HOST: Dr. George Metzl
GUEST: Dr. John Kennedy
You are listening to ReachMD XM 157, the channel for medical
professionals. Welcome to the Clinician's Roundtable.
I am Sports Medicine Physician at Hospital for Special
Surgery in New York City. We are really pleased to be joined today by Dr. John
Kennedy, who works at the Hospital for Special Surgery. John is an orthopedic
surgeon and a specialist in foot and ankle problems. There was an article in
the New York Times about a year ago, looking at custom orthotics and custom
orthotics are in New York City many, many 100s of dollars. These are products,
which are used to correct the people’s foot into neutral and basically there is
a whole range of products from the off-the-shelf orthotics which are like $25,
maybe $30 to the custom orthotics which can range upwards of $500 and the
conclusion of the New York Times was as well as several studies looking at the
efficacy of custom orthotics versus over-the-counter orthotics, that the vast
majority of patients did not need custom orthotics, but that certainly is not
the case, that many patients, in fact, do get custom orthotics, so I wanted to
start the second half by asking John about the issue around custom orthotics
and what his thoughts were about that product, when are they necessary, are
they over-prescribed and what is your thought on how this industry has evolved.
It is interesting because we get <__01:12___> a lot.
In my business, we do prescribe a lot of orthotics, but many of these do not
necessarily need custom orthotics. There are some very good off-the-shelf
orthotics that will address the minor mechanical instabilities that the
patients have. For those who have larger mechanical instability or those who
need accommodation for a deformity in the foot, certainly custom orthotics are
good, but it really is a case per case. You cannot say or condemn one or the
other. It really is case per case. I think there was a time where they might
have been over prescribed, but I think it is up to the individual doctor to be
honest about it and say we cannot treat with something just as effective and
perhaps not as costly with an off-the-shelf orthotic.
There is a role, but it has to be combined with the other
things we talked about in terms of this proprioceptive training and mechanical
training. The idea of an orthotic is that it is a static stabilizer if you
like. In another words it tries to restore this tripod configuration which is
very stable, lets the first ray and the second ray as being the base of the
tripod and the heel being the apex and if the heel is in a varus position or
tilting to the inside. Of course, all the weight is transferred to the outside
of the ankle joint. So if you can use a lateral heel wedge and combine that
with an arch support, you certainly will give a static stabilizing effect to
the foot, but once you put that foot in a position where it is unstable such as
unstable ground or turf, then you need all the other dynamic stabilizers such
as the peroneal tendons to be in phase and those proprioceptive fibers to be
firing. So, it is one part of the jigsaw, but not the complete thing.
Fair enough. What about the issue of running shoes, both
you and I are deluged with runners or want to be runners who are trying to coax
their body towards the New York Marathon in some way or another. What about
your thought on the evolution of the running shoe from the first generation
Nike, which you may recall this one the kind of white with the red stripe and a
flat sole like a waffle sole and nothing to where you come to today, what is
your thought on the evolution of the running shoe as foot type in the way
somebody runs and we are talking about overuse injuries, but still on the topic
of ankle injuries in sports.
It is true. I think the whole industry, in fact, the
running shoe industry is developing the way we want to see and it is doing that
because we and they have collaborated, and that is the most important thing
that we collaborated with industry to show them and advise them what is needed
our there to prevent these overuse injuries and we had done that with a number
of the major running shoe companies. We actually have a lab as you know in the
Hospital for Special Surgery, at the running lab there where we can put lot of
these athletes through their paces and at the same time measure the forces
through their ankle, through their knee and through their hip and then use the various
different types of commercial running shoes to see how it affects them.
Everybody’s foot is a little bit different and just to pick something off the
shelf and hope that it will work for all of us is perhaps not realistic and I
think now what is happening with the industry that they are recognizing that
and they are building a combination for different types of feet. So it is
certainly moving in the right direction.
It has been remarkable to see and as you know here in New
York, a number of the different running stores now have treadmills and video
analysis in the stores, so they can video your foot when you run and see how
much you role and try and suggest a shoe for you. So I think it really has
come a long way.
It is a common sense approach. Make sure that the person
who is advising you knows enough and make sure that it feels good. Here one of
the things that many of the stores here they do. They actually get you to go
outside and run up and down the street and that is really what you need to do.
Does it feel good or is it over-pronating or is it over-supinating; and so you
really need to rather than just take it out of the box, put it on and <___05:16__>
run up and down. If they have a treadmill all the better and there should be
an orthotist or there should be pedorthotist who can look and really advise you
professionally rather than shoe salesman say that's the right one.
There was an old country music song here which was called
“Mamas don’t let your babies grow up to be cowboys”, which was basically
discouraging parents to raising cowboys as kids and so my question to you John
is “Mamas don’t let your babies grow up to be marathon runners”, what is your
thought on that, healthy or not?
It is a great thing. It is honestly the whole running
industry is tremendous for people and people’s health and so forth, but there
is a point of course when you can overdo like anything in life, and I think
part of the thing that we see is the overuse injuries. Clever sensible
training that is well modulated and it is fine. I do not think we were
designed necessarily to be running marathons all the time and when you see
people doing 8-9 marathons a year, they are at least athletes. So I think that
you know, if you are doing that much mileage whether it is marathon or
triathlon whatever it is, ultimately you are going to have injuries and the
most important thing is to recognize them when they occur and to deal with them
and just hope that they don’t go away because they will not and you do need
professional help at that point.
If you are just joining us. You are listening to
Clinician’s Roundtable on ReachMD XM-157, I am your host Dr. George Metzl and
our guest today is Dr. John Kennedy, orthopedic surgeon and foot and ankle
specialist from Hospital for Special Surgery.
John, we talked in the first half about ankle injuries and
touched on the imaging of ankle injuries, meaning how MRI has really changed
the equation allowing us to look not only at the ankle itself, but look inside
the bone, look for edema, look for cartilage wear patterns and something which
I know you are interested in is the issue of osteochondral injuries in the
ankle and in the talus predominantly. So why don’t you give us a little
scenario of how a patient would come into your office with an osteochondral
injury to the talus or to the ankle and how would you go about kind of helping
them figure out that may be what they have and then we can talk about how we
take care of those.
Typically, an osteochondral injury can be either from a
traumatic type and/or the de novo type and the de novo type of osteochondral
injury may be from a bone cyst or some form of vascular malformation and that
generally occurs in the bone first; and if you think of the bone being the
scaffold in which the cartilage lies, ultimately with repetitive loading either
from an inversion injury or from even marathon running can cause the cartilage
simply to fall into that cyst. That is the de novo type of osteochondral
lesion. The traumatic type is generally caused by inversion injuries or
repetitive inversion injuries and in those cases, the cartilage is injured
first with bone bruising and bone cavitation as a secondary result of that. So
the standard now really for in terms of diagnosing that, I would say the
careful clinical history and evaluation, but it really is down to modern
imaging modalities such as MRI and CT where you can really get a good sense of
what is going on with the cartilage and how much bone is involved. In those
cases where there is a traumatic injury, just to the cartilage itself, those
are amenable to arthroscopic debridement and microdrilling. When you
microdrill, you do not get normal cartilage; you get fiber cartilage, but if
the defect is small; in another words, if it is less than 6 mm, that fiber
cartilage appears to be robust enough that it would not predispose you to
further degeneration and arthritis. In the cases where it is larger than that
or when there is a cavitation of the bone or there is a cyst in the bone, those
are the cases that we have to consider doing osteochondral autograft
transplants. Now we get those in general from the ipsilateral knee through a small
incision, a small arthrotomy and we take a little chew which is like the old
apple core we used to take out the core of an apple. It is the same device
essentially it is about 8 mm core. We take that plug which is both bone and
cartilage and we put that into the area of the defect within the talus; and
those few patients do well and in this case, it is replacing cartilage with
cartilage and the long-term studies of that are very encouraging; and I think
that is really where we are going. We are doing a lot of work here at Hospital
for Special Surgery looking at various types of cartilage replacements, looking
at triggers which are genetic triggers using heat shock proteins to try and
stimulate native cartilage to grow. The big problem is when we put these
pastes in or these matrices into the area, they tend to work well in the lab,
but when you put them actually into a real-life talus it is moving, of course
they get washed away, and so the mechanical factor is something that we still
have yet to work on. So, it is a very exciting area to be working in and
particularly because as I said with one of the imaging modalities we are seeing
that more and more and more patients do have these chondral injuries and in a
recent study, it was interesting to see that about 60% of patients who have an
ankle inversion injury had a chondral injury of some sorts and that is an
enormous number and it is only diagnosed, except in old age when we got an
x-ray, of course, we did not see this; and so when the patients had this
chronic ankle pain afterwards, we just said suck it up and off you go. Now, we
are recognizing that there is something going on in there and it is relatively
simple; if you catch it early, it is a relatively simple procedure to
microdrill it with a very, very predictable outcome.
Lets say you are working in a primary care clinic, you do
not have MRI right downstairs like we do at Hospital for Special Surgery, but
you are out some place that is not accessible to you, how are you going to identify
the person who may have a osteochondral or chondral injury versus the patient
that just has rolled their ankle. How will that be different clinically.
Well generally, it is more of a chronic type pain. The
ankle instability often times is not necessarily painful. It is inconvenient
and it is painful at the time that they roll it, but it isn't a constant dull ache
that they have. The osteochondral injury will be that typical dull ache,
generally precipitated by running or repetitive loading. That is just on the
history aspect of things. Often times, of course they will have had a history
of repetitive inversion injuries. On the examination, if you put the talus
into full plantar flexion, you are actually bringing the most commonly injured
area, which is in fact the central portion of the talar dome both centromedial
and centrolateral, you bring that into an area where you can actually palpate
and palpating in there, will actually elicit pain. It is an interesting exam
because we do not often do it, but if we do it, just press into those lateral
and medial aspects of the central dome and that will elicit pain. So that is
just on the clinical exam. Now of course, if you have access to an x-ray on
those cases, which have cystic changes within the bone, you will see that on
x-ray and if you look for it again both in centrolateral and centromedial.
Traditional view <__12:01___> anterolateral, but it is not in terms of
these traumatic. Again a study we have done here had shown that the vast
majority of these are central lesions and we think about the anatomy that is
the closest or approximating area where the tibial plafond hits off the talus
in an inversion plantar flexion injury.
You have talked about both the acute traumatic and the
overuse osteochondral injury, which is more common?
The traumatic, much more common. Yeah, we see that and I
think we are going to be seeing that more and more with more imaging modalities
we do, it will be diagnosed more readily.
Well terrific John, thanks so much for joining us today. You
have been a terrific and very informative guest.
Many thanks for having me.
I am Dr. Jordan Metzl, you have been listening to the
Clinician's Roundtable on ReachMD XM 157, the channel for medical
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