Morphometric analysis of vertebrae and intervertebral discs as a basis of disc replacement

In this study measurements were obtained from 359 vertebrae and 215 intervertebral discs in an attempt to classify discs by their size. At the cervical and thoracic levels, this attempt was unproductive because of extensive variations. In the lumbar spine, discs were allocated to six size-matched groups. The breadth of marginal rims were also measured with a view to provide surgeons operating on the spine with precise data on disc morphology to facilitate dise replacement.     

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。     

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.     

人工颈椎间盘置换术的解剖学参数测量

目的：为人工颈椎间盘假体置换术提供解剖学参数。方法：志愿者43人，其中男性24人（22-43岁，平均年龄31．04岁），女性19例（23-39岁，平均年龄30．16岁）测量颈椎间盘215个。测量中立、屈曲、过伸位颈椎侧位X线片C2，3、C3，4、C4，5、C5，6、C6，7椎间隙前、后缘以及椎间隙中央的高度，数据进行统计和分析。结果：中立位、屈曲位、过伸位颈椎侧位片显示各颈椎间隙高度，不同性别、间隙、部位、姿态间存在显著差异（P=0．000），屈伸运动中，椎间盘前缘的运动幅度较中部和后缘大，屈曲时颈椎间盘前份和中央部均被显著压缩。结论：生理状态，屈伸运动中，椎间盘前部的运动占整个椎间盘运动幅度的绝大部分，椎间盘设计、制造和临床运用中，维持目标椎间隙前部的高度和活动度至关重要。     

Morphometric analysis of the relationships between intervertebral disc and vertebral body heights: an anatomical and radiographic study of the human thoracic spine

The main aim of this study was to provide anatomical data on the heights of the human intervertebral discs for all levels of the thoracic spine by direct and radiographic measurements. Additionally, the heights of the neighboring vertebral bodies were measured, and the prediction of the disc heights based only on the size of the vertebral bodies was investigated. The anterior (ADH), middle (MDH) and posterior heights (PDH) of the discs were measured directly and on radiographs of 72 spine segments from 30 donors (age 57.43 ± 11.27 years). The radiographic measurement error and the reliability of the measurements were calculated. Linear and non-linear regression analyses were employed for investigation of statistical correlations between the heights of the thoracic disc and vertebrae. Radiographic measurements displayed lower repeatability and were shorter than the anatomical ones (approximately 9% for ADH and 37% for PDH). The thickness of the discs varied from 4.5 to 7.2 mm, with the MDH approximately 22.7% greater. The disc heights showed good correlations with the vertebral body heights (R(2), 0.659-0.835, P-values < 0.005; anova), allowing the generation of 10 prediction equations. New data on thoracic disc morphometry were provided in this study. The generated set of regression equations could be used to predict thoracic disc heights from radiographic measurement of the vertebral body height posterior. For the creation of parameterized models of the human thoracic discs, the use of the prediction equations could eliminate the need for direct measurement on intervertebral discs. Moreover, the error produced by radiographic measurements could be reduced at least for the PDH.     

Prenatal and postnatal development of the cervical portion of the spine in the short-finned pilot whale Globicephala macrorhyncha

Fusion of the cervical spine in Globicephala macrorhyncha is a prenatal rather than postnatal phenomenon which encompasses all cervical vertebra. This results in a relatively short, nonarticulated, composite cervical spine in this particular species. Cervicothoracic spine segments removed from fetuses demonstrated complete fusion of all cervical vertebra commencing during early prenatal development. C1 and C2 initially developed as a composite central cartilaginous unit, although laterally there was some separation through rudimentary interzone formation. However, C3 through C7 formed individual cartilaginous centra which were divided from each other by thin, well-demarcated interzones, but without the formation of intervertebral discs (which were concomitantly evident dividing the thoracic, lumbar, and caudal vertebra, and were also present between the seventh cervical and first thoracic vertebra, although this was a very rudimentary intervertebral region). The first primary ossification center appeared in C2. Subsequently, primary ossification occurred in C7, and finally in C2 through C6, with ossification progressing in a craniocaudal fashion in these four vertebra. The centra ossification centers then progressively coalesced in the midline, from C2 to C7, in a craniocaudal sequence. This entire chondroosseous fusion process was completed during early gestation (probably less than 2 to 3 months of prenatal development), so that a composite “single” cervical vertebra developed that characterizes this species at birth and throughout postnatal development. Postnatally, ossification spreads laterally within each centrum, and also progressively removes the vestiges of the intervertebral material. C7 also develops a secondary ossification center, but only in the caudal region. The cranial end of C7 and the remainder of the cervical vertebra do not form secondary centers. An extensive fibrocartilaginous/hyaline cartilage bridge remains between C1 and C2, even after closure of the vertebral physes. Undoubtedly, this allows continued growth in C1 and C2, which become the dominant portion of the cervical unitary vertebra. Eventually, even this synchondrosis will disappear to form a completely osseous cervical mass.     

腰椎间盘退变MRI：与Modic改变相关的影像学分析

背景：部分椎间盘源性下腰痛患者MRI可出现Modic改变,但Modic改变的相关因素及Modic改变与椎间盘退变之间因果关系目前尚不十分清楚。 目的：分析存在腰椎间盘Modic改变的下腰痛患者性别、年龄分布特点及腰椎间盘发生Modic改变的相关因素。 方法：回顾性分析634例(2 536个椎间盘)存在腰椎间盘Modic改变患者的性别、年龄分布特点,并分析腰椎间盘Modic改变与椎间盘突出或膨出、Schmorl结节、椎体滑脱、椎间盘解剖水平及椎间盘退行性改变程度的相关性。 结果与结论：634例患者中,女性患者ModicⅡ、Ⅲ型出现率均较男性高,而ModicⅠ型出现率小于男性患者(P < 0.001);40岁以上患者较40岁以下患者Modic各型改变的出现率均高(P < 0.001)。2 536个腰椎间盘中,有椎体滑脱、出现Schmorl结节、有椎间盘突出或膨出者Modic各型改变的出现率均比无此类表现者高(P < 0.001);L4/5、L5/S1水平(低位)Modic各型改变的出现率均比L2/3、L3/4水平(高位)高(P < 0.001);椎间盘退行性改变越严重,Modic各型改变的出现率越高(P < 0.001)。椎间盘退行性改变分级、Schmorl结节与Modic改变有显著相关性。结果说明,腰椎间盘Modic改变与患者性别、年龄、椎间盘有无突出或膨出、有无Schmorl结节、椎体有无滑脱、椎间盘解剖水平及椎间盘退行性改变分级均有相关性。其中,椎间盘退行性改变分级、Schmorl结节与腰椎间盘Modic改变间的相关性最高,且椎间盘退行性改变分级较Schmorl结节与之相关性更高。     

不同腰椎生理曲度下牵引的三维有限元分析

文题释义：腰椎牵引：是指令患者平卧于治疗床上,使用束带将患者前臂固定,达到医者固定患者双臂的目的;波浪式滚动气柱以腰背部为作用点进行顶推,控制多层气柱叠加高度使受试者腰部逐渐过伸牵引脊柱关节,实现对软组织的牵伸,并结合自身重力过伸牵引脊柱关节,能够增大椎间隙及调整椎小关节,最终达到理筋整复的作用。 三维有限元分析：是指在获取腰椎的CT图像数据,并导入到Mimics等软件当中建立的有限元模型基础上,将L₃的发生的位移变化带入MSC.Nastam软件中,高度仿真模拟人体在不同生理曲度下,计算分析出全腰椎各节段椎体、椎间关节、椎间盘、前纵韧带的应力值及分布情况的变化。 背景：近年来利用有限元分析方法研究腰椎生物力学成为热点,研究认为腰椎生理性前凸可减少腰椎间盘压力负荷,而对腰椎起保护效应。 目的：研究腰椎在正常生理曲度、屈曲位及最大过伸位下进行腰椎牵引时对L₁-L₅腰椎各节段的生物力学效应,并评估腰椎牵引的最佳生理曲度。 方法：选取1名健康男性志愿者,26岁,身高174 cm,体质量60 kg,既往体健,排除腰椎骨骼异常疾病。以受试者L₃为作用点徒手操作南少林倒盖金被法,利用DR机分别获得受试者腰椎起始位和最大过伸位的腰椎侧位片,构建全腰椎有限元模型。计算腰椎不同生理曲度下全腰椎各节段椎体、椎间关节、椎间盘、前纵韧带的应力值及分布情况的变化。研究方案的实施符合福建中医药大学附属康复医院相关伦理要求,受试者对试验过程完全知情同意。 结果与结论：①模拟腰椎前屈、后伸,左右侧弯,左右旋转6种工况活动度：L₁-L₂的前屈与后伸活动度之和为9.31°,左右侧弯9.84°,左右旋转4.43°;L₂-L₃：前屈与后伸10.22°,左右侧弯12.35°,左右旋转4.57°;L₃-L₄的前屈与后伸的活动度之和为11.20°,左右侧弯11.63°,左右旋转5.32°;L₄-L₅前屈与后伸活动度之和13.16°,左右侧弯11.58°,左右旋转5.05°;②在正常生理曲度牵引腰椎时,腰椎各个结构的应力值远大于过伸位牵引的应力值;前纵韧带应力值正常曲度是2.47 MPa,过伸位是21.20 MPa;L₃的椎体应力值达到最大,是过伸位牵引应力值的4倍;L₂-L₃的椎间关节及椎间盘的应力值在腰椎各个节段是最大的;③结果说明,腰椎在过伸位较正常生理曲度牵引下椎体、椎间关节、椎间盘的压力减轻更大,而且前纵韧带的压力值始终在安全范围内。腰椎在过伸位牵引时可能获得更好的临床疗效,同时具备一定的安全性。 ORCID: 0000-0002-4468-1464(李民) 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

中国人腰椎间盘结构与人工椎间盘置换相关的参数测量

背景：全椎间盘置换已应用多年,但国内鲜见对人腰椎间盘结构测量的大样本系统研究。 目的：为中国人腰椎间盘假体置换手术和设计提供参考数据。 方法：选取中国成年尸体41具(男22例,女19例),解剖获得完整的腰椎标本。测量椎体软骨板断面厚度。随机抽取正常成年人标准腰椎正侧位X射线片157例(男89例,女68例)。测量椎体上/下横径、上/下矢状径和椎间隙高度。 结果与结论：成年尸体及正常成年人标准腰椎正侧位X射线片显示腰椎间盘软骨板厚度、椎体上/下横径、矢状径和椎间隙高度均不存在性别差异(P > 0.05)。除L1/2相邻椎体矢状径、L3/4相邻椎体横径和L4/5相邻椎体矢状径外,其余椎间盘相邻椎体横径或矢状径的差异有显著性意义(P < 0.05),但各径线实测数值之间差距均较小。腰椎间隙自L1/2至L4/5逐渐增宽,前缘高度大于后缘高度。L5/S1椎间隙与其他腰椎间隙存在较大差异,其相邻终板间夹角明显增大。     

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.     

颈椎椎间盘的解剖学测量

颈椎椎间盘退变及病变是引起颈肩痛的常见原因之一。近年来许多学者对颈椎椎间盘的形态学及生物力学特征作了较系统的研究。但以往认为颈椎间盘突出症较少见。对颈椎髓核位置、椎间盘前、中、后三部分高度解剖学测量的文献报道较少。本研究在青年新鲜尸体的颈椎上。对颈椎髓核位置、椎间盘前、中、后三部分高度等,做了较为系统的解剖学测量。旨在为人体解剖学积累资料,为临床应用提供形态学依据;并对其临床意义进行了讨论。     

腰椎间盘的扩散张量成像观测及临床应用

目的　为腰椎间盘退变导致的腰腿痛等病症的临床诊断提供影像学依据。 方法　选取脊柱腰段扩散张量成像（DTI）扫描检查正常者200例和腰椎间盘退变者100例,在工作站划分腰椎间盘和腰椎间盘退变的感兴趣区,测量感兴趣区的表观扩散系数（ADC）和各向异性分数（FA）,比较不同解剖部位、年龄组腰椎间盘和不同Pfirrmann分级腰椎间盘退变的FA、ADC值。 结果　不同解剖部位腰椎间盘的FA值和ADC值均有统计学差异（P<0.05）,L1~2、L2~3、L3~4椎间盘的FA值逐渐降低,L4~5、L5~S1椎间盘的FA值则逐渐增高;L1~2、L2~3、L3~4椎间盘的ADC值逐渐增高,L3~4、L4~5、L5~S1椎间盘的ADC值则无明显变化。不同年龄组腰椎间盘的FA值无统计学差异（P>0.05）,ADC值有统计学差异（P<0.05）,随着年龄增长ADC值逐渐降低。不同Pfirrmann分级腰椎间盘退变的FA值和ADC值均有统计学差异（P<0.05）,随着Pfirrmann分级增高,FA值逐渐增高,ADC值逐渐降低。 结论　解剖部位、年龄均影响腰椎间盘的ADC值,DTI的FA值和ADC值可以定量评估腰椎间盘及其退变程度,为早期腰椎间盘退变的临床诊断提供影像学依据。     

腰椎间盘的扩散张量成像观测及临床应用

目的　为腰椎间盘退变导致的腰腿痛等病症的临床诊断提供影像学依据。 方法　选取脊柱腰段扩散张量成像（DTI）扫描检查正常者200例和腰椎间盘退变者100例,在工作站划分腰椎间盘和腰椎间盘退变的感兴趣区,测量感兴趣区的表观扩散系数（ADC）和各向异性分数（FA）,比较不同解剖部位、年龄组腰椎间盘和不同Pfirrmann分级腰椎间盘退变的FA、ADC值。 结果　不同解剖部位腰椎间盘的FA值和ADC值均有统计学差异（P<0.05）,L1~2、L2~3、L3~4椎间盘的FA值逐渐降低,L4~5、L5~S1椎间盘的FA值则逐渐增高;L1~2、L2~3、L3~4椎间盘的ADC值逐渐增高,L3~4、L4~5、L5~S1椎间盘的ADC值则无明显变化。不同年龄组腰椎间盘的FA值无统计学差异（P>0.05）,ADC值有统计学差异（P<0.05）,随着年龄增长ADC值逐渐降低。不同Pfirrmann分级腰椎间盘退变的FA值和ADC值均有统计学差异（P<0.05）,随着Pfirrmann分级增高,FA值逐渐增高,ADC值逐渐降低。 结论　解剖部位、年龄均影响腰椎间盘的ADC值,DTI的FA值和ADC值可以定量评估腰椎间盘及其退变程度,为早期腰椎间盘退变的临床诊断提供影像学依据。     

正常成人颈椎间盘相关参数测量及意义

目的 提出椎间盘的测量方法并测量正常成人颈椎间盘相关参数,为设计人工颈椎间盘提供参数依据。 方法 从深圳市第二人民医院和深圳市南山医院提取正常成人颈椎MRI数据219例,测量C4/5、C5/6、C6/7 3个颈椎间盘的椎间盘前高,中高,后高,椎间角,矢径及横径6组数据并作统计学分析计算。 结果 颈椎间盘前高为（4.27±0.73）mm,中高为（5.63±0.83） mm,后高为（3.24±0.59）mm,颈椎间盘角度为（4.73±1.57）°,颈椎间盘矢径为（15.50±1.70）mm,横径为（22.20±2.56）mm。 结论 上述6组数据存在性别间的显著差异性和节段间的显著差异性,设计人工颈椎间盘应设计一系列不同参数的假体以满足不同性别不同颈椎节段的需求。     

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.     

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.     

兔腰椎间应用可注射型n-HA/Col骨材料融合效果的实验研究

目的观察可注射型纳米羟基磷灰石/胶原(n-HA/Col)复合骨材料在兔腰椎椎间缺损区的融合效果。方法新西兰大白兔16只,通过经腹腔腰椎前路手术建立L5/6、L6/7和L7/S1节段椎间缺损的实验模型,其中L5/6椎间缺损区不植入任何材料,作为空白阴性对照组;L6/7椎间缺损区植入可注射型纳米羟基磷灰石/胶原复合骨材料,作为实验组;L7/S1椎间缺损区植入固体型纳米羟基磷灰石/胶原复合骨材料,作为阳性对照组。所有的动物在术后当日均进行放射学检查,分别在术后4、8、12、16周4个时间点处死4只动物,获取腰椎标本,评估植入材料融合情况;行X线和CT扫描三维重建观察椎间融合形态;Masson染色结果应用Image-proplus 6.0软件计算不同区域骨组织与所在区域的比值,分析椎间融合组织结构。结果术后当日CT显示造模成功。术后4、8、12、16周影像学和组织学结果显示:随着时间延长,L6/7和L7/S1椎间成骨逐渐增强,两者成骨能力无明显差异(>0.05),而L5/6椎间未见明显的成骨影像。结论可注射型纳米羟基磷灰石/胶原复合材料在兔椎体间融合效果确切。     

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。     

单纯腰椎间盘突出与腰椎管狭窄症对腰椎曲度的影响

目的探讨单纯腰椎间盘突出与腰椎管狭窄症的影像学测量值间的差异及其相关性。方法对178例单纯腰椎间盘突出和162例腰椎管狭窄症患者经手术治疗后的X线、CT、MRI资料进行回顾性对照分析。测量腰椎曲线指数(LCI)、腰椎前凸度(Cobb角)、椎间盘突出指数(IDH)、硬膜囊横截面积(CSADS)、侧隐窝前后径(A-PDLR)(骨性标志),对所测量的数据进行统计学分析。结果腰椎间盘突出组,X线显示为腰椎生理曲度明显变小或消失,并多伴有侧弯;腰椎管狭窄组,X线显示为腰椎生理曲度明显加大,多不伴有侧弯,二者的差异具有显著性(P<0.01)。腰椎间盘突出程度与腰椎生理曲度呈负相关(r=-0.732,P<0.05);腰椎管狭窄程度与腰椎生理曲度呈正相关(r=0.605,P<0.05)。结论腰椎间盘突出和腰椎管狭窄症的腰椎生理曲线不同,突出和狭窄程度与腰椎生理曲线有相关性。