On Wed, 8 Oct 1997 17:00:39 -0400 Kim Susan J <[email protected]>
writes:
>Hi
>
>I am a physical therapy student trying to research on the area of
>amputee
>runner’s and sports injuries. If you have any information on common
>injuries related to this population and any treatment considerations,
>please write me at:
>
>email: [email protected]
>
I am a uni-lateral BK. I compete on off-road motorcycles, play fast
frisbee, and do just about anything else. I am not a runner, per se, but
I have a symmetric gait and can run and sprint quite well. Distance
running exceeds my attention span. But I can give you some anecdotal
feeback.
Think of socket fit as hydrostatic and not only as a contact of socket
interface, through skin, to bone. A good deal of the fit is a floating
of the bones in pressurized flesh. Fit is therefore compromised as the
volume of fluid decreases. While heavy physical activity while upright
adds fluid pressure within the lower limbs, the increased vascularization
along with closely-spaced and rapid loading cycles drives out fluid,
which directly affects fit, which directly impacts the fatigue of the
limb within the prosthesis. I do not get this effect when doing
activities as strenuous, but with breaks in between loadings for the
fluids to replenish and maintain a balance for good ‘float’. Example:
frisbee or racquetball.
The kinds of injuries I have experienced are almost always fatigue in
nature and subtle, and not due to single instances of high loads or
falls, etc. The fatigue takes place in the skin and sub-cutaneous
tissue, manifesting as underlying or surface soreness.
The poorer the fit and less compliant the liner (on bony BKs in
particular), the more rapidly fatigue takes place. Before I had more
sophisticated socket fit and equipment, such as OWW Alpha liner and my
College Park foot or Flex Foot, I would sometimes get soreness of the
distal tibia due to high load spikes impacting the bone. In `83 I had a
hard socket and SACH foot with belt suspension. I could run, but not
sustain running as the end of my leg would protest very quickly.
Hope this helps.
Chris Johnson
Director of Engineering,
College Park Industries, Inc.
(810) 294-7950 (at CPI), (616) 664-4173 (home office)
