This is Brent of the Brookbush Institute, and in this video we're going to do femoral
nerve neurodynamic testing. I'm going to have my friend Yvette come out, she's
going to help me demonstrate. Now keep in mind if I'm doing these femoral nerve
neurodynamic tests, Yvette's already given me reason to think that the
femoral nerve may be involved in our subjective examination. So think about
neurogenic symptoms things like tingling, numbness that that sharp shooting pain
that happens when nerves get really inflamed, like you some of you who
have had sciatica you think in that direction.
Think about paresthesia, the pins and needles and generally people with
femoral nerve issues have had lumbar pathology in their history, or currently
have lumbar pathology. Keep that stuff in mind because this test actually looks
exactly like Ely's test, if any of you know Ely's test for rectus femoris
extensibility, these tests are identical with one big difference. As I'm doing the
pro knee bend or naklas femoral nerve test, what I'm looking for now is,
Yvette how does this feel? (Fine.) I'm looking for her concordance symptoms that were
perhaps more neurogenic in description. So does this bring on any of that
tingling in your thigh you were talking about? No. Does this bring on any back
pain? No. So you have no lumbar pain, no tingling. So we can get a
little bit more provocative by adding a little extension now. So now
we'll go with with as much knee bend as I can get, I'm still going to use this hand
to stabilize her pelvis because I don't want to push her into lumbar extension. I
don't want this to become a lumbar extension test. I still want to test
just lengthening of the femoral nerve. So now I'm going to do this. Hey how
does that feel? Still fine. So this would be a very negative test obviously, but
notice while I was going through this I wasn't just looking at knee
flexion restriction. I wasn't just looking at hip extension restriction, I'm
not just testing the rectus femoris. I'm trying to see if I increase tension
in the femoral nerve by stretching it, do I bring on
concordant signs related to her pathology, the symptoms she was
complaining of as I go through these motions. Now there's a couple other
things we can think about as we do this test that was the basic test, I want you
to get good at that test understand that test. That test you should probably
have memorized, but we can start differentiating a little bit here. So if
I just for example did both legs, compared sides and happen to notice that
her opposite leg, let's say she came in with with left-sided lower-back pain, and
her right leg brought on left lower-back symptoms that's the cross femoral nerve
test, and it usually indicates more discogenic issues, maybe an HNP. Okay so
that's very similar to if you saw the straight leg raise test or the slump
test. The same thing there, if the opposite leg brings on symptoms you know
you probably have some discs stuff going on, and you can think in
your head from an Anatomy perspective you probably have to have a pretty
significant disc issue that stretching the opposite side nerve affects this
enough to bring on pain on the opposite side of the back. Now we can do a little
differentiation too, if you wanted to get a little fancier and start
thinking about well what nerve roots are involved and potentially how could I
treat out some of this neural restriction, you can make this a
lateral femoral cutaneous nerve test by doing the same motions but adding a
little adduction at the hip. So now I'm bringing her knee towards her other knee
so that might give me a little indication of what nerve roots involved,
or maybe I want to do some different release techniques to try to help
increase mobility in that tract. The other thing we can do is a saphenous
nerve test, this is a little different but same position, where I'm going to go
into dorsiflexion and e-version at the ankle, total extension of the knee
and then I'm going to externally rotate at the hip and adduct, alright so that's a
saphenous nerve test.
So we did the naklas pro knee bend, we talked about the opposite
side, so that's the cross femoral nerve stretch being a sign of discogenic
issues, we talked about sensitizing this a little bit for the lateral
femoral cutaneous and saphenous nerves, and you can get fancy with that. The
other thing that you probably want to be aware of is you can do this same test,
sometimes called the femoral traction, femoral nerve traction test in
side lying. So I'm going to have a Yvette go ahead and lie on her side, face
the camera. This comes in handy and I'll tell you why some people, especially
with lumbar pathology don't tolerate lying on their belly like that. You
won't be able to get the test done. They'll lie down they'll be in pain,
you'll start flaring them up and then that's just uncomfortable for both
of you. If I bend this knee to keep her nice and stable I can use this
hand to stabilize her pelvis.
I can then bring this leg back and just twist right around this way. So
now I'm bringing her into hip extension and knee flexion, and I'm
following the same path of logic. As I increase tension I'm looking at Yvette's
face, I'm asking her hey does this bring on any of those symptoms that you were
talking about? No, good. Some of you are already thinking much like
with the prone test, wow that looks a little like Ober's test, it does. So
think about your use cases. If I was just doing Ober's tests chances are I'm just
looking for mobility issues, right Ober's test is a TFL extensibility test. If I'm
doing this for the femoral nerve, again I'm looking for those neurogenic signs.
Does this bring on tingling or burning in her quadriceps, does this
bring on her lower-back pain, and again we could even do this on both
sides and do that crossed femoral nerve thing. So there you have it, you have
the prone knee bend, you have the sideline, you have the
crossed thing which is an HNP sign, and of course you can start
differentiating a little bit with the femoral lateral cutaneous adding
adduction, and then you can do the saphenous nerve and prone. The big things
to keep in mind is you stretch the femoral nerve with hip extension and
knee flexion, and this is a great test for you to start wrapping your head
around this idea of predictive values and special tests. So if you use this
test with individuals who have lumbar pathology and the right symptoms that
they're complaining about, they're great tests. If you just use
these on everybody who walks into your clinic regardless of what symptoms
they're complaining about then I'm telling you right now these tests are
going lose some of their sensitivity and specificity, because your
predictive values go way down when there's no neurogenic signs to latch on
to. For those of you who are students again, this is one of those
tests where I would put it on your list of things you want to see in clinic,
that's what your clinical affiliations are for. You are going to do this to each
other in class and you're not going to feel anything. It's going to feel exactly like
the Ely's tests or exactly like the Obers tests, and that first person you
get who has femoral nerve stuff, if you're this aggressive with them I can
tell you right now you're going to send them out the door as fast as you
possibly can, and then number two of course it is going to feel very
different on a nerve patient, someone with nerve involvement that is
going to feel just muscular tightness. Those things are not quite the same. If you
had any questions on those things. please
go ahead and leave them in the comments box below. I hope you guys enjoyed this
video.