Changes in the surface of the superior articular joint from the lower thoracic to the upper lumbar vertebrae

Thirty-two human vertebral columns were selected from the Kanazawa Collection at the University of Kanazawa, Japan. The superior articular joint surface was categorised into the thoracic type and the lumbar type, and the pattern of the change from one type to the other in the lower thoracic and upper lumbar region was examined. In 21 of 32 cases (66%), the change from the thoracic to the lumbar type occurred over 2 vertebral segments, either between the 12th thoracic and 1st lumbar vertebrae (44%) or between the 11th and 12th thoracic vertebrae (22%). In the remaining 11 cases (34%), the change occurred over 3 vertebral segments, with a transitional type of articular surface. The change from the thoracic to lumbar type of articular surface has been believed to occur over 2 vertebral segments, but occurs over 3 segments in as many as 34% of the articular surfaces.     

Shape variation of the neural arch in the thoracic and lumbar spine: characterization and relationship with the vertebral body shape

Quantifying the human vertebral geometry is important for accurate medical procedures. We aimed to characterize the neural arch (NA) shape at T1-L5. All T1-L5 dry vertebrae (N = 4,080) of 240 individuals were measured and analyzed by age, gender, and ethnicity. A 3D digitizer was used to measure the dimensions of the spinous (SP) and transverse (TP) processes, vertebral canal (VC), laminae, and isthmus. Most parameters were independent of age and ethnicity, yet greater in males than in females. Isthmus length increases from T1 (9.8 mm) to T12 (19.87 mm) and decreases from T12 to L5 (9.68 mm) with right > left in the thorax and oppositely in the lumbar region. The SP is longer than its thickness both decreasing in the upper thorax (by ca. 4mm), increasing in the lower thoracic and upper lumbar vertebrae (by 7 mm for length and ca. 14.5 mm for thickness) and decreasing again along the lower lumbar vertebrae (both by 8 mm). The TP length decreases at T1-T12 (by 13 mm) and increases at L1-L5 with left > right at T1-L5 (P < 0.003). The laminar length decreases from T1 (8.72 mm) through T5 (4.76 mm) and increases toward L5 (8.4 mm) with right > left at T1-L5 (P < 0.003). The VC is oval-shaped at T1 and T11-L5 (width > length), rounded-shape at T2 and T10 (width = length), and inverted oval-shaped at T3-T9 (length > width). In conclusion, the NA is systematically asymmetrical and dynamic in shape along the thoracic and lumbar spine. The inter-relationship with the vertebral body and articular facets is discussed.     

Histological investigation of rabbit ligamentum flavum with special reference to differences in spinal levels

The structure of the ligamentum flavum has yet to be fully elucidated and no studies have investigated fine structural differences at different spinal levels in any animals. The aim of the present study was to clarify structural differences in the ligamentum flavum at different spinal levels (cervical: C3/4 and C5/6; upper thoracic: T2/3; lower thoracic: T9/10; lumbar: L3/4) using light and electron microscopy of rabbit specimens. Light microscopy using resorcin—fuchsin staining revealed that the distribution of elastic fibers was diffuse in the cervical and upper thoracic regions, but was generally dense in the lower thoracic and lumbar regions. Electron microscopy demonstrated that the cervical and upper thoracic regions were rich in collagen fibers. Conversely, the lower thoracic and lumbar regions were rich in elastic fibers. Quantitative image analyses displayed thick elastic fibers in the lower thoracic and lumbar regions, with high area ratios. Radiographic examinations revealed that ranges of motion were large at the cervical region, but small at the lower thoracic and lumbar regions. These findings suggest that structure of the ligamentum flavum varies at different spinal levels with respect to differences in motion.     

Activity of thoracic and lumbar epaxial extensors during postural responses in the cat

This study examined the role of trunk extensor muscles in the thoracic and lumbar regions during postural adjustments in the freely standing cat. The epaxial extensor muscles participate in the rapid postural responses evoked by horizontal translation of the support surface. The muscles segregate into two regional groups separated by a short transition zone, according to the spatial pattern of the electromyographic (EMG) responses. The upper thoracic muscles (T5-9) respond best to posteriorly directed translations, whereas the lumbar muscles (T13 to L7) respond best to anterior translations. The transition group muscles (T10-12) respond to almost all translations. Muscles group according to vertebral level rather than muscle species. The upper thoracic muscles change little in their response with changes in stance distance (fore-hindpaw separation) and may act to stabilize the intervertebral angles of the thoracic curvature. Activity in the lumbar muscles increases along with upward rotation of the pelvis (iliac crest) as stance distance decreases. Lumbar muscles appear to stabilize the pelvis with respect to the lumbar vertebrae (L7-sacral joint). The transition zone muscles display a change in spatial tuning with stance distance, responding to many directions of translation at short distances and focusing to respond best to contralateral translations at the long stance distance. Received: 2 January 1997 / Accepted: 23 September 1997     

椎弓根的解剖学观测与临床意义

目的 为临床脊柱手术提供形态学资料.方法 对36具成人尸体的整体脊柱标本,使用游标卡尺测量C_3～L_5椎弓根的高和宽.分别计算各节段椎弓根高和宽的均值和标准差,并分段计算颈椎(C_3～C_7)、胸椎、腰椎各段椎弓根高和宽的平均值.结果 C_3～C_7的高和宽分别为6.77mm和5.50mm;胸椎分别为12.30mm和6.37mm;腰椎平均值分别为15.97mm和9.41mm.结论 提供国人椎弓根的解剖学资料,为临床椎弓根螺钉内固定提供应用解剖学基础.     

Measuring movement at the low back

The clinical importance of movements of the human spine is increasingly being realized but their measurement is difficult to carry out. Traditionally, measurement of spinal motion focuses on the lumbar spine as the mobile region and movement at the lower thoracic spine is largely ignored. The aim of this study was to test the hypothesis that sagittal movement at the low back is not confined to the lumbar spine. The range of sagittal movement and the amount of skin distraction during trunk flexion was studied in 10 normal subjects. Angular movement in the sagittal plane between the vertebra prominens and S2 ranged between 40 degree and 83 degree among the subjects. Concomitant skin distraction showed that a mean of 32% (range 20-41%) of the movement between the upper thorax and sacropelvis occurred cranial to T12. We therefore suggest that the term "low back" should be applied to a series of mobile vertebrae in the lower thoracic and lumbar spines and that motion of this region in the sagittal plane should be considered as the movement of an immobile upper thoracic spine relative to the sacropelvis.     

Changes of contour of the spine caused by load carrying

The development of new leisure activities such as walking has spread the use of the backpack as a means of carrying loads. The aim of this work was to present a way of defining the movements imposed on the trunk by this type of load carrying. A 20 kg load situated at the thoracic level (T9) of the trunk, was placed in a backpack (2.5 kg). The 12 subjects were average mountain guides of Auvergne region, intermediate level and complete beginners. External markers were glued to the projecting contours of the spinous processes of the C7, T7, T12, L3 and S1 vertebrae, the shin and the external occipital tuberosity (EOT). Using a Vicon 140 3-D system we measured the effective mobility of the different spinal segments in the sagittal plane during one step. For every subject, we noticed a significant decrease of the effective inter-segmental mobility (EISM) between S1-L3-T12 (p < .01) while backpacking a 22.5 kg load. A decrease of EISM also appeared at the next level between L3-T12-T7 (p < .05). An increase of the EISM between T7-C7-EOT was noted (p < .05). We supposed that strength loss of the back muscles and/or angular oscillations of the trunk could be a common cause of symptoms during backpacking. The subjects using this type of load carrying have to adopt an adequate position of the lumbar, dorsal and cervical vertebrae.     

Differentiation and classification of thoracolumbar transitional vertebrae

The literature states that transitional vertebrae at any junction are characterized by features retained from two adjacent regions in the vertebral column. Currently, there is no published literature available that describes the prevalence or morphology of thoracolumbar transitional vertebrae (TLTV). The aim of this study was to identify the qualitative characteristics of transitional vertebrae at the thoracolumbar junction and establish a technique to differentiate the various subtypes that may be found. A selection of vertebral columns from skeletal remains (n = 35) were evaluated in this study. Vertebrae were taken based on features that are atypical for vertebrae in each relative region. The transitional vertebrae were qualitatively identified based on overlapping thoracic and lumbar features of vertebrae at the thoracolumbar junction. The following general overlapping characteristics were observed: aplasia or hypoplasia of the transverse process, irregular orientation on the superior articular process and atypical mammillary bodies. The results show that the most frequent location of the transitional vertebrae was in the thoracic region (f = 23). The second most frequent location was in the lumbar region (f = 10). In two specimens of the selection (f = 2), an additional 13th thoracic vertebra was present which functioned as a transitional vertebra. This study concluded that one can accurately identify the characteristics of transitional vertebrae at the thoracolumbar junction. In addition, the various subtypes can be differentiated according to the region in the vertebral column the vertebra is located in and the relative number of vertebral segments in the adjacent regions of the vertebral column. This provides a qualitative tool for researchers to differentiate the transitional vertebrae from distinctly different typical thoracic or lumbar vertebrae at the thoracolumbar junction.     

Distribution of preganglionic terminals in the cervical sympathetic ganglia detected by the expression of c-Fos like protein after electric stimulation of the ventral root

To determine the segmental relationship between the upper thoracic spinal cord and cervical sympathetic ganglia, we observed the distribution pattern of postganglionic cells which expressed c-Fos like protein, one of the products of immediate early genes, after electrical stimulation of ventral roots at the T1-T3 spinal segments. We recognized a clear segmental arrangement of postganglionic cells in the stellate ganglion along its rostrocaudal direction corresponding to the segmental arrangement of preganglionic neurons in the spinal cord. That is, postganglionic neurons which expressed c-Fos like protein after stimulation of the T1 ventral root were distributed in the middle region of the stellate ganglion in the rostrocaudal direction. The c-Fos like protein-positive neurons after stimulation of the T2 ventral root were distributed in a more caudal region of the stellate ganglion than after T1 ventral root stimulation. C-Fos like protein-positive neurons after stimulation of the T3 ventral root were mainly situated in a more caudal region of the stellate ganglion than after T2 ventral root stimulation. There was, however, no segmental relationship between the upper thoracic levels of the spinal cord and superior cervical ganglion in the rostrocaudal direction. These results indicate that the segmental innervation of the upper thoracic spinal cord exists in the stellate ganglion, but not in the superior cervical ganglion.     

Properties of utricular nerve-activated vestibulospinal neurons in cats

The axonal pathway, conduction velocities, and locations of the cell bodies of utricular nerve-activated vestibulospinal neurons were studied in decerebrated or anesthetized cats using the collision test of orthodromic and antidromic spikes. For orthodromic stimulation, bipolar tungsten electrodes were placed on the utricular nerve and the other vestibular nerve branches were transected. Monopolar tungsten electrodes were positioned on both sides of the upper cervical segments (C2–4), caudal end of the cervical enlargement (C7-T1), and from the lower thoracic to the upper lumbar segments (T12-L3) and were used for antidromic stimulation of the spinal cord. Another monopolar electrode was also placed in the oculomotor nucleus to study whether utricular nerve-activated vestibulospinal neurons have ascending branches to the oculomotor nucleus. Of the 173 vestibular neurons orthodromically activated by the stimulation of the utricular nerve, 46 were second-order vestibulospinal neurons and 5 were third-order neurons. The majority of the utricular nerve-activated vestibulospinal neurons were located in the rostral part of the descending vestibular nucleus and the caudal part of the ventral lateral nucleus. Seventy-three percent of the utricular nerve-activated vestibulospinal neurons descended through the ipsilateral lateral vestibulospinal tract. Approximately 80% of these neurons reached the cervicothoracic junction, but a few reached the upper lumbar spinal cord. Twenty-seven percent of the utricular nerve-activated vestibulospinal neurons descended through the medial vestibulospinal tract or the contralateral vestibulospinal tracts. Those axons terminated mainly in the upper cervical segments. Almost none of the utricular nerve-activated vestibular neurons had ascending branches to the oculomotor nucleus.     

Shape differences in the cervical and upper thoracic vertebrae in rats (Rattus norvegicus) and bats (Pteropus poiocephalus): can we see shape patterns derived from position in column and species membership?

The shapes of cervical (C1–C7) and upper thoracic (T1, T2) vertebrae from the rat and the grey-headed flying fox have been analysed by Fourier analysis to investigate the types of variation present and to try to isolate bones according to position along the vertebral column and species. It was found that the T2 vertebrae of the rat are very different from all others in the study, that C2 and C6 vertebrae are very similar and that the remaining vertebrae split according to species.     

Numerical variations in human vertebral column: a case report

Numerical increases in the elements of the vertebral column probably do not occur. In this case, 25 presacral vertebrae (PSV) were determined in the vertebral column of a 22-years-old male skeleton. Their distribution was as follows; 7 cervical, 12 thoracic, 1 thoraco-lumbar, 5 lumbar. Sacrum contained 5 vertebrae. In addition, sacralization or lumbarization was not seen.     

The vertebral level of origin of spinal nerves in the rat

Several dissections were performed to determine the level of spinal cord termination and the vertebral level at which the dorsal and ventral roots of spinal nerves C1-S4 emerged from the spinal cord in the rat. These levels of emergence were then compared to the level of exit from the vertebral canal. The dissections demonstrated that the effect of differential growth between spinal cord and vertebral column begins in the lower cervical region and becomes progressively more pronounced throughout thoracic and lumbar levels. The disparity between the vertebral level of emergence of spinal roots from the spinal cord and their level of exit via intervertebral foramina was found to be considerably larger than was previously reported by Greene ('68). It was further noted that the spinal cord terminated at the level of the intervertebral disc between the third and fourth lumbar vertebrae, not between the fourth and fifth lumbar vertebrae as reported by Greene ('68).     

Mechanism of change in the orientation of the articular process of the zygapophyseal joint at the thoracolumbar junction

The orientation of the superior articular processes in thoracic and lumbar vertebrae differs. The present study was undertaken to investigate the possible mechanism for the change from a posterolaterally facing superior articular surface in the thoracic region to a posteromedially facing curved articular surface in the lumbar region. The material of the study consisted of dry macerated bones of 44 adult human vertebral columns. The orientation of the superior articular process and its relation to the mamillary tubercle (process) was examined between T9 and L5 vertebrae in each column. An abrupt change from the thoracic to lumbar type of articular process was observed in 3 columns (7%). Forty-one (93%) columns showed a gradual change extending over either 2 or 3 successive vertebrae. The present study suggests that the change in the orientation of the superior articular process, from the coronal to the sagittal plane (sagittalisation), occurs due to the change in the direction of weight transmission through zygapophyseal joints at the thoracolumbar junction. It was observed that the gradual sagittalisation of the superior articular process in the transitional zone brought it close to the mamillary tubercle which eventually fused with it. Thus the study suggests that the characteristic posteromedially facing concave superior articular process of lumbar vertebrae may have formed because of the fusion of the articular process and the mamillary tubercle.     

The medial branch of the lateral branch of the posterior ramus of the spinal nerve

In the needle insertion of epidural anesthesia with the paramedian approach, the needle can pass through the longissimus muscle in the dorsum of the patients. When the needle touches a nerve in the muscles, the patients may experience pain in the back. Obviously, the needle should avoid the nerve tract. To provide better anesthetic service, analysis of the structure and where the concerned nerves lie in that region is inevitable. Material and method: We studied five cadavers in this study. Two cadavers were fixed with Thiel’s method. With these cadavers, we studied the nerve running of the posterior rami of the spinal nerve from the nerve root to the distal portion. Three of them were used for the study of transparent specimen, with which we studied the course and size of the nerve inside the longissimus muscle. Results: We observed there were three branches at the stem of the posterior rami of the spinal nerves between the body segment T3 and L5, i.e. medial branch, medial branch of the lateral branch and lateral branch of the lateral branch. The medial branch of the lateral branch supplied to the longissimus muscle. With the transparent specimen, we found that there were different nerve layouts between the upper thoracic, lower thoracic, upper lumbar, and lower lumbar segments in the medial branch of the lateral branch in the longissimus muscle. In the lower thoracic and upper lumbar segments, the medial branch of the lateral branch of the upper lumbar segments produced layers nerve network in the longissimus muscle. L1 and L2 nerves were large in size in the muscle. Conclusion: In the upper lumbar segments the medial branch of the lateral branch of the posterior rami of the spinal nerve produced dense network in the longissimus muscle, where the epidural needle has high possibility to touch the nerve. Anesthetists have to consider the existence of the medial branch of the lateral branch of the posterior rami of the spinal nerve when they insert the needle in the paramedical approach to the spinal column.     

大鼠脊髓损伤模型的解剖学参考定位

目的探查大鼠椎骨解剖学位置和形态特点,为制作大鼠脊髓损伤模型定位提供参考和解剖学依据。方法将20只Wistar大鼠按照体质量分成2组,每组10只。轻体质量组：120～150g;重体质量组：200-250g。对各组大鼠脊柱区进行解剖及椎骨位置、形态特点观察。结果大鼠颈椎7块,其中第2颈椎棘突突出最明显。胸椎13块,其中第2胸椎棘突突出最明显,并向上连结一膨大软骨;第9、10、11胸椎棘突之间距离最为靠近,且第9胸椎以上棘突倾向尾侧．第10胸椎棘突呈中立位,第11胸椎棘突以下方向倾向头侧。腰椎6块,第1腰椎棘突与脊柱两侧银白色腱膜第一个相交接处对应。结论依据脊柱两侧白色腱膜和椎骨棘突形态位置特点参考定位简单、精确,为大鼠脊髓损伤模型的制作提供了解剖学依据和有力保证。     

Three muscles in the upper costovertebral region: Description and clinical anatomy

The aim of the study was to describe three small muscles in the upper costovertebral region that have close proximity to the ventral rami of the lower cervical and upper two thoracic spinal nerves. The study was performed using both anterior and posterior approaches to the costovertebral region. Twenty‐five human cadavers, 15 males and 10 females with a mean age of 50 years and with normal spines, constituted the material of the study. Dissection revealed the presence of three triangular muscles that extended from the transverse processes of the seventh cervical through second thoracic vertebrae to the upper borders of the necks of the first through third ribs, respectively. The second and third muscles are described and reported for the first time. The ventral rami of the lower cervical and upper two thoracic spinal nerves emerged through narrow gaps between the described muscles and the bodies of seventh cervical and upper two thoracic vertebrae, respectively. The lateral branch of the dorsal ramus of the corresponding spinal nerve issued posteriorly between the muscle and the articular capsule of the zygapophyseal joint. It then curved round the posterior aspect of the muscle and passed through the gap between the muscle and the levator costarum, after supplying them both. We suggest that these three muscles were suggested to share a common embryogenesis with the intertransverse muscles. In addition, this study suggests that the three muscles described herein could be one of the potential causes of thoracic outlet syndrome. Clin. Anat. 22:352–357, 2009. © 2009 Wiley‐Liss, Inc.     

Network of the sympathetic nervous system: Focus on the input and output of the cervical sympathetic ganglion

Unlike the thoracic and lumbar sympathetic nervous systems with paravertebral ganglions in individual spinal segments, the cervical sympathetic nervous system lacks segmental structures corresponding to the spinal segments and only three ganglions, namely the upper and middle cervical ganglions and the stellate ganglion, are present. Single axons have been observed in the ganglions using an anterograde-labeling method to analyze their expansion in order to investigate the relationship between the cervical sympathetic ganglions and the spinal cord in rats. Although segmental structures were not confirmed in the upper cervical ganglion, segmental structures were demonstrated in the stellate ganglion. Next, it was determined that some sympathetic preganglionic neurons, nitric oxide synthetase-positive preganglionic neurons, form dense nerve endings on the upper cervical ganglion neurons that project onto organs closely related to glandular secretion in the head and neck region. Finally, the relationship between the cell body size of upper cervical ganglion neurons and the size of the target was investigated for the three major salivary glands in rats and it was determined that no direct relationship was present.     

退行性腰椎侧凸程度与骨质疏松症程度无关

背景：骨质疏松是以全身骨组织显微结构损坏及全身骨量减少为特征,有学者认为骨质疏松患者腰椎椎体前高不会减少,反而会有增加的趋势。 目的：分析退行性腰椎侧凸与骨质疏松症的相关性。 方法：选取退行性腰椎侧凸患者37例,另选取同期在住院治疗的腰椎非侧凸组患者37例。测量时采用改良Cobb法,沿患者的T12-L5各椎体上终板平行划线,2条线的最大夹角为侧凸角,两线所在椎体即为上、下端椎。运用双能X射线吸收法对患者L₂-L₄、股骨颈、Ward’s三角区以及股骨转子的骨密度进行测定。采用Linear regression对骨质疏松和退行性腰椎侧凸症的相关性进行分析 结果与结论：腰椎侧凸组患者L₂-L₄、股骨颈、Ward’s三角区以及股骨转子部位的骨密度T值与腰椎非侧凸组比较差异有显著性意义(P < 0.05),其中股骨各部位骨密度较腰椎(L₂-L₄)较低。腰椎侧凸组患者骨质疏松症发病率明显高于腰椎非侧凸组患者(P < 0.05)。Linear regression回归分析结果显示骨质疏松症是退行性腰椎侧凸发病的危险因素;退行性腰椎侧凸患者的腰椎及股骨近端各个部位的T值与侧凸Cobb’s角无明显相关性。结果提示,骨质疏松症是退行性腰椎侧凸发病的危险因素,同时骨质疏松程度与侧凸程度无关。     

Anatomical studies on the ovine spinal cord

The root attachment lengths were consistently greater in the cranial cervical (C3), midthoracic (T7), caudal lumbar (L5) and cranial sacral (S1) cord segment levels than the corresponding caudal cervical, caudal thoracic, cranial lumbar and caudal sacral levels respectively. As to the root emergence length the greatest values were obtained bilaterally at C3, T1, L4 and S1 cord segment levels respectively. The interroot intervals were maximum at C3, T13, L1 and S1 cord levels in the respective regions. The longest cord segments were located at C2, T13, L3 and S1 levels; the shortest were at C8, T1, L6, and S4 cord levels. The greatest diameter and cross-sectional area were confined to the last cervical, first 2 thoracic, last lumbar and first sacral cord segment levels. The spinal cord segments C2, T13, L4 and S1 were most voluminous in the respective regions. The topography of cord segments and the level of termination of the spinal cord have been studied and recorded.