WEEK 9 PELVIS AND PERINEUM FINISHED

Question 1

What is the perineum?

Answer 1

Refers to an external surface area as well as a compartment of the body.
The region overlying the inferior pelvis outlet.
It is separate from the pelvic cavity by the pelvic diaphragm.
It is the saddle area, a diamond shaped area when the body is lying down and the legs are abducted

Question 2

What is the mons pubis?

Answer 2

A bit of fat which is found in front of the pubic symphysis. Protective role, more prominent in women. Helps to protect that area from pressure during intercourse

Question 3

Where is the mons pubis in relation to the perineum?

Answer 3

Anteriorly

Question 4

What is lateral to the perineum?

Answer 4

Legs

Question 5

What is posterior to the perineum?

Answer 5

Gluteal folds and intergluteal cleft

Question 6

What does mons mean?

Answer 6

Rounded eminence

Question 7

What is the boundaries of the perineum?
Anteriorly 
Posteriorly
Laterally 
Anterolaterally
Posterolaterally

Answer 7

Anteriorly -  pubis symphysis
Posteriorly - coccyx
Laterally - ischial tuberosities
Anterolaterally - inferior pubic rami
Posterolaterally - Sacrotuberous ligaments

Question 8

What is the perineal body

Answer 8

The midpoint line between the 2 ischial tuberosities.

A collection of tissue made up of both skeletal and smooth muscle and also different fibres collagen and elastin. Size and consistency varies and is just under the skin. It acts as an anchor and many structures attach to it.

Question 9

Where is the perineal body in males and female?

Answer 9

Posterior to the bulb of the penis, of the vestibule of the vagina.

Question 10

What does vestibule mean?

Answer 10

Opening

Question 11

What muscles attach to the perineal body?

Answer 11

Bulbospongiosum

External anal sphincter

Question 12

What is the perineal membrane?

Answer 12

A tough sheet of deep fascia that runs between the pubic arch and covers the anterior aspect of the pelvic outlet.

Question 13

What is the anal canal?

Answer 13

Terminal part of the bowel (2.3-3.5 cm long)
The anus is at the end of the anal canal.
Begins where the pubo recitals muscle forms a sling around the end of the rectum (anorectal junction)
Runs between the upper aspect of the pelvic diaphragm to the anus.

Question 14

What does anal mean?

Answer 14

Ring

Question 15

What direction does the anal canal run in?

Answer 15

Inferiorly and posteriorly.

Question 16

Where does the anal canal run in relation to the perineal body?

Answer 16

Between the perineal body and the anococcygeal ligament.

Question 17

What are the 2 triangles in the perineum?

Answer 17

Anterior triangle is the urogenital triangle

Posterior triangle is the anal triangle

Question 18

poos ft Joshuopathy

Answer 18

yep

Question 19

What is the external anal sphincter?

Answer 19

Large band of voluntary muscle.
Found either side of the inferior 2/3 of the anal canal
Blends superiorly with puborectalis.
Supplied by S4 inferior rectal nerve

Question 20

What is the internal anal sphincter?

Answer 20

Involuntary band of muscle that surrounds the superior 2/3 of the anal canal.
It is a thickening of the muscle within the bowel and is supplied by the PNS through the pelvic splanchnic nerves.
The muscle direction is both circular and longitudinal

Question 21

What are anal columns? What do they consist of? What do they contain? What happens at the inferior ends?

Answer 21

Longitudinal ridges in the superior half of the mucous membranes of the anal canal.
They consist of layers of mucous membrane
Contain the terminal branches of the superior rectal artery and vein.
In the inferior ends, the columns are joined by anal valves.

Question 22

What is superior to the anal valves?

Answer 22

Sinuses which when compressed release mucous which aids in defecation.

Question 23

What is the pectinate line? What does it mean in terms of embryonic development?

Answer 23

The irregular line produces by the anal valves.

Above the line is endoderm, below the line is ectoderm.

Question 24

What does the pectinate line divide the anus into? Why is it relevant?

Answer 24

Into superior and inferior regions, the different regions are derived from different embryonic tissue?

Question 25

What is the arterial supply of the anal canal superior to the pectinate line? what does it drain into?

Answer 25

The superior rectal artery. Drains into the portal venous system (goes through the liver to get to the IVC)

Question 26

What is the arterial supply of the anal canal inferior to the pectinate line? what does it drain into?

Answer 26

The inferior rectal artery. Drains to the Caval system straight into inferior vena cava.

Question 27

What is the innervation of the anal canal superior to the pectinate line?

Answer 27

Autonomic (inferior hypogastric plexus)

Question 28

What is the innervation of the anal canal inferior to the pectinate line?

Answer 28

Somatic (pudendal nerve S2-S4)