View Full Version : Flexural rigidity of bones

10-05-1992, 11:18 PM
Dear Bone Testers:

Further to my comments on Moshe Nissan's queries on the flexural testing
of long-bones, I remembered a comprehensive technique developed by one of
his colleagues (Dr Amy Foux) during a Research Fellowship spent at the
National Research Council of Canada around 1986.

This technique involved the development of a polar plot of the Flexural
Rigidity (EI) of the bone and involved three-point bending on a sample
that was constrained to bend in a single plane. By testing the bone at a
series of angular rotations about its long axis, a polar plot was
developed. They reported the use of Cerralow 117 ( a eutectic bismuth alloy)
for the potting of the bones.

I believe this technique may rely upon an assumption that EI is constant
over the test-section - i.e. the bone that is left between the potted ends;
however, this approach is far more meaningful than testing the bone at some
unknown angle relative to its principal geometric axes.

The paper on the technique was presented to the 12th Canadian Medical and
Biological Engineering Conference held in Vancouver, Canada in 1986:

Foux,A., Black,R.C. and Skrypnyk,R. (1986): Polar flexural rigidity
profile, pp 144-145. Published by the Canadian Medical and Biological
Engineering Society, Building M-50, National Research Council of Canada,
Montreal Road, Ottawa, Ontario, Canada, K1A 0R8, $25 Canadian.
Phone 613-993-1686. FAX 613-954-2216.

This technique was used subsequently to evaluate bone healing and led to a
separate report at the 35th Annual Meeting of the Orthopaedic Research
Society held between 6-9 February 1989 in Las Vegas, Nevada, USA:

Black,R.C., Foux,A. and Uhthoff,H. (1989): Bone healing evaluation by using
the polar flexural rigity profile. Trans ORS 14:478. One page. The
proceedings are available from The Orthopaedic Research Society, 222 South
Prospect Avenue, Park Ridge, Illinois 60068, USA at a cost of $35 USA which
includes postage. Phone 312-698-1625.

If Dr Foux is still at the Technion then it would seem that a contact there
might produce some useful information and references.

Best wishes:

Bryan Finlay, PhD 519-663-3063
Director of Orthopaedic Research 519-663-3904 FAX
University Hospital
P.O. Box 5339
London, Ontario, CANADA, N6A 5A5