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Julie A. Martin
12-17-1996, 03:36 AM
Thank-you to all who replied to and expressed interest in my query in
late November:

>I am a graduate student researching the effects of immobilization on the
>mechanical and viscoelastic properties of the Achilles tendon. I plan to
>use an animal model in my study, in which the hind limbs of rabbits will be
>immobilized by means of a brace. Such a polyurethane brace, manufactured
>by a Japanese company (Takeuchi Prosthetics) has been reportedly used in
>similar studies focusing on osteoporosis. I have made several attempts to
>contact this company but to no avail.

>Is anyone famililar with this or any other company that makes braces
>specifically for small animals, and better yet, mature rabbits? I greatly
>appreciate any information.

>Julie Martin
>Musculoskeletal Research Laboratory
>University of Vermont

No one was familar with Takeuchi Prosthetics or any other manufacturer of
a suitable device. I received several suggestions to make my own braces,
and this has been my course of action. My main concern was in finding or
fabricating devices that could be removed and reapplied with relative
ease, since we have to habituate the animals to the restraint for a
period of time before applying the braces for the duration of the six
week immobilization period. We also want to be able to inspect the limb
if signs of a problem should arise, without the risk of altering the
position of the limb during the immobilization period.

We plan to use a polyurethane-impregnated fiberglass casting tape
(Vetcast) which is simply wrapped around the limb over a stockinette, a
layer of cotton wrap, and a layer of cast padding. The casting tape sets
within 5 minutes and provides "full body support" within 20 minutes. We
can then cut the cast in two halves, yielding an anterior and a posterior
piece. We are going to mold the braces on a carcass of a rabbit of the
desired size and apply them to the experimental animals with elastic
tape. The elastic tape is very sticky and should help in disuading the
animals from chewing the braces. We will also be reinforcing the braces
with aluminum rods, to lend additional stiffness as well as to provide
a template or jig for proper positioning of the limb. In the event that a
pre-fabricated brace cannot be fitted to a particular live animal, we will
have to anesthetize the animal and fashion a brace to it. Although this
shouldn't be a problem considering the quick curing time of the casting tape,
we would like to avoid it to eliminate the risk of injuring the animal
during the cutting of the cast.

I would be happy to let anyone interested know how this turns out, as
well as the specifics of the supplies we're using and the vendor. Thanks
again for all the help.

Julie Martin
University of Vermont