Reproduction 4 - Pelvis and Perineum 2 Flashcards
1
Q
What are the 2 triangles the perineum can be divided into?
A
Urogenital triangle
Anal triangle
2
Q
What is A?
A
Pubic symphysis
3
Q
What is B?
A
Ischial tuberosity
4
Q
What is C?
A
Coccyx
5
Q
What is D?
A
Urogenital triangle
6
Q
What is E?
A
Anal triangle
7
Q
Which bony prominences separate each of the triangles?
A
Ischial tuberosities
8
Q
A thin sheet of deep fascia stretches between right and left sides of the pubic arch, below the pubic symphysis.
What is the name given to this fascia?
A
Perineal membrane
9
Q
What is support to the organs of the perineum provided by?
A
Support to the organs of the perineum is provided by the muscles of the perineum and fascial planes – there are some anatomical variations between the male and female perineal muscles
10
Q
List the muscles and fascia of the perineum?
A
- External anal sphincter
- Superficial transverse perineal
- Deep transverse perineal
- External urethral sphincter
- Bulbospongiosus
- Ischiocavernosus
11
Q
For external anal sphincter:
- main actions
- innervation
A
- Main actions
- Constricts anal cavity during peristalsis, resisting defication, supports and fixes perineal body
- Innervation
- Branches of pudendal nerve (S2-S4)
12
Q
For superficial transverse perineal muscle:
- main actions
- innervation
A
- Main actions
- Support and fix perineal body (pelvic floor) to support abdominal pelvic viscera and resist increased intra-abdominal pressure
- Innervation
- Branches of pudendal nerve (S2-S4)
13
Q
For deep transverse perineal:
- main actions
- innervation
A
- Main actions
- Support and fix perineal body (pelvic floor) to support abdomninal pelvic viscera
- Resist increased intra-abdoinal pressure
- Compress urethra to maintain urinary continence
- Innervation
- Branches of pudendal nerve (S2-S4)
14
Q
For external urethral sphincter:
- main actions
- innervation
A
- Main actions
- Compress urethra to maintain urinary incontinence
- Innervation
- Branches of pudendal nerve (S2-S4)
15
Q
For bulospingiosus (male):
- main actions
- innervation
A
- Main actions
- Compresses bulb of penis to expel last drops of urine/semen
- Assist erection by compressing outflow via deep perineal vein and by pushing blood from bulk into body of penis
- Innervation
- Branches of pudendal nerve (S2-S4)
16
Q
For bulbosponiosus (female):
- main actions
- innervation
A
- Main actions
- “Sphincter” of vagina assists in erection of clitoris
- Compressed greater vestibular gland
- Innervation
- Branches of pudendal nerve (S2-S4)
17
Q
For ischiocavernosus (male):
- main actions
- innervation
A
- Main actions
- Maintains erection of penis by compressing outflow veins and pushing blood from root of penis into body
- Innervation
- Branches of pudendal nerve (S2-S4)
18
Q
For ischiocavernosus (female):
- main actions
- innervation
A
- Main actions
- Maintains erection of clitoris by compressing outflow veins and pushing blood from root of clitoris into body
- Innervation
- Branches of pudendal nerve (S2-S4)
19
Q
Branches of what nerve supplies all muscles of the perineum?
A
Branches of pudendal nerve (S2-S4)
20
Q
What are the potential consequences if the perineal body is damaged/ruptured during childbirth?
A
Significant bleeding, long term pain or dysfunction
21
Q
What are the 2 layers of fascia important as additional support for the pelvic organs within the perineum?
A
These are the levatores ani and coccygei muscles and parietal fascia, making up the pelvic diaphragm.
22
Q
What makes up the pelvic diaphragm?
A
Levator ani and coccygei muscles
and parietal fascia
23
Q
What structures pierce through the pelvic diaphragm?
A
Urethra
Vagina
Anal canal
24
Q
Is the urethra longer in males or females?
A
The urethra is longer in males compared to females due the number of structures it has to traverse
25
What is A?
Rectum
26
What is B?
Prostatic urethra
27
What is C?
Membranous urethra
28
What is D?
Deep perineal space
29
What is E?
Bulb of penis
30
What is G?
External urethral orifice
31
What is H?
Spongy urethra
32
What is I?
Prostate
33
What is J?
Pubic symphysis
34
What is K?
Urinary bladder
35
What are the 3 parts of male urethra?
1. Prostatic urethra
2. Membranous urethra
3. Spongy urethra
36
What is the narrowest part of male urethra?
Membranous urethra?
37
What is the widest part of male urethra?
Prostatic urethra
38
The urethra in males is at risk of becoming narrowed due to what?
Enlargement of prostate
39
What does the male external genitalia comprise of?
Testes, scrotum and penis
40
What are the different parts of the penis?
* Left and right corpus cavernosa
* Single corupus spongiosum
* Glans penis (terminal part)
* Prepuce (foreskin)
41
The penis provides transit for urethra via what?
Urethral meatus
42
The corpus cavernosa is covered by a fascial layer called?
Buck's fascia
43
Through what part of the penis is the urethra transmitted through?
Corpus spongiosum
44
The majority of the erectile tissue in the penis is in what part?
Corpus cavernosa
45
Sensory innervation of the penis is through what?
Dorsal nerve of penis - a branch of pudendal nerve
46
What is the dorsal nerve of the penis a branch of?
Pudendal nerve
47
Where is the internal/vesical urethral sphincter located in females?
Located inferiorly at the neck of the bladder
48
Is the internal/vesical urethral sphincter in females voluntary or involuntary?
* Involuntary
* Sympathetic fibres from T10-L2 through inferior hypogastric plexus then vesicle nervous plexus
49
What nerves innervate the internal/vesical urethral sphincter in females?
* Sympathetic fibres from T10-L2 through inferior hypogastric plexus then vesicle nervous plexus
50
Where is the external urethral sphincter found in females?
distal and inferior to the internal urethral sphincter in the deep pernieal pouch
51
Where is the external urethral sphincter found in males?
Deep perineal pouch, inferior to the prostate at level of the membranous urethra in males
52
Is the external urethral sphincter voluntary or involuntary?
* Voluntary
* Somatic nervous system, S2-S4
53
What nerves supplies the external urethral sphincter?
Somatic nervous system, S2-S4
54
What can urinary incontinence develop due to in both males and females?
Disruption of internal and/or external urethra sphincters
55
What are the biggest risk factors for males and females for urinary incontinence?
* Males
* Any form of prostatic surgery to overcome urinary retention
* Females
* Childbirth can weaken the ligaments supporting the pelvic floor
56
What is the vulva?
The vulva is the collective name for the female external genitalia.
57
What are the 6 contents of the vulva?
1. Mons pubis
2. Labia majora
3. Labia minora
4. Clitoris
5. Vestibule
6. Bartholin' glands (vestibular glands)
58
What nerve and artery supplies the structures of the vulva?
* Nerve
* Pudendal nerve
* Artery
* Internal pudendal artery
59
What is the vestibule?
The vestibule is the area enclosed by the labia minora and contains the terminal aspects of the vaginal orifice and urethra
60
The vestibule contains the inferior aspects of what?
Urethra, vagina and ducts of the greater and lesser vestibule glands
61
What is the clitoris?
Mirroring the corpus cavernosa in the male, the [clitoris](https://www.anatomy.tv/anatomytv/html5ui_2018/#/product/har_pelvis_2014/type/Text%20articles/id/42818/layer/5/angle/35/structureID/-1) is the erectile tissue found within the female external genitalia.
62
What is the clitoris composed of?
It is comprised of 2 crura, which meet in the midline to form the body. This then projects downwards to the prepuce and glans which lies in the anterior labial commissure.
63
What is the equivalent of the corpus cavernosa in females?
Clitoris
64
What is the equivalent of the corpus spongiosum in females?
There is none
65
The anal triange is the area between what?
The anal triangle is the area between the ischial spines and coccyx
66
What does the anal triangle contain?
It contains the terminal part of the gastro-intestinal tract, the anus.
67
How long is the anus?
Approx 4cm
68
What are the 2 sphincters controlling defication and are they voluntary or involuntary?
* Internal sphincter
* Involuntary
* External sphincter
* Voluntary
69
Somatic sensation in the anus extends upwards from where to where?
Somatic sensation extends upwards from the external environment to the inter-sphincteric groove (the ‘white line’)
70
What is found lateral to the anal canal and inferior to the pelvic floor?
2 fat containing fossa called the [ischio-anal (ischio-rectal) fossa](https://www.anatomy.tv/anatomytv/html5ui_2018/#/product/har_pelvis_2014/type/MRI%20Views/id/42865/layer/0/angle/4/structureID/1336332)
71
What does the ischio-anal (ischio-rectal) fossa allow?
These allow the anal canal to expand during defaecation.
72
What is A?
Obturator internus meatus
73
What is B?
Levator ani muscle
74
What is C?
external anal sphincter
75
What is D?
Anal canal
76
What is E?
Ischiorectal fossae
77
What is F?
pudendal canal containing pudendal artery and vein
78
What is G?
Pudendal nerve
79
What is H?
Rectum
80
What allows a neurovascular bundle to enter the ischio-anal(rectal) fossae?
Lesser sciatic foramen
81
What structres are in the neurovascular bundle entering the ischio-anal (rectal) fossae?
Internal pudendal artery and vein, pudendal nerve, obturator internus tendon and nerve to obturator internus
82
What structures does the neurovascular bundle entering the ischio-anal (rectal) fossae supply?
* External anal sphincter
* Peri-anal skin
* Superficial pouch
* Deep pouch
83
WHat can extent laterally into the ischio-anal fossa to form abscessed?
Anal crypts can extend laterally into the ischio-anal fossa forming abscesses within this relatively ischaemic area. These can spread rapidly with these peri-anal abscesses requiring drainage under general anaesthesia.
