Level 2 - Pelvis Flashcards
What is the pelvic girdle composed of?
-sacrum
-two coxal bones
-bound tightly by ligaments
What are the 3 bones that fuse together to form each coxal (innominate) bone?
-ilium (largest and upper most)
-ischium (strongest and lowermost)
-pubis (most anterior)
Where does the bladder sit?
Right behind the symphysis pubis
Irregular shaped bones in which the head of the femur articulates with the acetabulum
Innominate hip bone (coxal)
-Most superior part of the innominate bone
Ilium
Wide flattened plate of the ilium with long curved superior border
Iliac crest
What muscles attach to the external surface of the ilium?
Gluteal muscles
What vertebral level will the highest part of the iliac crest be?
Around level L4
Where does the curve of the iliac crest end?
Anteriorly
ASIS
anterior superior iliac spine
T/F
The anterior border of the ilium continues to the AIIS, anterior inferior iliac spine
True
(Lies just superior to acetabulum)
What are the names for the coxal bone?
-coxal
-innominate
-pelvic
Where does the crest of the ilium curve to posteriorly?
PSIS
posterior superior iliac spine
What lies below the PSIS?
PIIS
posterior inferior iliac spine
Where is the greater sciatic notch situated?
Below the PIIS
*triangular notch
What is on the internal surface of the innominate bone?
Iliac fossa
*large shallow concave surface
Where do the ilium and pubis meet?
Iliopectineal (iliopubic) eminence
T/F
The medial border runs obliquely down across the ilium bone to the iliopectineal eminence
True
Border between true and false pelvis
Arcuate line
Where on the ilium is the articulating surface for the sacrum?
Just superior to the sciatic notch
Forms the inferior and posterior parts of the innominate bones
Ishium
What two sections is the ishium split into?
Body and ramus
Upper portion of ischium, forms the greater sciatic notch and has the ischial spine, then below the ischial spine is the lesser sciatic notch
Body of ischium
Where is the ischial tuberosity located?
On the body of the ischium
Lower curved portion of the ischium that joins with the inferior portion on the pubis
Ramus of ischium
Where is the obturator foramen situated?
Inferior to the acetabulum
What is the obturator foramen enclosed by?
Body of ischium, ischial ramus, superior and inferior rami of the pubis
T/F
The greater sciatic notch is made up of both ilium and ischium
True
Forms the anterior part of the innominate bone
Pubis
What is it called where the two pubis from each side join?
Symphysis pubis
What are the 3 parts of the pubis?
Body, superior ramus, inferior ramus
What part of the pubis is flat, extends to opposing body and is joined by cartilaginous disk at the symphysis
Body
What part of the pubic body has a rounded upper border that projects forward?
Pubic crest
T/F
The pubic tubercle is located on the external surface of body of the pubis, and is an attachment for a ligament
True
Part of the pubis that extends laterally and slightly up to join the ilium and ischium at the acetabulum
Superior ramus
Part of pubis that passes back, down, and laterally to join the ramus of the ishium
Inferior ramus
A hemispherical cavity on the lateral surface of the coxal or innominate bone
Acetabulum
What 3 parts contribute to the acetabulum?
Ilium, ischium, pubis
Which way is the acetabulum directed?
Laterally, down, forward
T/F
The acetabulum is surrounded by a prominent bony rim which is deficient inferiorly (acetabular notch) and enhanced by a cartilaginous rim (to deepen socket)
True
If hip is dislocated, which direction will it most likely go?
Inferior
Because of acetabular notch
T/F
The middle part of the acetabulum is not covered in cartilage
True
(Fovea of femur articulates)
What causes the hip joint to be very stable?
-The shape of the head of the femur, and the acetabulum
-joint capsule and ligaments contribute to the joints stability
What movements do the hip joint (synovial, ball and socket) allow for?
Flexion, extension, abduction, adduction, rotation, circumduction
What are the articular surfaces of the hip joint?
Head of femur, acetabulum of innominate bone
What type of joint is the symphysis pubis?
Amphiarthroses, cartilaginous symphysis
Articular surfaces: pubic bodies and articular disc
Movements: slight movement (minimal) with pressure
What type of joints are the sacroiliac joints?
Synovial plane (gliding)
Articular surfaces: surfaces of ilium and sacrum
Movement: small rotational, gliding movement
What is the appearance of the sacroiliac joints?
Bony and rough
Ilium and sacrum surfaces are not smooth
What two parts is the pelvis divided into?
Greater pelvis (false pelvis)
Lesser pelvis (true pelvis)
It is above the pelvic brim and is part of the abdomen
Greater pelvis / false pelvis
It is below the pelvic brim. Smaller in size. Contains the reproductive organs, urinary bladder, pelvic colon and rectum
Lesser pelvis / true pelvis
What divides the greater pelvis from the lesser pelvis?
Iliopectineal line
Sacral promontory, anterior border of ala of the sacrum, iliopectineal line of the ilium and ischium, pubic crests and the superior border of the symphysis pubis
Pelvic inlet - boundaries
A canal from the pelvic inlet to the outlet. Deeper posteriorly. Contains pelvic organs.
Boundaries : anterior pubic bones, posterior sacrum and coccyx, lateral ilium and ischium
Pelvic cavity
Indented by ischial tuberosities, ischial spines and the sacrum and coccyx.
Boundaries : apex of sacrum, ischial tuberosities, ischial rami, inferior pubic rami and inferior border of symphysis pubis
Pelvic outlet
Deep and funnel shaped with narrow pubic arch
Male pelvis
Shallow, broad, and flaring with a wider pubic arch
Female pelvis
-bones are larger and stronger
-false pelvis is narrower
-inlet of true pelvis is narrower and triangular
-ischial spines are closer together, therefore narrower outlet
-pubic arch is narrower (pubic angle)
Male pelvis
