What is an anterior abdominoplasty (abdominoplasty)?

• Story

The main cause of stretching of the muscular-fascial layer and weakness of the skin of the anterior abdominal wall is pregnancy. The degree of residual changes can vary from a rounded protruding lower abdomen to an extensive diastasis between the rectus muscles combined with widespread stretch marks and the formation of an "apron". Time and significant fluctuations in body weight further reduce skin tone and increase symptoms.

In case of severe contour disorders, only surgery can significantly improve the situation.

At the beginning of the 20th century, abdominoplasty was performed only in the form of excision of the skin-fat fold in the lower abdomen (panniculectomy). The first panniculectomy was described by Kelly in 1899 and consisted of excision of a block weighing 7450 g, measuring 9 0 x 3 1 cm and 7 cm thick. Subsequently, various techniques for plastic surgery of the anterior abdominal wall were developed. Many of these methods are of only historical interest. Others contain elements that subsequently formed the basis of modern abdominoplasty.

• Anatomy of the anterior abdominal wall

The anterior abdominal wall is rhomboid and is limited by the xiphoid process and the edge of the costal arch above, the oblique abdominal muscles, the edge of the iliac bones and the inguinal ligament below. The contours of the anterior abdominal wall vary depending on gender, age and body weight. The range of contours can change from retraction in asthenics to a slight convexity in hypersthenics and sagging skin-fat folds in obesity.

The umbilicus is the most visible landmark on the anterior abdominal wall. It is located below the midpoint of the line connecting the xiphoid process to the pubic bone. The location of the umbilicus is relatively constant: between the waist line and the line connecting the anterior superior iliac spines.

• Superficial layer of soft tissue

The skin of the abdomen is quite mobile, except for the area located along the midline above the navel. The superficial fascia below the navel is divided into two well-defined plates. One of them, the superficial one, is connected to the superficial layer of subcutaneous fat, and the superficial vessels of the anterior abdominal wall are located on it. The deep leaf of the superficial fascia is aponeurotic in nature and fuses with the inguinal (pupart) ligament below. With an increase in the layer of subcutaneous fat, this leaf becomes so dense that it can sometimes be mistaken for the aponeurosis of the external oblique muscle of the abdomen.

The subcutaneous fat tissue of the anterolateral parts of the abdomen is distinguished by the fact that it contains numerous connective tissue bridges. They are located in different planes and divide the fat tissue into lobes, layers and strata of varying length and thickness.

Unlike these zones, along the white line of the abdomen and in the navel area, the superficial fascia is not expressed. However, there are quite a lot of connective tissue bridges going to the skin from the aponeurosis of the white line and the umbilical ring, as a result of which the subcutaneous tissue of the right and left halves of the abdominal wall is often divided by this fibrous septum almost along the entire length of the abdomen. Accordingly, the skin above the white line and the navel is less mobile.

• Muscular-aponeurotic layer

The muscular-aponeurotic layer of the anterior abdominal wall consists of several layers. Like an elastic band, it envelops the contents of the abdominal cavity, and its tone helps maintain normal intra-abdominal pressure. The muscular-fascial system of the anterior abdominal wall consists of four paired muscles and their aponeurotic extensions. The external oblique, internal oblique, and transverse muscles are lateral muscles that converge medially into one aponeurosis. The sheets of the latter form strong sheaths for the vertically located rectus abdominis muscles. These sheaths, intersecting with each other, form the white line of the abdomen.

On the surface of the rectus muscles are pyramidal muscles, which are triangular in shape and small in size. They start from the pubic bones and are woven into the white line. Halfway between the navel and the pubis, the posterior edge of the aponeurosis of the rectus muscles ends with the so-called arcuate line. Below it, the deep surface of the transverse muscles is covered by a fairly strong transverse fascia.

In general, the muscular-aponeurotic layer of the anterior abdominal wall can be considered as a single complex consisting of three groups of muscles, the common tendon of which is the white line of the abdomen. Its stretching is counteracted by the contraction of the rectus abdominis muscles.

• Vascular and nervous supply of the anterior abdominal wall

The blood supply and innervation of the anterior abdominal wall are discussed in detail in Part II. In this section, they are considered only in relation to the operation of plastic surgery of the anterior abdominal wall.

The main contribution to the blood supply of the mid-zone of the anterior abdominal wall is made by the superior and inferior deep epigastric arteries. The superior epigastric artery lies on the deep leaf of the rectus sheath, arising as a continuation of the thoracic artery. It descends and anastomoses with the inferior epigastric artery, which is a branch of the external iliac artery. The inferior deep epigastric artery appears proximally from the inguinal ligament and ascends obliquely anteriorly and toward the umbilicus. It pierces the transversalis fascia and enters the rectus sheath anterior to the semilunar line.

The anterolateral parts of the anterior abdominal wall receive their blood supply from the lateral branches of the six intercostal and four lumbar arteries and the deep circumflex iliac artery. These arteries pass together with the intercostal, iliohypogastric and ilioinguinal nerves, penetrate laterally the sheaths of the rectus muscles and freely anastomose with the epigastric system.

Thus, normally the main sources of blood supply to the superficial tissues of the anterior abdominal wall are directed from the periphery to the center (the navel area) and in the opposite direction (from the navel area in radial directions) due to pronounced periumbilical perforating arteries. After surgery with mobilization of the skin-fat flap over a large area, its blood supply is provided from the periphery to the center.

Lymphatic system. Lymphatic vessels are divided into those draining the supra-umbilical part, which go to the thoracic part of the axillary nodes, and those draining the area below the navel with outflow to the superficial inguinal lymph nodes. The lymphatic vessels of the liver communicate through the round ligament with the lymphatic vessels of the anterior abdominal wall.

Innervation. The anterior abdominal wall is innervated by the lateral and anterior branches of The-u and Li. The lateral branches enter the subcutaneous fat along the midaxillary line, bend around and are preserved during most operations. The anterior branches enter the tissue of the rectus muscles, and are usually damaged during abdominoplasty.