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.     

颈椎拔伸旋转手法内在应力的实时监测

目的研究颈椎拔伸旋转手法内在应力的分布特点。方法应用有限元分析软件在颈椎CT片基础上逐步重建C3/4～C6/7颈椎模型并网格化。将颈椎拔伸旋转手法分解后的各项力学参数代入模型进行计算分析,即时显示手法作用时模型内在应力的变化。结果拔伸过程,模型应力集中的区域及大小呈由大减少再增大的趋势,应力主要在C3/4关节突关节;拇指向左推C4棘突过程中,C4棘突的左下部、根部、棘突左侧根部与椎弓根结合处先后出现应力集中,最大应力为9.627kPa;颈椎向右旋转40°的过程中,C3～6双侧关节突关节,C4～6的椎弓、棘突根部、二者结合处及椎体侧方等都先后出现应力集中,右侧C3/4关节突关节应力最大,为363.6kPa。颈椎快速返回中立位,模型应力集中的区域及大小均快速减少。结论颈椎拔伸旋转手法下的颈椎有其独特的应力变化规律。关节突关节在颈椎活动中承受主要应力。右旋40°时模型所受压力最大,但不会损伤正常颈椎骨性结构。     

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。     

Shape analysis of the cervical spinous process

Most textbooks describe the bifid spinous process as a shape associated with the typical cervical vertebra. Somewhere later they may acknowledge that cervical vertebrae are not always bifid, and that its appearance may be asymmetric. A high incidence of bifid cervical spinous processes may be a human characteristic, but because of known racial/geographic variation it may not be a very good one. Rarely can one find a satisfactory explanation of the functional or developmental basis for this shape variation. This article explores the distinctive shape of the cervical spinous process. Analysis is based upon the spinous processes of the third through seventh cervical vertebrae from fifty individuals. Shape differences were evaluated using the techniques of geometric morphometrics. Statistical comparisons were based upon 1000 permutations of a MANOVA based analysis. Significant shape differences were identified among the cervical vertebrae. However, post hoc analysis failed to identify significant differences between the C3 and C4 and between the C4 and C5 spinous process shapes. Primary shape differences were due to the depth of the bifid separation and the length of the process. Vertebrae with shorter spinous processes tended to display a more pronounced bifid condition. Combined observations from this and several other investigations suggest that a combination of variation in the spinalis cervicis muscle and behavioral patterns associated with cervical load may provide the best explanation for the shape variation in the cervical spinous process. Clin. Anat. 30:894–900, 2017. © 2017 Wiley Periodicals, Inc.     

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.     

Cribriform adenocarcinoma of the minor salivary gland arising in the tonsil with metastasis to a cervical lymph node: A case report with description of fine needle aspiration cytology

Cribriform adenocarcinoma of minor salivary gland (CAMSG) is a rare tumor of the head and neck. We report a case of a 70‐year‐old female who presented with a 4–5‐month history of a left neck mass. CT scan of the neck showed a left neck mass just inferior to the angle of the mandible and left tonsillar prominence. Fine‐needle aspiration (FNA) of the neck mass showed epithelial groups with focal cribriform architecture. The cells had round to oval nuclei and fine chromatin. The background contained scattered lymphocytes. A preliminary diagnosis of low grade adenocarcinoma with cribriform features metastatic to a lymph node was made. Subsequent biopsy of the tonsil mass showed a tumor with a combination of tubular, solid, and papillary architecture containing round to ovoid nuclei with very fine chromatin, consistent with cribriform adenocarcinoma of the minor salivary gland. Cribriform adenocarcinoma of minor salivary gland has a documented tendency to metastasize to cervical lymph nodes. Since this neoplasm can cytologically and histologically resemble other neoplasms of the head and neck, including polymorphous low‐grade adenocarcinoma (PLGA), papillary thyroid carcinoma (PTC), and occasionally adenoid cystic carcinoma, being aware of and familiar with the cytologic features of CAMSG on FNA smears is important for patient management. Diagn. Cytopathol. 2017;45:468–471. © 2017 Wiley Periodicals, Inc.     

胸廓出口综合征患者颈项部牵涉痛机制探讨—荧光素逆行双标法

目的：应用荧光素逆行双标法,研究胸廓出口综合征患者（thoracic orlet syndrome,TOS）颈项部牵涉痛的神经解剖学机制。方法：8只Wisatr大鼠,用荧光素逆行双标法,将荧光素快蓝（FB）注入颈椎关节突关节周围,核黄（NY）于近椎间孔处注入C5神经前支外膜下,观察颈部DRG中标记细胞。结果：在颈部的C5、C6DRG中发现荧光素双标细胞以及两种单标细胞,以中小细胞为主。结论：颈部的背根神经细胞周围突有分支投射到颈椎关节突关节及C5前支,提示TOS患者颈项部疼痛的发生机制可能与DRG中感觉神经元周围突分支有关。     

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.     

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。     

有限元分析颈椎棘突骨折内固定有效性

通过对颈椎棘突骨折(累及椎板)内固定治疗有限元模型的建立和分析,明确此种治疗方式对颈椎棘突骨折的有效性。先建立正常全颈椎(C0-T1)的有限元模型并与文献报告进行对比验证,模型验证后,在正常模型基础上建立颈椎棘突骨折(累及椎板)模型,并模拟直型接骨板行内固定治疗,测量并比较颈椎棘突骨折模型及手术内固定模型和原始正常模型在前屈、后伸、左右侧弯、左右旋转6种条件下活动度改变。以及颈椎各结构的应力变化。结果表明,在正常模型上结合临床病例建立的颈椎棘突骨折(累及椎板)外观逼真,生物力学相似度良好。骨折模型部分节段,主要为C7-T1的活动度(前屈+后伸9.20°,左右侧弯5.83°,左右旋转13.12°)较正常模型(前屈+后伸7.11°,左右侧弯4.92°,左右旋转 9.59°)增大,尤其是旋转活动度,模拟植入内固定后稳定性增加(前屈+后伸4.07°,左右侧弯2.21°,左右旋转2.91°),且内固定钢板应力分析提示,承受最大应力值在安全范围。颈椎棘突骨折(累及椎板)及内固定模型可以较好地模拟临床实际病例,通过有限元分析预示,此型骨折存在潜在不稳的可能性,探讨微型棘突钢板在骨折手术治疗中的应用,具有一定的临床参考价值。     

The effects of vagotomy on compensatory ovarian hypertrophy and follicular activation after unilateral ovariectomy

Following unilateral ovariectomy in the rat, the remaining ovary undergoes rapid compensatory changes including an increase in the number of antral follicles (follicular activation) and an increase in ovarian weight (compensatory ovarian hypertrophy). The ovary is innervated by the vagus nerve (Burden et al., 1983). In the present study, the effects of right and left cervical vagotomy and abdominal vagotomy on follicular activation and compensatory ovarian hypertrophy in the remaining right or left ovary were compared 15 days after unilateral ovariectomy. Neither right nor left cervical vagotomy affected compensatory ovarian hypertrophy of the right or left ovaries but abdominal vagotomy depressed compensatory ovarian hypertrophy in both the right and left ovaries. Left cervical vagotomy did not inhibit follicular activation, but right cervical vagotomy prevented follicular activation in the right but not left ovary. Also, abdominal vagotomy inhibited follicular activation in the right but not the left ovary. In animals with both ovaries which were subjected to the left or right cervical vagotomy or abdominal vagotomy follicular counts in both right and left ovaries were similar. Collectively, these data indicate that the vagus nerve participates in follicular activation after unilateral ovariectomy. The data also indicate that the right ovary is more dependent on vagal influences for follicular activation than the left ovary.     

Management of chronic pain of cervical disc herniation and radiculitis with fluoroscopic cervical interlaminar epidural injections

Study Design: A randomized, double-blind, active controlled trial.Objective: To evaluate the effectiveness of cervical interlaminar epidural injections of local anesthetic with or without steroids in the management of chronic neck pain and upper extremity pain in patients with disc herniation and radiculitis.Summary of Background Data: Epidural injections in managing chronic neck and upper extremity pain are commonly employed interventions. However, their long-term effectiveness, indications, and medical necessity, of their use and their role in various pathologies responsible for persistent neck and upper extremity pain continue to be debated, even though, neck and upper extremity pain secondary to disc herniation and radiculitis, is described as the common indication. There is also paucity of high quality literature.Methods: One-hundred twenty patients were randomly assigned to one of 2 groups: Group I patients received cervical interlaminar epidural injections of local anesthetic (lidocaine 0.5%, 5 mL); Group II patients received 0.5% lidocaine, 4 mL, mixed with 1 mL of nonparticulate betamethasone.Primary outcome measure was ≥ 50 improvement in pain and function. Outcome assessments included Numeric Rating Scale (NRS), Oswestry Disability Index (ODI), opioid intake, employment, and changes in weight.Results: Significant pain relief and functional status improvement (≥ 50%) was demonstrated in 72% of patients who received local anesthetic only and 68% who received local anesthetic and steroids. In the successful group of participants, significant improvement was illustrated in 77% in local anesthetic group and 82% in local anesthetic with steroid group.Conclusions: Cervical interlaminar epidural injections with or without steroids may provide significant improvement in pain and function for patients with cervical disc herniation and radiculitis.     

寰枢关节错位与胸锁乳突肌和斜方肌疼痛的解剖关系的初步研究

目的　观察寰枢椎与副神经及第2颈神经的解剖关系,以及观察胸锁乳突肌和斜方肌的神经支配特点,为寰枢关节错位致胸锁乳突肌和斜方肌疼痛提供解剖学依据。 方法　对3具共6侧成年人颈部尸体标本进行解剖,观察寰椎横突与副神经、寰枢外侧关节与第2颈神经前支、寰枢椎椎间孔外韧带的解剖结构,以及观察胸锁乳突肌和斜方肌的神经支配特点,测量副神经与寰椎横突尖的最短距离。 结果 (1)胸锁乳突肌和斜方肌均受副神经和颈丛（第2~4）神经支配,并且副神经与颈丛神经存在交通支联系。(2)副神经走行在寰椎横突前方,二者关系密切,副神经与寰椎横突尖的距离为4.84~7.60 mm(左侧)和3.22~6.80 mm（右侧）。(3)寰枢椎存在椎间孔外韧带,该韧带与第2神经相连,并附着在寰椎横突。(4)第2颈神经前支贴着寰枢外侧小关节向前走行。 结论 寰枢关节错位可能会刺激副神经及第2颈神经或其前支,从而引起胸锁乳突和斜方肌紧张、疼痛。     

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。     

The branching pattern of the aortic arch in the long-legged buzzard (Buteo rufinus Cretzschmar 1829)

The aim of this study was to investigate the vascular branching morphology of the aortic arch in the long-legged buzzard. For this purpose, two long-legged buzzards were evaluated in this study. The latex injection method was used to investigate the branching of the aortic arch. Two innominate brachiocephalic trunks branched continually from aortic arch caudoventral to the primary bronchi and ventral to the syrinx. The left subclavian artery gave rise to sternoclavicular, thoracic, axillary and intercostal arteries in this region. On the right side, it was observed that the right subclavian artery gave off thoracic, sternoclavicular and intercostal arteries, and the axillary artery was the branch of thoracic artery differently from the left one. Each carotid artery was continued to the middle of the neck and soon disappeared, becoming covered by the muscles of the anterior part of the neck, and entering the canal formed by the inferior spinous processes of the cervical vertebrae, within which it ran hidden, and in close contact with its fellow of the other lateral side, to near the head. This morphological study in the long-legged buzzard will elucidate the vascular organization for regional blood supply, and provide specific anatomical data.     

Ligamentous connections of the spinal processes

In the cervical region the fibres of the interspinous and nuchal ligaments pass in an anterocranial direction: they act against diminishing of the cervical lordosis. In the thoracic region, longitudinal bundles of fibres connect the tops of the spinous processes; they act against an augmentation of the thoracal kyphosis. Between thoracal kyphosis and lumbal lordosis there is no exact course of the fibres of the interspinous ligts. ("thorakolumbaler Ubergangsbereich"). In the lumbar spine the fibres of the interspinous ligts., being very strong, pass in a posterocranial direction. They have the function of limitation the range of flexion ventrally and of limiting backwards-shifting of the cranial vertebra in dorsal-flexion. In the lumbosacral segment additional fibres, arising from the top of the 5th lumbar spinous process, pass in a posterocaudal direction and interlace with the thoracolumbar fascia, whose fibres form--below the 4th lumbar vertebra--a scissor-latticed structure. The supraspinous ligt. lies superficially to the thoracolumbar fascia. Its fibres pass several spinous processes. It ends caudally at the 4th lumbar spinous process.     

Persistent cervical intersegmental artery and aortic arch coarctation

A 15-year-old girl presented with upper extremity hypertension and continuous precordial murmur. Arteriography revealed aortic coarctation proximal to the origin of the left subclavian artery. An anomalous artery originated from the aortic arch, between the left common carotid artery and the stenosis. It ascended cranially and filled an angiomatous vascular formation on the left side of the neck. The "angioma" drained into the left subclavian artery. The embryological explanation of the described anomaly is difficult, but probably related to hemodynamic alterations following the prestenotic increase in blood pressure. This may have impaired the obliteration of cervical intersegmental arteries, resulting in the persistence of one of the first three intersegmental arteries as the anomalous branch of the aortic arch. The angiomatous vascular formation in the neck could be the consequence of altered development of anastomoses between the muscular twigs of both vertebral and deep cervical artery. The vessel draining the vascular formation was probably the thyrocervical trunk. Since there were no overt collateral channels or signs of left ventricular hypertrophy by electrocardiography and echocardiography, it seems that the aberrant collateral flow was hemodynamically significant and reduced the afterload on the myocardium. Although the pattern of collateral flow in our case might be considered extremely rare, it is important in preoperative planning and interpretation of imaging studies.     

颈椎定点旋转手法“点”的数字化解剖

背景：虽然颈椎定点旋转复位手法效果显著,但其机制一直缺乏深入的研究。临床上对所要实施的推拿力和旋转节段无法做到精确控制,有时会造成手法的医源性损伤。 目的：从颈椎定点旋转手法旋转中心点的角度分析旋转手法的作用途径。 方法：在64排螺旋CT工作平台扫描标本,层距1 mm。在PHILIPS MEDICAL SYSTEMS图像处理功能模块中提取图片中轮廓线数据,进行上颈椎三维结构重建和图像显示。取枢椎棘突顶点(A点)、齿突垂直轴心(B点)以及两者之间连线的中点(C点)为旋转轴心(模拟中的旋转中心点),分别以各点为原点建立球坐标系。观察枢椎棘突顶点与下颌尖旋转前后的连线夹角,以及齿突垂直轴心与下颌尖旋转前后的连线夹角。 结果与结论：做定点手法旋转时其中心并非是施术者利手作用的枢椎棘突顶点,而是枢椎齿突垂直轴心;实际轴心旋转角>术者观察角。提示应建立颈椎定轴旋转的新概念,并掌握颈椎定轴旋转手法的原则,以指导临床正确应用脊柱旋转类手法。     

Transverse fractures of the spinous process of the 7th cervical vertebra in RDT patients: an Al related disease?

Transverse fractures of the spinous process of the 7th cervical vertebra were noted in 2 patients and of the 1st thoracic vertebra in 1 patient on maintenance hemodialysis. Two patients with aluminum (Al)- and/or iron-related bone disease complained of bone pain, relieved by deferoxamine therapy. In all three cases, the bone fractures had occurred suddenly while the patients were going about their daily work. These observations indicate that Al- or iron-related bone disease with secondary hyperparathyroidism can induce bone fracture by only slight stress in patients maintained on hemodialysis.