Pelvic Anatomy Flashcards
Name the fxns of the pelvis.
- upper body support
- external genitalia attachment
- passage of childbirth
- protection of pelvic organs, blood and nerve supplies, their venous and lymphatic drainage
- transfer of the weight to 2 femurs from vertbral colum
What does the bony pelvis consist of?
2 Hip bones
SACRUM
COCCYX (NOT part of pelvic girdle)
What is the hip bone made of?
(iluim-superiorly, ischium and pubis)
- -fuses at AGE 4-8 at the ACETABULUM (triradiate)
- —pubis fuses later at 17 for females
The big tubercle of the the ischium
—what you sit on
ichial tuberosity
What the superior opening of the pelvis?
pelvic inlet
What are the boundaries of the pelvic inlet?
- sacral promontory (prominent sacral bit)
- ilium
- superior pubic ramus
- pubic symphysis
What are the boundaries of the pelvic outlet?
- pubic symphysis
- ischiopubic ramus
- ischial tubersosity
- sacrotuberous ligament
- coccyx
Where is the pelvic cavity?
- between the pelvic INLET and the PELVIC floor
What is the greater/false pelvis?
- larger area above the true pelvis
What does the pelvic floor seperate the pelvic cavity from?
the perineum
What is the palpable parts of the pelvis?
- iliac crest
- pointy bit -ASIS
- PUBIC symphysis
- ischial spines are papable on vaginal examination at 4 and 8 o’clock position (important in PV birth)
- ischial tuberosity
- coccyx a the start of the gluteal cleft
Name the synovial joints of the hip.
- hip joint
- sacroiliac joint (only anterior aspect—posterior is fibrous)
Name a secondary cartilaginous joint.
Pubic symphysis …minimal flexibility
Name 2 important ligament in the pelvic region.
sacrotuberous (ichial tuberosity)
sacrospinous (ischial tuberosity)
What formaninae do the ligaments form and what is the purporse?
– they form the greater and lesser sciatic foraminae ——-important passage ways for nerves and vessels
What covers the obturator formamen?
- obturator membrane
- fully covered except a little superior bit —-OBTURATOR canal —passing of obturator NERVE and vessels
What covers the obturator formamen?
- obturator membrane
- fully covered except a little superior bit —-OBTURATOR canal —passing of obturator NERVE and vessels
What life threatening consequence may arise from fracture of the bony pelvis?
- hemorrhage of common iliac artery and vein!!!
- OTHERS: damage to sacral plexus
- damage to pelvic organs
What is the diff. between a male and female pelvis?
- AP and transverse diameters of the female pelvis is LARGER in the female at both INLET and OUTLET
- subpubic ARCH and angle is bigger in female
- much shallow pelvic cavity in the female
What are the soft spots of the baby skull?
- anterior and posterior FONTANELLE
- anterior closes in 18 months-2 years
What is meant by moulding of the baby skull ?
- the movement of one bone over another to allow the fetal head to pass through the pelvis
What is the vertex of the baby’s skull?
- diamond shape between the 2 PARIETAL eminences
and the A and P fontanelle - important to palpate the bby’s skull to know the orientation of the bby’s skull
What is the importance of the occipitofrontal diameter of the baby’s skull?
- the occipitofrontal diameter is LONGER than the biparietal diameter
- should therefore lie in line with the transverse diamter—-easier for it to leave the cavity
WHy does the baby’s head have to turn towards the end of the labor?
- –in order to leave in an OA (occipitoanterior position) because the AP becomes the longest bit
- bby’s neck should be flexed and then extended
When does the third rotation occur in labour?
- once the baby’s head is delivered
- to allow the delivery of the shoulders and then the rest of the body
What is referred to as the station baby during delivery?
- distance of the fetal head from the ischial spine
- a negative number means the head is SUPERIOR to the ischial spine
Describe the change in the orientation of the foetal head throughout child birth.
- At pelvic inlet: fetal head should be TRANSVERSE
- As it descends through the pelvic cavity, foetal head should ROTATE and should be flexed.
- A the pelvic OUTLET= fetal head should lie in OA and extension of the head should occur.
