Pelvis and Perineum Flashcards
Describe the pelvis
Basin-shaped, caudal end of body cavity Continuous with abdomen above, surrounded by bony pelvis, limited below by pelvic floor/diaphragm
Describe the perineum
Area inferior (superficial) to pelvic floor, bounded by pelvic outlet, limited inferiorly by the skin.
What separates the pelvic cavity from the perineum?
Pelvic floor (muscular sheet)
Pelvis labels (superior view) –> NEED TO KNOW
Pelvis labels (medial surface) –> NEED TO KNOW
What is the sacroiliac joint (x2)?
Connects the sacrum to the ilium bones of the pelvis
What 3 parts is the hip bone comprised of? Together, what do these 3 parts form?
- Ileum 2. Pubis 3. Ischium A cup-shaped socket known as the acetabulum
What articulates with the acetabulum?
Head of the femur
Describe the ilium
The widest and largest of the three parts of the hip bone, and is located superiorly.
Which part of the acetabulum does the ilium body form?
Forms the superior part of the acetabulum (acetabular roof)
Describe the ilium
The widest and largest of the three parts of the hip bone, and is located superiorly.
What are the 2 surfaces of the wing of the ilium?
- Inner surface 2. External surface
Immediately above the acetabulum, what does the ilium expand to form?
The wing (or ala)
Describe the external surface of the wing of the ilium
(Gluteal surface) – has a convex shape and provides attachments to the gluteal muscles.
What does the superior margin of the wing form?
Thickens to form the iliac crest
Where does the iliac crest extend from and to?
It extends from the anterior superior iliac spine (ASIS) to the posterior superior iliac spine (PSIS).
What indentation is found on the posterior aspect of the ilium?
Greater sciatic notch.
How is the ASIS an important anatomical landmark?
- Mid-inguinal point 2. Mid-point of the inguinal ligament
Describe the mid-inguinal point
Halfway between the ASIS and the centre of the pubic symphysis The femoral artery can be palpated here
Describe the mid-point of the inguinal ligament
Halfway between the ASIS and the pubic tubercle.
Describe the pubis
The most anterior portion of the hip bone
What are the 3 parts of the pubis?
- Pubic body 2. Superior pubic ramus 3. Inferior pubic ramus
What does the pubic body articulate with?
With the opposite pubic body at the pubic symphysis
What is the superior aspect of the pubic body marked by?
A rounded thickening (the pubic crest), which extends laterally as the pubic tubercle.
Together, what does the superior and inferior rami enclose?
Part of the obturator foramen
What passes through the obturator foramen?
The obturator nerve, artery and vein pass through to reach the lower limb.
Describe the ischium
Forms the posteroinferior part of the hip bone. Much like the pubis, it is composed of a body, an inferior ramus and superior ramus.
What does the inferior ischial ramus combine with? What does this form?
The inferior ischial ramus combines with the inferior pubic ramus forming the ischiopubic ramus, which encloses part of the obturator foramen. NEED DIAGRAM
Together, what does the superior and inferior rami enclose?
Part of the obturator foramen