we do the thorax and axilla as well. The shoulder
joint, a lot of theory. I haven't cover
it but you need to just go through the slides
when you have a minute. You can get questions
on the rotator cuff, shoulder joint. You need
to understand the glenoid labrum. From the
superior part, you have the long head of biceps.
From the inferior side, you have the long
head of triceps. So, that is the theory. The
four muscles of the rotator cuff, you need
to know. Painful arc syndrome. Painful arc
syndrome is when your supraspinatus tendon
gets caught under the acromion process.
So supraspinatus initiates the first 15
degrees of abduction. Then the deltoid takes
over. Until here is deltoid, and how does
this movement happen? Which muscle is working?
Supraspinatus deltoid --
Trapezium? Yes, very good, and a bit more?
You’re on the right track. Trapezium, it’s
by the rotation of the scapula.
Lattisimus? That doesn’t work.
Trapezium is mainly.
Beyond this, this gives the scapula rotation
rotating on the thorax and this trapezium
is pulling it up. It’s also aided by the
rhomboids. This is your action of the shoulder.
But if we have a supraspinatus tendinitis
or painful arc syndrome, when it comes to
60 degrees, the supraspinatus tendon gets
caught under the acromion process.
It’s painful, painful, painful all the way up to
120. Now, when you push it more, the tendon
moves off the acromion process and it becomes
pain free. So that is your painful arc syndrome,
60 to 120 degrees. Brachial plexus, you can get
this in any book.
So that’s why I didn’t go through this,
but when you’re revising, you’ll be able
to get all this information for you to understand axillary artery,
what is on the lateral side, what is on the medial side
branches of the lateral cord, posterior cord, branches
of the medial cord. Just take a minute for
you to orient yourself. You have a lateral
cord of the brachial plexus there, axillary
artery, medial cord of the brachial plexus,
and then you have the ulnar nerve here,
One anatomical relation they’ll ask you in
the exam is, if you go back to the cubital
fossa, the most medial structure is the median
nerve. Next to that is the brachial artery,
but if you go up the arm, if you go up here,
it's other way around. So the brachial artery
is medial, median nerve is lateral. As it
comes to the distal one-third of the arm,
they cross over so that the median nerve comes
most medial. So that is another anatomic relation.
Okay. Dermatomes, I’m sure you know this,
but I think I have a picture on that. Okay.
So, you know that is C5, C6. C6 is your thumb and half
of the index finger. C7 is middle finger.
C8 is mainly ring and little. T1, T2. So, C5
to T2 in the limb. If you look here, it will
be T3, T4, T5, T6, T7, T8, T9, umbilicus is
T10. T11, T12, L1. C3 and C4, where do the
C3 and C4 come from?
Very good, yes. This is what we’ll be discussing
after the break. When we discuss the head
and neck, we’ll cover the C3, C4. So as
I said, the brachial plexus is starting from
C5. So that’s why the entire arm is C5 to
T1, the inside part is T2. Okay. Cubital fossa,
that’s a schematic head of presentation. Laterally,
you have the brachioradialis. Medially, you
have the pronator teres. So, this is the left and
the right cubital fossa. Brachioradialis.
Pronator teres. Median nerve. Brachial artery.
Cephalic vein. That’s the tendon of biceps.
So if you look at, that’s your left arm,
medial to lateral, pronator teres, median nerve,
brachial artery, biceps, brachioradialis.
Okay. There is nothing new. This is just a
theory of what we've discussed, their boundaries,
contents. Carpal tunnel, we’ve been through
it in detail, but this is cross-section. This
is all for further understanding and revising
if you have the time. But as I said, if you
just revise what we have covered this morning,
that should be sufficient for your exam.