VASS Results

VASS Results

Charles H. Pritham

10/26/2002

Thank you to everybody that took the time to respond to my inquiry. In
general I think it is fair to say that the results are mixed. For the
benefit of the curious, I include the gist of the comments below.

C. Pritham

We have tried the Harmony system multiple times with mixed results. The
concept is great but the product does not work very reliably. Maintenance,
continued use of suspension sleeves and weight are the client reported
problems. I am waiting for the next version before recommending it again.


I refuse to use this system since it voids the warranty on the foot.


I have tried VASS system on one patient that has been using vacuum
suspension for the last 6 year. His comments were after couple of month
The idée is not too bad but it is too heavy and the suspension doesn't
work properly, and then he went back on his old prosthesis. This is
also my believe, that it is a good idée but needs to be more developed.
It could enhance the blood circulation for those patients that have
problem with that and at the same time be a problem on patients that
have to deal daily with volume changes. The weight of the device is also a
problem and the system needs perfect suspension sleeve to work well and I
find it still difficult to find a sleeve with that requirement... I believe
that for a healthy active user the volume will be come more stable in a
system like this. The system is exciting and interesting and I would
recommend you to try it just to build your on ideas on it.
Good luck
(The gentleman quoted above is Swedish. Before you criticize his English,
translate his comments into Swedish.)


We fit two different amputees with the VASS system. I regret to inform you
that we were less than pleased with the results. One of the systems
incorporated joints and thigh lacer so we had this manufactured by TEC.
Inadequate space was provided between the inner and outer sockets which
resulted in the suspension sleeve being pinched and torn. TEC was unwilling
to correct the problem. We remanufacutured the outer socket (in our
facility) so the client could use the prosthesis. Unfortunately, the
maintenance was very high on this device. The locking mechanism had to be
replaced twice- due to normal wear and tear. The client's comment: I like
it when it works, but it just doesn't work very often. It is really heavy.
About three months ago, we redid the socket (no charge) and provided him
with a locking pin (joints and lacer too). His mom cal! led me recently and
stated that it was working well.
The second client also liked the socket initially, but felt that maintenance
was too high on it. He went back to his old leg. TEC will try and convince
you that only you are experiencing these problems, but I won't be
surprised if you recieve a few negative comments


I've fitted this system on two bilaterals and two unilaterals. While it is
not yet trouble free I am very impressed with the degree of comfort and
quality of suspension it provides. I've been using Dermo cushion liners and
a variety of sleeves but so far the Alps EZ sleeve has worked best.


I have just received
my certification in VASS. My experience with the system is therefore
somewhat limited however, the science is well done. I believe Mr. Casper is
really on to something here. I would recommend to all practitioners to
examine the information and make there own decisions as to the
appropriateness of this modality for their patients.

It may take some time for the mechanics to be perfected yet again the ISO
testing protocols used to test Harmony were extreme, three million cycles
@3/second with three hundred lbs. is impressive.


Good, but..........Complex, lots of things to go wrong. The pumps have had
several failures but TEC stands behind them completely. Many come back
visits to correct small problems so the patients needs to be willing to
travel and be able to follow instructions to the letter. I have had good
results with this system on problematic residual limbs. I understand that
and L-code for this system in to come very soon.