医学英语：腹壁与脐-1（文末PDF）

Embryology 胚胎学

      The abdominal wall begins to develop in the earliest stages of embryonic differentiation from the lateral plate of the embryonic mesoderm. At this stage, the embryo consists of three principal layers—an outer protective layer termed the ectoderm, an inner nutritive layer, the endoderm, and the mesoderm. 腹壁在胚胎分化的最早阶段开始发育，从胚胎中胚层的侧板开始发育。在这个阶段，胚胎由三个主要的保护层组成--外保护层称为外胚层、内营养层、内胚层和中胚层。

      The mesoderm becomes divided by clefts on each side of the lateral plate, which ultimately develop into somatic and splanchnic layers. The splanchnic layer with its underlying endoderm contributes to the formation of the viscera by differentiating into muscle, blood vessels, lymphatics, and connective tissues of the alimentary tract. The somatic layer contributes to the development of the abdominal wall. Proliferation of mesodermal cells in the embryonic abdominal wall results in the formation of an inverted U-shaped tube that in its early stages communicates freely with the extraembryonic coelom.中胚层被侧板两侧的裂隙分割，最终发展成体层和内脏层。内脏层及其下胚层通过分化为肌肉、血管、淋巴管和消化道的结缔组织，有助于内脏的形成。体细胞层有助于腹壁的发育。胚胎腹壁中胚层细胞增殖，形成倒U型管，早期与胚外体腔自由沟通。

      As the embryo enlarges and the abdominal wall components grow toward one another, the ventral open area, bounded by the edge of the amnion, becomes smaller. This results in the development of the umbilical cord as a tubular structure containing the omphalomesenteric duct, allantois, and fetal blood vessels, which pass to and from the placenta. By the end of the third month of gestation, the body wall has closed, except at the umbilical ring. Because the alimentary tract increases in length more rapidly than the coelomic cavity increases in volume, much of the developing gut protrudes through the umbilical ring to lie within the umbilical cord. As the coelomic cavity enlarges to accommodate the intestine, the latter returns to the peritoneal cavity so that only the omphalomesenteric duct, allantois, and fetal blood vessels pass through the shrinking umbilical ring. At birth, blood no longer courses through the umbilical vessels, and the omphalomesenteric duct has been reduced to a fibrous cord that no longer communicates with the intestine. After division of the umbilical cord, the umbilical ring heals rapidly by scarring.

      随着胚胎的增大和腹壁成分的相互生长，腹壁的开放区域，有界在羊膜边缘，变小了。这导致脐带发育为管状结构，包括脐肠系膜管、尿囊和胎儿血管，这些血管从胎盘进出。妊娠第三个月时，除脐带外，体壁已闭合。由于消化道的长度比体腔的体积增长更快，许多发育中的肠道通过脐带环突出到脐带内。随着体腔扩大以容纳肠道，后者返回腹腔，因此只有脐肠系膜管、尿囊和胎儿血管通过收缩的脐带。出生时，血液不再通过脐带血管流动，脐肠系膜管也已减少为纤维索，不再与肠沟通。脐带分裂后，脐带结疤愈合迅速。

Anatomy 解剖

      There are nine layers to the abdominal wall—skin, subcutaneous tissue, superficial fascia, external oblique muscle, internal

oblique muscle, transversus abdominis muscle, transversalis fascia, preperitoneal adipose and areolar tissue, and peritoneum

      腹壁-皮肤、皮下组织、浅筋膜、外斜肌、内斜肌、腹横肌、腹横筋膜、腹膜前脂肪和乳晕组织、腹膜共9层

Subcutaneous Tissues 皮下组织

      The subcutaneous tissue consists of Camper’s and Scarpa’s fascia. Camper’s fascia is the more superficial adipose layer that contains the bulk of the subcutaneous fat, whereas Scarpa’s fascia is a deeper denser layer of fibrous connective tissue contiguous with the fascia lata of the thigh. Approximation of Scarpa’s fascia aids in the alignment of the skin after surgical incisions in the lower abdomen.

      皮下组织由Camper 's和Scarpa 's筋膜组成。Camper筋膜是较浅的脂肪层，包含大部分皮下脂肪，而Scarpa筋膜是较深的纤维结缔组织层，与大腿阔筋膜相连。斯卡帕筋膜的近似值有助于在下腹手术切口后皮肤的对齐。

Muscle and Investing Fascias 肌肉和筋膜

      The muscles of the anterolateral abdominal wall include the external and internal oblique and transversus abdominis. These flat muscles enclose much of the circumference of the torso and give rise anteriorly to a broad flat aponeurosis investing the rectus abdominis muscles, termed the rectus sheath. The external oblique muscles are the largest and thickest of the flat abdominal wall muscles. They originate from the lower seven ribs and course in a superolateral to inferomedial direction. The most posterior of the fibers run vertically downward to insert into the anterior half of the iliac crest. At the midclavicular line, the muscle fibers give rise to a flat strong aponeurosis that passes anteriorly to the rectus sheath to insert medially into the linea alba. The lower portion of the external oblique aponeurosis is rolled posteriorly and superiorly on itself to form a groove on which the spermatic cord lies. This portion of the external oblique aponeurosis extends from the anterior superior iliac spine to the pubic tubercle and is termed the inguinal or Poupart’s ligament. The inguinal ligament is the lower free edge of the external oblique aponeurosis posterior to which pass the femoral artery, vein, and nerve and the iliacus, psoas major, and pectineus muscles. A femoral hernia passes posterior to the inguinal ligament, whereas an inguinal hernia passes anterior and superior to this ligament. The shelving edge of the inguinal ligament is used in various repairs of inguinal hernia, including the Bassini and the Lichtenstein tension-free repair.

      腹壁前外侧肌包括腹外斜肌、腹内斜肌和腹横肌。这些扁平的肌肉包围了躯干的大部分周长，并在前面形成一个覆盖腹直肌的宽阔扁平腱膜，称为腹直肌鞘。外斜肌是腹壁扁平肌中最大最厚的。它们起源于下七肋，沿上外侧到下内侧的方向行进。最后面的纤维垂直向下插入到髂嵴的前半部分。在锁骨中线，肌肉纤维产生一个扁平的强直腱膜，该腱膜向前穿过直肌鞘，向内侧插入白线。外斜肌腱膜的下半部分向后和向上滚动，形成一个凹槽，精索位于其上。外斜肌腱膜的这一部分从髂前上棘一直延伸到耻骨结节，称为腹股沟韧带或腹侧韧带。腹股沟韧带是后外侧斜腱膜的下游离缘，穿过股动脉、静脉、神经和髂骨、腰大肌和耻骨肌。股疝通过腹股沟韧带的后部，而腹股沟疝通过该韧带的前部和上部。腹股沟韧带的支架边缘用于腹股沟疝的各种修补术，包括Bassini和Lichtenstein无张力修补术。

      The internal oblique muscle originates from the iliopsoas fascia beneath the lateral half of the inguinal ligament, from the anterior two thirds of the iliac crest and lumbodorsal fascia. Its fibers course in a direction opposite to those of the external oblique—that is, inferolateral to superomedial. The uppermost fibers insert into the lower five ribs and their cartilages. The central fibers form an aponeurosis at the semilunar line, which, above the semicircular line (of Douglas), is divided into anterior and posterior lamellae that envelop the rectus abdominis muscle. Below the semicircular line, the aponeurosis of the internal oblique muscle courses anteriorly to the rectus abdominis muscle as part of the anterior rectus sheath. The lowermost fibers of the internal oblique muscle pursue an inferomedial course, paralleling that of the spermatic cord, to insert between the symphysis pubis and pubic tubercle. Some of the lower muscle fascicles accompany the spermatic cord into the scrotum as the cremasteric muscle.

      内斜肌起源于腹股沟韧带下半部的髂腰肌筋膜髂嵴和腰背筋膜的前三分之二。它的纤维方向与外界相反斜的，即从下外侧到上内侧。最上面的纤维插入下面的五根肋骨及其软骨。中央纤维在半月线形成腱膜，(道格拉斯的)半月线以上，分为前片和后片，包裹腹直肌。半月线以下线，内斜肌腱膜向前延伸至腹直肌，作为腹直肌前部的一部分直肌鞘。内斜肌最下面的纤维沿着下腹部走行，平行精索，插入耻骨联合和耻骨结节之间。一些下肌束伴随着精索进入阴囊作为提睾肌。

      The transversus abdominis muscle is the smallest of the muscles of the anterolateral abdominal wall. It arises from the lower six costal cartilages, spines of the lumbar vertebra, iliac crest, and iliopsoas fascia beneath the lateral third of the inguinal ligament. The fibers course transversely to give rise to a flat aponeurotic sheet that passes posterior to the rectus abdominis muscle above the semicircular line and anterior to the muscle below it. The inferiormost fibers of the transversus abdominis originating from the iliopsoas fascia pass inferomedially along with the lower fibers of the internal oblique muscle. These fibers form the aponeurotic arch of the transversus abdominis muscle, which lies superior to Hesselbach’s triangle and is an important anatomic landmark in the repair of inguinal hernias, particularly Bassini’s operation and Cooper’s ligament repairs. Hesselbach’s triangle is the site of direct inguinal hernias and is bordered by the inguinal ligament inferiorly, lateral margin of the rectus sheath medially, and inferior epigastric vessels laterally. The floor of this triangle is composed of transversalis fascia.

      腹横肌是腹前外侧壁最小的肌肉。它产生于腹股沟外侧三分之一以下的六个肋软骨、腰椎棘、髂嵴和髂腰肌筋膜韧带。纤维横行形成一个扁平的腱膜片，从腹直肌后方穿过半规线以上和半环线以下的肌肉前面的肌肉。腹横肌最下面的纤维起源于髂腰肌筋膜，与内斜肌的下纤维一起下穿。这些纤维构成了腹横肌的腱膜弓，它位于Hesselbach三角的上方，是腹股沟疝修复，尤其是Bassini手术和Cooper韧带修复的重要解剖标志。Hesselbach三角是腹股沟直疝的部位，在腹股沟韧带的下方，外侧腹直肌鞘内侧边缘，腹壁下血管外侧边缘。这个三角形的底部由腹横筋膜组成。

      The transversalis fascia covers the deep surface of the transversus abdominis muscle and, with its various extensions, forms a complete fascial envelope around the abdominal cavity. This fascial layer is regionally named for the muscles that it covers—for example, the iliopsoas fascia, obturator fascia, and inferior fascia of the respiratory diaphragm. The transversalis fascia binds together the muscle and aponeurotic fascicles into a continuous layer and reinforces weak areas where the aponeurotic fibers are sparse. This layer is responsible for the structural integrity of the abdominal wall and, by definition, a hernia results from a defect in the transversalis fascia.

      腹横筋膜覆盖腹横肌的深表面，随着它的各种延伸，在腹腔周围形成一个完整的筋膜包膜这个筋膜层以它所覆盖的肌肉命名例如，髂腰肌筋膜，闭孔筋膜，和呼吸隔膜的下筋膜。腹横筋膜将肌肉和筋膜束连接成一个连续的层，加强筋膜纤维稀疏的薄弱区域。这一层负责腹壁的结构完整性，根据定义，疝是由腹横筋膜的缺陷引起的。

      The rectus abdominis muscles are paired muscles that appear as long, flat triangular ribbons wider at their origin on the anterior surfaces of the fifth, sixth, and seventh costal cartilages and the xiphoid process than at their insertion on the pubic crest and pubic symphysis. Each muscle is composed of long parallel fascicles interrupted by three to five tendinous inscriptions, which attach the rectus abdominis muscle to the anterior rectus sheath. There is no similar attachment to the posterior rectus sheath. These muscles lie adjacent to each other, separated only by the linea alba. In addition to supporting the abdominal wall and protecting its contents, contraction of these powerful muscles flexes the vertebral column.

      腹直肌是成对的肌肉，在第五，第六和第七肋软骨和剑突的前表面，它们的起源处比在耻骨嵴和耻骨联合的插入处看起来更宽，像长而平的三角带。每块肌肉由平行的长束组成，由三到五个腱状的铭文打断，这些铭文将腹直肌连接到前腹直肌鞘。后直肌鞘没有类似的附着。这些肌肉彼此相邻，仅由白线隔开。除了支撑腹壁和保护其内容物，这些强有力的肌肉的收缩使脊柱弯曲。

      The rectus abdominis muscles are contained within the rectus sheath, which is derived from the aponeuroses of the three flat abdominal muscles. Superior to the semicircular line, this fascial sheath completely envelops the rectus abdominis muscle,with the external oblique and anterior lamella of the internal oblique aponeuroses passing anterior to the rectus abdominis and aponeuroses from the posterior lamella of the internal oblique muscle, transversus abdominis muscle, and transversalis fascia passing posterior to the rectus muscle. Below the semicircular line, all these fascial layers pass anterior to the rectus abdominis muscle, except the transversalis fascia. In this location, the posterior aspect of the rectus abdominis muscle is covered only by transversalis fascia, preperitoneal areolar tissue, and peritoneum.

      腹直肌包含在腹直肌鞘内，腹直肌鞘来源于腹直肌和腹直肌的腱膜腹部肌肉扁平。优于半环线，筋膜鞘完全包裹腹直肌，内斜腱膜的外斜板和前板通过腹直肌前方内斜肌、腹横肌和腹横肌后板的腱膜通过直肌后方的筋膜。在半环线以下，除横筋膜外，所有这些筋膜层都通过腹直肌的前方。在这个位置，腹直肌的后部是仅被横筋膜、腹膜前乳晕组织和腹膜覆盖。

      The rectus abdominis muscles are held closely in apposition near the anterior midline by the linea alba. The linea alba consists of a band of dense, crisscrossed fibers of the aponeuroses of the broad abdominal muscles that extends from the xiphoid to the pubic symphysis. It is much wider above the umbilicus than below, thus facilitating the placement of surgical incisions in the midline without entering the right or left rectus sheath.

      腹直肌被白线紧紧地贴在前中线附近。白线由一束密集的、纵横交错的宽腹肌腱膜纤维组成，从剑状肌延伸到耻骨联合。它在脐上比在脐下要宽得多，因此便于在中线上放置手术切口而不进入右或左直肌鞘。

Preperitoneal Space and Peritoneum 腹膜前间隙和腹膜

      The preperitoneal space lies between the transversalis fascia and parietal peritoneum and contains adipose and areolar tissue. Coursing through the preperitoneal space are the following: 腹膜前间隙位于腹横筋膜和腹膜壁之间，包含脂肪和乳晕组织。通过腹膜前间隙的过程如下:

• 1. Inferior epigastric artery and vein
• 2. Medial umbilical ligaments, which are the vestiges of the fetal umbilical arteries
• 3. Median umbilical ligament, which is a midline fibrous remnant of the fetal allantoic stalk or urachus
• 4. Falciform ligament of the liver, extending from the umbilicus to the liver
• 1. 腹壁下动脉和静脉
• 2. 中间的脐韧带，这是胎儿脐动脉的残余
• 3. 脐中韧带，是胎儿尿囊柄或脐尿管的中线纤维残体
• 4. 镰状韧带肝脏的镰状韧带，从脐部延伸到肝脏

      The round ligament, or ligamentum teres, is contained within the free margin of the falciform ligament and represents the obliterated umbilical vein, coursing from the umbilicus to the left branch of the portal vein. The parietal peritoneum is the innermost layer of the abdominal wall. It consists of a thin layer of dense, irregular connective tissue covered on its inner surface by a single layer of squamous mesothelium.

      圆韧带位于镰状韧带的游离边缘内，代表消失的脐静脉，从脐流向门静脉左支(图45-6)。腹膜壁层是腹壁的最内层。它由一层致密的、不规则的结缔组织构成，在它的内表面覆盖着一层鳞状的间皮层。