Responses Capp Terminal Failures

Bill Baughn

Description

Title:

Responses Capp Terminal Failures

Creator:

Bill Baughn

Date:

5/17/1999

Text:

Below is my original query to OANDP-L followed by the responses I received
and finally a response to your advice from the father involved. Many
thanks to all who responded. Due to your interest this problem appears to
be solved.

Bill Baughn


---------------------------- Original Message ----------------------------

From: Bill Baughn < <Email Address Redacted> >
Subject: Capp Terminal Failures

The father of a twelve-year-old recent right below elbow amputee writes on
the Child Amputee list that his son's Capp terminal device suffers a cord
failure about once every three weeks. His prosthetist has no experience
with the Capp and has no idea what might be the cause. We will appreciate
any suggestions.

Bill Baughn

------------------------------------ Replies
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Dear Bill:

Please check with the father or the son as to where exactly the cord is
failing. If the cord fails at the attachment point in the actual terminal
device chances are that the prosthetist is using the incorrect knot. Contact
TRS for a diagram of the knot and then put one drop of super glue on the
knot. If the cord fails at the end of the housing chances are that there is a
sharp edge on the housing. A Teflon insert and a farrell will solve this
problem. Good luck and do not hesitate to contact me should those solution be
inadequate.

Sincerely,

John M. Miguelez, CP

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Mr. Baughn:

the problem could be in many places and it would be helpful to know where
it is breaking.

the ones not described well in the instructions include:

1. if the cable exits the TD and is not directly connected to the housing,
the exit should be lined with the threaded plastic insert so the Dacron
cord does not get sawed by the threads of the exit holes.

2. if the heavy duty housing is directly screwed into the exit holes, then
it must be lined with Teflon to reduce the wear on the Dacron. the Teflon
should go into the CAPP TD far enough to keep the cable from rubbing on
the housing and be long enough so the same is prevented at the opposite
end. a custom soldering tip (which i believe Bob Radocy of TRS is
distributing. i haven't tried this one as i have some custom machined
ones) is needed to reflect the ends of the Teflon so it is like rolling up
your shirt sleeve. this prevents the Teflon from migrating in the housing
and provides a nice strain relief for the cable rubbing on the housing.

if this is not where it is breaking, let me know and i will try to
offer some suggestions.

Ramona M. Okumura, CP

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----------------

======== Fwd by: Robert Carlil ========
You might start by changing the wire/string to a thicker one,then check to
make sure that there are no sharp edges and that your wire or string and
move freely.This seems to be some of the things we run into with ours.

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Bill,
    Try installing a full length nylon cable lining from the entrance point of
the TD housing to the exit point to where it attaches to the hole of the TD.
Jeff

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---------------------------------

12 years old sounds very old for the CAPP terminal device I am aware of- it
looks like a lobster claw and was designed for toddlers. Are you sure you
have the facts right? If a 12 year old is using this, the thin braided nylon
cord would not hold up very long at all. Mike Quigley,CPO

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---------------------------------

I don't use cap because I dont think it
is a good terminal device. This has has
nothing to do with the failure your talking
about. Look to TRS and spectra.

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-------------------------------

Dear Bill:

I am responding to your email of May 4 regarding the 12 year old boy
with a CAPP terminal device. Hosmer Dorrance Corporation is the
manufacture of the CAPP device. We suggest that the parents send the
unit in for examination. There may be a simple answer to the breakage,
like the wrong replacement line used or a problem with the spring. The
child's usage and setup may play a factor as well. What activity level
is this child? Would the child be accepting to change to another style
terminal device?

I look forward to hearing more about this little boy.

Sincerely,

Jackie Bradford
Hosmer Dorrance Corporation
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Bill--
I have a fair amount of experience with the CAPP TD--both the child and
adult versions. I have found that replacing the standard 150 lb test braided
Dacron trolling line with braided Spectra™ fiber line results in a much
greater life span. The Spectra™ fiber is only slightly larger in diameter
than the Dacron line. It can be easily obtained through Bob Radocy at
Therapeutic Recreation Systems, Inc. (TRS) in Boulder, CO.

It is best to also use a Teflon-lined cable housing with either the Spectra™
fiber or the Dacron trolling line.

Hope this helps out.
J. Thomas Andrew, CP
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--------------------------------

Mr. Baughn,

First, I would like to thank you for the information you provided to me
regarding the Capp prosthesis which Alex is using. I provided the
prosthetist with all of the suggestions received. The prosthesis has been
modified.

Where the threads are in the wrist unit, a Teflon insert was added, and the
cord was replaced with a spectron line. Now it is wait and see what happens
next.

Regarding blaming Alex, I did not know whether or not he was abusing the
prosthesis. Sometimes I have seen Alex pulling on the cable on his harness,
with his hand just to see the terminal function. I thought that maybe this
had something to do with the constant breaking of the cord. After all of the
responses I received, I can see that modifications needed to be made. Thanks
again.

Sincerely,

Brett Patton

Citation

Bill Baughn, “Responses Capp Terminal Failures,” Digital Resource Foundation for Orthotics and Prosthetics, accessed November 27, 2024, https://library.drfop.org/items/show/211867.