Re: AK water ski prosthesis

Garth Knapp

Description

Title:

Re: AK water ski prosthesis

Creator:

Garth Knapp

Date:

11/8/2012

Text:

Dear List,
Below are the responses to my earlier post regarding a TF water ski
prosthesis. I appreciate the responses and suggestions. We plan to use a
seal-in liner with passive (expulsion valve) suction for simplicity
initially, in conjunction with the distal compression straps on the
bare-foot water ski wetsuit as auxilliary suspension.
He plans to ski with his Lt (prosthetic) leg in the forward position. We
plan to use his XT9 knee and an old Genesis II foot with the anterior and
posterior bumpers removed.
Garth Knapp, LCPO
Olympia, WA




It has been my experience that the wet suit is a excellent secondary
suspension. Adding a couple of reinforcing straps and a KISS knee sleeve
strap would be helpful.

What about skiing without the prosthesis. Most amputee skiers of high level
use a single modified ski with the boot moved appropriately forward or back.
Jim Rogers, CPO


I'm not sure if you are designing a ski only prosthesis? If so, for the
sake of simplicity I would just do a locking liner (maybe even a Kiss
system to eliminate potential lock corrosion problems). If it is going to
be an every day prosthesis (or if he has a long residual limb) I would
fit him with a seal-in liner and add a summit lock strap to it for
auxiliary suspension. He could even remove the summit lock when he didn't
need it.

Todd Norton, LP, CP

If you are also afraid of him losing the liner (which unless he has a very
short limb, I can't imagine) a Tes belt is cheap, comfortable, water proof
and durable enough.

Garth,

You might look at the double wall sockets available from Evolution
industries. Suspension is very good. They also sell the aura/ echo socks
which hold elevated vacuum perhaps better than a seal in liner.

Zach Harvey, CPO


Russ Burton <Email Address Redacted>
Nov 1 (6 days ago)

 to me
In 43 years I've known many AK amputees who water skied. I've never known
one who used a prosthesis. Most persons that are accomplished water ski
nuts prefer to slalom ski anyway. Even if he is a beginner, he will have
better luck without a prosthesis. Another consideration is that a
prosthesis can be an anchor in the water. Be careful what you advise.

Garth,

What is his sport? Slalom?

Is this his front or back leg on the ski? Will he change dominant leg ?

Binding set up on ski?

You may consider going with out the knee unit as stance doesnt require much
knee bend.

I am into skiing but havent made a leg for a skier would be interested in
outcome.


On Fri, Nov 2, 2012 at 4:09 PM, Chelsea Luttrall < <Email Address Redacted> > wrote:
For my own education, what are thigh compression straps? Can u post your
responses?
On Fri, Nov 2, 2012 at 4:32 PM, Garth Knapp < <Email Address Redacted> > wrote:

> These are just circumferential straps around the thigh which help hold the
> leg of the wetsuit down, and will also help hold the socket on. A wetsuit
> made for barefoot waterskiing is thick, padded, and reinforced and will
> provide good auxiliary suspension.
> I will post responses-
> Garth
>
>

I assume this is not your patient but you never know:
<URL Redacted>

The most single important stance in slalom skiing is a stacked stance, it
is dorsiflexion at ankle, to move the forward knee and body up into a
position where the body is centralized on the ski in order to be able to
cut through the wakes in a strong position:

Lots of video and pictures available as slalom skiers are about the single
most technical, picky group of sports enthusiasts that I have ever
encountered. We measure of ski fins to the thousandths of an inch, and
debate all sorts of stuff. Probably as much motion analysis occurs in
slalom skiing as does at RIC.

Anyhow, I suspect he will want to be able to have some rotation in the
system so that he can move his center of mass off the side of the ski to
both sides naturally.

Have him bring in a ski with the fin removed, and a ski handle so you can
tie his handle off somewhere in your facility and he can feel stance on the
ski.



>
>
>>
>>
>> On Oct 30, 2012, at 2:46 PM, Garth Knapp < <Email Address Redacted> > wrote:
>>
>> > Hello List,
>> >
>> > I haven't been able to find any specific information regarding
>> prosthetic
>> > suspension for an AK when water skiing. I am hoping someone has had
>> direct
>> > experience with this.
>> > I have a patient with a professional ski boat and an XT-9 knee who
>> wants to
>> > get back into water skiing. His primary concern is suspension.
>> > I'm thinking about a seal-in liner with a Limb Logic vacuum system, in
>> > conjunction with the thigh compression straps around the outside of his
>> > custom wetsuit. We would like to avoid using a waist belt as auxiliary
>> > suspension.
>> > Flotation for the prosthesis would be added in case of separation.
>> > Thank you for your input.
>> >
>> > Garth Knapp, LPO, CPO
>> > Olympia, WA
>> >
>>
>
>

                          

Citation

Garth Knapp, “Re: AK water ski prosthesis,” Digital Resource Foundation for Orthotics and Prosthetics, accessed November 25, 2024, https://library.drfop.org/items/show/234096.