Let’s look at some muscle anatomy in
the pelvis on CT scans.
What are these muscles?
Psoas muscles
Which are the muscles that you
are starting to see in front of and
behind the iliac bones?
Gluteus medius
Iliacus
Can you idendify the abdominal
muscles at this level?
Rectus abdominis
External oblique (superficial)
Internal oblique (middle)
Transversus abdominis (deep)
What muscle are we starting to get into
just posterior to the gluteus medius?
This is the gluteus maximus (it
doesn’t look very maximus at this
level it gets larger more inferiorly)
At this level you start to see the iliacus
and the psoas coming together and we
also start to get into the third gluteal
muscle.
This is the gluteus minimus
Which muscles are these?
Piriformis muscles
Which major nerve is this?
Sciatic nerve
This is where the sciatic nerve
comes out of the greater
sciatic foramen. What are the
anatomic boundaries of the
greater sciatic foramen and
what comes out of it?
What is the name of this muscle?
Sartorius
What is the origin of this muscle?
Anterior superior iliac spine. You can
see it if you follow the muscle 4
slices superiorly.
Which muscle is this?
Hint, it is the only member of the quad
group to cross both the hip and the
knee joint.
Rectus femoris
What is the origin of the rectus
femoris?
Anterior inferior iliac spine, which
you can see if you trace the muscle
2 images superiorly.
What portion of the bony pelvis is the
arrow pointing to?
Hint you are sitting on it right now.
Ischial tuberosity
Which flexor of the knee attaches
here?
The hamstrings
Which is this lateral muscle?
Hint, if you trace it back it has the
same attachment point as the
sartorius on the anterior superior
iliac spine.
Tensor fascia lata
This is a normal x-ray
of the hips. Not the
joint space between the
femoral heads and the
acetabulae.
This is a patient with osteoarthritis
in the left hip. Not there is no joint
space in the superior aspect of the
hip joint.
There is also sclerosis (increased
density in the bone) above the
joint space characteristic of
osteoarthritis.
There is also osteophyte
formation (bony production on
the edges of the joint-arrow).
This is also commonly seen in
osteoarthritis.
These are 2 different types of hip
prostheses in this patient with bilateral
total hip replacements.
This is a normal
view of the
pelvis. When
looking for
acetabular
fractures there a
few lines to look
at.
This is the
iliopubic line
which outlines
the anatomic
anterior
column
This is the ilioischial line which
outlines the anatomic
posterior column.
This is a Judet view
(oblique view) of the
pelvis which better
illustrates the
columns of the
acetabulum.
Can you find the
anterior column
(iliopubic line)?
Can you identify
the posterior wall
This is the opposite
oblique. Can you
find the region of the
posterior column?
Can you identify
the anterior wall/lip
of the right
acetabulum
This is a case with an
acetabular fracture.
Do you see disruption
of one of the
columns?
The anterior
column is disrupted
This is another
oblique view. Do
you see disruption
of one of the
columns?
The posterior
column is
disrupted
Anterior
Posterior
On the left you see a view looking
from the outside of the pelvis. The
acetabulum is the dark structure in
the middle (arrow). The fracture line
shows how a posterior column
fracture runs
On the right you see a sagittally
reformatted CT (oriented the same way as
the anatomic drawing to show the fracture
line of a posterior column fracture.
Anterior
division
Posterior
division
These are consecutive sagittal
images illustrating the anterior
and posterior divisions of the
internal iliac artery. Can you try
and identify the superior and
inferior gluteal arteries.
This is a 3D reformatted
images of the CT angiogram
from the previous slide. The
arrow points to the posterior
division of the internal iliac
artery.
Can you see why the
superior gluteal artery
could be injured with a
posterior column
fracture?
Fracture plane of a
posterior column
fracture