Anatomy of the Pelvic Region Flashcards
The pelvis is composed of 2 hip bones, left and right. Lebel the main features of the hip bone, using the labels below:
Ilium Hip bone Ischium Pubic symphysis Coccyx Sacrum
1 - Hip bone 2 - Sacrum 3 - Coccyx 4 - Ilium 5 - Pubic symphysis 6 - Ischium
What is the sacrum?
- bottom of the vertebral column
- consists of S1-S5 fused vertebrae that fuses with the coccyx
- shaped as a triangular bone
What is the sacro-iliac joint?
- joint between the sacrum and the ilium bones of the pelvis
- connected by strong ligaments.
Each hip bone has 3 key parts, what are they?
- illium
- ischium
- pubic bone
When sitting, which part of the hip bone is the main weight bearing site?
1 - ischium tuberosity
2 - sacrum
3 - acetabulum
4 - pubis
1 - ischium tuberosity
Each hip bones has 2 ramus which are curved parts of a bone that gives structural support to the rest of the bone. What are the 2 ramus located on each pelvic bone called?
1 - superior pubic ramus
2 - inferior pubic ramus
What is the ischial spine?
- posterior border of the body of the ischium bone of the pelvis
The sacro-iliac joint and the pubic symphysis bring together the 2 pelvic bones creating a complete bony ring. What is this bony ring called?
1 - pelvic ring
2 - hip cavus
3 - pelvic inlet/brim
4 - pelvic outlet
3 - pelvic inlet/brim
What is the true pelvis, also known as the lesser pelvis?
1 - region of pelvic inlet/brim
2 - region of pelvic ring
3 - region of hip cavus
4 - region of pelvic outlet
1 - region of pelvic inlet/brim
- the region below the pelvic inlet/brim (formed by the sacro-iliac joint and pubic symphysis)
What is the false pelvis, also known as the greater pelvis?
- located superiorly to true pelvis above the pelvic inlet/brim
What is the superior pelvic aperature more commonly known as?
1 - pelvic ring
2 - hip cavus
3 - pelvic inlet/brim
4 - pelvic outlet
3 - pelvic inlet/brim
What is the inferior pelvic aperture?
- defines the lower margin of the lesser (true) pelvis
- opening at bottom of pelvis
What organs are contained within the true pelvis (lesser pelvis) in males and females?
- males = rectum, bladder, prostate and part of the colon
- females = rectum, bladder, uterus/ovaries and part of the colon
Label the borders of the pelvic inlet/brim/true pelvis using the labels below:
sacral promontory (head of something, here it is head of sacrum) arcuate line of ilium sacral ala pubic symphysis pecten pubis linea terminalis
1 - sacral promontory (head of something, here it is head of sacrum) 2 - sacral ala 3 - arcuate line of ilium 4 - pecten pubis 5 - linea terminalis 6 - pubic symphysis
Label the borders of the pelvic outlet using the labels below:
tip of the coccyx
sacrotuberous ligament
ischial tuberosities laterally
pubic arch
1 - sacrotuberous ligament
2 - tip of the coccyx
3 - ischial tuberosities laterally
4 - pubic arch
Out of the 4 types of pelvis in the image below, named gynecoid, android, anthropoid and platypelloid pelvis, which is the one that most women have, and the one that allows for the easiest child birth?
- gynecoid pelvis
Out of the 4 types of pelvis in the image below, named gynecoid, android, anthropoid and platypelloid pelvis, which is the one that most men will have?
- android pelvis
What is the pubic arch?
- convergence of the inferior rami of the ischium and pubis on either side, below the pubic symphysis
- the angle at which they converge is known as the subpubic angle
Why is it important to investigating which type of pelvis a woman could have from the 4 types in the image below, named gynecoid, android, anthropoid and platypelloid pelvis?
- can identify if they are likely to have any problems in child birth
- can be identified on X-ray
What is the perineum?
1 - area around genital organs
2 - area between thighs between anus and genitals
3 - area around umbilicus
2 - area between thighs between anus and genitals
- most inferior part of pelvic outlet
The perineum is the area between the thighs between anus and genitals and the most inferior part of pelvic outlet. This can be divided into 2 regions, what are they?
1 - quadrangular and urogenital triangle
2 - rhomboid and anal triangle
3 - anal and urogenital triangle
4 - urogenital and quadrangular triangle
3 - anal and urogenital triangle
- anal triangle (posterior half or triangle)
- urogenital triangle (anterior half or triangle)
What is the term given to the muscles that fill the superior aspect of the true pelvis, that is superior to the perineum?
1 - true pelvis
2 - pelvic floor
3 - false pelvis
4 - perineum
2 - pelvic floor
What is the lowest point of the abdominal cavity?
1 - true pelvis
2 - pelvic floor
3 - false pelvis
4 - perineum
2 - pelvic floor
- no superior border so continues into pelvic area
What is the peritoneum?
- tissue that lines your abdominal wall and covers most of the organs in your abdomen
Peritoneum is a tissue that lines your abdominal wall and covers most of the organs in your abdomen. As there is nothing separating the abdominal and pelvic cavities, does the peritoneum cover the whole of the pelvic cavity as well?
- no
- covers the rectum, reflects on the bladder and then back onto the anterior wall of the abdomen
Males and females posses pouches that are created by the folds of the peritoneum. What pouches do men and women have?
- women = rectouterine (between rectum and uterus) and vesicouterine (between uterus and bladder) pouch
- men = rectovesicle (between rectum and bladder) pouch
- vesicle = bladder
- rectouterine also know as pouch of douglas
Males and females posses pouches that are created by the folds of the peritoneum. Women possess:
- rectouterine pouch = between rectum and uterus
- vesicouterine pouch = between uterus and bladder
Which of these pouches is clinically most relevant and why?
- rectouterine pouch (pouch of douglas
- lowest area of the abdomen where fluid collects
Blood supplying the pelvis and abdomen arises from the abdominal aorta. From here the external iliac artery branches, then what is another branch of the external iliac artery that then supplies the pelvic area. What is this branch of the external iliac arteries that supply the pelvic area?
- internal iliac artery
Blood supplying the pelvis and abdomen arises from the abdominal aorta. From here the external iliac artery branches, then what is another branch of the external iliac artery that then supplies the pelvic area called the internal iliac artery. What anatomical landmark does the internal iliac artery branch from the external iliac artery?
1 - sacro-iliac joint
2 - pubic arch
3 - acetabulum
4 - ischial tuberosity
1 - sacro-iliac joint
Where does the internal iliac artery end?
1 - obturator foramen
2 - lesser sciatic foreman
3 - greater sciatic foramen
4 - pubic arch
3 - greater sciatic foramen
- internal iliac artery then bifurcates into anterior and posterior divisions
Which artery does the uterine and vaginal artery branch off?
1 - pudendal artery
2 - external iliac artery
3 - femoral artery
4 - internal iliac artery
4 - internal iliac artery
A hysterectomy is a surgical procedure to remove the womb (uterus). When being a surgeon it is important to understand the blood supply to the uterus, which is the uterine artery, a branch of the internal iliac artery as this will need to be ligated to stop blood loss during the surgery. What can the uterine artery sometimes get confused with, and how can this be avoided?
1 - pudendal nerve
2 - ureter
3 - femoral nerve
4 - internal iliac artery
2 - ureter = a muscular tube emptying the kidneys into the bladder
- distinguish using electrical stimulation, ureter will contract
What does the phrase water under the bridge get used for when performing surgery on the pelvis?
- ureter (containing urine/water) runs underneath the bridge (uterine artery)
Label the veins that drain the female pelvic area using the labels below?
right ovarian vein left ovarian vein left renal vein left common iliac vein left internal iliac vein uterine vein
1 - left renal vein 2 - right ovarian vein 3 - left ovarian vein 4 - left common iliac vein 5 - left internal iliac vein 6 - uterine vein
Label the veins that drain the male pelvic area using the labels below?
left testicular vein left renal vein left internal iliac vein left common iliac vein left external iliac vein inferior vena cava
1 - left renal vein 2 - left testicular vein 3 - inferior vena cava 4 - left common iliac vein 5 - left external iliac vein 6 -left internal iliac vein
The right testicular/gonadal vein drains directly into the inferior vena cava, but the left testicular/gonadal vein drains into the left renal vein. What is the clinical relevance of this?
- renal vein is narrower than vena cava so could be blocked more easily (kidney abscess)
- can present as enlarged gonads or varicose veins (swollen enlarged veins)
What is the lumbar plexus?
- network of nerve fibres
- T12-L4
- supplies the skin and musculature of the pelvis and lower limbs
The lumbar plexus is a network of nerve fibres that supplies the skin and musculature of the pelvis and lower limbs. What vertebrae does this originate from?
- T12 - L4
What is the sacral plexus?
- network of nerve fibres that supplies the skin and muscles of the pelvis and lower limb
The sacral plexus is a network of nerve fibres that supplies the skin and muscles of the pelvis and lower limb. What vertebrae does this plexus originate from?
- sacral spinal nerves S1, S2, S3 and S4
- some innervation from lumbar spinal nerves L4
Where does the sympathetic trunk/chain run in regards to the pelvis?
- left and right chains merge together and form ganglion impar
- anterior to the sacrum
- medial to the anterior sacral foramina
What is the thickest and longest nerve in the body?
- sciatica nerve
The sciatica nerve is the thickest and longest nerve in the body. Where are the nerve roots of the sciatica nerve?
- L4-S3
The perineum is the area between thighs between anus and genitals, and is the most inferior part of pelvic outlet. What is the main nerve of the perineum?
1 - sciatic nerve
2 - inferior gluteal nerve
3 - pudendal nerve
4 - superior gluteal nerve
3 - pudendal nerve
The perineum is the area between thighs between anus and genitals, and is the most inferior part of pelvic outlet. What is the main nerve of the the perineum is the pudendal nerve. Where are the nerve roots of this nerve and the importance of this nerve?
- originates from S2-S4
- main sensory nerve from external genitalia
The perineum is the area between thighs between anus and genitals, and is the most inferior part of pelvic outlet. What is the main nerve of the the perineum is the pudendal nerve. The pudendal nerve originates from S1-S3 and is the main sensory nerve from external genitalia. Which important artery runs alongside this nerve?
1 - pudendal artery
2 - external iliac artery
3 - femoral artery
4 - internal iliac artery
1 - pudendal artery
The perineum is the area between thighs between anus and genitals, and is the most inferior part of pelvic outlet. What is the main nerve of the the perineum is the pudendal nerve. The pudendal nerve originates from S2-S4 and is the main sensory nerve from external genitalia. Why is this nerve so important in relation to operations?
- any perineum surgeries will anaesthesie the region through this nerve
- this is called an episiotomy during vaginal delivery
Label the muscles that originate from the pelvis and provide a soft covering for the pelvis using the labels below:
quadratus lumborum Iliacus transverse abdominas psoas minor psoas major
1 - psoas minor 2 - psoas major 3 - transverse abdominas 4 - Iliacus (sits on the ilium) 5 - quadratus lumborum
Which muscle fills the obturator foreman providing a soft covering and protecting pelvic organs, as per the image below?
1 - Iliacus
2 - obturator internus muscle
3 - psoas minor
4 - psoas major
2 - obturator internus muscle
Which muscle of the pelvis originates at the internal surface of the sacrum and inserts at the superior border of the trochanter of the femur, and thus provides a soft protective layer for the pelvic organs?
1 - piriformis muscle
2 - obturator internus muscle
3 - psoas minor
4 - obturator externus muscle
1 - piriformis muscle
Labels the 4 key joints of the pelvis?
sacro-iliac joint
pubic symphysis
lumbosacral joint
hip joints
1 - lumbosacral joint
2 - sacro-iliac joint
3 - hip joints
4 - pubic symphysis joint
The sacro-iliac joint is a very strong joint, but when may this joint become excessively stressed?
- during pregnancy
- during menopause
Where does the lumbosacral joint meet and what type of joint is this?
- L5 and S1 (lumbar has 5 and sacrum has 5 vertebrae)
- symphysis joint which is a cartilaginous joints composed of fibrocartilage
What type of joint is the sacroiliac joint?
- a synovial joint formed between the ilium and the sacrum
- contains synovial fluid with synovial membrane
What can change the sacroiliac joint?
- pregnancy
- release of hormones
- age
If there is excessive strain placed on the sacro-iliac joint, what other joint in the pelvis can this then be transferred into?
- pubic symphysis joint causing significant pain
- should be no movement here
The pubic symphysis does not allow any movement under normal conditions. What type of joint is this?
1 - suture joint
2 - cartilaginous joint
3 - fibrocartilaginous joint
4 - hyaline joint
2 - cartilaginous joint
The pubic symphysis does not allow any movement under normal conditions as it is a secondary cartilaginous joint. Under what 4 conditions can their be dysfunction of the pubic symphysis?
- before and during menstruation (less stable and injury prone)
- pregnancy increases hormones andH2O absorption and increases laxity, thus increasing risk of injury
- menopause
- abnormal weight loading
During pregnancy there is an increase in hormones and H2O absorption, which increases laxity, thus increasing risk of injury in the pubic symphysis. How long should it be before the pubic symphysis returns to normal following pregnancy?
1 - 6-12 days
2 - 6-12 weeks
3 - 6-12 months
4 - 6-12 years
2 - 6-12 weeks
What is cephalopelvic disproportion?
1 - pelvis is deformed during pregnancy
2 - pelvis has increased in size during pregnancy
3 - babies head is too large to fit through mother pelvis
3 - babies head is too large to fit through mother pelvis
