Replies:Question on ankle motion to amputees

Replies:Question on ankle motion to amputees

Here is the original post:

I suspect this is a personal preference, but I would like to see if there is
a concensus among amputees as to any difference in the stability felt from
the floor when comparing the different types of feet and ankle units. I'm
curious as to how important it is to feel the foot interact with the floor
. . . .feedback that is diminished or muted by a multiaxial foot or ankle
unit.
I suspect that that amputees with higher activity levels would appreciate
the motion afforded by a multiaxial unit, while new amputees or those with
poorer balance might appreciate feeling a flat, stable spot they can feel
as opposed to super flexible ankles that they have to always keep their
balance on. I'm particularly interested to hear from bilateral amputees on
this topic as they don't have a good leg to get proproiceptive feedback and
to compensate with.

Randy McFarland, CPO


Here are the replies: (with a blank line between each response)

I'm a young DAK amp and went for the good stuff from the jump...my thinking
was that I was athletic enough to want to learn with the gear that I was
going to be driving. I know that that decision is up for discussion, but
being a stubborn jock, I decided that this was the route for me. I convinced
my prosth to let me drive every foot I wanted until I was happy. I didn't
want some basic sach model and then have to make the switch to the tekked out
shit (O&P lingo). I wiped out alot, but I didn't attribute that to the feet
but the the learning process. I need the dynamic response I get from the
more torque-cool models. Trouble is that I am so rough on units that it's
hard not to experience substantial breakdown and busted wheels. Make any
sense...I'm shooting off the top of my head here and not organizing in any
way. I use different units for different activities. I obviously can't use
jock feet for long walking and less strenuous activities. I'll give you the
specifics if you're interested.
DAK 22/new transfem amp.

   I have been trying to get clearer about this myself although my
suppositions are different than yours. I believe ankle motion is important
psychologically and well as biomecanically especially in the beginning.

    I prefer the College Park over any static foot - the ankle action
cushions the impact of the step and helps the roll over to the toe become
more smooth and less jarring.
    There is never a feeling of finding the balance. Not at all, in fact the
slight movement actually helps maintain the balance because it helps adjust
for minor weight shifts without having to move the foot to re-stablish a firm
stance.
    It also helps when you are on an incline or other surface that is not
perfectly flat. With the static foot, the knee was always in jeopardy of
collapsing because the foot could never be placed flat enough to maintain
balance.

I have the same clinical impression you do: that unsteady folks like stable
bases and amps with great balance often prefer mobile bases. But, I'd be
much more interested in what the amputees have to say on this matter.

    If the pt is just transferring then you might want to limit motion.
Too much motion when standing or ambulating can certainly be a problem but
remember that stiffer bumpers can be used to limit motion.
    I just put a bilat BK on Endolite ankles with orange balls and blue
(stiffer) snubbers to give him the stability you are concerned with. I think
when he gets his strength and balance he may want the more flexible bumpers.
    I think we should go for ankle motion , stiffen as necessary and go to a
stiffer foot entirely if needed- rather than the other direction.
There may be too much pressure to pick the right foot the first time and that
just may not be what the reality is.

i will try my best to answer this question.
i am an ak, bk, and i wear seattle lite feet with endolite ankles.
i was wearing vsp prior to this arrangement.
for the bk, i am currently wearing an iceross pin system, (which i am not
tolerating well, and will be going back to the supercondylar suspension next
week) as far as the ankle motion, i like the fact that in a standing
position i can bend the knee without putting the foot up on the toe. as i
try to get weight off the stump as much as possible, this is a must.
but i have been wearing this system for over a year, and am finding that the
wear and tear on my knee is much more without the vsp foot. i wanted to add
a vertical shock pylon to this set up that i am wearing now, but i apparently
do not have enough room to add this.
i am seriously considering going back to the vsp foot. but it does remain to
be seen.
as i understand it, the adding of the ankle may dampen the function of the
foot when walking? being a double it is hard for me to tell the difference.
i also have so many varibles that may contribute to this, but i have no
problem walking with this ankle. it is stable.
     fFor the ak, i am wearing a flexible brim suction socket, with a black
max sns knee, seattle lite foot with endolite ankle. this knee has always
been very stable for me, so i feel that the ankle made the ak a tad
unstable, so i had the most bumpers put in, which i know defeats the purpose.
  again, i went from the vsp foot, to this set up, and while i have no
problem walking on these components, i'm thinking the vsp foot was a tad
easier on my hip.
all in all, i have no trouble walking on these components.
although i am not high activity, i do get around on the components well
enough, this is separate from the fact that my sockets do not fit well. i
am not sure i would have a different opinion of these components if my
sockets were great.
hope this helps.