Aldridge - Structure Of Pelvic Wall Flashcards
Anterior-superior margin of vertebra S1
Sacral promontory
Caudal most part of the vertebral canal
Contains cauda equina
Sacral canal
Inferior opening to sacral canal
Potential site of needle entry for epidural anesthesia
Sacral hiatus
The sacroiliac joint is held together by what ligaments?
Interosseous ligaments
Anterior and posterior sacroiliac ligaments
Strong accessory ligament from transverse process of L5 to iliac crest
Iliolumbar ligament
These two ligaments prevent the sacrum and coccyx from rotating posteriorly due to weight of trunk
Sacrotuberus
Sacrospinous ligaments
Window for neuorvascular structures and piriformis muscles to pass from true pelvic region into the gluteal region
Great sciatic foramen
Region for neurovascular structures and obturator internus muscle to pass from gluteal region to the perineum
Lesser sciatic foramen
What structures make up the pelvic outlet? (X5)
Pubic symphysis
Ischial tuberosity
Tip of coccyx
Sacrotuberous ligament
Inferior ramus of pubis
What is the diagonal conjugate diameter?
It is a measurement taken fro the inferior border of the pubic symphysis to the sacral promontory
Measures anterior-posterior diameter of the birth canal
What is the transverse diameter of the pelvic outlet?
Measurement of the birth canal taken between the two ischial tuberosities
What is the maximal measurement of the pelvic inlet?
Its transverse diameter
Bc of baby’s head position during parturition
What is the maximum measurement of the pelvic outlet?
Anteroposterior diameter
During partuition, the head of the baby must rotate _____- degrees between pelvic inlet and outlet
90
What forms the lateral wall of the true pelvis?
Innominate bone (below pelvic brim)
Obturator internus muscle (and fascia)
Sacrospinous and sacrotuberous ligament.
What forms the anterior wall of the true pelvis?
Pubic symphysis
Bodies of pubic bone
What forms the posterior wall of the true pelvis?
Piriformis muscle
Region below pelvic diaphragm
Contains external genitalia and outlet of gut and urogenital system
Perineum
What happens if you tear the perineal body (a small mass of CT in the pelvic diaphragmm that is a point of insertion for many muscles)
You can get prolapse
This structure is important in maintaining support of the pelvic viscera
The sacral nerves emerge from the sacral canal via ______
Anterior sacral foramina
Branches of the sacral plexus that exit the true pelvis thru the greater sciatic foramen (x4)
Superior gluteal nerve
Inferior gluteal nerve
Sciatic nerve
Posterior cutaneous nerve of thigh
