Variations in collateral contributions to the blood supply to the sternum

The blood supply of the sternum plays a major role in healing of the sternum after sternotomy. The sternal blood supply is derived mainly from the medial horizontal branches of the internal thoracic artery (ITA). The ITA is usually described as giving off sternal, anterior intercostal and perforating branches supplying their respective areas. The aim of the present study was to describe variations in the arterial branching pattern of collateral contributions to the sternum. The study was conducted on 30 fresh specimens of anterior thoracic wall in which cellulose acetate butyrate was injected into the ITA. The branches of the ITA in the first to sixth intercostal spaces were dissected and any additional artery supplying the sternum in each intercostal space was observed. In the present study, the ITA gave off non-collateral branches - sternal, anterior intercostal and perforating. The ITA was also found to have branches which divided into two to supply two destinations which could establish collateral flow to the sternum: (1). A sterno-intercostal branch (1-12 mm in length) divided and diverged in a Y or T shape. The medial limb supplied the sternum and the lateral limb supplied the adjoining thoracic wall, anastomosing with the terminal part of the posterior intercostal artery. (2). A sterno-perforating branch supplied the sternum either anteriorly or posteriorly before perforating and supplying the pectoral region and anastomosing with the thoracoacromial artery. This study reinforces the practice of ligating branches of the ITA close to its trunk as they have the potential to develop collateral blood supply. In the present study the posterior intercostal artery was at times found to supply the sternum directly or via its collateral branch and was named the persistent posterior intercostal artery.     

Factors influencing the diameter of human anterior and posterior intercostal arteries

At present, there have not been any detailed studies examining the size relationships of the intercostal arteries. This study was carried out to investigate the relationship between the vessel lumenal diameter of ipsilateral, paired anterior and posterior IC arteries, as well as with the length of the IC space supplied by each artery. Samples were collected from the second‐sixth anterior and posterior IC arteries near their site of origin, and the lengths of the corresponding IC spaces were measured in 42 cadavers. Lumenal diameters of both the anterior and posterior IC arteries at consecutive IC space closely followed second degree polynomial regression models (R² = 0.9655, and R² = 0.9741, respectively), and reached maximum size at the fifth IC space, which was found to be the longest of the IC spaces. No direct relationship was observed between diameters of the paired anterior and posterior IC arteries, although there was a trend for the larger anterior IC arteries to be paired with the larger posterior IC arteries. The calculated rate of blood flow at each IC artery was approximately two‐fold greater in males than in females. These results suggest that the length of the IC space, and hence the extent of the thoracic wall supplied, is a major factor in determining the diameter of both anterior and posterior IC arteries. Since COPD is such a prevalent disease, this study also examined its influence on the IC arteries, and found that the posterior IC arteries are significantly larger among afflicted subjects. Clin. Anat. 28:219–226, 2015. © 2014 Wiley Periodicals, Inc.     

Bifid Rib: Anatomical Considerations in Three Cases

The present study involved a detailed investigation of 3 cases of bifid rib, focusing on anatomical features, and classified them into 2 types. The bifid ribs were in the right fourth rib of all 3 male cadavers. The upper intercostal spaces of the fourth bifid rib were considerably narrowed, whereas the lower intercostal spaces were widened. Although the size and shape of the bifid space between the upper and lower divisions of the bifid rib were different, the intercostal muscles were present in the bifid space in all cases. The third anterior intercostal artery from the internal thoracic artery supplied the bifid space in all cases. In 2 cases, the fourth intercostal nerve ran along the inferior margin of the fourth bifid rib and innervated the muscles of the bifid space. In the third case, there was another branch from the third intercostal nerve supplying the muscles of the bifid space as well as the fourth intercostal nerve. The bifid ribs are associated with other diseases or develop accidentally or sporadically. Knowledge of this malformation is needed for the differential diagnosis with other diseases, such as a chest wall tumor or costal fracture.     

胸内侧皮瓣血管的巨微解剖

在手术显微镜下,解剖了成人尸体50侧,对胸内侧区皮瓣血管源进行了研究。胸廓内动脉在上4个肋间隙发出的穿动脉中,以第Ⅱ穿动脉的出现率最高,平均管径最粗,分布面积也最大。进行胸内侧皮瓣吻合血管移植时,宜首选第Ⅱ穿动脉作为血管蒂。第Ⅰ穿动脉的分布面积和中心分布区,均大于第Ⅲ或第Ⅳ穿动脉,是第二选择。胸廓内动脉跨越了几个肋间隙,其中,第2肋间隙位置较浅,距胸骨缘较远,较其他肋间隙宽,这些有利于以第Ⅱ穿动脉,甚至连同一段胸廓内动脉,作为皮瓣血管蒂的采取。如果切除一段第2肋软骨,以胸廓内动脉连同第Ⅰ、Ⅱ穿动脉为血管蒂,可以扩大皮瓣的采取范围。根据穿动脉的起源、位置、管径、浅出点、行程、分布区范围和吻合情况等,讨论了采取吻合血管胸内侧皮瓣时应注意的问题。     

胸后壁胸膜腔穿刺安全区的定位

目的探究胸后壁第六至第九肋间隙肋间神经和肋间后血管的走行及位置关系,为临床在胸后壁行胸膜腔穿刺确定在肋间隙进针的安全区域。方法在32具成人尸体上,解剖胸后壁第六至第九肋间隙的肋间神经和肋间后血管,观察它们的走行及位置关系,测量肋间神经和肋间后动脉、静脉各自的分叉点及各自的下支与下位肋上缘交点距后正中线和肩胛线的距离,并进行统计学分析。结果肋间神经、血管在排列和分布上呈现一定的规律。结论根据肋间神经和肋间后血管在胸后壁的走行和位置状况可确定胸腔穿刺术的安全进针区。     

An anatomical study of the relationship between the sympathetic trunk and intercostal veins of the third and fourth intercostal spaces during thoracoscopy

The complexity of the anatomy of the sympathetic trunk and intercostal veins in the third and fourth intercostal space may lead to intraoperative or postoperative bleeding. The purpose of this study was to investigate the anatomical variations of the sympathetic trunk and intercostal veins in the third and fourth intercostal spaces. The size and crossing type of veins in the third and fourth intercostal spaces in 44 Korean patients with palmar hyperhidrosis were analyzed. We classified intercostal veins by their size (small, medium, and large) and crossing type (anterior or posterior to sympathetic nerve). Large intercostal veins susceptible to bleeding were found in 36.4 and 68.2% of patients in the right third and fourth intercostal spaces, respectively and in 2.3 and 4.5% of left third and fourth intercostal spaces, respectively. More than 80% of the left third and fourth intercostal veins were small. Anterior crossing intercostal veins, which often cause problems at the third and fourth right intercostal spaces, were found in 27.3% (third) and 15.9% (fourth). However, there were only two cases of anterior crossing veins on the left side. Large anterior crossing veins were found only on the right side. In conclusion, surgical procedures of the right sympathetic ganglia may have increased risks due to a higher frequency of large anterior crossing intercostal veins. Careful dissection is necessary to decrease the incidence of intraoperative or postoperative bleeding. Clin. Anat. 23:702–706, 2010. © 2010 Wiley‐Liss, Inc.     

肺移植中支气管动脉的应用解剖

目的：提供肺移植支气管动脉吻合术有关的参考资料。方法：于肺根处逆向解剖了２２具成人尸体的支气管动脉，观察其外径和行程规律。结果：左支气管动脉起于主动脉弓下缘→左支气管上缘，和／或起于胸主动脉前壁→左支气管下缘，外径均为１．７ｍｍ。右支气管动脉主要起于右侧肋间动脉→右支气管后壁，外径２．０ｍｍ，是右肺、支气管的主要营养动脉；其次起于主动脉弓下缘、胸主动脉前壁→右支气管下缘，也可以是合干支气管动脉（出现率约１／３）的右支。结论：支气管动脉与胸廓内动脉吻合是肺移植血供重建的术式，但对于“后壁”右支气管动脉，宜将其肋间后动脉主干与受体的相应动脉吻合     

Vascularization of the human adult sternum (author's transl)

The study of the vascularization of the sternum allows to individualise the vascular pedicles, the anterior and posterior peripheral sternal networks and the intrasternal vascularization. 1. The numerous vascular pedicles of the sternum all come from the internal mammary arteries. The postero-superior and postero-inferior sternal arteries of one simple intercostal space or of contiguous spaces are anastomosed by systems of latero-sternal, retroarticular and retro-sternal arches. From these arches come vessels which go directly to the sternum or which form the posterior peripheral sternal network. The anterior sternal branches of perforating arteries form arches or go directly to the anterior peripheral sternal network or to the sternum. The veins are less anastomosed than the arteries and therefore their arches are less distinct. 2. The anterior and posterior peripheral sternal networks are especially developed with respect to the lower half of the body of the sternum at the level of the 4th and 5th intercostal spaces. The posterior network is more developed than the anterior network. The arteries often have a spiral course, their anastomoses occur with their contralateral and homolateral homologues. The veins, which are of larger calibre than the arteries, design a denser and more irregular network. 3. The intra-skeletal vascularization, tributary of the peripheral networks, arches and branches of the internal mammary vessels, includes a network of the compact bone and a medullary network. The network of the compact bone, situated in one plane, is composed of polyhedral elongated meshes, according to the large axe of the sternum. The medullary network may be divided into a sub-cortical and a centro-medullary part. The sub-cortical part is composed of a peripheral zone and a more central zone. The totality of the intramedullary network includes a few fine arteries, an interadipocytary network, which is very developed and is variable in form. It also include sinuses of increasing order connected into the venous system, into the network of the compact bone, or into the large trans-cortical veins, which are drained by the peripheral sternal networks or by the collateral veins or the internal mammary system.     

Thoracic paravertebral spread using two different ultrasound‐guided intercostal injection techniques in human cadavers

The continuity between the intercostal and paravertebral space has been established by several studies. In this study, the paravertebral spread of a colored dye was attempted with two different ultrasound‐guided techniques. The posterior area of the trunk was scanned with a linear probe between the level of the fifth and the seventh thoracic vertebrae in eleven embalmed human cadavers. In the first technique, the probe was placed transversely below the inferior margin of the rib, and a needle was inserted between the internal intercostal membrane and the pleura. In the second technique, the probe was placed longitudinally at the intercostal space 5 cm lateral to the spinous processes, and the needle was inserted between the internal intercostal membrane and the pleura. In both techniques, 1 ml of methylene blue was injected, and both the intercostal and paravertebral spaces were prepared. In total, 33 injections were performed: 19 with the transverse technique and 14 with the longitudinal technique. Successful spread of the dye to the thoracic paravertebral space was recorded in 89.5% cases using the transverse technique and 92.8% cases using the longitudinal technique. No intrapleural spread of the dye was recorded in either technique. Ultrasound‐guided injection into the intercostal space may offer an alternative approach to the thoracic paravertebral space. Clin. Anat. 23:840–847, 2010. © 2010 Wiley‐Liss, Inc.     

Neurovascular anatomy and variation in the fourth, fifth, and sixth intercostal spaces in the mid-axillary line: a cadaveric study in respect of chest drain insertion

Chest drains are normally inserted in the fifth intercostal space in the mid-axillary line. The classical technique for chest drain insertion involves locating the drain in an interspace just superior to the inferior rib, so as to avoid the neurovascular bundle. While teaching thoracic wall anatomy on cadavers, considerable variation was noted in the position of the neurovascular bundles, frequently lying well away from the generally accepted subcostal groove. We endeavoured to perform a comprehensive cadaveric study of the neurovascular relationships in the mid-axillary line in the fifth and adjacent spaces to try to describe a 'Safe Zone' for drain insertion to minimise damage to associated structures. The idea that the neurovascular bundle is safely protected in the subcostal groove should be dispelled, as should the concept that there is nothing to damage in the zone immediately superior to the inferior rib. Clinicians should be aware that the Safe Zone is narrower than hitherto appreciated and should be between 50-70% of the way down an interspace to avoid the variably positioned superior intercostal neurovascular bundle and the inferior collateral artery.     

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。     

内科胸腔镜在提高胸腔积液诊断率中的价值

目的评价内科胸腔镜在提高胸腔积液病因诊断中的价值及内科胸腔镜的检查时机。方法连续收集渗出性胸腔积液患者311例,其中男性194例,女性117例;年龄17～90岁,平均年龄58.3岁。评估胸腔积液细胞学对恶性胸水的诊断率。对27例经胸水细胞学未能诊断的患者和2例胸水细胞学恶性胸腔积液但未准确分型的患者进行了内科胸腔镜检查,评估胸腔镜检查联合胸水细胞学检查对胸腔积液诊断率及恶性胸水的准确诊断率的影响。结合不同次数的胸腔积液细胞学的阳性率及相关支出,评估内科胸腔镜的检查时机。结果311例渗出性胸腔积液患者经胸水细胞学诊断恶性胸腔积液的患者为80例;231例胸水细胞学未确诊的患者结合各自情况,经过内科胸腔镜检查和/或支气管镜、或肺动脉CT造影等检查,并结合临床资料系统分析后,诊断如下:恶性胸腔积液106例,良性胸腔积液91例,未确诊病例34例。胸水细胞学检查的确诊率为28.9%(80/277)。29例接受了内科胸腔镜检查患者中,25例患者直接确诊,诊断率为86.2%。内科胸腔镜检查使该组病例的确诊率提高到37.9%(105/277),与单纯胸腔积液细胞学检查结果比较差异有统计学意义(P=0.024)。3次及以上的胸腔积液细胞学检查不能较2次胸腔积液细胞学检查提高更多的诊断率(P=0.156),且其支出超过内科胸腔镜的支出。结论内科胸腔镜不仅较胸腔积液细胞学检查能提高恶性胸腔积液的诊断率,更能提高胸腔积液总体诊断率。对2次胸腔积液细胞学检查无结果者,如无禁忌证,应积极进行内科胸腔镜检查。     

Superior phrenic artery: an anatomic study

The majority of anatomical textbooks offer very little information concerning the anatomy and distribution of the superior phrenic artery (SPA). However, in the last decade, a number of reports have appeared with reference to the transcatheter arterial chemoembolization of the collateral arterial supply of hepatic carcinoma (HC). Considering the potential role of the SPA as a source of collateral blood supply to HC, the aim of this study was to identify the origin and distribution of the SPA. One hundred formalin-fixed adult cadavers with no evidence of significant gross diaphragmatic pathology were examined. The right SPA originated from the aorta (R1) in 42%, as a branch of the proximal segment of the 10th intercostal artery (R2) in 33%, and as a branch of the distal segment of the 10th intercostal artery (R3) in 25%, of the specimens. The left SPA originated from the aorta (L1) in 51%, from proximal segment of the left 10th intercostal artery (L2) in 40%, and from the distal segment of the left 10th intercostal artery (L3) in 9%, of the specimens. In types R1, R2, L1 and L2 the SPA terminated, after a short course, within the medial and posterosuperior surfaces of the thoracic diaphragm and diaphragmatic crura. Conversely, in types R3 and L3 the lateral origin of the SPAs confined the ultimate distribution of the vessels to the posterior surface of the diaphragm. These findings could provide a better understanding of the anatomy and distribution of the arterial supply of the diaphragm and the potential involvement of the right SPA as an extrahepatic collateral artery developed in HC.     

The arterial supply of the cervical and thoracic spinal muscles and overlying skin: Anatomical study with implications for surgical wound complications

Postoperative spinal wound dehiscence is a significant complication following the posterior midline approach. It is postulated that this approach disrupts the vasculature supplying the paraspinal muscles and overlying skin. Although the spinal vasculature has been investigated previously, the smaller arterioles have not been described in the context of the posterior midline approach. Eight cadaveric neck and posterior torso specimens were dissected after injection with a radio‐opaque lead oxide mixture and subsequent radiographs taken were analyzed. The deep cervical, vertebral, superficial cervical, and occipital arteries consistently supplied the cervical paraspinal muscles. The latter two arteries also vascularized the overlying skin. The deep cervical arteries were found to be located lateral to the C3 to C6 vertebrae, vulnerable to damage with the posterior approach. In the thoracic region, the superior and posterior intercostal arteries consistently supplied the spinal muscles. In all specimens, two small anastomotic vessels posterior to the laminae were found connecting the intercostal artery perforators. Both the arterial perforators and their anastomotic channels were situated in the surgical field and susceptible to damage with the posterior approach. It is likely that the disruption in spinal vasculature contributes to the multifactorial problem of wound dehiscence with the posterior midline approach. Clin. Anat. 26:584–591, 2013. © 2012 Wiley Periodicals, Inc.     

多血管神经蒂腹内斜肌瓣修复面瘫的解剖学基础

目的：为多血管神经蒂腹内斜肌瓣修复晚期面瘫提供解剖学基础。方法：在３６侧成尸标本上,对腹内斜肌的形态、血供及神经支配进行解剖观测。结果：腹内斜肌中部上１／２肌腹主要由第１１肋间神经支配,下１／２肌腹主要由肋下神经支配。上１／２肌腹的血供６６．７％来自第１１肋间后动脉,３３．３％来自旋髂深动脉的髂嵴支;下１／２肌腹的血供主要来自旋髂深动脉的腹壁肌支。第１１肋间神经、肋下神经在腋后线横径分别为２．２ｍｍ和２．４ｍｍ,入肌点距腋后线长分别为１３．３ｃｍ和１３．８ｃｍ。第１１肋间后动脉在腋后线外径为１．７ｍｍ,入肌点距腋后线长为１３．１ｃｍ;旋髂深动脉腹壁肌支和髂嵴支的起始外径分别为１．３ｍｍ和１．８ｍｍ,入肌点至起点长分别为５．１ｃｍ和８．６ｃｍ。结论：吻合多血管神经腹内斜肌瓣移植可全面修复晚期面瘫     

翻转胸廓内动脉冠状动脉旁路术的实验研究

目的 研究翻转胸廓内动脉用于冠状动脉旁路术的可行性。方法 对１０具成人尸体胸廓内动脉的特性进行观察,并测量左、右各助间点到ＩＴＡ起点、冠状动脉左前降支中点的距离。结果 于近端切断胸廓内动脉可以保证该动脉逆向供血,血供来源于下位肋间动脉、肌隔动脉和腹壁上动脉。左侧第３肋间以下的各肋间中点,到ＩＴＡ起点处的长度明显长于其到冠状动脉左前降支中点的距离;右侧第４肋间以下的各肋间中点,到ＩＴＡ起点处的长距离     

Clinical anatomy of internal thoracic artery branches

The broad clinical utilization of the internal thoracic artery (ITA), including the role of its branches in supplying circulation to the sternum, requires explicit anatomic knowledge of this vessel. Fifty‐six ITAs (28 right, 28 left) were dissected from their point of origins after injection with a mixture of contrast medium and latex after perfusion with saline and immersion in 4% formaldehyde. All ITA branches were studied according to their course, size, and distribution within intercostal spaces with the aid of an operating microscope. The branches were divided in two main groups: proper (solitary) branches and common trunks. The proper branches consisted of four types: sternal, perforating, intercostal, and mediastinal. The four types of common trunks were: sternal/perforating, sternal/intercostal, perforating/intercostal, sternal/perforating/intercostal. Points of most frequent origin from main trunk of the vessel were established for each type. Mean external diameter of proper branches was 0.72 mm and common trunks was 1.06 mm. Mean length of common trunks was 3.0 mm. Those parameters (adequate diameter and length) allow for ligation of the common trunks close to the ITA so that their points of division can be preserved. This fact is crucial for creation of collateral blood supply to the sternum after bilateral ITA mobilizations. Clin. Anat. 12:307–314, 1999. © 1999 Wiley‐Liss, Inc.