Pelvis I Flashcards
What are the bones of the pelvic girdle
Os Coxae (ilium, ischium, pubis)
Sacrum
Coccyx
What are the regions of the ilium
ASIS
PSIS
Iliac crest
Iliac Fossa
What are the regions of the ischium
greater sciatic notch, ischial spine, lesser sciatic notch, ischial tuberosity, ischial ramus
How does the sacrum connect to the ilium
Sacroiliac joints
How are the ischium and pubis connected
Superior pubic ramus, inferior pubic ramus, ischiopubic ramus, ischial ramus
What is found at the base of the sacrum
L5/S1 level is the sacral promontory
What forms the pubic arch
ischiopubic rami connecting
Where do the nerves enter the pelvis
They go through the posterior foramina and exit through the anterior foramina of the sacrum
How many vertebrae are in the Coccyx
4 fused vertebrae that connect to the sacral apex (S5) at the sacrococcygeal joint
What are the ligaments of the pelvis
Anterior sacroiliac ligament
Posterior sacroiliac ligament
Interosseous ligament
What is the sacrospinous ligament
connects the sacrum to the ischial spine (more anterior)
What is the sacrotuberous ligament
Connects the sacrum to the ischial tuberosity (more posterior)
How can you tell a female from a male pelvis
- Females have a wider pelvic inlet than males (wider ischial tuberosities and ischial spines) (round in women, heart shaped in men)
- Females have a wider subpubic angle (>80 degrees) than men (<70 degrees)
- Sacral promontory protrudes less in females than in men
What muscles form the posterior and lateral walls of the pelvis
Piriformis (through greater sciatic foramen) Obturator interns (lateral wall)
What sits on the anterior aspect of Piriformis
sacral plexus
What is the purpose of ligaments
To help resist rotation
What are the muscles of the pelvic floor
Levator ani (pubococcygeus + iliococcygeus) Coccygeus (internal surface of sacrospinous
What does the pelvic diaphragm separate
Superior: pelvic viscera
Inferior: perineum
What are the regions of Pubococcygeus
Pubovaginalis
Puboprostaticus
Puborectalis
What provides major innervation of the pelvic muscles
Piriformis: sacral plexus
Obturator interns: sacral plexus
Pelvic diaphragm: sacral and lumbar plexus
What can weakness in the pelvic diaphragm lead to
urinary incontinence, bowel incontinence, prolapse of the pelvic viscera
What provides venous drainage to the pelvis
veins named similarly to the arteries. As well as multiple venous plexuses
What are the venous plexuses
Prostatic plexus Uterine plexus Vaginal plexus Rectal plexus Vesical plexus
What is the flow of lymph drainage in the pelvis
internal iliac nodes–> common iliac nodes–> lumbar lymph–>chyle cistern–> thoracic duct
What is the only exception to pelvic lymph drainage, and what is the flow
ovaries and testis drain directly to the lumbar lymph nodes–>chyle cistern–> thoracic duct
What is the primary blood supply to the pelvis, perineum, and gluteal region
internal iliac arteries
What are the major branches off the internal iliac artery
Superior gluteal Inferior gluteal Internal Pudendal (inferior rectal) Umbilical (superior vesical) Obturator Inferior vesical Middle Rectal Uterine Vaginal
Which artery has potential for injury during inguinal hernia repairs
Aberrant obturator artery (20% of people have it) that arises from inferior epigastric artery
Where does the aberrant obturator artery run
over the superior pubic ramus
How many degrees is the pelvic inlet tilted from the horizontal plane
55 degrees
How many degrees is the pelvic outlet tilted from the horizontal plane
15 degrees
