Transcript Shoulder Anatomy

Shoulder Anatomy
This is an axial T1 MRI image at
the top of the shoulder. All
structures look dark because of fat
suppression. We use fat
suppression with T1 images
because for this study we injected
contrast into the joint. Fat
suppression is commonly used
after contrast is given on MRI to
increase the conspicuity of the
contrast material as you will see
on later images.
This is a lower sequential axial
image just above the shoulder
joint.
What muscle (arrows) and tendon
(arrowheads) are these?
The supraspinatus muscle and
tendon.
We are starting to get down to
the joint space do you see the
white contrast.
Anterior
Lateral
Note the anterior, lateral and
posterior heads of the deltoid.
Posterior
This image is further inferior, do
you see the coracoid process?
Remember this is an anterior
structure.
Do you remember the
attachments onto the
coracoid process?
The coracobrachialis and the
short head of the biceps
muscle. Also the pectoralis
minor attached to the coracoid
process.
Can you find the subscapularis
tendon on this image?
What articular part of the
scapula articulares with the
humerus?
This is the glenoid
Can you find the
fibrocartilagenous glenoid
labrum?
What is the function of the
glenoid labrum?
To add surface area and provide
stability to the glenohumeral joint.
Where does the labrum tear with
an anterior shoulder dislocation?
Hard question
Anteriorly and inferiorly
Anterior
labrum
Posterior
labrum
Do you see this patients’ anterior
inferior labral tear?
There is high signal between the
anterior and inferior labrum and
the bony glenoid characteristic of a
labral tear. This case was kind of
subtle, so we put the patient in an
abducted externally rotated arm
position to displace the torn
labrum.
Here you can better see contrast
between the labrum and glenoid.
This is the final image in this axial set.
What is this black structure between
the greater and lesser tuberosities
surrounded by contrast?
This is the long head of the biceps
tendon in the bicipital groove. It is
common to have contrast
surround this structure as it
passes through the shoulder joint
before it inserts onto the suoperior
labrum.
This is a coronal proton
density image starting in
the posterior aspect of
the shoulder. What
bone is marked by the
arrows?
This is the acromion
What posterior rotator
cuff muscle are marked
by the upcoming
arrows?
Teres minor
Infraspinatus
What posterior rotator
cuff tendon is marked
by the arrows?
Infraspinatus tendon
What is this ligament
attaching onto the
acromion?
Hard question
Coracoacromial
ligament
What lateral muscle is
this?
Deltoid
Take a look at this mid
coronal image though
the shoulder joint. You
see the glenoid and
humerus as if you are
looking at a frontal x-ray
Can you find the
supraspinatus muscle?
How about the
trapezius muscle?
As we are more
anterior here, can you
trace the intraarticular
portion of the long head
of the biceps tendon as
it inserts onto the
superior labrum?
On this anterior image
can you find the short
head of the biceps
tendon as it attaches to
the coracoid and the
subscapularis tendon?
Short head of biceps
tendon
Tendon of
subscapularis
Can you see the
neurovascular
structures in the
anterior aspect of the
axilla?