Couple of other important things.
The phrenic nerve is quite important.
They can ask you coarse, relations, root value.
Root value of phrenic is C3, C4, C5. Similar
to the brachial plexus I said, it comes out
laterally, then where does it go? In terms
of relations. Any ideas in terms of
relation to scalene muscle, in relation to
Anterior to the scalene muscle.
It’s anterior to the scalene muscle, so
this is one question they ask, anterior to
the scalene and it’s anterior to subclavian
artery. It’s anterior to the subclavian
but posterior to the subclavian vein. So in
the neck, the phrenic nerve, just remember
this way: phrenic is quite lateral and vagus
is very medial, vagus is towards the midline.
Vagus is very much close to midline.
Phrenic is quite lateral, so phrenic is overlying
the scalenius anterior muscle. That’s
the scalene, that's scalenius anterior.
So this is your scalene, that’s
the subclavian artery, so subclavian, that’s
your right side, you’re looking from there,
scalenius anterior, scalenius medius, subclavian
artery. And your subclavian vein is in front
of artery. And phrenic nerve is lying
here or in front of the subclavian artery,
in front of the scalenus anterior. Then
the phrenic nerve comes, arches over, it lies
on the heart. Then you have the right phrenic
and the left phrenic. Right phrenic accompanies
Inferior vena cava.
Inferior vena cava. The right phrenic accompanies
inferior vena cava, pierces the diaphragm
at the level of T10 vertebra.
That is your inferior vena cava and the right
phrenic. The left phrenic nerve has got its
own hiatus in the diaphragm, so it’s got
its own hiatus and supplies the diaphragm.
So that’s all you need to remember about
phrenic. So, you know the questions we have
seen are always rehashed: root values asked,
what’s the relation to the subclavian artery,
what’s the relation to the scalene muscle
and how does the right and the left go.
This is what they can ask you. Vagus?
The hiatus of the vena cava T10? Not T8?
No no, vena cava is T8, esophagus is T10 and
aorta is T12.
Vagus. Vagus is the 10th cranial nerve, comes out through
the jugular foramen, lies within the carotid