GI Anatomy 6 - Week 4 Flashcards

1
Q

The control of the excretion of faeces requires…

A

Holding area (rectum)
Normal visceral afferent nerve fibres
Functioning muscle sphincters
Normal cerebral function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which kind of pathology can cause incontinence?

A

Neurological - e.g. dementia, stroke, MS, trauma e.g. spinal cord injury or during childbirth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

In addition to neurological pathology, which other factors influence faecal continence?

A

Medications, age-related degeneration of nerve innervation of muscle, consistency of stool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The pelvic cavity lies within…

A

the bony pelvis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The pelvic cavity lies between…

A

The pelvic inlet and pelvic floor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which part of the GI tract passes through the pelvic floor?

A

Rectum/anal canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the pelvic floor muscle called?

A

Levator ani

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

At which spinal level is the “Recto-sigmoid junction”?

A

S3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which structural change occurs at the recto-sigmoid junction?

A

Loss of tenaie coli/ haustra

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

At what point does the rectum become the anus?

A

tip of the coccyx just prior to passing through the levator ani muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

In which cavity is the rectum in?

A

Pelvis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In which cavity is the anal canal & anus?

A

Perineum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where does the rectal ampulla lie?

A

immediately superior to the levator ani muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the purpose of the rectal ampulla?

A

walls can relax to accommodate faecal material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which structure covers the superior rectum?

A

Peritoneum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Anterior to the rectum, in females fluid may accumulate in…

A

Rectouterine pouch (of Douglas)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Anterior to the rectum, in males fluid may accumulate in…

A

Rectovesical pouch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

In the male, which structure lies anterior to the rectum?

A

(Bladder) and prostate gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

In the female, which structures lie anterior to the rectum?

A

Vagina & cervix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which bones make up the hip?

A

Isheum, ileum & pubic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which 2 muscles make up the pelvic floor?

A

Levator Ani & Coccygeus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which 3 fibres make up the levator ani?

A

Puborectalis, Pubococcygeus and Iliococcygeus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Which type of muscle is the levator ani?

A

Skeletal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The levator ani muscle reflexively contracts during…

A

Increased intra-abdominal pressure eg. coughing, sneezing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The levator ani muscle must relax for…

A

Defecation and urination

26
Q

What is the nerve supply to the levator ani muscle?

A

“nerve to levator ani”: (a branch of the sacral plexus) & pudendal (S2, 3, 4)

27
Q

Which part of the levator ani muscle is important for maintaining faecal continence?

A

Puborectalis

28
Q

What kind of sphincter is puborectalis?

A

Functional

29
Q

What kind of muscle is the internal anal sphincter?

A

Smooth

30
Q

What kind of muscle is the external anal sphincter?

A

Skeletal

31
Q

Explain how the anal sphincters are arranged.

A

Internal anal sphincter is a thickening of circular muscle, surrounded by the external anal sphincter which is composed of 3 layers of muscle.

32
Q

Where is the internal anal sphincter found?

A

Superior 2/3 of anal canal

33
Q

Where is the external anal sphincter found?

A

Inferior 2/3 of anal canal

34
Q

Contraction of the internal anal sphincter is stimulated by…

A

Sympathetic nerves

35
Q

Contraction of the internal anal sphincter is inhibited by…

A

Parasympathetic nerves

36
Q

Contraction of the external anal sphincter is stimulated by…

A

Pudendal nerve (S2,3,4)

37
Q

What is the nerve supply in the perineum?

A

Somatic sensory/motor

38
Q

What are the two spinal cord levels for the rectum & anus?

A

T12-L2 and S2-S4

39
Q

What is the significance of T12-L2?

A

Sympathetic ganglia for the hindgut

40
Q

The pudendal nerve is a branch from which plexus?

A

Sacral

41
Q

What spinal cord level does the pudendal nerve arise?

A

S2,3,4

42
Q

Where does the pudendal nerve exit the pelvis?

A

Greater sciatic foramen

43
Q

Where does the pudendal nerve enter the perineum?

A

Lesser sciatic foramen

44
Q

Which structures does the pudendal nerve supply?

A

Those of the perineum

45
Q

How may faecal incontinence arise during childbirth?

A

Branches of pudendal nerve may be stretched, puborectalis or external anal sphincter could be torn

46
Q

What is meant by the pectinate line?

A

Embryological boundary -

Arterial supply, venous drainage, lymphatic drainage and nerve supply differ above and below pectinate line

47
Q

What is the nerve supply above the pectinate line?

A

Autonomic

48
Q

What is the nerve supply below the pectinate line?

A

Somatic (pudendal nerve)

49
Q

What is the lymphatic drainage above the pectinate line?

A

Inferior mesenteric nodes

50
Q

What is the lymphatic drainage below the pectinate line?

A

Superficial inguinal nodes

51
Q

Explain lymphatic drainage of the pelvic organs.

A

Internal & external iliac nodes –> Common iliac –> Lumbar. All converge to thoracic duct.

52
Q

Explain venous drainage from the rectum/anal canal.

A

Above the pectinate line, the superior rectal vein drains to the IMV. Below the pectinate line, the middle and inferior rectal veins drain into the internal iliac vein.

53
Q

What is the difference between rectal varices and haemorrhoids?

A

Rectal varices form in relation to portal hypertension, Haemorrhoids are prolapses of the rectal venous plexuses

54
Q

Why do varices arise?

A

Dilation of collateral veins between portal and systemic venous systems

55
Q

Why do haemorrhoids form?

A

prolapses of the rectal venous plexuses due to raised pressure e.g. chronic constipation, straining, pregnancy

56
Q

Where are the ischioanal fossae located?

A

Ischioanal fossae (right and left) lie on each side of the anal canal

57
Q

What are the ischioanal fossae usually filled with?

A

Fat and CT

58
Q

An infection in the ischioanal fossae is called a….

A

Ischioanal abscess

59
Q

What is meant by proctoscopy?

A

viewing the interior of the rectum

60
Q

What is meant by sigmoidoscopy?

A

viewing the interior of the sigmoid colon

61
Q

What is meant by colonoscopy?

A

viewing the interior of the colon