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.     

3D Geometry and Quantitative Variation of the Cervico‐Thoracic Region in Crocodylia

This study aims to interpret the axial patterning of the crocodylian neck, and to find a potential taxonomic signal that corresponds to vertebral position. Morphological variation in the cervico‐thoracic vertebrae is compared in fifteen different crocodylian species using 3D geometric morphometric methods. Multivariate analysis indicated that the pattern of intracolumnar variation was a gradual change in shape of the vertebral series (at the parapophyses, diapophyses, prezygapohyses, and postzygapohyses), in the cervical (C3 to C9) and dorsal (D1‐D2) regions which was quite conservative among the crocodylians studied. In spite of this, we also found that intracolumnar shape variation allowed differentiation between two sub regions of the crocodylian neck. Growth is subtly correlated with vertebral shape variation, predicting changes in both the vertebral centrum and the neural spine. Interestingly, the allometric scaling for the pooled sample is equivalently shared by each vertebra studied. However, there were significant taxonomic differences, both in the average shape of the entire neck configuration (regional variation) and by shape variation at each vertebral position (positional variation) among the necks. The average neck vertebra of crocodylids is characterized by a relatively cranio‐caudally short neural arch, whereby the spine is relatively longer and pointed orthogonal to the frontal plane. Conversely, the average vertebra in alligatorids has cranio‐caudally longer neural spine and arch, with a relatively (dorso‐ventrally) shorter spine. At each vertebral position there are significant differences between alligatorids and crocodylids. We discuss that the delayed timing of neurocentral fusion in Alligatoridae possibly explains the observed taxonomic differences. Anat Rec, 297:1278–1291, 2014. © 2014 Wiley Periodicals, Inc.     

颈神经后支的解剖及其临床意义

目的为临床诊治椎孔外颈神经后支卡压提供解剖学基础。方法对20具(40侧)成人尸体的颈神经后支起源、走行、分支、分布及其与颈椎周围组织的解剖关系进行观测。结果C     

Regional changes in vertebra morphology during ontogeny reflect the life history of Atlantic cod (Gadus morhua L.)

This study examined vertebra formation, morphology, regional characters, and bending properties of the vertebral column of Atlantic cod throughout its life cycle (0–6 years). The first structure to form was the foremost neural arch, 21 days post hatching (dph), and the first vertebra centrum to form – as a chordacentrum – was the 3rd centrum at 28 dph. Thereafter, the notochord centra developed in a regular sequence towards the head and caudal fin. All vertebrae were formed within 50 dph. The vertebral column consisted of 52 (± 2) vertebrae (V) and could be divided into four distinct regions: (i) the cervical region (neck) (V1 and V2), characterized by short vertebra centra, prominent neural spines and absence of articulations with ribs; (ii) the abdominal region (trunk) (V3–V19), characterized by vertebrae with wing‐shaped transverse processes (parapophyses) that all articulate with a rib; (iii) the caudal region (tail) (V20–V40), where the vertebra centra have haemal arches with prominent haemal spines; (iv) the ural region (V41 to the last vertebra), characterized by broad neural and haemal spines, providing sites of origin for muscles inserting on the fin rays – lepidotrichs – of the tail fin. The number of vertebrae in the cervical, abdominal and caudal regions was found to be constant, whereas in the ural region, numbers varied from 12 to 15. Geometric modelling based on combination of vertebra lengths, diameters and intervertebral distances showed an even flexibility throughout the column, except in the ural region, where flexibility increased. Throughout ontogeny, the vertebra centra of the different regions followed distinct patterns of growth; the relative length of the vertebrae increased in the cervical and abdominal regions, and decreased in the caudal and ural regions with increasing age. This may reflect changes in swimming mode with age, and/or that the production of large volumes of gametes during sexual maturation requires a significant increase in abdominal cavity volume.     

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.     

经皮穿刺椎体后凸成形中骨水泥渗漏入椎管与胸腰椎椎体后壁形态的关系

背景:经皮穿刺椎体后凸成形术(percutaneous kyphoplasty,PKP)是治疗骨质疏松性椎体压缩骨折的有效方法,虽然临床效果满意,但骨水泥渗漏仍然为其主要并发症,既往文献报道骨水泥渗漏进入椎管的因素较多,但由于缺少对于胸、腰椎椎体后壁形态的观察,胸腰椎椎体后壁形态差异可能也是导致骨水泥渗漏进入椎管的重要因素之一。目的:探讨胸、腰椎椎体后壁形态对骨质疏松性椎体压缩骨折患者行PKP术骨水泥渗漏入椎管的影响。方法:选取行PKP术治疗的临床资料完整并同时具有T6-L5的CT平扫及三维重建影像资料的骨质疏松性椎体压缩骨折患者98例。采用CT三维重建及多平面重建技术测量非骨折椎体后壁凹入椎体的深度及相应椎体中矢状径,计算各椎体后壁凹入椎体深度占同一椎体中矢状径百分比。将测量椎体分为胸椎组(T6-T12)和腰椎组(L1-L5)进行比较观察。选择同期内行PKP手术治疗无CT三维重建资料的骨质疏松性椎体压缩骨折患者357例(548个椎体),也分为胸椎组和腰椎组观察比较骨水泥渗漏侵占椎管程度。结果与结论:①测量98例患者椎体后壁参数发现,椎体后壁凹入椎体深度在T6-T12逐渐加深,平均4.6 mm;L1-L5逐渐变浅,平均0.6mm,椎体后壁凹入椎体深度占同一椎体中矢状径百分比T6-T12均为16%(1/6);L1-L5平均为3%,腰椎较胸椎明显小于16%(1/6);②观察同期行PKP手术治疗的357例患者发现:胸椎行PKP术骨水泥脉渗漏入椎管渗漏率为10.2%(31/304),腰椎渗漏率为3.7%(9/244)。胸椎组骨水泥渗漏侵占椎管最大矢状径平均为(3.1±0.2)mm,侵占椎管面积平均为(30.8±0.3)mm2,椎管侵占率为(22.5±0.2)%;腰椎组骨水泥渗漏侵占椎管最大矢状径为(1.4±0.1)mm,侵占椎管面积为(14.9±0.2)mm2,椎管侵占率为(11.4±0.3)%,胸椎组骨水泥渗漏发生率、侵占椎管最大矢状径、面积明显大于腰椎组(P<0.05)。③结果证实,中下胸椎行PKP术应尽量避免骨水泥分布达到椎体后16%(1/6),因中下胸椎、腰椎椎体后壁凹入椎体深度差异会对PKP术骨水泥渗漏进入椎管的观察造成影响,可能是导致中下胸椎椎管内骨水泥渗漏率明显高于腰椎的原因之一。该试验获得西南医科大学附属医院伦理委员会批准(批准号:K2018008)。     

Morphology of the lumbar spinal canal in normal adult Turks

Pathological changes can occur in the diameters of the lumbar spinal canal. Therefore, assessing the canal size an important diagnostic procedure. Two hundred plain anterioposterior radiographs of the lumbar spine were examined. The sample consisted of 100 males and 100 females. The transverse diameter of the bony spinal canal (interpedicular distance), which was measured as the minimum distance between the medial surfaces of the pedicles of a given vertebra, was measured. In addition, the transverse diameter of the vertebral body, which was measured as the minimum distance across the waist of the vertebra, was measured. The distances were measured to the nearest one tenth of a millimetere using a Vernier caliper. At all levels (L1 - L5) the transverse diameters of the lumbar spinal canal were approximately 1 - 1.5 mm higher in males than in females. The intersegmental differences increased proximodistally, in both sexes. The ratio of the transverse diameter canal to the width of the vertebra ranged from 0.55 to 0.60 mm in both sexes. The distribution of the different lumbar canal types were 47% A, 42% B, 11% C. Additionally, subtypes were determined and classified.     

Posterolateral tunnels and ponticuli in human atlas vertebrae

The posterolateral tunnel on the superior surface of the first cervical (atlas) vertebra is of normal occurrence in monkeys and other lower animals, but its presence in the form of a tunnel-like canal, for the passage of the third part of the vertebral artery over the posterior arch of the human atlas vertebra is not reported. The aim of the present study was to detect the presence of such a canal, in addition to other types of ponticuli (little bridges) reported by earlier investigators, in macerated atlas vertebrae and routine cadaveric dissections. The posterolateral tunnel was detected in 1.14%, and the posterior and lateral ponticuli in 6.57 and 2% of vertebrae. Probably the bony roof of the posterolateral tunnel serves the purpose of additional lateral extension for the attachment of the posterior atlanto-occipital membrane in quadrupeds, where the load of the head is supported by the extensor muscles of the neck, ligaments and posterior atlanto-occipital membrane. In man, where the weight of the head is borne by the vertical loading of the superior articular process of the atlas, the roof of the tunnel has disappeared.     

Analysis of dural sac thickness in the human cervical spine

The thickness of the dura mater in the human cervical spine can vary between individuals and by vertebral level; these differences can result in various clinical outcomes. The purpose was to measure and analyze cervical dura mater thickness. Microscopic measurements were made of tissue from human cadavers. The subjects were nine human cadavers with no previous history of spinal deformity or surgery. Fourteen segments of both anterior and posterior dura mater from the C1 to C7 cervical vertebrae were obtained. Dura mater thickness was measured using an infrared laser-based confocal microscope. Statistical analyses were performed to examine the relationships of cervical dura mater thickness with vertebral level, age, and sex. The overall average cervical dura mater thickness was 379.3 × 10^?3 mm. Statistically significant differences in thickness were found between the anterior and posterior segments (P < 0.0001). Moreover, the thickness at each vertebral level was significantly different from the thicknesses at the other levels (P < 0.05). The posterior dura mater thickness was highest at C1 and lowest at C5/6. Posterior dura mater thickness was significantly different at the axial, sub-axial, and lower cervical levels, whereas anterior dura mater thickness was relatively constant among levels. A significant correlation was found between thickness and age (P < 0.05); however, the average dura mater thickness was not significantly different between males and females. This study shows anatomical differences in cervical dura mater thickness with respect to vertebral level and age. These results provide anatomical information that will inform basic research and clinical approaches.     

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。     

The orientation of the articular facets of the zygapophyseal joints at the cervical and upper thoracic region

Knowledge of the orientation of facet joints in the cervical and upper thoracic region is important for understanding the biomechanical properties and clinical conditions relevant to the neck. The study was undertaken on dry macerated bones from 30 adult male human vertebral columns. The orientation of the superior articular facets in relation to their inclination with the sagittal and transverse planes was examined between C3 and T3 vertebrae in each column. The linear dimensions of the superior articular facets and the width/height ratio were also calculated. The results show that all vertebrae at C3 level and 73% at C4 level displayed posteromedially facing superior articular facets. Similarly at T1 level (C7/T1 joint) and below, all columns showed posterolaterally facing superior articular facets. The level of change in orientation, from posteromedial to posterolateral facing superior facets, was not constant and occurred anywhere between C4 (C3/C4 joint) and T1 (C7/T1 joint). The change in orientation followed 2 different patterns, i.e. sudden or gradual. The C6 vertebra (C5/C6 joint) was the most frequent site to show the transition. The shape of the superior articular facets was circular to oval at C3, C4 and C5 levels and gradually changed to a transversely elongated surface at C7 and T1. These findings correlate well with various cervical movements and associated clinical conditions.     

下颈椎观测对颈椎前路手术的意义

目的为下颈椎前方入路提供应用解剖学基础。方法测量广东地区出土成人干燥下颈椎(C3～C7)标本40套。测量项目包括椎体的前高、中高、后高、上矢径、中矢径、下矢径、上横径、中横径、下横径以及钩突间距。结果下颈椎椎体上横径平均为19.2mm,中横径21.1mm,下横径22.2mm;椎体上矢径平均为15.3mm,中矢径14.9mm,下矢径16.1mm。结论本文的测量数据为改进下颈椎前路手术及减少手术并发症提供了解剖学依据。     

Development of an equation for calculating vertebral shear failure tolerance without destructive mechanical testing using iterative linear regression

Equations used to determine vertebral failure tolerances without the need for destructive testing are useful for scaling applied sub-maximal forces during in vitro repetitive loading studies. However, existing equations that use vertebral bone density and morphology for calculating compressive failure tolerance are unsuitable for calculating vertebral shear failure tolerance since the primary site of failure is the pars interarticularis and not the vertebral body. Therefore, this investigation developed new equations for non-destructively determining vertebral shear failure tolerance from morphological and/or bone density measures. Shear failure was induced in 40 porcine cervical vertebral joints (20 C3-C4 and 20 C5-C6) by applying a constant posterior displacement to the caudal vertebra at 0.15 mm/s. Prior to destructive testing, morphology and bone density of the posterior elements were made with digital calipers, X-rays, and peripheral quantitative computed tomography. Iterative linear regression identified mathematical relationships between shear failure tolerance, and morphological and bone density measurements. Along with vertebral level, pars interarticularis length and lamina height from the cranial vertebra, and inferior facet height from the caudal vertebra collectively explained 61.8% of shear failure tolerance variance. Accuracy for this relationship, estimated using the same group of specimens, was 211.9 N or 9.8% of the measured shear failure tolerance.     

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。     

The incidence of the lateral bridge of the atlas vertebra

The vertebral artery, in its course from the subclavian artery to the basilar artery, is vulnerable to damage or distortion from external factors such as bony, ligamentous or muscular structures (Mehalic & Farhat, 1974; Parkin et al. 1978; Schellhas et al. 1980; Braun et al. 1983; Dunne et al. 1987; Fast et al. 1987). In the atlas vertebra, the retroarticular canal and the lateral bridge are examples of bony outgrowth or exostosis which may cause external pressure on the vertebral artery as it passes from the foramen transversarium of the vertebra to the foramen magnum of the skull. If this pressure is severe enough, as may occur during the extreme rotatory movements carried out during therapeutic manipulation of the cervical spine, the vertebral artery may be compressed (Lamberty & Zivanovich, 1973), reducing its cross-sectional area, and compromising its blood flow (Taitz & Nathan, 1986). Vertebrobasilar ischaemia from compression of the vertebral arteries by osteophytes is an uncommon occurrence under normal circumstances (Warlow, 1996). There are few studies of the lateral bridge of the atlas reported in the literature (MacAlister, 1869, 1893; Lamberty & Zivanovic, 1973; Saunders & Popovich, 1978; Taitz & Nathan, 1986). The lateral bridge was first described by MacAlister (1869, 1893) as a variety of the ‘posterior glenoid process’ (the retroarticular canal), which he termed the ‘gleno-transverse bony arch’. As its name implies, it is a lateral outgrowth of bone from the superior articular facet or lateral mass to the posterior root of the transverse process of the atlas (MacAlister, 1869, 1893; Lamberty & Zivanovic, 1973; Saunders & Popovich, 1978; Taitz & Nathan, 1986). The retroarticular canal is formed by an exostosis passing from the posterior surface of the lateral mass to the posterior margin of the vertebral artery groove of the atlas. Thus the lateral bridge forms another arch, secondary to the retroarticular canal, through which the vertebral artery must pass (MacAlister, 1869).     

Effects of Advanced Age on the Morphometry and Degenerative State of the Cervical Spine in a Rat Model

Aging causes changes in the geometry of the human cervical spine that may influence the tissue response to applied loads. Rat models are often used to study spinal cord injuries (SCI) and have the potential to enhance our understanding of the effect of age on SCI. The goal of this study was to characterize the morphometry and degenerative state of the cervical spine in Fisher 344 rats, and to determine the influence of age on these variables. Fifteen rats were split into three age groups: young adult (3 months of age), aged (12–18 months) and geriatric (30 months). Following tissue harvest we used a μCT scanner to image the cervical and upper thoracic spine from each specimen. Analysis software was used to measure variables including canal pinch diameter (the most rostral point on the dorsal aspect of a vertebral body to the most caudal aspect of the lamina on the immediately rostral vertebra), vertebral canal depth, width, and area, vertebral body height, depth, width, and area, and intervertebral disc thickness. Orthopaedic surgeons used midsagittal images to rate the degenerative state of the intervertebral discs. For all measures except disc thickness there was a significant increase (mean (SD) = 15.0 (9.7)%) for the aged compared to young specimens (P < 0.05). There were significant differences between the aged and geriatric specimens for only vertebral body depth (P = 0.016) and area (P = 0.020). Intervertebral disc degeneration was significantly greater on the ventral aspect of the spinal column (P < 0.001), with a trend toward increased degeneration in the geriatric specimens (P = 0.069). The results suggest that age‐related morphometric differences may need to be accounted for in experimental aging models of SCI in rats. Anat Rec, 2011. © 2011 Wiley‐Liss, Inc.     

纳米人工椎板在脊柱椎板缺损修复中的临床应用

目的探讨纳米羟基磷灰石/聚酰胺66﹙n-HA/PA66﹚人工椎板在脊柱切除全椎板的临床应用,防止硬脊膜粘连受压,修补椎板缺损,后路融合稳定脊柱,形成椎管的作用.方法30例脊柱疾病患者外科手术中均应用人工椎板﹙n-HA∕PA66﹚治疗,修复于肿瘤、椎管狭窄、椎体滑脱,脊柱骨折,颈椎病伴发育性椎管狭窄、后纵韧带骨化等切除全椎板患者术中所致成的椎板缺损.结果30例术后切口均I期愈合,随访6~18个月,患者症状不同程度改善.X 线片及 CT 片示人工椎板与骨接触面界限消失,融合良好.结论纳米人工推板修复缺损的椎板,融合完成椎管成形,稳定了脊柱后柱,防止脊膜暴露后的并发症,并具有人体椎板的生物力学性能和广泛的实用性.     

Can the transverse foramen/vertebral artery ratio of double transverse foramen subjects be a risk for vertebrobasilar transient ischemic attacks?

The C6 is the cervical vertebra into which the vertebral artery enters the passage of the transverse foramen and it is the vertebra most affected by double transverse foramina. There is currently little information about the relation between the vertebral artery and the double transverse foramen in C6. We aimed to test whether subjects with a double transverse foramen in C6 have a reduced transverse foramen/vertebral artery ratio when compared with normal anatomy subjects who possess a single transverse foramen which may be a risk for transient vertebral artery stenosis. We measured the area of the transverse foramen and the vertebral artery in 27 double transverse and 56 normal anatomy subjects using computed tomography angiography. We found significant differences in the area of the transverse foramen between double transverse and normal subjects (P < 0.001) but not between the vertebral artery area of double transverse and normal subjects (P = 0.829). The subjects with double transverse foramina have a reduced transverse foramen/vertebral artery ratio, which may be a possible risk for transient vertebral artery stenosis.     

Evaluation of effectiveness of a facet wiring technique: Anin vitro biomechanical investigation

The effects of facet wiring procedure commonly used for stabilizing cervical spines after laminectomy or bilateral facet dislocation on the motion behavior of whole cervical spines are investigated using a Selspot II^® system. A fresh human ligamentous intact specimen was potted at T1/T2 vertebra and clinically relevant loads applied to the topmost vertebra (C2) of the specimen. The resulting three rotational components of each of the five vertebral bodies (C3-C7) were recorded. Specimen was injured to mimic total laminectomies at C5 and C6 vertebral levels and tested again. The injured specimen was stabilized, using a facet wiring construct, across C4-C7 segment before testing for the final time. The injured specimens, compared to the intact specimens, demonstrated an increase in flexion-extension of about 10%. Facet wiring imparted stability to the cervical spine by stiffening segments up to roughly four times intact values.