Areas of the Abdomen Flashcards
Where is the inguinal triangle (Hesselbach’s triangle)?
Located within the inferomedial aspect of the abdominal wall
What is the inguinal triangle (Hesselbach’s triangle) alternatively known as?
The medial inguinal fossa
What are the borders of the inguinal triangle?
Medial – lateral border of the rectus abdominis muscle. Lateral – inferior epigastric vessels. Inferior – inguinal ligament
What is the clinical relevance of the inguinal triangle?
However, the triangle does demarcate an area of potential weakness in the abdominal wall – through which herniation of the abdominal contents can occur.
What is a hernia?
The protrusion of an organ or fascia through the wall of a cavity that normally contains it
What is the peritoneum?
Continuous membrane which lines the abdominal cavity (parietal) and covers the abdominal organs (visceral)
What is function of peritoneum?
It acts to support the viscera, and provides pathways for blood vessels and lymph to travel to and from the viscera.
What are the 2 layers of peritoneum?
- Parietal 2. Visceral Both types are made up of simple squamous epithelial cells called mesothelium
What does the parietal peritoneum line?
the internal surface of the abdominopelvic wall
What is the parietal peritoneum derived from?
Somatic mesoderm in the embryo
What nerve supply does the parietal peritoneum receive?
The same somatic nerve supply as the region of the abdominal wall that it lines; therefore, pain from the parietal peritoneum is well localised.
What does the visceral peritoneum line?
The visceral peritoneum invaginates to cover the majority of the abdominal viscera
What is the visceral peritoneum derived from?
Splanchnic mesoderm in the embryo
What nerve supply does the visceral peritoneum have?
The same autonomic nerve supply as the viscera it covers Unlike the parietal peritoneum, pain from the visceral peritoneum is poorly localised and the visceral peritoneum is only sensitive to stretch and chemical irritation.
Where is pain from the visceral peritoneum referred to?
Areas of the skin (dermatomes) which are supplied by the same sensory ganglia and spinal cord segments as the nerve fibres innervating the viscera
What is the peritoneal cavity?
A potential space between the parietal and visceral peritoneum. It normally contains only a small amount of lubricating fluid.
In order to adequately fulfil its functions, the peritoneum develops into a highly folded, complex structure. What is a mesentery?
Double layer of visceral peritoneum
What is function of mesentery?
It connects an intraperitoneal organ to (usually) the posterior abdominal wall. It provides a pathway for nerves, blood vessels and lymphatics to travel from the body wall to the viscera.
How is the mesentery named?
The mesentery of the small intestine is simply called ‘the mesentery’. Mesentery related to other parts of the gastrointestinal system is named according to the viscera it connects to, for example the transverse and sigmoid mesocolons, the mesoappendix.
What is the inguinal region?
The inguinal region is an area of the abdominal wall that extends from the ASIS to the pubic tubercle.
What is the inguinal canal?
The inguinal canal is a short passage that extends inferiorly and medially through the inferior part of the abdominal wall
What is purpose of inguinal canal?
Serves as a pathway by which structures can pass from the abdominal wall to the external genitalia
During development, where does the tissue that will become the gonads establish and then descend?
In the posterior wall and descend through the abdominal cavity
What is the gubernaculum?
A fibrous cord of tissue that attaches the inferior portion of the gonad to the future scrotum or labia and guides them during their descent