locking mechanisms and hip flexion contractures

locking mechanisms and hip flexion contractures

Kristin

8/9/1999

Dear List Members,
   I was surprised to get so many responses. Even though most returns
were similar i thought i'd share them all with you anyway. Thanks to all
who took the time to reply. Kristin Bradley
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I make a strap about 20 inches long, attached to a ring brazed to the
screw that fits in the end of the liner. A slot is made in the end of
the socket through which the strap goes, then the strap goes proximal to

a chafe and velcros down to itself. This eliminates the extra length of

a lock, helps with distal traction and is easily adjusted. I make a
small tongue under the slot and a slot in the foam cover sleeve so the
strap comes out easily with a light push. This appears to be a common
practice;
I have seen several like it in other parts of the country.
Lane Ferrin CP
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Kristin,
I recently fitted a 53 yo male bilateral transfemoral patient w/
endoskeletal TFB and frame, 3S suspension polycentric friction knees and
Springlite feet. The problems that I've had using locking units besides
the trouble with pin alignment are rotational problems. This patient was
just fitted with Velcro straps attached to the locking liner with a pin
adapter attachment and super glue. Holes were placed medially and
laterally at the distal end of the socket and chafe loops at the top.
This helped also in donning the prosthesis by the patient pulling
himself into the prosthesis. I had to reinforce the frame with extra
fiberglass to keep it from folding distally when the chafe loops were
pulled on. It didn't totally prevent rotation but the ease in donning
the prosthesis was truly appreciated by the patient.
Good luck, M. Britt Spears CPO
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Dear Kristin,
We have some long TF and Knee Disartic amputees who use a silicon liner
with no distal attachment, and rely on suction for suspension. Would
this be a suitable alternative ?
Stephen Hockey,Technical Officer, La Trobe University
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This is a common problem and I have done the same thing that you have
described.
I would like to see a coupler (attachment device) that would allow you
to put
the socket in the appropriate amount of flexion and anterior
translation, and
then to be able to adjust it if the pt works out their flexion
contracture.
I look forward to reading other responses.
Mark Benveniste CP
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In cases like you describe I tend to use a lanyard (velcro strap) rather

than the locking mechanism both for cosmetic reasons and for ease of
donning.
Ted A. Trower C.P.O.
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Dear Kristin,
We have been working on a cable lanyard method with uses a tapped hole
in
the end of the plunger to pull the residuum in the socket. The cable is
twisted and then detached. If you are interested I could get one to you.

Presently it only works with the Fillauer shuttle system.
Gerry Stark,CP
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Have you considered using a laniard type of attachment for your silicone

liner on your AKs'. It is lower profile, and may give you more options
for
alignment placement. The patient doesn't have to be so acurate in aim to
line
it up on donnig either. Good luck -
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Kristin:
Instead of a pin you could attach a strap that would pass through a slot
to
the outer surface of the prosthesis where it would attach to a mechanism

(Lanier) or Velcro. Ossur of Iceland wrote this up once for the JPO.
You
should be able to access the text online at www.oandp.com/academy/jpo.
Good luck.
Bob Brown, Sr. CPO, FAAOP
Immediate Past Pres AAOP
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I have done the same, but I don't know of a cosmetic solution. On one
pt.
with a 45 degree contracture I used a hip flexion unit from otto bock.
It
allowed the pt. to sit comfortably, (with leg flat on chair) but it
required
a fair amount of coordination to operate. Hope this helps.
Todd Norton, CP
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Hi Kristin,
We have fit several AK's with 3s type liners. I would recommend using a

lanyard for the application you present. I recently fitted a 98 yr. old
male
with a slight hip contracture and a very long AK successfully with this
approach. We simply attached a dacron strap with a low profile bolt to
the
pin site and ran it through a hole centered as a loking mechanism would
be.
We placed a chafe and loop on the anterior proximal aspect of socket.
The
patient inserts the strap, pulls it through the loop and reflects it
onto
itself where Velcro secures it to itself. Then you can use any socket
adapter placed in the appropriate alignment for a proper TKA.
Good Luck,
Eddie
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hello,
you could try using a strap type setup that is threaded onto the bottom
of the silicone liner instead of limiting yourself with alignment
capabilities.
good luck
    KC RTP
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Kristin,
I have been practicing for 23 years. There is no getting around this.
First
the silicone sleeve is excellent if donning is not a problem. I have no

problem with pin attachment. You must have the correct flexion in
socket,
DON'T deviate. You cannot use the distal, one lamination pyramid system.
You
must have the attachment (socket to knee) back in the correct alignment
(correct TKA). You will end up with a banana shape socket, but you
cannot
deviate form our theoretical alignments. When you have a bad hip flexion

contracture, nothing is cosmetic. You are going for comfort and safe
function.
Hope this helps
Jake R. Wood C.P.
O&P Associates Inc., President
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With regards to your question on ak with flex cont.-
You could use an iceross lanyard system instead of a pin system. This
will shorten overall length and improve cosmesis. The socket adapter
must be laminated or positioned not in tthe long axis, but with
respect to the proper weight line.
hope this helps
andy d'Entremont C.P. (c)
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Dear Kristin:
Your problem is not unique. Two possible solotions that have worked for
us
are to eliminate the use of the pin system and use either a lanyard
system
like the one available from Ossur or use a simple velcro strap
arrangement
that we have come to appreciate.
 What we do is make a dacron backed velcro strap and attach it to the
end of
the silicone insert. We create a channel for this strap to slide through
by
using a dummy of pelite or clay over the distal end of the cast. We
usually
direct the strap laterally and use a simple d-ring retainer somewhere on
the
lateral side of the outer socket. This ensures that the patient can get
into
the socket securely, even when seated!
Good Luck.
Jim Rogers, CPO
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