Abdominal surface of the diaphragm
Completing this study unit will allow you to:
- Describe the structures and functions of the diaphragm.
- Name the openings of the diaphragm and list the structures which travel through them.
- Identify the nerves and vessels travelling along the abdominal surface of the diaphragm and name the neurovascular supply of the diaphragm.
The diaphragm is the largest and most important muscle for respiration and forms the roof of the abdominal cavity. It is a musculotendinous structure composed of skeletal muscle and a centrally located aponeurosis, known as the central tendon of the diaphragm. Several openings, also called apertures, allow for the passage of structures across the diaphragm: the aortic hiatus, esophageal hiatus and caval foramen.
Two main arteries branch off the abdominal aorta and travel along the abdominal surface of the diaphragm, providing its arterial blood supply: the left and right inferior phrenic arteries. Another branch arising from the abdominal aorta is the celiac trunk, which in turn gives rise to three arteries that travel directly beneath the abdominal surface of the diaphragm: the common hepatic, left gastric and splenic arteries.
The diaphragm is closely related to components of the axial skeleton, including the ribs, sternum and lumbar vertebrae, as well as several muscles, such as the psoas major and quadratus lumborum muscles.
Watch the following video to discover more about the structures associated with the abdominal surface of the diaphragm.
Take a quiz
Now it’s time for you to make all of that new information stick by trying out the quiz below.
Are you looking for a further challenge? Why not try the following quiz, which you can customize yourself, to include various structures found on and around the diaphragm.
Take a closer look at each of the structures on the abdominal surface diaphragm in the gallery below.
|Parts||Skeletal muscle (sternal, costal and lumbar parts), central tendon|
|Function||Main muscle responsible for respiration; increases abdominal pressure to expel feces, vomit and urine; applies pressure on the esophagus to prevent acid reflux|
Aortic hiatus: Aorta, azygos vein, thoracic duct
Esophageal hiatus: Esophagus, branches of the left gastric artery and vein, anterior and posterior vagal trunks
Caval foramen: Inferior vena cava, branches of the right phrenic nerve
|Blood supply||Left and right phrenic arteries (branches of the abdominal aorta)|
|Innervation||Left and right phrenic nerves (C3-C5)|
|Musculotendinous structures||Right and left crus of the diaphragm; median, medial and lateral arcuate ligaments|