Geometry of the Intervertebral Volume and Vertebral Endplates of the Human Spine

Replacement of a degenerated vertebral disc with an artificial intervertebral disc (AID) is currently possible, but poses problems, mainly in the force distribution through the vertebral column. Data on the intervertebral disc space geometry will provide a better fit of the prosthesis to the vertebrae, but current literature on vertebral disc geometry is very scarce or not suitable. In this study, existing CT-scans of 77 patients were analyzed to measure the intervertebral disc and vertebral endplate geometry of the lumbar spine. Ten adjacent points on both sides of the vertebrae (S1-superior to T12-inferior) and sagittal and transverse diameters were measured to describe the shape of the caudal and cranial vertebral planes of the vertebrae. It was found that the largest endplate depth is located in the middle or posterior regions of the vertebra, that there is a linear relationship between all inferior endplate depths and the endplate location (p < 0.0001) within the spinal column, and that the superior endplate depth increases with age by about 0.01 mm per year (p < 0.02). The wedge angle increases from T12-L1 to L5-S1. The results allow for improvement of the fit of intervertebral disc-prostheses to the vertebrae and optimized force transmission through the vertebral column.     

C 5/6 椎间隙不同撑开高度对临近椎间盘压力的研究分析

目的　研究C5/6椎间隙不同撑开高度对临近椎间盘压力的影响,以期能对临床工作中选择合适的椎间撑开高度提供依据。 方法　选取6具新鲜成人尸体上的颈椎制作标本,将制作好的标本放在BOSE动/静态材料试验机上加载中立、屈伸、侧弯、旋转的多维运动,分别测试在不同运动载荷下C5/6椎间隙撑开前,C5/6椎间隙撑开基准高度100%、120%、140%、160%时C4/5及C6/7椎间盘压力变化,对测得的压力值进行多重统计学比较分析。 结果　所有撑开器位置安装满意,统计分析显示：6例标本C5/6的平均高度值为6.8 mm;在不同椎间撑开高度下,颈椎后伸30°位时椎间盘压力最小(P<0.05),有统计学意义;在120%的基准高度时,颈椎后伸30°位、左右侧弯30°位时C4/5与C6/7椎间盘压力值分别比其它基准高度测得压力值小(P<0.05),有统计学意义;颈椎中立位时C4/5与C6/7椎间盘压力均小于100%、140%、160%时基准高度测得压力值,而大于未撑开前测得的椎间盘压力值;左右侧屈时,120%平均高度时C4/5,C6/7椎间盘压力值小于140%平均高度(P<0.05),且两者与其他3种高度两两比较均有显著性差异(P<0.05);左右旋转：各状态两两比较无显著差异(P>0.05);1例标本在撑开160%的基准高度行前屈30°位时,出现关节突的关节囊韧带轻微撕裂。 结论　C5/6椎间盘摘除行椎间植骨时,选取基准高度的120%作为椎间隙撑开高度,对临近椎间盘压力变化影响较小,为合适的椎间隙撑开高度。     

Posterior distraction forces of the posterior longitudinal ligament stratified according to vertebral level

Introduction Although considered significant in resisting midline intervertebral disc herniation, the posterior longitudinal ligament (PLL) has had relatively few studies performed regarding its morphology and function. We performed the present experiment to discern the amount of posterior tensile force necessary to disrupt the PLL at each vertebral level. Materials and methods Twenty-five adult cadavers underwent laminectomies of vertebrae C1 to S1. After removal of the spinal cord, nerve roots, and dura mater, the PLL was identified for each vertebral level and a steel wire placed around its waist in the midline and a tensile gauge attached and posterior tension applied perpendicular to the spine. Forces necessary to failure of the PLL were noted for each vertebral level. Results The PLL was found to be stronger in the thoracic spine compared to the cervical and lumbar vertebrae (P < 0.05). Dividing the vertebral levels in this manner, we found an average posterior distraction force to failure of 48.3 N in the cervical region, 61.3 N in the thoracic region, and 48.8 N in the lumbar region. Conclusions These findings support clinical observations that thoracic disc herniation is rare. We hypothesize that this clinical observation is partially due to a stronger PLL in the thoracic spine.     

颈椎终板Modic改变分布特点与退变的关系

背景：关于Modic改变在腰椎中分布及特点的相关性研究比较多,而在颈椎中的相关研究则较少。 目的：分析颈椎终板Modic改变的临床分布特点,并探讨其发生与颈椎退变的相关性。 方法：随机抽取因颈肩痛行颈椎MRI和常规X射线检查的患者共200例,年龄20~83岁。记录MRI颈椎Modic改变发生的节段,改变类型,改变的位置等,并分析其发生与性别、年龄、椎间盘退变节段及程度、椎间隙高度、颈椎曲度的相关性。 结果与结论：200例共计1 200个颈椎椎间盘中23例(11.5%),29个(2.4%)个椎间盘邻近终板发生Modic改变。Ⅰ型8例(4%),10个椎间盘(0.8%);Ⅱ型13例(6.5%),16个椎间盘(1.3%);Ⅲ型2例(1.0%),3个椎间盘(0.25%)。按照各个椎间盘节段发病数统计,C2/3节段O个,C3/4节段4个,C4/5节段6个,C5/6节段12个,C6/7节段7个,C7/T1节段0个,发病率分别为0%,0.33%,0.5%,1.0%,0.58%,0%。结果表明颈椎终板也存在Modic改变的现象,但发生率较腰椎低,Ⅱ型最多见,Ⅰ型次之,Ⅲ型最为少见,多发生于C5/6椎间盘,多位于邻近终板的后方。50岁以上为其好发年龄,其发生与年龄、椎间盘退变、椎间盘节段及颈椎曲度之间存在相关性。     

椎体截面的数理学原理分析与脊柱病变的探讨

目的　测量脊柱椎体终板截面的横径与矢径,利用数理学原理分析脊柱椎体-椎间盘受力传递规律,分析人体脊柱椎体-椎间盘的受力规律与临床病理联系。 方法　测量10具完整脊柱标本C2~S1各椎体上下截面的横径（L）、矢径（H）,运用几何学相似原理:椎体/椎间盘上下截面面积变化可近似用数学方程表达,S1/S2=(a*b)/(A*B),S=π/4*L*H,分析椎体上下截面的结构规律;根据椎间盘的结构,利用物理学静水液压原理：F1/F2=S1/S2,分析椎间盘压力变化规律;根据数理学原理推测脊柱椎体-椎间盘的结构与力学规律。 结果　脊柱椎体截面的结构从C2下截面到L4下截面面积呈“S”形曲线递增,L4下截面面积最大,L4下截面到S1上截面递减;椎体-椎间盘间截面横径矢径决定其椎体截面面积、压力系数K,K=L*H。 结论　脊柱椎体-椎间盘自身结构决定了脊柱特有的力学传递与分布规律;建立数理学方程来认识脊柱的结构与力学传递规律能更直观的理解与观察脊柱力学特性与临床脊柱病变规律。     

Age dependent changes in cervical region of the spine according to data of nuclear magnetic tomography

Morphological characteristics of spine cervical region were studied in 132 patients (62 female and 70 male) aged 12-76 years using magnetic resonance tomography. The imaging was performed with the use of T1 and T2--weighting regimes. The study revealed sex- and age-dependent differences in the dimensions of cervical vertebrae. Height and sagittal dimensions of vertebral bodies were significantly smaller in females than in males. With advancing age the reduction in vertebral body height was more expressed in women, while the increase of vertebral body sagittal dimensions was similar in both males and females. The sagittal dimension of vertebral canal was correlated with sagittal dimension of vertebral body (r = 0.69) in males and with transverse dimension of vertebral body (r = 0.82) in females. The data obtained should be taken into consideration during evaluation of the state of bony structures of cervical vertebrae, intervertebral discs and in the diagnosis of pathological processes in the spine cervical region.     

脊柱内固定后椎间盘营养途径的实验研究

目的：为了研究脊柱内固定后椎间盘的营养途径。方法：24只日本大耳白兔，行墨汁灌注后，观察同一动物非固定区中椎间盘与固定区域椎间盘的墨汁分布情况，观察相同位置对照组与实验组的墨汁分布情况。结果：软骨终板有血管从中经过，椎间盘营养来源分主要和次要途径，内固定后软骨终板和椎体之间产生分离，椎间盘会新生较多小血管，且血管缓慢而淤积。结论：内固定节段椎间盘处于低应力状态下，一定时间后，营养代谢的改变会导致椎间盘退行样变的发生。     

Lumbar muscularity and its relationship with age,occupation and low back pain

Summary This paper considers an internal standard of lumbar muscularity. The cross-sectional areas (A _cs) of the intervertebral disc and paraspinal muscles were measured in 147 working men from an axial magnetic resonance image passing through the L3-4 disc. Lumbar muscularity was expressed by two ratios; the ratio between the A _cs of the right psoas and the A _cs of the intervertebral disc (P:disc), and the ratio between the combined A _cs values of the right erector spinae and quadratus lumborum and the A _cs of the disc (ESQL:disc). When the subjects were divided into two age groups (76 aged 20–30 years and 71 aged 31–58 years) lumbar muscularity was found to be significantly greater (P < 0.001) in the younger age group (P:disc=0.8, SD 0.2; ESQL:disc=2.0, SD 0.3) than in the older age group (P:disc =0.7, SD 0.2; ESQL:disc=1.8, SD 0.3). Lumbar muscularity was not significantly affected by occupation or by a history of low back pain.     

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。     

脊柱跟随载荷在离体生物力学应用研究中的进展

阐述跟随载荷在维持脊柱生物力学中的重要性,归纳近年来人离体脊柱标本跟随载荷模拟的各种方法及手段。通过与人体脊柱各椎体活动度、椎间盘内压等真实数据对比,从力学角度分析各类模拟手段的可行性,总结人体颈椎、胸椎、腰椎离体生物力学实验中最适合的加载载荷及扭矩,并探讨常规脊柱内固定术式对脊柱生物力学特性的影响。     

不同方式颈椎融合手术对上颈椎Jefferson骨折稳定效果的影响

目的建立人体上颈椎C0～3节段Jefferson骨折有限元模型,分析后路寰枢椎融合(posterior atlantoaxial fusion,PSF)和枕颈融合(occipitocervical fusion,OCF)对颈椎椎体生物力学特性和钉棒系统力传导特性的影响。方法基于CT图像建立人体上颈椎C0～3节段Jefferson骨折模型,依据临床手术方案实施PSF、OCF1和OCF2内固定术,施加50 N集中力和1.5 N·m力矩于枕骨底部,研究上颈椎C0～3节段在前屈、后伸、侧屈和旋转运动时,颈椎椎体的应力分布和关节活动度(range of motion,ROM)、钉棒系统最大应力以及椎间盘的应力分布情况。结果 OCF1和OCF2椎体ROM较PSF增加,钉棒应力减少,OCF具有较好的固定效果。结论 PSF、OCF1、OCF2固定术式均可减少上颈椎ROM,重建上颈椎的稳定性,使椎体和椎间盘应力分布趋向正常水平。研究结果可为临床手术方案提供理论依据。     

The Effects of Age on the Morphometry of the Cervical Spinal Cord and Spinal Column in Adult Rats: An MRI‐Based Study

Rat models are commonly used to investigate the pathophysiological pathways and treatment outcomes after spinal cord injury (SCI). The high incidence of fall‐induced SCI in older adults has created a need for aging models of SCI in rats to investigate potential age‐related differences in SCI severity and outcomes. The aims of this study were to determine the influences of age and vertebral level on the geometries of the cervical spinal cord and spinal column in a rat model. Three young (3 months) and three aged (12 months) Fischer 344 rats were imaged in a high field (7 T) small‐animal magnetic resonance imaging system. All spinal cord geometry variables (including depth, width, and axial cross‐sectional area) and one spinal canal variable (depth) were significantly larger in the aged specimens by an average of 8.1%. There were main effects of vertebral level on all spinal cord variables and four spinal canal variables with values generally larger at C4 as compared to C6 (average increases ranged from 5.7% to 12.9% in spinal cord measures and 5.4% to 6.8% in spinal canal measures). High inter‐rater reliability between two measurers was observed with a mean intraclass correlation of 0.921 and percent difference of 0.9% across all variables measured. This study clearly demonstrates that cervical spinal cord geometry changes between the ages of 3 and 12 months in Fischer 344 rats. This information can aid in the planning and interpretation of studies that use a rat model to investigate the influence of age on cervical SCI. Anat Rec, 297:1885–1895, 2014. © 2014 Wiley Periodicals, Inc.     

Finite element modeling of the cervical spine: role of intervertebral disc under axial and eccentric loads

An anatomically accurate, three-dimensional, nonlinear finite element model of the human cervical spine was developed using computed tomography images and cryomicrotome sections. The detailed model included the cortical bone, cancellous core, endplate, lamina, pedicle, transverse processes and spinous processes of the vertebrae; the annulus fibrosus and nucleus pulposus of the intervertebral discs; the uncovertebral joints; the articular cartilage, the synovial fluid and synovial membrane of the facet joints; and the anterior and posterior longitudinal ligaments, interspinous ligaments, capsular ligaments and ligamentum flavum. The finite element model was validated with experimental results: force–displacement and localized strain responses of the vertebral body and lateral masses under pure compression, and varying eccentric anterior-compression and posterior-compression loading modes. This experimentally validated finite element model was used to study the biomechanics of the cervical spine intervertebral disc by quantifying the internal axial and shear forces resisted by the ventral, middle, and dorsal regions of the disc under the above axial and eccentric loading modes. Results indicated that higher axial forces (compared to shear forces) were transmitted through different regions of the disc under all loading modes. While the ventral region of the disc resisted higher variations in axial force, the dorsal region transmitted higher shear forces under all loading modes. These findings may offer an insight to better understand the biomechanical role of the human cervical spine intervertebral disc.     

激光扫描多平面动态测量下颈椎椎间高度退变后椎间孔的变化

目的　激光扫描三维重建后动态测量下颈椎椎间高度退变时相应节段椎间孔的变化,为临床诊治神经根型颈椎病提供新的思路和参考。 方法 选用6具新鲜成人尸体颈椎标本,以C5/6单节段脊柱功能单位（FSU）作为研究对象。椎间盘切除后将C5/6椎间高度置于基准高度状态,激光扫描仪扫描收集该状态下C5/6 FSU的空间关系信息,再对骨性单椎体进行全面扫描,在Geomagic Studio8.0软件中再现　C5/6基准状态,并模拟6种椎间高度退变模型,即C5椎向C6椎椎体面趋于平行移动基准高度的10%、　20%、30%、40%、50%和60%。多平面动态测量方法（MPDM）分别测量椎间孔容积、中间面积、内口以及外口面积。 结果 测量数据显示随着椎间高度持续的下降,椎间孔的容积和面积逐渐减小,当椎间高度丢失基准高度30%时,椎间孔中间面积首先开始与基准状态有显著性差异（P=0.003）。 结论 激光扫描三维重建原貌再现骨性表面,是获得精确测量数据的前提;动态测量的方法较为客观准确,是测量椎间孔的理想方法;测量发现在下颈椎骨性椎间孔随着椎间高度在下降而缩小,其中间面积首先发生显著缩小,提示此处容易发生狭窄而引起临床症状。     

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.     

颈椎人工椎间盘置换有限元分析

目的　建立C4~5节段PrestigeTM-LP颈椎人工椎间盘植入后的三维有限元模型,进行手术节段的运动分析。 方法 采用对成年男性的新鲜尸体的颈椎标本进行CT三维扫描方法建立C4~5节段和PrestigeTM-LP人工间盘有限元,模拟完成C4~5人工椎间盘置换手术。测量生理加载下手术节段前屈/后伸、侧弯及轴向旋转运动角度。结果 有限元模型对颈椎的结构,包括椎体间韧带、颈椎关节突关节、钩椎关节等均进行了精确的重建,并较好地模拟手术操作进行PrestigeTM-LP人工间盘植入。运动加载后运动角度,前屈5.7°,后伸3.5°,侧弯5.0°,旋转11.3°,与文献报道结果较为接近。 结论　有限元模型具有精确度高,手术模拟真实的特点,可作为颈椎人工椎间盘生物力学研究的一种较好途径。PrestigeTM-LP颈椎人工椎间盘置换可较好地保留手术节段的运动功能。     

Relationships between the height of intervertebral discs and the degree of lordosis of the cervical spine in children. A roentgenometric study (author's transl)]

On lateral roentgenograms of the cervical spine of 120 normal children between 3 and 14 years of age the ventral and dorsal height of all 5 intervertebral discs were measured and the "index of the intervertebral disc" was calculated. In addition, the "degree of lordosis" of the cervical spine was determined according to ISHIHARA (1964). Evaluation was in 3 age groups: 3 to 6, 7 to 10, 11 to 14 years; and the arithmetic mean and standard deviation were calculated for each group. All intervertebral discs are more or less "cuneiform" (ventrally higher than dorsally); they narrow from cranial to caudal. In children the degree of lordosis of the cervical spine shows a continuous decrease with advancing years. In all age groups girls show a lower degree of lordosis than boys. Statistically the differences of average values of the intervertebral-disc-index among the various shapes of the cervical spine in neutral position (straight, sublordotic, lordotic and hyperlordotic) are highly significant. By means of roentgenometric methods our examinations demonstrate that the lordotic curvature of the healthy cervical spine primarily depends on the cuneiform shape of intervertebral discs.     

零切迹颈椎椎间融合器解剖学参数测量

目的　通过测量正常国人的颈椎椎间隙解剖学参数，为设计符合国人的颈椎前路零切迹椎间融合器提供理论依据。 方法　纳入200例健康志愿者，在标准颈椎正侧位X线片上测量颈C2~3、C3~4、C4~5、C5~6、C6~7椎间隙的前缘、中点、后缘高度，椎间隙横径，椎间隙矢状径，螺钉进钉的最佳角度和深度，椎间盘角。分别计算各解剖参数的均值和标准差。 结果　纳入男性志愿者100人，平均年龄31.21岁，女性志愿者100人，平均年龄31.05岁。男性组椎间隙横径为（19.88±1.06）mm，矢状径（19.42±1.59）mm，前缘高度（5.57±0.74）mm，中点高度（7.24±0.98）mm，后缘高度（4.11±0.27）mm；上位螺钉进钉的最佳深度为（33.54±1.14）mm，下位螺钉进钉的最佳深度（24.35±1.53）mm；上位螺钉进钉的最佳角度为（41.10±2.86）°，下位螺钉进钉的最佳角度为（47.13±3.17）°；椎间盘角为（4.94±1.36）°。女性组椎间隙横径为（18.29±0.89）mm，矢状径（13.76±1.41）mm，前缘高度（5.12±0.64）mm，中点高度（6.68±0.67）mm，后缘高度（3.20±0.25）mm；上位螺钉进钉的最佳深度为（25.18±1.75）mm，下位螺钉进钉的最佳深度为（21.83±1.66）mm；上位螺钉进钉的最佳角度为（41.66±2.70）°，下位螺钉进钉的最佳角度为（47.03±2.43）°；椎间盘角为（4.80±1.38）°。男性组与女性组各参数对比，差异无统计学意义（P>0.05）。同节段椎间隙前、中、后缘高度均存在统计学差异，表现为后缘高度<前缘高度<中点高度（P<0.05）。 结论　通过正常人群颈椎X线解剖学测量，可获得设计零切迹颈椎椎间融合器的国人数据。     

零切迹颈椎椎间融合器解剖学参数测量

目的　通过测量正常国人的颈椎椎间隙解剖学参数,为设计符合国人的颈椎前路零切迹椎间融合器提供理论依据。 方法　纳入200例健康志愿者,在标准颈椎正侧位X线片上测量颈C2~3、C3~4、C4~5、C5~6、C6~7椎间隙的前缘、中点、后缘高度,椎间隙横径,椎间隙矢状径,螺钉进钉的最佳角度和深度,椎间盘角。分别计算各解剖参数的均值和标准差。 结果　纳入男性志愿者100人,平均年龄31.21岁,女性志愿者100人,平均年龄31.05岁。男性组椎间隙横径为（19.88±1.06）mm,矢状径（19.42±1.59）mm,前缘高度（5.57±0.74）mm,中点高度（7.24±0.98）mm,后缘高度（4.11±0.27）mm;上位螺钉进钉的最佳深度为（33.54±1.14）mm,下位螺钉进钉的最佳深度（24.35±1.53）mm;上位螺钉进钉的最佳角度为（41.10±2.86）°,下位螺钉进钉的最佳角度为（47.13±3.17）°;椎间盘角为（4.94±1.36）°。女性组椎间隙横径为（18.29±0.89）mm,矢状径（13.76±1.41）mm,前缘高度（5.12±0.64）mm,中点高度（6.68±0.67）mm,后缘高度（3.20±0.25）mm;上位螺钉进钉的最佳深度为（25.18±1.75）mm,下位螺钉进钉的最佳深度为（21.83±1.66）mm;上位螺钉进钉的最佳角度为（41.66±2.70）°,下位螺钉进钉的最佳角度为（47.03±2.43）°;椎间盘角为（4.80±1.38）°。男性组与女性组各参数对比,差异无统计学意义（P>0.05）。同节段椎间隙前、中、后缘高度均存在统计学差异,表现为后缘高度<前缘高度<中点高度（P<0.05）。 结论　通过正常人群颈椎X线解剖学测量,可获得设计零切迹颈椎椎间融合器的国人数据。     

颈椎前路钢板并轴向螺钉固定治疗屈曲牵张型损伤的解剖学研究

目的　提出一种联合颈椎前路钢板固定治疗屈曲牵张型颈椎损伤的新术式-颈椎轴向螺钉固定术,进行解剖学可行性研究。 方法 随机调取50例正常成年志愿者的颈椎侧位片。年龄22～48岁,平均28岁。通过JW-PACS图像系统,测量C2～6椎体高度;C2/3～C5/6椎间盘高度以及椎间盘矢径;并模拟轴向螺钉固定,即下位椎体前下缘至上位椎体后上缘的连线,测量轴向螺钉最大长度、头倾角以及植骨块深度等。采用一例防腐成人尸体标本,在C臂X线机透视下,模拟颈椎前路钢板固定并颈椎轴向螺钉固定术。 结果 轴向螺钉最大长度为(41.18±3.92)mm,轴向螺钉头倾角为（25.21±3.58）°。植骨块合适深度应小于椎间盘矢径（17.09±1.50）mm,且大于（11.69±1.63）mm,即略大于12 mm。尸体模拟手术表明,颈椎前路轴向螺钉固定在C2/3、C3/4、C4/5、C5/6均可以顺利完成, C6/7节段由于胸骨阻挡,无法进行轴向螺钉固定。 结论 颈椎前路钢板并轴向螺钉固定术治疗屈曲牵张性损伤具有操作可行性。