I'm now going to demonstrate the deep
tendon reflexes and doing the reflexes
is important to position the patient
it's important to know the level that
you're testing and it's important to
have the right tools in order to get the
reflex we use a queen square hammer we
give this to all our incoming interns I
think it has a nice flex to it and is
really good tool to get the reflex even
though you can get it in other ways we
recommend this I'm going to begin with
the brachioradialis reflex I'm going to
tap on the tendon not so much on the
muscle and this is a C 5,6 reflex
I'm also going to the biceps reflex by
putting my hand on the biceps tendon and
then I'm going to strike my thumb and I
will feel the contraction as well as
perhaps see the muscle contract I think
one important caveat is that it's
important to keep your eye glued on the
muscle and not so much focused on the
movement because if it's a very
depressed reflex all you might see is a
contraction of the muscle but that will
a C 5, 6 again for the biceps on out of
the triceps which you could do many ways
if he's relaxed this way I could just
choose to leave his arm in the position
it is and I'm actually getting a good
reflex in this fashion show I probably
wouldn't proceed further but I could
also suspend the arm like this instruct
the patient to lean on my hand as though
leaning on a on a railing and the
measure of the hand being relaxed is
that the forearm is loose and then once
again strike the triceps tendon and this
is a 6,7,8 reflex a higher level than the
biceps 5,6.
if people are a hyperreflexic
you can often elicit a finger flexion
reflex it's only significant if it's
present on one side and not on the other
the patient's hand is very relaxed
and it's supported by his thigh
I'm simply inserting my finger in there
and asking him to just relax and leave
his fingers the way they are I tap on my
fingers and you can see the brisk
movements of his fingers
this is a finger flexion reflex that significance
is only if it's absent on one side and
present on the other
we're going to do the brachioradialis reflex it's
important to tap on the tendon and not
the muscle and to look at the muscle for
contraction rather than looking for the
movement so even though there's a nice
brisk movement you see the muscle
contracting as well
I'm then going to do the biceps reflex I put my hand on the
biceps tendon and I tap on my thumb keep
my eyes glued on the muscle
both these reflexes the tricep the biceps and the brachioradialis are C 5,6
in the same position I can also do the triceps reflex as the patient is nicely relaxed
I'm going to strike over the triceps
tendon and look for the contraction of
the triceps muscle
and I see a contraction you might or might not see a
movement of the arm
the ankle reflex in a patient who is seated like this can be
a little tricky and if it's not a very
brisk reflex you might conclude that it's not there
I would make sure that the foot is loose put a little bit
of tension on the muscle but not too much
and then strike over the Achilles tendon
and I can both see a contraction
and see the resultant movement
this is S1 level this is a great example of how
this hammer gives you a great advantage
over a little tailor hammer
I'm now going to move up to the knee reflex and
again with the patient sitting like this
and very relaxed it's quite easy to hit
the patellar tendon and notice a nice
brisk contraction of the quadriceps
muscle again be sure to expose the
muscle you're looking at keep your eyes
glued on the muscle don't worry about
the movement especially the vastus medialis
which is the last thing to go
when you lose the knee reflex
the ankle reflex in a
bedridden patient there's a little more
tricky and there's a couple ways you can
do it but it's easy to conclude that the
reflex is not there when it actually is
and your technique impeded you from getting it
one way to do it is to simply make a bar with your two fingers across the the metatarsal heads and cock the foot up just a tad
keep your eyes on the muscle and in this case you can actually see a nice brisk contraction just by this
yet another way to do it is if the patient is mobile and has fairly loose joints you can outwardly rotate the hip flex the knee a tad
again put a little bit of tension on the tendon keep your eye glued on the muscle don't worry about the movement the muscle is what we want to see
and we see a very nice contraction this is again S1
yet another way which is useful in someone who doesn't relax very well is to take the foot you're examining
and cross the upper one third of the foot you're testing over the lower one third of the other foot
and the great beauty of this method is that if you get them positioned successfully
the patient cannot keep their foot caught it winds up being a great position because they are unable to contract their foot
and now I put a little bit of tension their eyes glued on the muscle
and we see a very nice contraction
this is the ankle reflex its S1
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