C7 vertebra homeotic transformation in domestic dogs – are Pug dogs breaking mammalian evolutionary constraints?

The number of cervical vertebrae in mammals is almost constant at seven, regardless of their neck length, implying that there is selection against variation in this number. Homebox (Hox) genes are involved in this evolutionary mammalian conservation, and homeotic transformation of cervical into thoracic vertebrae (cervical ribs) is a common phenotypic abnormality when Hox gene expression is altered. This relatively benign phenotypic change can be associated with fatal traits in humans. Mutations in genes upstream of Hox, inbreeding and stressors during organogenesis can also cause cervical ribs. The aim of this study was to describe the prevalence of cervical ribs in a large group of domestic dogs of different breeds, and explore a possible relation with other congenital vertebral malformations (CVMs) in the breed with the highest prevalence of cervical ribs. By phenotyping we hoped to give clues as to the underlying genetic causes. Twenty computed tomography studies from at least two breeds belonging to each of the nine groups recognized by the Federation Cynologique Internationale, including all the brachycephalic ‘screw‐tailed’ breeds that are known to be overrepresented for CVMs, were reviewed. The Pug dog was more affected by cervical ribs than any other breed (46%; P < 0.001), and was selected for further analysis. No association was found between the presence of cervical ribs and vertebral body formation defect, bifid spinous process, caudal articular process hypoplasia/aplasia and an abnormal sacrum, which may infer they have a different aetiopathogenesis. However, Pug dogs with cervical ribs were more likely to have a transitional thoraco‐lumbar vertebra (P = 0.041) and a pre‐sacral vertebral count of 26 (P < 0.001). Higher C7/T1 dorsal spinous processes ratios were associated with the presence of cervical ribs (P < 0.001), supporting this is a true homeotic transformation. Relaxation of the stabilizing selection has likely occurred, and the Pug dog appears to be a good naturally occurring model to further investigate the aetiology of cervical ribs, other congenital vertebral anomalies and numerical alterations.     

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。     

Morphology of the articular processes of the sixth cervical vertebra in humans

With the exception of the 7th vertebra, both past and recent literature describe the lower cervical vertebrae as possessing similar morphological characteristics (Soemmering, 1794; Cruveilhier, 1862; Luschka, 1862; Henle, 1871; Braus-Elze, 1954; Romanes, 1981; Williams et al. 1989; Benninghof, 1994). Gross anatomical differences from the 3rd to the 7th cervical vertebrae comprise the shapes of the vertebral body and uncinate and spinous processes (Putz, 1976; Penning, 1988; Lang, 1990) and the more developed anterior tubercle and anterior root of the transverse process of the 6th cervical vertebra (C6) (Paturet, 1951). During routine examination of a series of dried skeletons, the articular processes (AP) of C6 were found to be distinct from the rest of the cervical vertebrae. The aim of this study was to confirm this unusual appearance of the C6 process by inspecting a sample of dried skeletons. We report the morphology of the AP of C6 in 76 well preserved complete adult skeletons (58 males, 18 females; age 31–77 y) and 5 young specimens from the Anatomical Institutes of Alicante, Valencia and Murcia (Spain) and Munich (Germany). Another 12 skeletons were excluded from the study due to arthritic changes in their cervical APs.     

以循证医学的理念观察颈椎综合征的MRI图像

目的鉴于MRI对组织的高分辨性能,利用该图像观察颈椎综合征患者的椎管外组织的病理状况.方法54例患者,其中男30例,女24例,分为2组.观察组44例颈椎综合征患者,对照组10例颈部外伤和三叉神经痛患者.通过常规的MRI矢状位及横轴位颈椎图像,比较两组软组织增生情况.结果与结论在颈椎综合征MRI的颈椎及上段胸椎棘突后侧,均可观察到不同程度的慢性纤维性变化,与对照组比较,有可比性.提示临床上颈椎综合征多与颈肩区筋膜炎、棘突炎相关,属于无菌性炎症,其慢性阶段,局部发生了纤维增生性改变.建议在观察分析此种病症的颈椎骨质及椎间盘改变的同时,宜重视棘突后侧的纤维性变化,有利于病理病因的研究.     

Sexual dimorphism of the posterior cervical spine muscle attachments

Cervical spinal injury and neck pain are common disorders with wide physical implications. Neck pain and disability are reported to occur in females more often than in males, and chronic or persistent neck pain after whiplash is twice as common in females. Female athletes also sustain a higher percentage of concussions compared to male athletes. Still, while sexual differences in clinical presentation and outcome are well-established, the underlying etiology for the disparity remains less clear. It is well-established that the origin and insertion landmarks of posterior neck muscles are highly variable, but we do not know if these interindividual differences are associated with sex. Expanding our knowledge on sexual dimorphism in the anatomy of the cervical muscles is essential to our understanding of the possible biomechanical differences between the sexes and hence improves our understanding as to why females suffer from cervical pain more than males. It is also of paramount importance for accurate planning of posterior cervical spine surgery, which cuts through the posterior cervical musculature. Therefore, our main objective is to characterize the anatomy of posterior neck musculature and to explore possible sexual differences in the location of their attachment points. Meticulous posterior neck dissection was performed on 35 cadavers, 19 females, and 16 males. In each specimen, 8 muscle groups were examined bilaterally at 45 osseous anatomical landmarks. Muscles and their attachment sites were evaluated manually then photographed and recorded using Microscribe Digitizer technology built into 3D models. A comparison of attachment landmarks between males and females for each muscle was conducted. Out of the eight muscles that were measured, only two muscles demonstrated significant sex-related anatomical differences—Spinotranversales (splenius capitis and cervicis) and Multifidus. Male Spinotransversales muscle has more attachment points than female. It showed more cranial insertion points in the upper cervical attachments (superior nuchal line, C₁ posterior tubercle, and mastoid process) and more caudal insertion points in the spinous processes and transverse processes of the lower cervical and upper thoracic vertebrae. Thus, the male subjects in this study exhibited a greater coverage of the posterior neck both cranially and caudally. Female Multifidus has more attachment points on the spinous processes and articular processes at middle and lower cervical vertebrae and at the transverse processes of the upper thoracic vertebrae. All remaining muscles exhibited no sexual differences. Our findings highlight, for the first time, a sexual dimorphism in attachment points of posterior cervical musculature. It reinforces the notion that the female neck is not a scaled version of the male neck. These differences in muscle attachment could partially explain differences in muscle torque production and range of motion and thus biomechanical differences in cervical spine stabilization between sexes. It sheds a much-needed light on the reason for higher whiplash rates, concussion, and chronic cervical pain among females. Surgeons should take these sexual morphological differences into consideration when deliberating the best surgical approach for posterior cervical surgery.     

An unusual foramen in the transverse process of first thoracic vertebra

The presence of foramina in the transverse processes of thoracic vertebrae is not a common feature while they are the characteristic feature of cervical vertebrae. Foramina present in the transverse process of cervical vertebrae give passage to the vertebral artery—an important artery supplying the brain and spinal cord. Thoracic vertebrae typically bear facets on the body and the transverse processes for articulation with ribs. We report the presence of a complete foramen in the left transverse process of first thoracic vertebra, which is a very rare finding. The foramen was present near the root of the transverse process in alignment with the foramina transversaria of the cervical vertebrae of the same side. This variation is explained embryologically in relation to the branches of dorsal aortae in post-branchial stage of development. Knowledge of such a variation may be of great relevance for accurate interpretation of radiological pictures and for CT and MR angiographies as well as for the management of surgical procedures.     

Double Foramen Transversarium in Cervical Vertebra an Osteological Study

50 sets of typical dried cervical vertebrae of human were studied for no. of foramen transversarium present on each transverse process of vertebra. So double foramen transversarium were detected unilaterally or bilaterally in 16 vertebrae out of 200 typical (C3-C6) cervical vertebrae. The variation of foramina appears to follow a pattern at various vertebral level.The course of vertebral artery may be distorted under such conditions. The normal factor responsible for such anomalies of foramen transversarium is developmental or related to the variation of course of vertebral artery.     

颈椎棘突骨折累及后方韧带复合体损伤对羊颈椎生物力学稳定性的影响

目的通过体外羊标本模拟颈椎棘突骨折累及后方韧带复合体(posterior ligamentous complex,PLC)损伤对颈椎生物力学稳定性的影响,探讨颈椎后方结构在维持颈椎稳定性中的作用。方法将新鲜羊颈椎C3~6标本24具随机平均分为3组:正常对照组(A组);单纯颈椎棘突骨折组(B组);颈椎棘突骨折合并PLC损伤组(C组)。在1.5 N·m力矩加载下,分别测量各组在前屈、后伸、左右侧弯和左右旋转6种工况下颈椎活动度(range of motion,ROM),使用单因素方差分析比较3组之间的ROM差异。结果单纯颈椎棘突骨折对羊颈椎稳定性影响不大,各工况下ROM同正常对照组比较差异无统计学意义(P0.05);颈椎棘突骨折合并PLC损伤组在前屈、后伸及左右旋转工况下ROM显著增加,同正常对照组相比,差异具有统计学意义(P0.05),颈椎棘突骨折合并PLC损伤组在左右侧弯工况下同正常对照组比较ROM变化不显著,差异无统计学意义(P0.05)。结论单纯颈椎棘突骨折本身并不影响颈椎整体稳定性,但颈椎棘突骨折伴有PLC损伤时可造成颈椎不稳,需要手术干预。     

腰椎棘突中轴线与椎弓根进钉通道三维关系研究

目的　探讨腰椎棘突中轴线与椎弓根进钉通道的三维位置关系,为腰椎内固定和辅助固定技术及临床应用提供个性化、精准化的解剖学数据参考。 方法　将CT数据通过三维重建和逆向工程软件处理,测量椎体70%和90%边界深度的椎弓根进钉通道所在轴线L和棘突中轴线M与三维参考平面夹角,以及交点与线及三维参考平面距离。 结果 （1）腰椎棘突中轴线与矢状面、水平面、冠状面夹角分别为2º ~3º、11º ~18º、71º ~77º;椎体70%和90%边界深度的椎弓根进钉通道与矢状面夹角分别为7º ~22º和 16º ~33º,与水平面夹角分别为1.8º ~2.9º和1.4º ~2.4º,与冠状面夹角分别为67º ~82º和56º ~73º;（2）随腰椎水平降低,点到线的距离呈规律性变化;（3）随腰椎水平降低,点到三个平面的距离也呈规律性变化。 结论 通过对腰椎棘突中轴线与70%和90%边界深度的椎弓根进钉通道的三维关系分析,为临床经皮椎弓根螺钉置入手术和相关器械设计提供数据参考。     

Mandibulo-acral dysplasia: Indian patient with severe bony changes

We report an Indian patient with mandibulo-acral dysplasia. This patient had absence of spinous processes of 4th and 5th cervical vertebrae and very severe bony changes but no loss of teeth.     

Morphometry of the kangaroo spine and its comparison with human spinal data

The upright posture of the kangaroo suggests that the spine of the kangaroo could be a possible substitute model for biomechanical studies of the human spine. A prerequisite for this should be the agreement of anatomy in humans and kangaroos. The purpose of this study was to investigate the anatomical parameters of the kangaroo spine from C4 to S4 and compare them with existing anatomical data of the human spine. Eight complete spines of the red giant kangaroo were obtained and 21 anatomical parameters were measured from the vertebral bodies, spinal canal, endplate, pedicles, intervertebral discs, transverse, and spinous processes. Most similarities between kangaroo and human spines were found for the vertebral bodies in the cervical and the lumbar spine. The largest differences were evident for the spinous processes. Although both species are somehow upright, these differences may be explained by the way how they move. Jumping probably requires more muscle strength than walking on two legs.     

Cervical vertebral body growth and emergence of sexual dimorphism: a developmental study using computed tomography

The size and shape of human cervical vertebral bodies serve as a reference for measurement or treatment planning in multiple disciplines. It is therefore necessary to understand thoroughly the developmental changes in the cervical vertebrae in relation to the changing biomechanical demands on the neck during the first two decades of life. To delineate sex‐specific changes in human cervical vertebral bodies, 23 landmarks were placed in the midsagittal plane to define the boundaries of C2 to C7 in 123 (73 M; 50 F) computed tomography scans from individuals, ages 6 months to 19 years. Size was calculated as the geometric area, from which sex‐specific growth trend, rate, and type for each vertebral body were determined, as well as length measures of local deformation‐based morphometry vectors from the centroid to each landmark. Additionally, for each of the four pubertal‐staged age cohorts, sex‐specific vertebral body wireframes were superimposed using generalized Procrustes analysis to determine sex‐specific changes in form (size and shape) and shape alone. Our findings reveal that C2 was unique in achieving more of its adult size by 5 years, particularly in females. In contrast, C3–C7 had a second period of accelerated growth during puberty. The vertebrae of males and females were significantly different in size, particularly after puberty, when males had larger cervical vertebral bodies. Male growth outpaced female growth around age 10 years and persisted until around age 19–20 years, whereas females completed growth earlier, around age 17–18 years. The greatest shape differences between males and females occurred during puberty. Both sexes had similar growth in the superoinferior height, but males also displayed more growth in anteroposterior depth. Such prominent sex differences in size, shape, and form are likely the result of differences in growth rate and growth duration. Female vertebrae are thus not simply smaller versions of the male vertebrae. Additional research is needed to further quantify growth and help improve age‐ and sex‐specific guidance in clinical practice.     

下颈椎棘突及棘突间隙影像解剖及其临床意义

目的　测量下颈椎棘突及棘突间的解剖参数,为试制颈椎棘突间非融合固定装置提供解剖学依据。 方法　收集46名（男性22人,女性24人）进行颈椎CT扫描的志愿者,将扫描信息传至GE AW4.4工作站测量棘突长度、宽度、高度、倾斜角度以及相邻棘突间距。并做统计学分析。 结果　男女存在显著差异,男性下颈椎棘突：C7最长,C3最短;C7最宽,C5最薄;C7最高,C5最矮;C6倾斜角度最大,C3最小;C3/C4棘突间距最大,C6/C7最小。女性下颈椎棘突：C7最长,C3最短;C7最宽,C4最薄;C7最高,C3最矮;C7倾斜角度最大,C3最小;C3/C4棘突间距最大,C6/C7最小。 结论　本研究较全面地测量了下颈椎棘突的相关指标,包括棘突长度、宽度、高度、倾斜角度以及相邻棘突间距,为试制颈椎棘突间非融合固定装置提供了一定的数据支持和指导意义。     

C7棘突的体表定位观测及其临床意义

目的　研究健康成年人C7棘突体表触诊定位的准确性,探讨其原因及临床意义。 方法　选取健康成年志愿者500名（男性354名、女性146名）,由3名骨科主治医师应用触诊法,对其进行C7棘突的体表定位并用铝片标记,再拍摄颈椎正侧位X线片,然后观察C7棘突的体表触诊定位准确率。同时,通过X线、CT三维重建测量C6、C7、T1棘突的长度,并对测量结果进行分析。 结果　98.8%（494名）的被检者能通过体表触诊准确定位C7,1.2%（6名,均为男性）的被检者体表触诊定位于C6。在X线中,C6的棘突长度为(2.97±0.11) cm,C7为(3.16±0.16) cm,T1为(3.20±0.15) cm;在CT三维重建中,C6的棘突长度为(2.98±0.12) cm,C7为(3.18±0.17) cm,T1为(3.50±0.16) cm。无论是X线还是CT三维重建,三个椎体棘突长度都具有统计学差异（P<0.01）,但两种影像学检查手段所测得的C6、C7、T1棘突长度不具有统计学差异（P>0.05）。 结论　C7棘突的体表触诊定位方法受到多种因素的影响,可能存在一定的误差。临床可利用颈椎X线、CT等辅助方法确保其诊治的准确性、安全性。     

颈椎阻滞椎X线表现及特征

目的　探讨颈椎阻滞椎的X线表现及特征。 方法　回顾性分析125例颈椎阻滞椎X线资料,男性45例,女性80例,年龄24~75岁,平均年龄41.9岁,男女比例为1:1.77。分析其阻滞椎的发生节数、融合部位、骨赘发生、颈椎前凸曲度以及上、下椎间隙等情况。 结果　本组病例中阻滞椎累及2个椎体100例,累及3个椎体5例,累及4个椎体17例,累及5个椎体3例。单节段阻滞椎以C2~3最多,共43例（43%）;其次是C3~4,共16例（16%）。融合部位：椎体及附件的同时融合82例（65.6%）,单纯椎体融合28例（22.4%）。颈椎曲度变直或反张36例（28.8%）。椎体前/后缘骨赘110例（88%）;上椎间隙狭窄7例（5.6%）;下椎间隙狭窄15例（11.7%）;棘突融合52例（41.6%）;前纵韧带钙化19例（15.2%）;项韧带钙化17例（13.6%）;颅底凹陷症15例（12%）。 结论　颈椎阻滞椎常表现为单节段的融合,椎体及附件的同时融合比单纯椎体融合多见。阻滞椎常伴有邻近节段的退行性改变及颅底凹陷。     

腰椎棘突间区的影像解剖学研究及其临床意义

目的：探讨三维CT重建腰椎棘突间区的方法及其临床意义。方法：GE light speed 16 pro螺旋CT扫描患者46人，扫描条件为层厚0．625mm，层距0．3mm，在图像工作站中ADW4．2软件采用容积再现及多平面重建技术重建T12至S1段脊柱三维图像，对图像进行整倍数放大，并使用图像工作站（Advantage Workstation）软件中的测量工具，对棘突间距，棘突顶距，棘突中央高度，相邻棘突上下缘及中央厚度进行测量，测量过程中可以对腰椎三维图像任意角度旋转，选择最佳测量图像，对测量的图像数据进行正态性检验、t检验。结果：腰椎棘突间距从上到下（L1～5）逐渐减小，L1～2为8．26mm，L4～5，为5．66mm。棘突顶距棘突中央高度中段大于上段和下段，T12～L1的棘突顶距为54．91mm，至L2～3，增大为59．35mm，L4～5减小为47．13mm。L3的棘突高度最大，为21．56mm，上一棘突下缘大于相邻下一棘突上缘厚度。女性棘突较男性棘突短薄矮（P〈0．05～P〈0．01）。结论：本研究可模拟生理状态下腰椎棘突间区解剖，所测指标呈正态分布，能够反映国人腰椎棘突间区解剖，为腰椎棘突间内固定器的设计和临床的应用及计算机导航手术系统的应用提供解剖学基础。     

颈椎后路术后颈椎曲度不良与疗效的相关性

目的：探讨颈椎后路手术治疗颈椎退变性疾病后颈椎曲度不良与疗效的相关性。方法：采用颈椎后路减压术治疗颈椎退变性疾病患者85例,其中全椎板减压术26例、单开门椎管扩大成形术39例和单开门棘突重建扩大成形术20例,观察手术后颈椎后凸畸形对治疗效果的影响。结果：经6-72个月,平均18个月随访,颈椎后凸与否,各组之间神经功能改善率差异无统计学意义（P〉0.05）;单开门椎管扩大成形术与单开门棘突重建椎管扩大成形术,术后颈椎后凸发生率低于全椎板减压术（P〈0.05）;颈椎无后凸与轻度后凸（与A、B、C的对应关系）畸形之间的轴性症状发生率无差异,但与明显后凸组相比有差异性（P〈0.05）。结论：颈椎后路减压术是治疗颈椎退变性疾病常用的手术方法,具有椎管容积扩大明显等优点。但减少手术对后方肌肉韧带复合体损伤并对此复合体进行有效修复,可以减少颈后凸畸形和轴性症状发生,提高手术效果。     

Unilateral hyperplasia of lamina and spinous process of C6 vertebra: case report

We report a 20-year-old male patient who was admitted to our emergency clinic after a traffic accident and who suffered from neck pain. Radiographic examination of the cervical spine showed hypertrophy of the left lamina and hypertrophy and elongation of the left spinous process of the sixth cervical vertebra (C6). A computed tomography scan revealed the associated schisis of the spinous process at the same level. Magnetic resonance imaging scan demonstrated no abnormality of the neural elements. The patient underwent a surgical operation due to persistent neck pain and the local aesthetic abnormality.     

Lumbar shape characterization of the neural arch and vertebral body in spondylolysis: A comparative skeletal study

The lumbar vertebral shape is an important causative factor in spondylolysis (SP). However, a complete characterization of this shape, that would shed light on its pathophysiology enhance its earlier diagnosis, is still missing. The aim of this study was to evaluate the shape distinctiveness of the lumbar (L1-L5) vertebral body (VB) and neural arch (isthmus, lamina, vertebral canal, spinous, and transverse processes) in SP. Using a three-dimensional (3D) digitizer, the VB length, width, height, and sagittal wedging as well as the lengths of the isthmus, lamina spinous, and transverse processes of all lumbar vertebrae (L1-L5) were measured from 115 male skeletons with bilateral SP at L5 and compared with 120 normal ones. Compared with the normal group, the following results were indicated in SP [analysis of variance (ANOVA), P < 0.05]: the VB's are significantly longer at the superior surfaces of L1-L4 and inferior surfaces of L1-L3 (total mean difference = 7.61 mm and 3.94 mm, respectively), and wider at the superior surfaces of L1-L4 and inferior surfaces of L1-L5 (total mean difference = 10.06 mm and 12.90 mm, respectively); The L5 VB is significantly shorter posteriorly (mean difference = 3.05 mm) and more lordotic (+1° of dorsal wedging); L5 is manifested with longer lamina (mean difference = 1.85-2.18 mm), longer isthmus (mean difference = 3.24-4.69 mm), and longer and wider vertebral canal (mean differences = 3.64 mm and 1.13 mm, respectively); The L2-L5 spinous processes are significantly longer (total mean difference = 7.45 mm). Clinically, detecting the aforementioned unique lumbar vertebral morphometric features in individuals suffering from chronic low back pain may facilitate the early diagnosis of SP.     

Construction of a Statistical Cervical Vertebrae Geometric Model for Children 3–10 Years Old

Cervical spinal injuries of children in motor vehicle crashes have high morbidity and mortality rates. Cervical vertebrae change rapidly in both size and shape during growth. To accurately assess the risk of spinal injury for children of different ages, it is necessary to understand how the spatial geometric features of vertebrae change with the child’s age and neck size. In this study, an innovative semi-automated method was developed that can extract and align geometric points from computed tomography scans to accurately represent complex three-dimensional vertebral geometry. Based on these spatial geometric points, a statistical cervical vertebrae geometry model for children aged 3–10 YO was established based on principal component analysis and multivariate regression. According to this model, the vertebra spatial geometries for children of different ages and neck circumferences were represented, and its variation with age were accounted for. Statistical results show that age has a significant effect on anterior–posterior length (APL), transverse process width (TPW), vertebral body circumference (VBC) and height (VBH), whereas the significance of location and its interaction with age effects on these four parameters are different. The VBC and VBH increase more rapidly with age than the APL and TPW. In addition, the APL of C6 and C7 increase significantly faster than that of C3. As for the shape changes with child growth, the inclination angle of the upper surface of the lateral mass for C1 and the tilt angle of the articular process of the articular facet joint for C3–7 increase; and the shape of odontoid process of C2 becomes higher and steeper. This study can provide geometric basis for developing multiple pediatric cervical finite element models and anthropomorphic test devices to further quantify child neck injury risk with different ages and neck geometries.