GS: Diaphragm

Question 1

What is the diaphragm?

Answer 1

sheet of muscle and tendon that separates the thorax from the abdomen

Question 2

What is the main function of the diaphragm?

Answer 2

respiration

Question 3

What does the diaphragm act as the most superior border of?

Answer 3

abdomen

Question 4

Where does the diaphragm develop?

Answer 4

in the neck mainly from septum transversym close to the thoracic inlet

Question 5

What is the nerve supply of the diaphragm?

Answer 5

anterior rami of C3, C4, C5 (phrenic nerve)

Question 6

What are the other embrological components of the diaphragm?

Answer 6

• pleuroperitoneal membranes
• dorsal mesentery of the oesophagus
• ingrowth from the body wall

Question 7

Answer 7

Question 8

Answer 8

Question 9

What are the 4 sources of origin of the diaphragm?

Answer 9

• spetum transversum
• 2 pleuro-perioneal folds or membranes that fuse with septum transversum and close the pericardio-peritoneal canals
• Oesophagus and its mesentery in the midline dorsally
• ingrowth from the body wall

Question 10

Describe the structure of the diaphragm

Answer 10

originate from the xiphoid process, then the costal margin, ribs 11 and 12, then posteriorly and medial arcuate ligaments (thickenings of thoracolumbar and psoas fascia respectively)

Question 11

Where do the fibres of the diaphragm converge?

Answer 11

central tendon

Question 12

What does the diaphragm have posteriorly?

Answer 12

strong, muscular left and right crura

Left = L1 and L2

Right = L1, L2 and L3

Question 13

Where does the median arcuate ligament lie?

Answer 13

midline, netween the left and right crus at the level of T12

Question 14

What do the fibres of the right crus do?

Answer 14

cross over the midline to the left to form a loop or a sling around the oesophagus

Question 15

What is the inferior surface of the diaphragm lined by?

Answer 15

peritoneum apart from the ‘bare area’ which is posterior to part of the liver

Question 16

How does the peritoneal of the liver interact with the diaphragm?

Answer 16

O n the superior surface ofthe liver the peritoneum reflects on to the diaphragm to create narrow subphrenic intraperitoneal (potential) spaces where fluids can collect from the abdomen.

Question 17

Describe the opening at T8

Answer 17

At the level of T8 (through the central tendon)

• Pasing down into the abdomen – Right phrenic nerve
• Passing up out of the abdomen– Inferior vena cava

Question 18

Describe the opening at T10

Answer 18

At the levek of T10 (through the right crus, but left of the midline)

• Passing out of the abdomen - left gastric artery from the coeliac artery
• Passing into the abdomen - oesophgaus, anterior and posterior vagal trunks, left gastric vein

Question 19

Describe the opening at T12

Answer 19

At the level of T12 (through the median arcuate ligament)

• passing out of the adbomen - thoracic duct, azygos and hemi azygos veins
• Passing into the abdomen - descending thoracic aorta

Question 20

Describe the condition hiatus hernia

Answer 20

small aprt of the stomach herniates through the diaphragm into the thorax

Question 21

What are the two types of hiatus hernia?

Answer 21

sliding and rolling

Question 22

What occurs in a sliding hiatus hernia?

Answer 22

intra-abdominal part of the GO junction has managed to get above the diaphragmatic oesophgeal hiatus formed by the left and right crura, but mainly the right crus

Question 23

What are the main symptoms experienced due to hiatus hernai?

Answer 23

severe heartburn and dysphagia

may be made worse after eating food or lying down

Question 24

Why is the pain of sliding hiatus hernia worse after eating food?

Answer 24

• Normally all the acid secreting parts of the stomach are below the oesophgeal opening
• Cardia is above constrictions allowing acid to be secreted into the lower oesophagus
• Food and fluid in stomach = gastric acid release
• Irritates the lower oesophagus; increase in pain and discomfort

Question 25

What occurs in a rolling hiatus hernia?

Answer 25

part of the fundus of the stomach has herniated through the diaphragm but the gastro-oesophageal junction is still intact below the diaphragm

Question 26

How does a rolling hiatus hernia usually present?

Answer 26

dysphagis from compression of the oesophgeus, or early satiety, and in some cases inability to hold solid foods at all

Question 27

What is a congenital diaphragmatic heria?

Answer 27

found in newborn babies due to incomplete development of the diaphragm

A large amount of midgut can structures can pass into the thorax. (most commonly the left side)

Question 28

What is the impact of a diaphramatic hernia?

Answer 28

impair lung function and sometimes development

babies present with cyanosis and respiratory distress soon after birth

Question 29

Where is irritation of the diaphragm referred to?

Answer 29

C4; shoulder tip

Brain cannot localise visceral pain