Repro Session 5 Flashcards
What are the bony landmarks that are palpable O/E of the pelvis?
Iliac crest, linea terminalis, ischial spine and ischial tuberosity
What is the promontory?
Anterior superior edge of the 1st sacral vertebra
What is the false pelvis?
Above linea terminalis where a foetus of any size can be accommodated
What is the true pelvis?
Bony canal below linea terminalis that is solid and immobile
What allows a small amount of laxity in the true pelvis during pregnancy?
Hormones acting on the pubic symphysis
What are the two ligaments of the pelvis?
Sacrospinous and sacrotuberous
What is the pelvic inlet?
Boundary between the greater and lesser pelvis determining the size and shape of the birth canal
What are the alternative names of the pelvic inlet?
Linea terminalis and iliopectineal line
Where is the plane of greatest diameter in the pelvis?
From mid pubic symphysis to IV disc of S2/3
Where is the plane of least diameter found in the pelvis?
Inferior pubic symphysis to between S5 and coccyx (obstetric conjugate)
Where is the pelvic outlet found?
At the end of the lesser pelvis at the beginning of the pelvic wall
How is the pelvic outlet increased in pregnancy?
Hormones increase laxity of sacrotuberous and allow movement of the coccyx
What is assessed in the midpelvis on clinical examination?
Straight side walls and bispinous diameter (between ischial spines)
What is assessed at the pelvic outlet on clinical assessment of the pelvis?
Infrapubic angle and distance between ischial tuberosities
What is the obstetric conjugate?
Sacral promontory to midpoint of pubic symphysis
What is the diagonal conjugate?
Sacral promontory to inferior pubic symphysis
Which conjugate is used clinically to assess AP diameter of the pelvis and why?
Diagonal as the inferior pubic symphysis can be palpated
What are the differences between a gynecoid and android pelvis?
Gynecoid has wider ilium, flared alar, larger and more circular pelvic inlet, small ischial spines, straight side walls, larger sub-pubic angle, well curved sacrum and larger sciatic notch
What makes up the lateral border of the pelvic inlet?
Iliopectineal line
What forms the anterior border of the pelvic inlet?
Public symphysis
What forms the posterior border of the pelvic inlet?
Sacral promontory
What forms the anterior border of the pelvic outlet?
Pubic arch (inferior border of ischiopubic rami)
What forms the lateral border of the pelvic outlet?
.
Ischial tuberosity and sacrotuberous ligament
What forms the posterior border of the pelvic outlet?
Tip of coccyx