Replies - Townsend Polio-style knee brace

Replies - Townsend Polio-style knee brace

Mark Raabe

5/13/2003

-----Original Message-----
From: Mark Raabe [mailto:<Email Address Redacted>]
<mailto:[mailto:<Email Address Redacted>]>
Sent: Tuesday, 6 May 2003 10:17 PM
To: OandP-list message
Subject: Townsend Polio-style knee brace

Fellow colleagues,
Have a pt. with post-polio syndrome, major concern is hyperextension (approx
20°), at the knee. Trialled CAMP Hyperextension KO with no success -
excessive pressure over distal tibial crest. History of several custom made
KOs from other orthotic centers, all with the same result.
Question : has anyone out there used either the Townsend full shell or
premier polio-style KOs for successful hyperextension control?? Hesitant to
commit to custom made devise that may prove no better than previous braces.
Will list responses...
Mark Raabe, CPO-AOPA
OrthoSynergy Pty Ltd
P: 612 9526 8066
F: 612 9526 2507
E: <Email Address Redacted> <mailto:<Email Address Redacted>>

Replies separated by line...

I have fit one paient with this type of orthosis. Functionally, it has
worked well for controlling the patient's knee hyperextension. HOwever, I
have had a number of problems with the hook portion of the hyperextension
control strap coming off the shell of the brace as well as a problem with
one of the straps coming loose from the rivet that holds it to the shell.
The other drawback with this brace is that it is extremely heavy.

Have you considered the Ambroise UTX brace, designed and manufactured by Dr.
Nils Van Leerdam, in Holland. They make a brace which will allow free knee
flexion/extension in swing whilst locked at full extension during stance. It
will also prevent hyperextension and yet only weighs a couple of pounds. See
the Becker Orthopaedic web site for details. I've seen a few here in the UK
and they're great.

Have you considered an AFO? Possibly more plastic shell at calf will help
vs KO.

Townsend brace is a heavy ,bulky brace that doesn't do much more than an
off-the-shelf version with a check strap in the back.If hyperextention is
your problem why not simplify things and use a hinged swedish knee cage.This
can be custom made too,if your patient has one of those knock-knee valgus
deformities that plague the polio patients

I think you will really need to go to a KAFO to get comfort. Check the
ankle muscle strengths and add dorsi stop or dorsi assist if needed. You
might also find an equinus contracture that is pushing the knee back. Often
fused surgically when they were kids - to provide knee stability. If this
is found - you will need to add a heel lift to accommodate it. If there are
no real problems at the ankle - you can always just use a heel cup to
suspend your KO/ KAFO. Good luck -

Save yourself a lot of time and grief. The gentleman needs a KAFO, not a
KO. Townsend is a good design--so is Flextech. Use and anterior thigh
shell. Flextech is a little heavier than Townsend but also a little less
expensive.

Have you considered any shoe adjustments in order to shift the GRF and
reduce the forces required to restrict the hyperextension. I'm presuming
patient has weak quadriceps given the hyperextension and that the underlying
cause of hyperextension is stability? You may need to make a KAFO so that
the AFO can assist in applying the forces you require i.e. preventing the
leg from moving into hyperextension.

I have on several occasions used the Townsend shell design with success.
They will customize the fab for you. I tend to ask for extra padding in
this population wherever I feel necessary. The only problem I had was
distal migration on a couple with significant atrophy of the calf. Overcame
eventually with minor mods to the brace. DO NOT USE THE PREMIERE DESIGN!!!
I recommended Townsend to my new boss for basically the same patient you are
talking about. They recommended the Premiere, so I said to try it. I
thought it would probably be of the same quality. The brace weighed about 4
pounds! This was a petite lady. My KAFO's don't weigh near that much. It
also wasn't even close to fitting her. I think Townsend is having problems
in their fab area. I have heard of several similar problems. When
discussed with Townsend they were less than sympathetic, almost insulted. I
have been practicing 20 years and am a CO who does a great deal of my own
fab, so,believe me, I know. Stick with the old shell design polio brace and
I think it will work for you. Hopefully it fits, if not they'll make it
over, though they will charge you for shipping. Feel free to call with
questions.

I just put a man in Bilateral Premier Full Post Calf Cuff KOs with excellent
success and control. Interesting thing about this case was that, if his
legs are allowed to hyperextend, his lack of bony locks and muscle tone will
allow his knee to hyperextend to approx. 85%. OUCH!

You will not have success controlling the knee if it is severe if you ignore
the foot. How much is the foot plantarflexing during stance? We have had a
great deal of success with Townsend polio braces but I do not waste my time
with KO's for hyperextension. Good luck.

I assume that you have tried the following, though I place them here in case
you haven't. Hinged Swedish knee cage (off the shelf) Custom KO with heel
cup extension to prevent migration. Cast in ~5 degrees of hyperextension
with posterior offset joints. I don't know why either of these would not
work. Maybe there's more to the problem.
Check his ankle position during stance, he probably has a plantar flexion
contracture. Associated with weak hamstrings, the ground reaction force that
is generated hyperextends the knee. You may wish to try an AFO to begin
with, if this is not enough you can add posterior set knee joints and
anterior thigh shell, ensure knee joints are set in slight knee flexion. The
combination of AFO attached to thigh shell set in slight flexion should
prevent hyper extension.

I think your patient will have to accept the fact that it is time to use a
KAFO, but it might be a great time to convert this patient to one of the
stance control knee joints. Take a look at the Horton web site. The man,
Paul, featured is a polio victim.

I've fit a number of post polio patients with the Townsend Primier KAFO.
I've had extremely good success with this system. The patients have
been very pleased with the control provided. I've also converted a
number of existing KAFO wearers with post polio syndrome to the
Townsend. On a few occasions, I've had to modify the orthosis by making
a wider 1/8 polyethylene calf band to better distribute the pressure in
controlling the hyperextension. I merely remove the padding in the KAFO
and replace it with plastic lined with 1/8 aliplast, about 60-75 mm
wide.

have you ever try the TKS - knee brace (Tree-Way-Stabilizer) from Teufel
(Germany)? This orthosis was developed by Prof. Lehneis (New York
University) especially to avoid hyperextension of the knee joint. The
TKS - knee brace has a very good patient-compliance due to the well done
anatomical shape. Simply have a look on our web side
www.teufel-orthopaedie.com .

Sorry to reply late. In my experience u can only control g.recurvatum by
giving a custom made KAFO i.e. KO side bars have to be attached with
shoe or heel insert.