Abdominal wall

What bounds the abdominal wall superiorly?

The abdominal wall is bounded superiorly by the xiphoid process and costal margins.

What are the three main layers of the abdominal wall?

Skin, muscles and their associated deep fascias, and parietal peritoneum.

What is the superficial fascia of the abdominal wall also known as?

Subcutaneous tissue.

How does the superficial fascia differ below the umbilicus?

It forms two layers: a superficial fatty layer and a deeper membranous layer.

What does the superficial fatty layer of superfical fascia contain?

Fat and varies in thickness.

What is the name of the superficial fatty layer in the abdominal wall?

Camper’s fascia.

What forms a specialized fascial layer over the penis in males?

Dartos fascia.

What is the deeper membranous layer of superficial fascia called?

Scarpa’s fascia.

What is the function of the five anterolateral abdominal wall muscles?

They maintain normal physiological functions and help keep abdominal viscera within the abdominal cavity.

List the three flat muscles of the abdominal wall.

External oblique, internal oblique, transversus abdominis.

What are the two vertical muscles of the abdominal wall?

Rectus abdominis and pyramidalis.

What is the rectus sheath?

An aponeurotic tendinous sheath enclosing the rectus abdominis and pyramidalis muscles.

What does the lower border of the external oblique aponeurosis form?

Inguinal ligament.

What is the function of the external oblique muscle?

Compresses abdominal contents and aids in trunk flexion.

What arteries supply the anterolateral abdominal wall?

Musculophrenic artery, inferior epigastric artery, superficial epigastric artery.

What is the anatomical significance of the linea alba?

It is formed by the entwining of the aponeuroses of the abdominal muscles at the midline.

What is the significance of the transversalis fascia?

It lines the abdominal cavity and is a continuous layer covering abdominal and pelvic cavities.

What does the external oblique muscle originate from?

Muscular slips from the outer surfaces of the lower eight ribs.

Where do the lower intercostal nerves supply sensation?

They supply the skin around the abdominal wall's anterior portion.

How do the lower intercostal nerves (T7 to T12) reach the muscles of the abdominal wall?

They pass deep to the costal cartilages and enter the anterolateral abdominal wall.

What type of connective tissue lies deep to the transversalis fascia?

Extraperitoneal fascia.

What supplies the innervation to the anterolateral abdominal wall?

T7 to T12 spinal nerves and L1 spinal nerve (iliohypogastric and ilio-inguinal nerves).

What happens at the arcuate line?

The aponeuroses of the abdominal muscles move anterior to the lower part of the rectus abdominis.

What is the function of the pyramidalis muscle?

Tenses the linea alba.

What are two examples of specialized structures formed by layers of fascia in the abdominal wall?

Dartos fascia and fundiform ligament of the penis.

What is the difference between preperitoneal and retroperitoneal fat?

Preperitoneal fat is on the anterior side, while retroperitoneal fat is on the posterior side of the abdominal cavity.

What is the role of the rectus abdominis muscle?

Flexes the vertebral column and compresses abdominal contents.

Where does lymphatic drainage from above the umbilicus go?

To axillary nodes.

Where does lymphatic drainage from below the umbilicus go?

To superficial inguinal nodes.

What arteries are responsible for venous drainage in the abdominal wall?

Veins follow the arteries and are named similarly.

What distinguishes the deeper layer of fascias covering the abdominal muscles?

The transversalis fascia is more developed than other layers.

What layer of fascia continues into the pelvic cavity?

Parietal pelvic (endo-pelvic) fascia.

What does the term 'rectus sheath' specifically refer to?

The aponeurotic sheath that encloses the rectus abdominis muscle.

Where does the rectus abdominis muscle widen and thin?

As it ascends from the pubic symphysis to the costal margin.

What is the role of the internal oblique muscle?

Compresses abdominal contents and helps flex and rotate the trunk.

What is the innervation of the rectus abdominis muscle?

Anterior rami of lower seven thoracic spinal nerves (T7 to T12).

What arteries supply the inferior part of the abdominal wall?

Inferior epigastric artery and deep circumflex iliac artery.

What is the composition of the rectus sheath at different points?

Anterior wall: external oblique and half internal oblique aponeurosis; posterior wall: other half of internal oblique and transversus abdominis aponeurosis.

What happens to superficial fascia transitions in males?

It continues over the penis to form the superficial fascia of the penis.

What creates the inguinal canal?

The trough formed by the inguinal ligament.

What structural support do abdominal muscles provide during forced expiration?

They push the viscera upward, assisting the diaphragm.

What forms the tendinous intersections visible in individuals with a developed rectus abdominis?

Fibrous bands intersecting the rectus abdominis.

What is a characteristic of Scarpa’s fascia?

It is thin, membranous, and contains little or no fat.

What does the external oblique aponeurosis thicken to form?

The inguinal ligament.

What is 'Camper's fascia'?

The superficial fatty layer of the abdominal wall's superficial fascia.

What kind of structure is the visceral peritoneum?

The peritoneum covering the abdominal viscera.

What is the relationship between the external oblique and the internal oblique muscles?

The internal oblique is deep to the external oblique.

How is the inguinal ligament connected to the pelvic bones?

It passes between the anterior superior iliac spine and the pubic tubercle.

What surrounds the abdominal cavity?

A continuous layer of deep fascia known as the transversalis fascia.

What varies in thickness and is continuous over the inguinal ligament?

The superficial fatty layer of the superficial fascia.

What are the functions of the abdominal wall musculature during micturition and defecation?

Increase intra-abdominal pressure.

What helps maintain the position of abdominal viscera?

Contraction of the anterolateral abdominal wall muscles.