[Music] I'm now going to demonstrate the deep tendon
reflexes. And doing the reflexes: it's 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's Square Hammer. We give this to all our incoming interns. I think it has
a nice flex to it and is really a 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 C5-6 reflex. I'm also gonna do 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.
That level is C5-6 again for the biceps. And now to 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, so 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 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 hyper-reflexic, 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 biceps and the brachioradialis are C5-6. In the same position, I can also do the
triceps reflex. As a 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
put - 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 Taylor 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, it is to take the foot you're examining
and cross the upper 1/3 of the foot you're testing over the lower 1/3 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 taut. It winds up being a great position because they are unable to contract their
foot. And now I put a little bit of tension there, eyes glued on the muscle, and we see a very nice
contraction. This is the ankle reflex. It's S1. The preceding program is copyrighted
by the Board of Trustees of the Leland Stanford Jr University. Please
visit us at med.stanford.edu. [Music]