Surgical anatomy of the cervical sympathetic trunk

Lack of knowledge of the anatomy of the cervical sympathetic trunk (CST) may complicate surgical procedures on the cervical spine. This study aims to define linear and angular relations of the CST with respect to consistent structures around it, including the number and size of the cervical ganglia, the distances between the CST and the longus colli muscle and the anterior tubercles of the transverse processes of cervical vertebrae. Morphometric parameters of the 24 CSTs of 12 adults were measured on both sides. The CST had superior, middle, and inferior (or cervicothoracic) ganglia in 20.8% of specimens; superior and inferior (or cervicothoracic) ganglia in 45.8%; superior, middle, vertebral, inferior, or cervicothoracic ganglia in 12.5%, and superior, vertebral, inferior or cervicothoracic ganglia in 20.8% of specimens. The superior ganglion was observed in all specimens, the middle ganglion and vertebral ganglion were each observed in 33.3%. There was no difference between the number of superior and vertebral ganglia between the right and left sides. The average distance between the CST and the medial border of the ipsilateral longus colli muscle (LCM) was 17.2 mm at C3 and 12.4 mm at C7. As the CSTs converged caudally, the LCMs diverged. The average distance between the anterior tubercles of transverse processes of the cervical vertebrae and the lateral borders of the ipsilateral CST was 3.4 mm at C4, 3.2 mm at C5, and 3.9 mm at C6. The presence of a vertebral ganglion and variations, such as the localization of the CST within the carotid sheath, are important. The anatomical landmarks described should assist the spinal surgeon to avoid injury of the CST.     

Neuroanatomy and clinical analysis of the cervical sympathetic trunk and longus colli

Anterior cervical surgery is commonly used for cervical vertebral body lesions. However, the structure of blood vessels and nerve tissues along the route of anterior cervical surgery is complex. We aimed to measure the data of the longus colli, the sympathetic trunk and the cervical sympathetic trunk (CST) ganglia in Chinese cadaver specimens. A total of 32 adult cadavers were studied. We delineated the surgical anatomy of the CST. The superior and inferior/cervicothoracic ganglia of the sympathetic trunk consistently appeared. The middle ganglion was observed in 28.1% of the specimens and there were 2 cases of unilateral double middle cervical ganglia. The inferior ganglion was observed in 25.0% of the specimens and the cervicothoracic ganglion was observed in the remaining specimens. The distance between the CST gradually decreased from the top to the bottom, and the distance between the medial edges of the longus colli gradually broadened from the top down. The average angle between the bilateral CST and the midline of the vertebra was 11.2°±1.8° on the left side and 10.3°±1.4° on the right side. The average angle between the medial margins of longus colli of both sides was 11.1°±1.9°. The CST is at high risk when LC muscle is cut transversely or is dragged heavily, especially at the levels of C6 and C7. Awareness of the regional anatomy of the CST could help surgeons to identify and preserve it during anterior cervical surgeries.     

Cervico-thoracic ganglion: its clinical implications

Lesions of the cervicothoracic ganglion (CTG) result in interruption of sympathetic fibers to the head, neck, upper limb, and thoracic viscera. The accurate understanding of the anatomy of the CTG is relevant to sympathectomy procedures that may be prescribed in cases where conventional intervention has failed. This study documents the incidence and distribution of the CTG to avoid potential complications such as Horner's syndrome and cardiac arrhythmias. This study utilized 48 cadavers, in which a total of 89 sympathetic chains were dissected. The inferior cervical ganglion (ICG) and the first thoracic ganglion was fused in 75 cases (84.3%) to form the CTG. It was present bilaterally in 48 of these specimens (65.3%). Three different shapes of CTG were differentiated, viz. spindle, dumbbell, and an inverted "L" shape. The dumbbell and inverted "L" shapes demonstrated a definite "waist" (i.e., a macroscopically visible union of the ICG and T1 components of the CTG). Rami from the CTG was distributed to the brachial plexus, the subclavian and vertebral arteries, the brachiocephalic trunk, and the cardiac plexus. This study demonstrates a high incidence of a double cardiac sympathetic nerve arising from CTG. It is therefore imperative that in the technique of sympathectomy, for intractable anginal pain, the surgeon excises both these rami but does not destroy the ganglion itself. The ever-improving technology in endoscopic surgery has made investigations into the nuances of the anatomy of the sympathetic chain essential.     

Anatomy of thoracic splanchnic nerves for surgical resection

Thoracic splanchnic nerves conduct pain sensation from the abdominal organs around the celiac ganglion. Splanchnicectomy is the procedure used mainly for the control of intractable visceral pain. Forty-six human posterior thoracic walls were dissected. The formation pattern, course, and incidence of communication of the thoracic splanchnic nerves were investigated. The greater splanchnic nerves (GSNs) were formed by nerve branches from the T4-T11 thoracic sympathetic ganglia and the most common type was formed by T5-T9 (21.7%). The uppermost branches originated from T4-T9 while the lowermost branches emanated from the T7-T11. Two to seven ganglia contributed to the GSNs. In 54.3% of the specimens, at least one ganglion in the GSN-tributary ganglionic array did not branch to the GSN. The lesser splanchnic nerves (LSNs) were formed by the nerve branches of the T8-T12 thoracic sympathetic ganglia and the most common type was formed by T10 and T11 (32.6%). One to five ganglia were involved in the LSNs. The least splanchnic nerves (lSNs) were composed of branches from the T10-L1 thoracic sympathetic ganglia and the most common type was composed of nerve branches from T11 and T12 or from T12 only (each 30.4%). One to three ganglia were involved in the lSNs. In 54.3% of the specimens, interconnection between the GSNs and the LSNs existed, bringing the possible bypass around the transection of the GSNs. The splanchnic nerves that appear in textbooks occurred in a minority of our specimens. We provided expanded anatomical data for splanchnicectomy in this report.     

Contribution of the cervical sympathetic ganglia to the innervation of the pharyngeal arch arteries and the heart in the chick embryo

In the chick heart, sympathetic innervation is derived from the sympathetic neural crest (trunk neural crest arising from somite level 10–20). Since the trunk neural crest gives rise to sympathetic ganglia of their corresponding level, it suggests that the sympathetic neural crest develops into cervical ganglia 4–14. We therefore tested the hypothesis that, in addition to the first thoracic ganglia, the cervical ganglia might contribute to cardiac innervation as well. Putative sympathetic nerve connections between the cervical ganglia and the heart were demonstrated using the differentiation markers tyrosine hydroxylase and HNK‐1. In addition, heterospecific transplantation (quail to chick) of the cardiac and trunk neural crest was used to study the relation between the sympathetic neural crest and the cervical ganglia. Quail cells were visualized using the quail nuclear antibody QCPN. The results by immunohistochemical study show that the superior and the middle cervical ganglia and possibly the carotid paraganglia contribute to the carotid nerve. This nerve subsequently joins the nodose ganglion of the vagal nerve via which it contributes to nerve fibers in cardiac vagal branches entering the arterial and venous pole of the heart. In addition, the carotid nerve contributes to nerve fibers connected to putative baro‐ and chemoreceptors in and near the wall of pharyngeal arch arteries suggesting a role of the superior and middle cervical ganglia and the paraganglia of the carotid plexus in sensory afferent innervation. The lower cervical ganglia 13 and 14 contribute predominantly to nerve branches entering the venous pole via the anterior cardinal veins. We did not observe a thoracic contribution. Heterospecific transplantation shows that the cervical ganglia 4–14 as well as the carotid paraganglia are derived from the sympathetic neural crest. The cardiac neural crest does not contribute to the neurons of the cervical ganglia. We conclude that the cervical ganglia contribute to cardiac innervation which explains the contribution of the sympathetic neural crest to the innervation of the chick heart. Anat Rec 255:407–419, 1999. © 1999 Wiley‐Liss, Inc.     

Correspondence: Communication between the superior cervical sympathetic ganglion and the inferior laryngeal nerve

Complex arborisations occurs between the inferior ganglion of the vagus nerve and the superior cervical sympathetic ganglion (Braeucker, 1923; Fick, 1926; Siwe, 1931; Hoffman, 1957). The superior cervical sympathetic ganglion sends branches to the internal and the external carotid arteries, the inferior vagal ganglion, the superior laryngeal nerve and the cervical nerves, and provides superior cardiac and thyroid branches as well as the trunk that descends directly to the middle and inferior cervical sympathetic ganglia. There are communications between the vagus nerve (laryngeal branches) and the superior cervical sympathetic ganglion (SCSG). Cannizzaro et al. (1991) and Zerilli et al. (1994) reported abnormalities of sympathetic function among the effects of injury to the superior laryngeal nerve during thyroid surgery. The interconnections between these various nerves are therefore of clinical importance. We document here a rare example of complex communication between the vagus nerve and the SCSG in dissections of 113 adult (78 male, 35 female) Japanese cadavers. Both sides were examined in 88 cases, the right only in 18 and the left only in 7 (i.e. 201 sides in total).     

Sympathetic neurons in lower cervical ganglia send axons through the superior cervical ganglion

In addition to the preganglionic axons which innervate the superior cervical ganglia, the cervical sympathetic trunks of the rat have been shown to contain axons of ganglionic neurons. Following the application of horseradish peroxidase to the cut cervical sympathetic trunk just caudal to the superior cervical ganglion, a population of approximately 300 labeled neurons was found in the inferior and middle cervical ganglia. The labeled neurons were localized primarily in the more rostral regions of these ganglia. The axons of most of these neurons entered the superior cervical ganglion, passed through it, and left via the external carotid nerve.The relevance of these observations to physiological studies on the cervical sympathetic nervous system is discussed     

狗肾上腺交感节后神经元的定位研究

用HRP逆行标记法研究狗肾上腺交感节后神经元的定位.标记细胞见于注射侧L_8-L_4节段的交感干神经节.在注射侧腹腔神经节、肠系膜前神经节和主动脉肾神经节内均见有大量标记细胞,表明支配肾上腺的交感节后神经元分布广泛,动物种间存在差异.     

Developmental Morphology and Topography of the Components of the Cervical Sympathetic Trunk in Sheep (Ovis aries) During the Fetal Period

The objective of this study was to clarify the typical architecture and morphological variations of cervical sympathetic trunk (CST) in sheep during fetal period. Components of CST were examined on both sides of 40 male and female sheep fetuses aged from 60 to 140 days under a stereomicroscope. Skeletotopy and frequency of presence of cranial cervical ganglion (CCG), syntopy of cervical ganglia, and composition and topography of vagosympathetic trunk were consistent among specimens whereas the shape of cervical ganglia, the skeletotopy and number of three middle cervical ganglia (MG), and the frequency of communicating branches of CCG to the first cervical spinal nerve exhibited differences during fetal period. A reduction in the number of MG and the caudal movement of main MG were noted by increasing fetal age. Based on these detailed findings, comparative and developmental anatomy and evolutionary changes are discussed and compared with previous studies. The number of MG, skeletotopy of CCG and main MG, the number and range of communicating branches of CCG to spinal nerves, and the association of vagus and sympathetic nerves in fetal sheep were fundamentally different from those of mostly reported species. These results suggest that data obtained from CST of fetal sheep are significantly different from those obtained from humans, and it is problematic to apply them to humans because of the more cranial position of CCG, very narrow contribution of CCG to spinal nerve, absence of the vertebral ganglion, existence of multiple MG, and no communicating branches from MG to spinal nerves. Anat Rec, 300:2250–2262, 2017. © 2017 Wiley Periodicals, Inc.     

Sympathetic nerve pathways to the human heart,and their variations

Stimulated by the needs of surgery, common variations in the sympathetic pathways to the heart have acquired a practical significance. The cervical and upper thoracic sympathetic trunk was dissected on 24 sides in human fetuses at term, and the cardiac rami together with their communications studied and illustrated. To enable us to classify the cervical rami according to their sites of origin, the cervical sympathetic trunk was subdivided midway between ganglia into portions called ganglionic divisions; these divisions keeping the names applied to the ganglia in the Nomina Anatomica. Intermediate ganglia were found on the visceral outflow of the sympathetic trunk and are referred to as “distal intermediate ganglia” to distinguish them from the intermediate ganglia that have been described proximal to the sympathetic trunk. Thoracic cardiac rami were almost invariably present, the third and fourth thoracic ganglia most frequently providing substantial contributions. Some thoracic cardiac rami were traced as far as the left anterior descending coronary plexus. The question of bilateral symmetry was also examined. Whilst a variety of features are commonly present on both sides, the first dissection in a cervicothoracic sympathectomy is no reliable guide to the detailed anatomy of the second side. The sympathetic pathways to the heart are extremely variable in their topography, and the diversity of arrangements encountered accounts for the morphological contradictions in the literature. So numerous are the possible variations that the outcome of a sympathectomy is unpredictable. Where denervation is incomplete, collateral sprouting and regeneration of nerves could even lead to hyperstimulation via the sympathetic pathways.     

肾脏的交感神经支配

采用大体解剖学方法和肾内注射HRP逆行标记神经元的方法,研究了猫肾脏的交感神经支配。发现了下述的待点。1.猫左、右侧腹腔神经节相互融合,呈半环状包绕在肠系膜上(前)动脉的起始处,于其融合部,各发出左、右肾支。肠系膜上神经节与右侧腹腔神经节融合。2.肾交感神经节后神经元,分别位于腹腔神轻节,同侧主动脉肾神经节和T_(12)～L~4节段的交感干神经节内,並具有局部定位分布的关系。3.肾交感神经节后纤维主要来自腹腔神经节(82.08％),其次是主动脉肾神经节(12.76％),交感干神经节最少(5.16％)。4.肾交感神经节后神经元,多呈圆形或椭圆形,交感干神经节中有少量呈梭形。5.支配肾周腹膜的交感神经节后神经元与肾交感神经节后神经元存在部位、数量和在各种神经节内分布形式均不相同。     

山羊迷走神经中的交感节后纤维成分

在山羊颈前部或后部手术分离迷走神经与颈交感干,将辣根过氧化物酶(HRP)注入颈迷走神经干内,在所有实验例,均在颈前节看到标记细胞。但是,将HRP注入颈交惑干,在颈前节无标记细胞.这个结果表明,颈前节的交感节后神经元发出纤维加入迷走神经,下行到达所支配的颈、胸和腹腔内脏器官。     

Histological verification of the prehypogastric and ovarian ganglia confirms a bilaterally symmetrical organization of the ganglia comprising the aortic plexus in female human cadavers

The aortic plexus is a network of sympathetic nerves positioned along the infrarenal abdominal aorta. Recently, we characterized the aortic plexus and its ganglia (inferior mesenteric, left/right spermatic, and prehypogastric ganglion) in males; however, the literature minimally describes its anatomy in females. In the present study, we conducted the first histological examination of the left and right ovarian ganglia, while also investigating whether females, like males, exhibit a prehypogastric ganglion. The ganglia were dissected from embalmed (n = 32) and fresh (n = 1) human cadavers, and H&E staining was used to confirm the presence of a left ovarian ganglion in 31/31 specimens, a right ovarian ganglion in 29/29 specimens and a prehypogastric ganglion in 25/28 specimens. Comparable to the topographic arrangement in males, there is a bilateral organization of the ganglia comprising the aortic plexus in females. More specifically, the left and right ovarian ganglia were positioned in close relation to their respective ovarian artery, whereas the prehypogastric ganglion was positioned within the right cord of the aortic plexus, contralateral to the inferior mesenteric ganglion. Using immunohistochemistry, it was shown that all ganglia from the fresh cadaver stained positive for tyrosine hydroxylase, thereby confirming their sympathetic nature. Having provided the first topographical and histological characterization of the ovarian and prehypogastric ganglia in females, future studies should seek to determine their specific function.     

Origin of sympathetic efferent axons in the renal nerves of the cat

The origin of efferent axons in the renal nerves of the cat was examined using retrograde transport of horseradish peroxidase (HRP). Nerves on the surface of the left renal blood vessels were dissected 5-7 horseradish mm proximal to the medial margin of the kidney, transected and the central cut ends exposed to HRP. Labeled neurons were typically identified in three locations: (1) centrally along the renal nerve, (2) in the superior mesenteric ganglion, and (3) in the ipsilateral sympathetic chain ganglia (T12-L3). HRP was not detected in preganglionic neurons in the thoracolumbar spinal cord. Labeled cells ranged in size from 15 to 50 micrometers, with those in the renal nerve at the smaller end of the spectrum and those in the superior mesenteric ganglion at the larger end. In the superior mesenteric ganglion labeled cells were typically localized to a small region in the caudal pole of the ganglion around the origin of the renal nerve. The results show that the sympathetic efferent innervation of the kidney is derived from both paravertebral and prevertebral ganglia. In the latter (superior mesenteric ganglion), renal efferent neurons exhibited a topographic distribution.     

Anatomical variations of the upper thoracic sympathetic chain

The aim is to clearly delineate the upper thoracic sympathetic chains and neural connections between the chains and ventral rami of the thoracic nerves, and to provide an anatomical foundation for successful upper thoracic sympathicotomy for treating upper essential hyperhidrosis. The upper thoracic sympathetic chains, upper five intercostal nerves, and neural connections between them in 50 halves of 25 adult cadavers have been dissected, measured, and mapped. The stellate ganglion had an incidence of 80%. The second to the fourth thoracic sympathetic ganglia were commonly located in the corresponding intercostal spaces with the presence of 92%, 68%, and 50%, respectively. The incidence of the first and second intercostal rami was 40% and 6%, and that of the ascending or descending rami from the second, third and fourth ganglia was 54%, 24%, and 14%, respectively. Additional rami communicantes joined the ventral ramus of the 1st thoracic nerve proximal to the point where the latter gave a branch to the brachial plexus. The farthest horizontal distance from the sympathetic chain to the junction between the additional rami communicantes and the second to the fourth intercostal nerves was 29.1 mm. Only 16% of cadavers had similar anatomy bilaterally. Anatomical variations of the upper thoracic sympathetic trunk in relation to intercostal nerves, which may be one of the causes resulting in surgical failures and recurrences, were striking. Attention should be given to such anatomical variations when planning thoracic sympathicotomy. Clin. Anat. 22:595–600, 2009. © 2009 Wiley‐Liss, Inc.     

颈前外侧入路的应用解剖学研究

目的　为颈前外侧入路手术提供应用解剖学基础。 方法　对10具标本模拟右侧颈前外侧入路进行解剖观测。 结果　颈总动脉的分叉在C4水平为70%。面静脉70%在C3/4椎间盘水平注入颈内静脉。颈交感干位于椎前筋膜下方,行于颈动脉鞘的正后方,并在头长肌和颈长肌表面纵向延伸。C6水平颈交感干和颈长肌内侧缘之间的距离（14.5±4.8）mm, C6水平颈交感干的直径为（2.6±1.2）mm。上神经节位于C2水平,长度和宽度分别是（11.9±2.5） mm和（7.4±4.2）mm。中神经节位于C5水平4例,C6水平6例。长度和宽度分别是（8.9±5.9）mm和（5.1±3.2）mm,椎动脉无一例外都穿过C6横突孔上行。C5的钩突的高度和宽度是最小的,但是从钩突的内侧缘到横突的前结节却拥有最长的距离（P<0.05）。 结论　采用该入路对于颈椎前外侧的病理性损害具有直达病变部位、损伤小、减压彻底,最大程度上保留病变节段的运动性和脊柱的稳定性等优点。     

颈胸段脊柱手术前方入路的应用解剖

目的:通过对颈胸段脊柱周围重要解剖结构的分布、走行及毗邻关系的研究,为颈胸段脊柱选择合理的手术入路提供解剖学基础。方法:对30具成人尸体模拟经胸骨柄和部分锁骨切除的颈胸段脊柱前方入路进行解剖,采用连续层次解剖法,重点观察前方手术入路途径中必须牵拉和需要保护的几个重要组织,并测量相关数据。结果:左头臂静脉的长度为(67.3±9.7)mm,左静脉角与前正中线的水平距离为(45.0±8.3)mm,头臂静脉与头臂干交点距胸骨上切迹的垂直距离为(52.7±20.1)mm;胸膜顶最高点距锁骨内1/3上缘的垂直距离,左侧(8.1±2.0)mm右侧(13.7±2.8)mm胸导管顶点80%位于第7颈椎(C_7)水平,胸导管顶点距前正中线的距离为(33.78±2.16)mm;左喉返神经进入气管食管沟的位置93.4%位于第3、4胸椎~第4、5胸椎(T_(3/4)~T_(4/5))之间,右喉返神经进入气管食管沟的位置30%位于C_(6/7)水平,60%位于C_7水平,右喉返神经与颈总动脉内侧缘交叉点90%位于T_1水平;主动脉弓顶点90%位于T_(2/3)~T_(3/4)椎体水平。结论:颈胸段脊柱前路手术采取左侧入路,术野暴露更充分,操作更方便,同时术中通过对左头臂静脉的牵拉和结扎胸导管可减少医源性并发症的发生。     

Systematic Morphology and Evolutionary Anatomy of the Autonomic Cardiac Nervous System in the Lesser Apes,Gibbons (Hylobatidae)

We examined the morphology of the autonomic cardiac nervous system (ACNS) on 20 sides of 10 gibbons (Hylobatidae) of three genera, and we have inferred the evolution of the anatomy of the primate ACNS. We report the following. (1) Several trivial intraspecific and interspecific variations are present in gibbons, but the general arrangement of the ACNS in gibbons is consistent. (2) Although the parasympathetic vagal cardiac nervous system is extremely consistent, the sympathetic cardiac nervous system, such as the composition of the sympathetic ganglia and the range of origin of the sympathetic cardiac nerves, exhibit topographical differences among primates. (3) The vertebral ganglion, seldom observed in the Old World monkeys (Cercopithecidae), was consistently present in gibbons as well as in humans. (4) There are fewer thoracic ganglia contributing to the cervicothoracic ganglion in humans than in gibbons and in gibbons than in Old World monkeys. (5) The superior cardiac nerve originating from the superior cervical ganglion, rarely observed in Old World monkeys but commonly observed in humans, was present in 13 of 20 sides (65%), mostly on the left. Accordingly, the ACNS morphology exhibits evolutionary changes within the primate lineage. These evolutionary differences between Old World monkeys, gibbons, and humans are most parsimoniously interpreted as resulting from regular changes in the lineages leading from their common ancestor to the extant species that we dissected. They include the reduction in the number of thoracic ganglia contributing to the cervicothoracic ganglion and the expansion of the range of the cardiac nervous origin. Anat Rec, 291:939–959, 2008. © 2008 Wiley‐Liss, Inc.