Lecture 20 - The Pelvis and Pelvic Viscera Flashcards
(79 cards)
1
Q
What is the pelvis?
A
- Bowl shaped
- Bounded by hip bones, sacrum, and coccyx
- Divided into two regions
2
Q
What are the two pelvic openings?
A
- Pelvic inlet/brim
- Pelvic outlet
3
Q
What are the 2 regions of the pelvis?
A
- False (greater)
- True (lesser)
4
Q
What is the false pelvis?
A
- Superior to the pelvic brim
- Contains abdominal viscera
5
Q
What abdominal viscera are located in the false pelvis?
A
- Cecum/appendix
- Sigmoid colon
- Loops of jejunum/ileum
6
Q
What is the true pelvis?
A
- Inferior to the pelvic brim
- Between pelvic inlet and outlet
- Funnel shaped
- Contains pelvic viscera
7
Q
Which pelvic viscera are located in the true pelvis?
A
- Rectum/anal canal
- Bladder
- Sex-specific viscera
8
Q
What is the true pelvis a framework for?
A
The pelvic cavity and perineum
9
Q
What are the two types of pelvic shapes?
A
- Gynaecoid
- Android
10
Q
What characterizes a gynaecoid pelvis?
A
- Wide and shallow
- Wide oval-shaped inlet
- Larger round outlet
- Subpubic angle (~90-100 degree)
11
Q
What characterizes an android pelvis?
A
- Narrow and deep
- Heart-shaped inlet
- Narrow, oblong outlet
- Subpubic angle (~70 degrees)
12
Q
What are the 3 parts of the hip bones?
A
- Ilium
- ischium
- Pubis
13
Q
What are the structures on the wing of the ilium?
A
- Iliac crest
- Iliac fossa
- Anterior superior iliac spine (ASIS)
- Sacral articular surface
14
Q
What are the structures on the body of the ilium?
A
- Anterior inferior iliac spine (AIIS)
- Greater sciatic notch
15
Q
What are the structures on the ischium?
A
- Ischial spine
- Lesser sciatic notch
- Ischial tubersosity
- Ischial ramus
16
Q
What are the structures on the pubis?
A
- Superior pubic ramus
- Pubic tubercle
- Inferior pubic ramus
17
Q
What bones of the hip form the obturator foramen?
A
Ischium and pubis
18
Q
What is the acetabulum?
A
Hip joint socket
19
Q
What are the number of vertebrae of the sacrum?
A
5 vertebrae (S1-S5)
20
Q
What are the number of vertebrae of the coccyx?
A
3-5 vertebrae
21
Q
What are the structures on the anterior side of the sacrum?
A
- Base
- Sacral promontory
- Ala (wing)
- Anterior sacral foramina
22
Q
What are the structures on the posterior side of the sacrum?
A
- Sacral canal
- Posterior sacral foramina
- Sacral hiatus
23
Q
What are the crests on the posterior sacrum?
A
- Lateral sacral crest
- Median sacral crest
24
Q
What is the articular surface on the posterior sacrum?
A
Articulation with the ilium at the sacroiliac joint
25
What is the tip of the coccyx called?
The apex
26
What is the superior border of the pelvic inlet?
Sacral promontory (S1)
27
What is the superior-medial border of the pelvic inlet?
Anterior edge of the sacral ala (sacrum)
28
What is the lateral border of the pelvic inlet?
Arcuate line (ilium)
29
What is the inferior-medial border of the pelvic inlet?
Pectineal line (pubis)
30
What is the inferior border of the pelvic inlet?
Superior edge of the symphysis pubis
31
What structures are in the same vertical plane?
ASIS and pubic tubercles
32
What structures are in the same horizontal plane?
Coccyx and upper margin of the pubic symphysis
33
What is the angle of the pelvic inlet?
50-60 degrees (relative to horizontal plane)
34
What are the ligaments of the pelvis?
1. Sacrospinous ligament (SSL)
2. Sacrotuberous ligament (STL)
3. Inguinal ligament
35
Where does the sacrospinous ligament run?
Sacrum to ischial spine
36
What foramina is formed by the sacrospinous ligament?
The greater sciatic foramina
37
Where does the sacrotuberous ligament run?
Sacrum to ischial tuberosity
38
What foramina is formed by the sacrotuberous ligament?
The lesser sciatic foramina
39
What is the function of the SSL and the STL?
1. Prevent upward tilting of the distal sacrum
2. Pull pelvis down
40
What are the pelvic wall muscles?
1. Piriformis
2. Obturator internus
3. Pelvic diaphragm
41
What muscles makes up the pelvic diaphragm?
1. Coccygeus
2. Levator ani
42
What is the function of the pelvic wall muscles?
- Turn the pelvis into a "bowl"
- Contain viscera
- Seals off the lateral walls and floor
43
What does the levator avi create?
The pelvic floor
44
What are the muscles that make up the pelvic floor?
1. Puborectalis
2. Pubococcygeus
3. Iliococcygeus
45
Where does the puborectalis run?
- Slings around rectum
- From L to R superior pubic rami and OI fascia
46
Where does the pubococcygeus run?
- Superior pubic rami and OI fascia to coccyx
- L/R meet at median fibrous ridge
47
Where does the iliococcygeus run?
Ischium/OI fascia to coccyx and fibrous ridge (L/R)
48
What are the functions of the levator ani and coccygeus muscles?
1. Support abdominopelvic viscera
2. Control urinary/fecal continence
3. Increase intra-abdominal pressure
49
What are the two hiatuses created by the left and right levator ani?
1. Rectus hiatus
2. Urogenital hiatus
50
What is the rectal hiatus for?
Rectum/anal canal
51
What is the urogenital hiatus for?
Urethra and vagina
52
What type of organ is the upper 1/3 of the rectum?
Intraperitoneal
53
What type of organ is the middle 1/3 of the rectum?
Retroperitoneal
54
What type of organ is the lower 1/3 of the rectum?
Sub-peritoneal
55
What are the sections of the rectum?
1. Rectum
2. Rectal ampulla
56
What structures is present in the rectum?
Transverse folds
57
What separates the rectum and the anal canal?
Anorectal junction
58
What are the structures present in the anal canal?
1. Anal columns
2. Sinuses
3. Valves
59
What do the sinuses do?
Secrete mucus
60
What do the valves do?
Mark the transition from mucosa to skin
61
What are the muscles that play a role on the anal canal?
1. Puborectalis
2. External anal sphincter (voluntary)
3. Internal anal sphincter (involuntary)
62
What pulls the anorectal junction forward?
Tonic/constant contraction of the puborectalis
63
What does the forward pull on the anorectal junction ensure?
Fecal continence
64
How is fecal continence ensured?
- Creating a ~90 degree angle at the anorectal junction
- Seals off the anal canal
65
What does relaxation of the puborectalis lead to?
- Increase intra-abdominal pressure
- Straightening of the anorectal junction (120-140 degrees)
- Relaxation of internal and external anal sphincters
- Voiding
66
Where is the urinary bladder located?
Lies anterior to the rectum, sub-peritoneally
67
Where is the urinary bladder located when empty?
Fully within the pelvic cavity (true pelvis)
68
Where is the urinary bladder located when full?
Expands into the abdominal cavity (false pelvis)
69
What is the shape of the urinary bladder?
- 3-sided pyramid
- Tipped over with apex pointed to the pubic symphysis
70
What are the structures of the urinary bladder?
1. Body (anterior)
2. Base (posterior)
3. Fundus
4. Apex
5. Median umbilical ligament
6. Ureters
7. Urethra
71
What is the median umbilical ligament a remnant of?
Urachus: Fetal connection to umbilicus for urine removal
72
For an assigned female at birth, what structures are present for the urinary bladder?
1. Ureteric orifices
2. Interuteric ridge
3. Trigone
4. Internal urethral orifice
5. Urethra
6. External urethral orifice
73
What are the sphincters of the urinary bladder for an AFAB?
1. Internal urethral sphincter (involuntary)
2. External urethral sphincter (voluntary)
74
What muscle lines the urinary bladder?
Detrusor muscle
75
Where is the uterus located in an AFAB?
Between the bladder and rectum
76
What structures are found in an assigned male at birth?
1. Seminal vesicles
2. Prostate glands
77
What is the difference between an AFAB and an AMAB urethra?
Urethra longer in AMAB
78
Where does the abdominal portion of the ureter pass?
Posterior to the gonadal vessels (at iliac crest)
79
Where does the ureter enter the pelvis?
By crossing anterior to the bifurcation of the common iliac artery
