Vascular configurations of anastomotic basket of conus medullaris in human spinal cord

The arterial basket of the conus medullaris is one of several anastomoses between the anterior and posterior spinal arteries. The anatomy of this structure has attracted little attention. This work sought to investigate its configuration in human spinal cords. Spinal cords from male and female cadavers (n = 32) were injected with colored latex through the intercostal, lumbar, medial sacral and the posterior trunks of the hypogastric arteries. After injection, specimens preserving the dural sac were obtained and fixed in formaldehyde solution. Finally, the spinal arteries were microdissected. In 18.75% of the specimens, the anterior spinal artery divided symmetrically and formed anastomoses with the posterior spinal arteries. In 81.25%, the branching pattern observed was asymmetrical. In 21.87% there were differences in the diameter of the anastomotic arteries, and 40.63% originated at different levels along the craniocaudal axis. Interestingly, 12.5% of the specimens presented an intraparenchymatous anastomosis that has not been described previously. True unilateral anastomosis was only observed in 6.25% of the spinal cords. The most frequent configuration of the anastomotic basket of the conus medullaris is a bilateral asymmetric anastomosis. The asymmetry of the branches could be caused by differences in their diameters or in their origins along the craniocaudal axis. Symmetrical patterns are less frequent, and unilateral anastomoses are rare. In reality, some cases of apparently unilateral anastomosis present an intramedullary course of the anastomotic artery. Clin. Anat. 31:441–448, 2018. © 2017 Wiley Periodicals, Inc.     

颈神经根槽和颈椎间孔的应用解剖

目的：为颈椎病的病因、诊断和治疗提供补充的定量数据。方法：在干燥的颈椎椎骨标本和福尔马林固定的颈椎标本上，测量颈神经根槽和颈椎椎间孔。结果：内侧区的平均长度，内侧区前缘中点到椎体中线的距离从C3～C7逐渐增加。C3内侧区的宽度较大，C7上、下关节突及峡部高度之和的后中点到颈神经根槽后壁的前后距离最小。结论：研究结果为影像诊断和外科手术提供了相关的应用解剖数据。     

下颈椎血供的解剖研究及其临床意义

目的为颈椎前路减压手术中减少出血量,改善显露和减少手术并发症的发生提供解剖学基础。方法在15具成人尸体标本上,解剖观测C3～7椎体前后部血供的起源、走行、分支及吻合。结果椎体前部血供来自颈升动脉脊支、甲状腺下动脉和颈深动脉脊支,C4～7椎前动脉在椎体上的分支相互吻合,在颈长肌的内侧缘处常吻合成一纵行动脉链;椎体后部血供来自椎间动脉发出的椎后动脉,其分支在颈椎体后部吻合形成节段性弧形动脉吻合链。结论阻断术椎的椎前动脉及其与相邻椎前动脉的纵行动脉吻合,并在颈椎后部减压时注意对硬膜囊外侧缘及椎体中部处的椎后动脉及其分支的处理,可减少颈椎前路减压手术的术野出血,改善手术显露。     

The effect of anterior abdominal wall scars on the vascular anatomy of the abdominal wall: A cadaveric and clinical study with clinical implications

The anterior abdominal wall integument is frequently used in a range of reconstructive flaps. These tissues are supplied by the deep and superficial inferior epigastric arteries (DIEA and SIEAs) and the deep and superficial superior epigastric arteries (DSEA and SSEAs). Previous abdominal wall surgery alters this vascular anatomy and may influence flap design. One hundred and sixty‐eight patients underwent abdominal wall computed tomographic angiography (CTA) for preoperative imaging. Fifty‐eight of these patients had undergone previous abdominal surgery, and were assessed for scar pattern and relationship to the course and distribution of all major axial vessels and perforators. Two cadaveric abdominal wall specimens with midline abdominal scars underwent contrast injection of the DIEAs and DSEAs, with subsequent CTA. The course and distribution of all cutaneous vessels were assessed. In all clinical and cadaveric cases, the vasculature of the abdominal wall had been altered by previous surgery. In the clinical cases, vascular architecture was universally altered in the region of the scar, often modifying the filling patterns of the abdominal wall and occasionally precluding the use of an abdominal wall flap. In both cadaveric specimens, regions of non‐filling were evident upon contrast injection, highlighting the angiosomes not supplied by the DIEA or DSEA. Previous abdominal wall surgery necessarily alters the vascular architecture of the abdominal wall, and may alter the source vessels supplying cutaneous tissues. CTA was useful in identifying and delineating these changes, and may be used as a preoperative tool in this role. Clin. Anat. 22:815–822, 2009. © 2009 Wiley‐Liss, Inc.     

Danger of damaging the medial branches of the posterior rami of spinal nerves during a dorsomedian approach to the spine

Postoperative atrophy of the deep back muscles may be caused by denervation during a dorsomedian approach to the thoracolumbar spine; ensuing instability of the spine with poor clinical results, perhaps due to such muscle loss, has been observed in 11.7% of cases (Sihvonen et al., 1993, Spine 18:575--581). More specifically, this complication may be caused by damaging the medial branches of the posterior rami of the spinal nerves during lateral retraction of the muscles. To investigate the anatomic topography of the medial branches of the posterior rami of the spinal nerves, 18 carbol-formol-fixed specimens were dissected using an operation microscope; also, 3 fresh cadavers were cut in horizontal and vertical planes with a rotary cryotome to confirm the anatomic topography observed in the fixed specimens. In the thoracolumbar spine the medial branch of the posterior ramus of the spinal nerve is subject to ligamentous fixation by the strong fibers of the mammillo-accessory ligament, which extends between the mammillary process and accessory process infero lateral to the superior articular process. When the dorsomedian approach to the thoracolumbar spine is enlarged laterally to the articular processes by retracting the paraspinous muscles, the medial branches of the posterior rami of the spinal nerves are endangered. This may cause postoperative pain as well as dynamic instability beyond the corresponding segments. The results of our anatomic study suggest that the posterior surgical midline approach to the thoracolumbar spine should not be enlarged laterally to the articular processes to prevent injury to the medial branches of the posterior rami of the spinal nerves.     

小型猪皮瓣模型的影像解剖学研究

目的:研究小型猪躯干主要皮动脉血液供应,为皮瓣的相关研究提供动物模型和充分的解剖学依据。方法:(1)小型猪5头放血处死,动脉灌注明胶-氧化铅混悬液,运用CT扫描三维重建全身动脉系统。解剖观测躯干主要皮动脉的起源、行程、营养范围以及相互之间的吻合情况,并取下皮肤筋膜组织拍摄X线片。(2)活体小型猪1头静脉注射泛影葡胺,CT扫描三维重建全身动脉系统,与明胶-氧化铅灌注的三维重建行对照观察。结果:在动脉显影X线图像上,可见双侧的腹壁上动脉、肋间动脉穿支、旋髂深动脉构成腹前、侧壁的主要营养链,两两之间有丰富的吻合支,而腹壁下动脉、腹壁浅动脉和胸背动脉均未见粗大的皮肤穿支。全身动脉三维重建图像上,可见躯干主要皮动脉的来源、走行,管径相对大小,并可动态观察血管树的三维结构和相互关系。结论:小型猪躯干体被血运丰富,腹壁上动脉、肋间动脉穿支、旋髂深动脉皮支两两之间有丰富的吻合支,构成躯干体被组织的主要营养链,并可以此设计不同类型的皮瓣。     

颈椎后路手术相关结构三维可视化研究

目的寻求建立颈椎后路手术相关结构数字模型及三维可视化方法。方法取健康志愿者头顶至第3胸椎下缘连续CT/MRI断面图像,Mimics软件对骨骼,肌肉,神经等组织用半自动方法进行分割和重建,MedCAD(医学计算机辅助设计)模块对细小解剖结构重建,三维化显示颈椎后路手术相关解剖结构。结果建立颈椎后路手术相关结构的三维可视化模型,显示骨性结构、颈背部由浅入深4层17组肌肉、4组韧带、C1～T2脊神经后支和颈部浅层肌等解剖结构的位置关系。结论在颈背部三维可视化模型基础上,参照解剖学层次逐层显示该手术相关重要结构,为该手术解剖教学、手术培训提供医疗教学平台。     

Clinical importance of ligamentous and osseous structures in the cervical uncovertebral foraminal region

The vertebral artery, cervical spinal nerves, spinal nerve roots, and the bony and ligamentous tissue related to the cervical vertebrae are structures whose anatomy determines the path of a surgical approach. Defining the anatomy and, in particular, determining the precise location of vulnerable structures at the intervertebral foramen and the uncovertebral foraminal region (UVFR), a region defined by the uncinate process anteriorly, the facet joint posteriorly and the foramen transversarium laterally, has critical significance when selecting the safest surgical approach. We studied the anatomy of the vertebral artery, cervical spinal nerves, and spinal nerve roots within the UVFR in six cadaver specimens. We also obtained measurements of bony structures in 35 dry cervical vertebral columns, from C3-C7. The uncinate process (UP) projects superiorly from the posterolateral aspect of each cervical vertebral body, except for the first and second vertebrae. Because the posterior part of the UP lies adjacent to the vertebral artery, spinal nerve, and spinal nerve roots, its resection creates sufficient space to decompress these structures directly. The posterolateral surface of the UP is covered by ligamentous tissue that originates from the posterior longitudinal ligament and protects the neural and vascular structures during their decompression in the UVFR.     

上侧胸部穿支的应用解剖学研究

目的　对上侧胸部皮肤的血供分布规律进行解剖学研究,为上侧胸部皮瓣的设计提供解剖学依据。 方法　新鲜成人标本10具,灌注红色乳胶氧化铅混合物后行螺旋CT进行扫描,后数据输入Mimics 13软件进行三维重建;然后进行解剖,观察并记录第9肋以上腋中线周围管径大于0.5 mm的穿支的管径、穿出点、走形于筋膜的长度及与周围血管的吻合关系;将其中2具标本躯干的被覆组织剥离下来,行X线摄影。 结果　第3、第4肋间后动脉在侧胸壁的外侧支支常常缺失或管径细小。该区域的皮肤血供分布来源于旋肩胛动脉、胸外侧动脉及胸背动脉近端的穿支。10具标本共中解剖到了109支位于第5至第8肋间隙的肋间后动脉肌皮穿支;90%侧标本上有一支优势穿支的存在,外径为（0.9±0.3）mm。在25%的标本中,可以发现优势穿支与肩胛下动脉前锯肌支的分支有吻合。 结论　 ①上侧胸部可以切取以胸背动脉外侧支为蒂大型跨区皮瓣;②第5至第8肋间隙存在恒定的肋间后动脉外侧穿支,可以切取以肋间后动脉外侧穿支皮瓣来修复四肢及躯干部皮肤缺损。     

增加前路cage融合对颈椎曲度、稳定性及轴性症状的影响

背景：对于严重的颈椎间盘突出、后纵韧带钙化、黄韧带增生,实施前后联合入路不仅可以达到彻底减压的目的,同时植入cage及前路钢板矫形固定可部分恢复椎体间隙及颈椎生理曲度。 目的：比较颈椎病颈后路单开门椎管扩大成形及增加前路cage融合内固定对治疗后患者颈椎曲度、稳定性及轴性症状发生的影响。 方法：回顾性分析颈椎病外科治疗50例患者的临床资料。其中行一期前后联合入路脊髓减压(前路cage+钢板融合固定)22例(前后路联合治疗组);单纯行颈后路单开门椎管扩大成形(后路开窗铆钉固定)28例(单纯后路治疗组)。治疗后随访6-24个月,分别对两组治疗后神经功能恢复情况、轴性症状的发生率及颈椎曲度指数、病变节段椎间滑移度进行统计分析。 结果与结论：两组患者的神经功能恢复均获得较好的日本骨科学会(JOA)改善率,前后路联合治疗组患者轴性症状的发生率相对低,颈椎曲度指数较单纯后路治疗组患者有较为明显的改善,而单纯后路治疗组椎间滑移度相对较大。结果表明一期前后联合入路使用cage、前路钢板、后路铆钉行脊髓减压可以有效维持颈椎的生理曲度从而维持矢状面的平衡,减少患者轴性症状的发生率,对维持治疗后颈椎长期的稳定性起到重要作用。中国组织工程研究杂志出版内容重点：人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程全文链接：     

Scalenus muscles in macaque monkeys

The attachment and innervation of the scalenus muscles in both sides of two Japanese monkeys and a rhesus monkey were observed to discuss their morphological significance while comparing their findings in humans. The scalenus ventralis muscle in macaques had almost the same attachments as the scalenus anterior muscle in humans and was innervated by the cervical nerve branches, which were lower in spinal segment than in humans and had a close relationship with the branches to the intertransversus ventralis muscles. Furthermore, the scalenus ventralis muscle was penetrated by the phrenic nerve in all cases observed. The posterior part of the scalenus muscle in macaques (the scalenus dorsalis muscle) was divided into short (the scalenus dorsalis brevis) and long (the scalenus dorsalis longus) parts according to their attachments. The former was attached to the transverse processes of the lowest two cervical vertebrae and the first rib, whereas the latter was attached to the 3rd-5th ribs. It is notable that the scalenus dorsalis muscles in macaques were innervated by branches from the long thoracic nerve in addition to direct branches from the cervical nerve roots. In addition, the scalenus dorsalis longus was supplied by twigs from the lateral cutaneous branches of the 2nd and 3rd intercostal nerves. This indicates that the scalenus dorsalis muscles contain a muscular component derived from the upper limb girdle musculature, unlike the human scalenus muscles, which have been considered to belong to the cervical trunk muscles.     

Vascular system of the human spinal cord in the prenatal period: a dye injection and corrosion casting study.

The vascularization of the spinal cord was investigated in 50 human fetuses aged from 10 to 28 gestational weeks using dye injection methods and corrosion casting accompanied by scanning electron microscopy. In the investigated period of fetal development, the general vascular architecture of the spinal cord, corresponding to that described postnatally, seemed to be already established. The observed changes included: (1) remodeling of the supplying (extrinsic) arterial branches, (2) transformation of the posterior anastomotic chain into two distinct posterior spinal arteries, and (3) development of the capillary networks in the gray and white matter. The remodeling of the radicular arteries supplying the spinal cord was accompanied by a decrease in their number and transition from regular to irregular distribution (appearance of intersegmental differences in their frequency). The anterior spinal artery and regular array of the central arteries were already present in the youngest fetuses examined, but the final remodeling of the posterior anastomotic chain into two posterior spinal arteries occurred between 15th and 20th week of fetal life indicating that the vascularization of the anterior region of the spinal cord in the investigated period of fetal life was more advanced as compared with that of the posterior region. The capillary network of the gray matter in the youngest fetuses had the form of discrete glomerular plexuses supplied by groups of central arteries and mainly vascularizing the anterior horns. Successively, the plexuses fused to form a continuous system along the anterior columns and the system expanded to fully vascularize the posterior horns. The white matter in the earlier fetal period seemed to be partially avascular, later the density of capillaries vascularizing those areas was still much lower than in the gray matter. The veins showed considerably greater variability than the arteries, as far as their topography and distribution was concerned. High tortuosity characterized the superficial veins, especially in the younger fetuses, although the degree of tortuosity differed even between individual fetuses. Only anterior spinal and central arteries were usually accompanied by their venous counterparts, the other veins seemed to have no regular topographical relations with the arteries.     

女性乳房的应用解剖

目的研究女性乳房动脉和神经分布特征,为女性乳腺手术和乳房整形美容手术提供解剖学依据。方法对15具成年女性尸体30个乳房标本进行解剖,观测其动脉和神经的分支分布。结果①女性乳房血供由胸外侧动脉、胸廓内动脉、胸肩峰动脉和肋间动脉穿支提供。②第2～6肋间神经的外侧皮支和前皮支均支配女性乳房,分支走向呈"立体发散"模式达乳房腺体及皮肤。乳头和乳晕的神经以第4肋间神经为主。结论女性乳房手术应注意保护其动脉和神经。     

The sinuvertebral nerves at the craniovertebral junction: A microdissection study

Bogduk et al. ( 1988 , Spine 13:2–8) noted that the joints and ligaments at the cervico‐occipital region are susceptible to whiplash injury. The upper three cervical sinuvertebral nerves (SVNs) at the craniovertebral junction (CVJ) are thought to be responsible for mediating pain from the ligaments, dura mater, and soft tissues of the posterior cranial fossa and upper cervical column. The purpose of this study was to describe in detail the origin and course of the SVNs at C0–C1, C1–C2, and C2–C3 intervertebral levels and their anterior intraspinal distribution. A sample comprising 10 adult, 12 fetal (crown rump length = 155–250 mm), and three stillborn neonatal (n = 50 sides) embalmed cadaveric cervical spines was microdissected (Carl Zeiss, Jena, Germany, 8–40× magnification). A laminectomy of the cervical spine with an occipital craniectomy (seven adult and all fetal specimens) or a horizontal section of the intervertebral levels was performed (three adult specimens) to expose the craniocervical canal. In both adult and fetal specimens, all three cervical SVNs arose from two roots, a somatic root (from the spinal nerve or ventral ramus or both) and a sympathetic root (from the vertebral artery plexus or superior cervical ganglion). The C1 and C2 SVNs were variable in number. The C2 and C3 SVN innervated most of the structures at the CVJ as well as the basiocciput region. The C1 SVN supplied a very small part of the atlanto‐occipital joint area. The intraspinal courses of all three SVNs consisted of ascending and descending branches closely adherent to the arteries of the CVJ. They supplied the dura mater, the ligaments, adjacent joints, and soft tissues by tiny branches from the main branches. The detailed origins and course are described. Clin. Anat. 2013. © 2012 Wiley Periodicals, Inc.     

Arterial supply to the masseter muscle in the rat

Eighteen rats (thirty-six sides) were injected with red latex into the peripheral arteries through the left ventricle in the heart and fixed in 10% formalin to demonstrate the arterial architecture. According to the method of Yoshikawa et al. who proposed the lamination theory of this muscle, the latex injected specimens were dissected under a stereoscopic microscope. The masseter muscle in the rat was distributed by the masseteric branches of the facial, external carotid and dorsal branch of the infraorbital arteries as well as the transverse facial, masseteric and buccal arteries. This finding was essentially the same as observed on other species which included the dog, cat, crab-eating monkey, rabbit, cow and horse. However, the origin, course and distribution of the posterior deep temporal and masseteric arteries in the rat were considerably different from those of other species. Furthermore, since the way of development of the arteries and the subdivided muscles of the masseter muscle varies among species, the relationships between these arteries and the subdivided muscles seem to differ to some extent from species to species. Outline of the arterial system of the lateral aspect in the rat's head was shown in Fig. 1. The arteries and masseteric branches which were distributed to the subdivided muscles of the masseter muscle in the rat were as follows. 1) The first and second superficial and intermediate masseter muscles were distributed by the masseteric branches of the facial and external carotid arteries as well as the transverse facial, buccal and masseteric arteries. 2) The anterior portion of the deep masseter muscle was supplied by the masseteric branch of the facial, the masseteric and the buccal arteries. 3) The posterior portion of the deep masseter muscle received only the masseteric artery. 4) The maxillomandibular muscle was vascularized by the masseteric branch of the dorsal branch of the infraorbital and the buccal arteries. 5) the zygomaticomandibular muscle included only the masseteric artery.     

Fetal Anatomy of the Human Carotid Sheath and Structures In and Around It

The aim of this study was to find basic rules governing the morphological development of the typical neurovascular sheath. We carried out histological examination of 15 paraffin‐embedded mid‐term fetuses at 9–25 weeks of gestation (three fetuses each at 9, 12, 15, 20, and 25 weeks). As the result, the vagus nerve showed a high propensity to change its topographical relationship with the common carotid artery (CCA) during 9–20 weeks of gestation: that is, from a primitive ventral course to a final dorsal course. The adventitia of the great arteries, which was distinct from other fascial structures, became evident by 15 weeks. The carotid sheath appeared at and after 20 weeks: it was clearly separated from the prevertebral lamina of the deep cervical fasciae, but fused with the pretracheal lamina covering the strap muscles. Thus the carotid sheath, as well as the topographical relationships of structures within it, seems to become established much later than the prevertebral and pretracheal laminae of the deep cervical fasciae. However, the adventitia of the cervical great arteries consistently becomes evident much earlier than the sheath, and it seems to be regarded as one of the basic components of the fetal deep cervical fasciae. Anat Rec, 293:438–445, 2010. © 2010 Wiley‐Liss, Inc.     

Arterial supply of the soleus muscle: anatomical study of fifty lower limbs

Soft tissue defects of the lower limb are a formidable challenge to the plastic surgeon but a soleus muscle flap often provides the solution. Various types of soleus muscle flap have been described, based mainly on the vascular supply. The arterial blood supply of the soleus muscle was studied in 50 cadaveric lower limbs. The blood vessels and their branches to the muscle were dissected. The distance of the origin of the perforators was measured from fixed bony landmarks. Branches of the popliteal artery trunk, the posterior tibial artery, and the peroneal artery supplied the soleus muscle. The number of branches to the soleus muscle from these main arteries were analyzed. The medial part of the muscle was supplied throughout its length by perforators arising from the posterior tibial artery. This constant feature makes the medial part of the muscle reliable as a proximally or distally based flap. The average distances of the lower perforators arising from the posterior tibial artery were 6.5 cm, 11.6 cm, and 16.8 cm from the medial malleolus. The branches of the peroneal artery were mostly distributed in the upper half of the muscle. These large pedicles allow a composite transfer of the soleus muscle with the fibula. Lower perforators were demonstrated to arise from the peroneal artery in 60% of the limbs but the scarcity of perforators in this region limits the clinical usefulness of an inferiorly based lateral hemisoleus flap. The study demonstrates the distribution of arteries entering the soleus muscle and how the information may be used in the design of soleus muscle flaps. The average numbers of the perforators arising from the vessels and their distribution have been highlighted.     

经颈动脉三角上颈椎手术入路的应用解剖

经颈动脉三角显露上颈椎前方较充分，便于操作。长期以来，因解剖结构复杂，国内、外采用这一入路的报道资料很少。为提高该入路的可行性，本文通过对３２例经福尔马林固定的成人尸体在此入路进行了细致的解剖学观察，对测量数据作了统计学处理，探讨了该入路手术操作中应注意的一些重要问题。①动脉的寻找与结扎；②肌的处理；③椎体的显露、切除、取骨与植骨等。经临床应用观察，认为此入路暴露充分，安全、方便，无感染及后遗症，确具推广价值。     

经皮椎弓根螺钉技术的解剖学基础及其临床意义

目的：为经皮椎弓根螺钉技术提供解剖学基础并在此基础上分析经皮植入椎弓根螺钉较常规开放植入椎弓根螺钉临床应用的优点。方法：选用10具经防腐固定，在解剖显微镜下对胸腰段脊柱后部结构进行逐层解剖，重点观测脊神经后支及其分支、脊柱节段动静脉的后支的来源、走行以及分布规律。结果：脊神经后支的内侧支经骨纤维管下行沿途支配横突棘肌，支配下方小关节突、筋膜和韧带。外侧支向外下行走，沿途支配背部深层肌肉。节段动脉的后支在椎间孔的上外方绕向后下方，走行于脊神经的下方和下位脊椎上关节突的外方，分为内外两支穿行于腰部深层肌肉。节段静脉后支与同名动脉伴行，并与对侧、相邻节段同名静脉在棘突和横突部位构成静脉丛。结论：避免损伤脊神经后支和节段动静脉的后支并运用可视化操作系统的经皮椎弓根螺钉植入技术，是微创脊柱外科一种新的技术手段。