Lecture 16 - Pelvic Girdle Flashcards
List the functions of the pelvic girdle
- Connect lower limbs to the axial skeleton
- Transfer weight from axial skeleton to lower limbs
- Provide attachment sites for strong muscles of gluteal and abdominal regions
- Provide support for pelvic organs
What bones make up an individual hip bone?
- Ilium
- Ischium
- Pubis
What bones make up the pelvic girdle?
- Right and left hip bones
- Sacrum
Which bone from the pelvic girdle is classified as both axial and appendicular?
Sacrum
What is the socket for the head of the femur called? What bones contribute to it’s formation?
Acetabulum = ilium, ischium, and pubis
How many vertebrae fuse to make up the sacrum?
5 vertebrae
What is the sacral canal?
- Continuation of the vertebral canal
- Contains the cauda equina
What does the sacral foramina allow?
Allows nerves to exit the sacral canal
What is the cauda equina?
A bundle of spinal nerves that descend past the distal end of the spinal cord
Male Pelvis vs. Female Pelvis:
Compare General Structure
- Male: Thick and heavy
- Female: Thin and light
Male Pelvis vs. Female Pelvis:
Compare Pelvic Inlet
- Male: Heart shaped, narrow
- Female: Oval and Rounded, wide
Male Pelvis vs. Female Pelvis:
Compare Subpubic angle
- Male: Narrow
- Female: Wide
Male Pelvis vs. Female Pelvis:
Compare Greater Sciatic Notch
- Male: Narrow, inverted V shape
- Female: Wide, almost 90 deg.
In Anatomical Position, the ____ and the ____ lie in the same vertical plane
the ASIS and the pubic symphysis
What does the position of the pubic symphysis allow it to do?
support the weight of the bladder and other pelvic organs (including uterus during pregnancy)
Name the ligaments that resist the rotation of the pelvis
- Sacrotuberal ligament (STL)
- Sacrospinous ligament (SPL)
The sacroiliac joint is classified as what type of joint?
Compound Joint:
- anteriorly: synovial
- posteriorly: syndesmosis (less mobile)
Where is the fibrocartilagenous interpubic disc found?
Between the 2 pubic bones
Which ligament(s) reinforce the pubic symphysis?
- superior pubic ligament
- inferior pubic ligament
Where do the left and right pubic bones articulate?
at the pubic symphysis
What happens at the sacral plexus?
sacral spinal nerves (S1-S5) exit the intervetebral foramina and their anterior rami form a plexus of nerves within the psoas major muscle
List the terminal branches found at the sacral plexus
- Superior gluteal nerve
- Inferior gluteal nerve
- Nerve to quadratus femoris
- Nerve to obturator internus
- Nerve to piriformis
- Sciatic nerve (common fibular nerve and tibial nerve)
Which roots form the lumbosacral trunk?
L4 and L5 roots
Which roots unite with the lumbosacral trunk to form the large sciatic nerve?
S1, S2, S3
