus, l'artère vertébrale et les racines de C3 à C6. L'artère vertébrale et la racine sont entourées par des bandes de tissu fibro-ligamentaire au niveau de l'espace intertransversaire. Ces structures fibro-ligamentaires sont amarrées à la face latérale de l'uncus et de l'articulation uncovertébrale et réunissent l'artère vertébrale, la racine et l'uncus pour former une entité bien particulière. Ces structures fibro-ligamentaires entre l'articulation uncovertébrale et l'artère vertébrale peuvent expliquer les risques de lacération de l'artère vertébrale au cours de la résection de l'uncus ou des ostéophytes se projetant au niveau de l'articulation uncovertébrale. Pour cette raison les auteurs recommandent que, préalablement à la résection de l'uncus ou de l'articulation uncovertébrale, il soit pratiqué une dissection soigneuse de ces structures fibro-ligamentaires.

     

颈椎病前路手术减压范围标志的解剖学研究

目的:探讨颈前路手术减压范围及安全界限的解剖标志.方法:对12具成人尸体标本进行三维CT重建,并测量定位椎动脉所需解剖数据,在显微镜下测量颈长肌内侧缘间距等数据,并观察椎动脉、神经根、钩椎关节及其对应关系.结果:椎体前缘与横突孔前缘水平切线间距离、双侧横突孔内侧壁距离及颈长肌内侧缘间距由下端至上端逐渐减小;钩突前脚间距平均值约为(17.3±2.92)mm,硬膜囊平均宽度(16.5±0.42)mm;颈长肌内侧缘与椎动脉间距及颈长肌内侧缘至正中矢状面距离左右两侧测最值在C2,C7差别有显著性(P<0.05).在年老标本中均可发现不同程度的钩椎关节增生,主要以前部横向增生为主,最严重者完全遮蔽椎动脉且将其向后外侧挤压,且可压迫钩椎关节后外侧走行的神经根.结论:颈前路手术应做好充分术前准备,制定个体化手术方案,参考颈长肌及钩椎关节定位,尤其应重视钩椎关节增生的影响.     

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.     

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.     

计算机辅助导航技术在颈椎病模型前路手术的骨减压效果评估

目的:探讨导航技术用于指导颈椎病模型前路手术减压范围术中判定的可行性和防止椎动脉损伤的操作方法。方法:制备颈椎病的尸体骨赘模型12具,随机分为导航手术组和常规手术组,分别在计算机导航下和常规下进行颈椎前路减压手术,术前术后进行标本的三维CT扫描及重建。CT图像上测量数据,对两组数据进行比较和统计学分析。结果:(1)术前模型骨赘测量数据,两组无明显的差异。(2)椎体后缘骨赘切除比较,两组椎管矢状径恢复率和椎管面积恢复率有明显差异,椎体后缘手术范围偏差有显著差异;钩椎增生骨赘切除比较,两组神经根管面积恢复率和钩椎骨赘水平面切除率有显著差异;钩突切除效果比较,两组钩突切除边界的外缘至横突孔内缘的距离有显著差异。导航组骨减压效果优于常规组。结论:计算机辅助导航技术能够有效指导颈椎病模型前路骨减压范围,并防止椎动脉损伤,与常规手术相比导航手术操作范围更加准确、手术切除更加彻底,有很好的安全性。     

颈前路钩椎关节切除术的应用解剖

目的为临床颈前路钩椎关节切除手术提供应用解剖学基础。方法15套干燥成人颈椎标本,分别测定:①C3-C6横突孔的横、矢径;②钩椎关节与横突孔的间距;③横突孔前壁厚度;④钩椎关节与椎间孔的间距;⑤两侧椎间孔所在平面间夹角。14具成人尸体标本,解剖测定:①C3-C6各节段上下缘椎体正中线与椎动脉的距离;②各横突孔壁内和相邻横突孔间的椎动脉的长度;③椎间孔的横、竖径。结果①C3-C6中,C5的横突孔横径最小;②横突孔前壁厚度由C3-C6逐渐增加;③钩椎关节与横突孔间距在C6处最小;④椎体正中线与椎动脉V2段的距离由C3-C6逐渐增大。结论熟悉局部解剖是避免损伤椎动脉的关键     

颈椎前路减压手术解剖标志定位测量及其临床意义

目的　为颈椎前路减压手术在有限显露术野中达到安全、有效减压提供更科学的减压标志。 方法　在15具成人尸体标本上,解剖观测C3~7节段相关解剖数据,以所测量的数据为基础,计算：(1)椎体钩前脚至颈长肌内侧缘的距离/颈长肌内侧缘至正中矢状面的距离(AULD/MLPD); (2)椎体钩前脚至横突孔内侧缘的距离/椎体钩前脚至颈长肌内侧缘的距离(AUTD/AULD); (3)椎体钩前脚至硬膜囊外侧缘的垂直距离/椎体钩后脚至硬膜囊外侧缘的距离(AUDD/PUDD)和(4)椎体钩与神经根最近点和椎体钩前脚的垂直距离/椎体钩前后脚的垂直距离(UNAD/APUD)。 结果　AULD/MLPD在C3的平均值为0.83,在C4的平均值为0.55,在C5的平均值为0.20,在C6的平均值为0.34,在C7的平均值为0.27;AUTD/AULD的平均值为2.71;AUDD/PUDD的平均值为0.28;UNAD/APUD的平均值为0.34。 结论　椎体钩前脚是颈椎体前部恒定的解剖标志,可作为颈椎前路手术的稳定、可靠的骨性减压标志,依据AUDD/PUDD、UNAD/APUD和AUTD/AULD的比值,有助于术中判断硬膜囊、颈神经根和椎动脉的位置。     

颈椎钩突邻近结构薄层断面与MRI对照研究

目的阐明颈椎钩突在薄层断面和MRI断面图像上与周围结构的毗邻关系,为颈椎退行性疾病提供影像学诊断依据。方法选取5例中国数字化可视人体（CVH）数据集中C3-C7椎体上缘清楚显示钩突的薄层断面图像,观察并测量钩突与邻近的椎动脉和颈神经的位置关系,选择对应平面的MRI断面图像对照分析。结果CVH数据集的薄层断面清晰显示颈椎钩突及其周围结构,在断面上测量并得出钩突与颈神经、钩突与椎动脉的距离的平均值,MRI清楚显示颈椎钩突及其邻近结构。结论将CVH数据集中的颈椎钩突平面的薄层断面与对应的MRI图像进行对照研究,可为颈椎病的影像学诊断和治疗提供形态学参考。     

椎动脉和第1颈神经穿经硬膜处的形态学特点及其与高血压颈枕痛的关系

目的　观察椎动脉和第1颈神经穿经硬膜处的形态特点及毗邻结构,探讨高血压合并枕颈部疼痛的发生机制。 方法　头颈部标本18具,解剖剥离法暴露,观察椎动脉穿经硬膜处部位及毗邻结构、椎动脉与第1颈神经（C1）的位置关系。 结果　椎动脉在寰枕外侧关节内后侧穿经硬膜,穿经处形成边缘光滑的圆孔,直径6.5~9.0 mm,硬膜与椎动脉外膜由纤维结缔组织连结。C1神经前后根自脊髓发出向外侧走行于椎动脉内侧并在其下方相伴共同穿经硬膜孔（100%）,其中与动脉壁相贴者66.7%（12例）;神经嵌入动脉壁者22.2%（4例）;隔有硬膜组织者11.1%（2例）。C1神经根出孔后走行于椎动脉与椎动脉沟之间。 结论　椎动脉穿经硬膜孔处位置固定,孔边缘致密,限制椎动脉扩张,利于颈椎活动时维持椎动脉供血,当全身血压波动时椎动脉管径不会产生明显变化,以维持后循环血液动力学稳定,但血压升高有可能将C1颈神经根卡压在硬膜边缘,椎动脉搏动刺激C1颈神经根导致椎枕肌痉挛,出现枕颈部疼痛。这可能是高血压合并枕颈部症状的形态学基础。     

颈椎骨质增生与颈椎病关系的探讨

通过对50例颈椎骨标本的测量,统计了骨质增生的出现率和颈椎各径、钩突各径值及上关节突关节面的角度,比较了正常组与骨质增生组的差异,以阐述骨质增生对颈椎椎管、椎间管的影响,通过对钩突前后径与椎上切迹的相关统计,发现二者呈负相关。随着钩突前后径的增大,椎间管变窄。     

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.     

下颈椎椎动脉孔及其毗邻的解剖学和影像学观测

目的：为下颈椎前路手术预防椎动脉损伤提供解剖学数据。方法：(1)取20具尸体的C3～7段作为解剖标本,作两侧椎动脉孔内缘间距、椎体横、矢径、椎动脉孔内缘和椎弓根内缘间距、椎动脉孔内缘和椎体外缘间距、 椎动脉孔内缘和钩突关节内外缘间距、椎动脉孔前后缘与椎体前后缘的垂直距离、 椎动脉孔矢径的测量。(2)选30例已确诊为颈椎病患者和50例正常人作为检测对象,用CT测量上述数据。 结果： (1) C_3～7两侧横突孔内缘间距、椎体横径、椎体矢径、C_3～6椎动脉孔矢径逐渐增大。(2) 钩突内缘与椎动脉孔内缘间距在6 mm之内, C_3～6椎体外缘与椎动脉孔内缘间距不超过3 mm。(3) C_3～6 横突孔矢径和椎体矢径比值恒定(30.32%～31.86%), C_3～5 椎动脉孔前缘与椎体前缘距离逐渐减小,C_3～5椎动脉孔后缘与椎体后缘距离逐渐增加。结论：本文的测量数值与不同个体的椎动脉资料相结合,为预防椎动脉损伤提供了解剖学依据。     

脊柱颈段的年龄变化及其临床意义

目的 为临床应用提供脊柱颈段年龄性变化的解剖学资料。方法 观察并测量了颈椎干骨标本50套(G3-7)、脊柱颈段标本正中矢状切标本15例(30侧,其中童尸2例,青年5例,中老年8例)、脊柱颈段X线正侧位片320张、CT片50张,分年龄段作统计,对特例作摄影和绘图记录。结果 (1)青少年时期同一椎体的前后面接近平行,并基本等高。随着年龄增加,前面逐渐变斜,朝向前上,前高则逐渐缩短,特别以C4-C6椎为显著,而后面的高度和斜度无显著变化。(2)在老年侧位片上,对同一椎的前、后面分别作垂线,两线相夹的角度C5-6均超过4°,而两端各椎则为3°。(3)颈椎间盘的前高和后高均随年龄老化而降低,但前高降低的总量约为后高者的2倍。(4)钩突年青时呈尖棘状,随着年龄老化向后扩展,变成矢状位的嵴状,此嵴前后长度在上位椎可超过同椎椎体的正中矢状径。(5)骨赘多见于钩突和C4-6椎体前面的上下缘,也可见于关节突和钩椎关节的斜坡,椎体后面可偶见后纵韧带骨化所成的骨赘或骨刺,罕见与前面相当的上、下缘骨唇形成。结论 颈曲随年龄增加而减小,决定因素是椎体前份和椎间盘前份高度的持续降低。     

The terminal insertional segments and communications of the vertebral nerve in the human cervical region

Twenty-four cadavers (48 sides) were used to clarify the terminal insertional segment and communications of the vertebral nerve in the cervical region under a surgical microscope. After displacing the prevertebral muscles (longus colli and longus capitis) laterally, the ventral parts of the transverse foramen of vertebrae (from C2 to C6) were removed, and the insertional segment and communicates of the vertebral nerve surrounding the vertebral artery were observed. The results showed: (1) the vertebral nerve ascended along the ventral or mediodorsal vertebral artery and terminated mainly at C3 (22/36 sides) but not terminated at C4 or C5 only; (2) the superficial communicates from the cervical sympathetic trunk ran in a proximal and distal direction when the fibers entered the anterior branches of the cervical nerves. The fibers running to the proximal direction communicated with the vertebral nerve in the part of transverse foramen; (3) motor and/or sensory rami supplying the prevertebral muscles, corpus vertebrae and intervertebral discs could pass through an "arched-shaped" fiber bundle on the ventral surface of the vertebral artery. In conclusion, the vertebral nerve and the fibers surrounding the vertebral artery could be considered as a stable deep pathway of cervical sympathetic nerves. The deep pathway (vertebral nerve and its branches) with the superficial pathways (cervical sympathetic trunk and its branches) formed a sympathetic nervous "plexus" in the cervical region. This sympathetic nervous "plexus" may be involved in the effects of cervical ganglionic blockade.     

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。     

下颈椎侧方椎间孔镜入路的应用解剖

目的　探讨经下颈椎侧方臂丛后解剖间隙进行椎间孔镜手术的可行性。 方法　40侧成人尸体标本,沿胸锁乳突肌后缘对应C3~7椎体作纵切口,由浅入深经臂丛前、后方按临床手术显露椎间孔途径逐层解剖观测至椎体及附件结构,并模拟手术,牵拉相应组织,测量其牵拉角度、范围。 结果　①臂丛C5~8根长度、根角度及根间距测量结果表明臂丛前、后入路均可直视神经根对椎间孔周围病变进行操作;② C4~6横突与膈神经的距离测量结果表明与臂丛前入路相比,臂丛后入路不易伤及膈神经;③C3~7横突与颈交感干的距离测量结果表明与臂丛前入路相比,臂丛后入路不易伤及颈交感干;④胸导管70%在C7~T1水平汇入静脉角,C7水平臂丛前入路要注意保护胸导管,臂丛后入路不易损伤胸导管;⑤在C7横突水平处将椎动脉向外牵拉的距离为(2.5±0.4)cm,臂丛前、后入路均应注意保护椎动脉;⑥C7横突末端下方至胸膜顶的距离为(1.9±0.4)cm,C7水平臂丛前、后入路均可能伤及胸膜顶。 结论　下颈椎侧方臂丛后解剖间隙可为颈椎间孔镜手术提供安全的手术入路。     

颈椎钩突形态特点及其在前外侧入路减压术中的意义

目的确定钩突的大小,为钩突切除提供形态学基础。方法50套颈椎C     

上颈性眩晕发生的颈交感神经及第2颈神经的解剖学因素观察

目的 明确颈上神经节（superior cervical ganglion,SCG）与第2颈神经及椎动脉的解剖关系,为临床诊治上颈性眩晕提供形态学基础。 方法 解剖15具（30侧）成人尸体标本,观察颈上神经节与C2的交通支及至椎动脉的分支。 结果 5侧未见SCG与C2之间存在神经连接;25侧存在神经连接,其中18侧存在迷走神经参与,7侧可见SCG分支支配椎动脉。SCG分支与C2前支汇合后,交感神经纤维分别至C2前、后支及椎动脉。 结论 SCG与C2的交通支及其对椎动脉的支配关系,可为阐明上颈性眩晕发病机理及建立有效治疗方案提供重要解剖学依据。     

展神经池段的动脉供应及其与邻近血管的关系

目的：研究展神经池段的动脉供应及其与邻近血管的关系。方法：选取18例脑千，观测展神经根池段的滋养动脉来源及其与邻近血管的关系。结果：从展神经根腹面跨过的有小脑下前动脉、脑桥下外侧动脉、小脑下后动脉、迷路动脉、小脑下后和小脑下前动脉总干、椎动脉；从展神经背面跨过的血管有小脑下前动脉、脑桥下外侧动脉等。展神经的滋养动脉主要来自脑桥前外侧穿动脉、小脑下前动脉和脑桥下外侧动脉。接触和压迫展神经根的血管主要是小脑下前动脉和移位的基底动脉或椎动脉，占16．7％，结论：展神经的滋养动脉损伤和血管压迫可导致展神经麻痹，了解展神经的动脉供应及其邻近血管关系对临床诊断和手术治疗具有重要参考作用。     

部分钩突切除对颈椎稳定性影响的有限元分析

目的建立颈椎(C4-C6)三维有限元模型,研究钩突切除前后对颈椎稳定性的影响。方法根据健康志愿者的颈椎断层CT扫描序列图像,采用Mimics13.1和Solid Works2012软件进行三维重建和造型,利用ANSYS15.0软件,对颈椎及周围组织赋予不同的材料属性,建立颈椎(C4-C6)三维有限元模型。在建立的模型上加载,模拟脊柱的前屈、后伸、左右侧曲、左右旋转6种工况下的生理活动,获取位移、应力等数值云图,并进行分析验证。在C5节段左侧钩突上分别切除钩突高度的25%、50%和60%,获得不同范围钩突切除时的左侧弯状态下颈椎各部位的位移、应力等数值云图,分析不同范围钩突切除对颈椎稳定性的影响。结果本研究建立了三个椎体运动节段的三维有限元模型,模型高度模拟颈椎结构与材料特性,研究了不同范围钩突切除后,颈椎稳定性受到的影响。钩突切除高度的25%后的左侧弯状态与未切除时对比分析,位移云图变化不大,最大等效应力减小。钩突切除高度的50%、60%后的左侧弯状态下的位移继续增大,最大等效应力逐渐减小。结论切除钩突高度的25%时对颈椎稳定性影响不大,随着切除钩突范围的增加,颈椎的稳定性逐渐降低。