EFFECTS OF REHYDRATION STATE ON THE FLEXURAL PROPERTIES OF WHOLE MOUSE LONG BONES

The effects of bone water content during dehydration and rehydration o n the flexural properties of whole mouse femora were evaluated using t hree-point bending. The elastic and plastic flexural properties of the bones were determined on a dry mass normalized basis over dehydration times ranging from 0.25 to 48.0 hr; and (following complete dehydrati on) rehydration times ranging from 0.08 to 12.0 hr. Bones stored in ph ysiological saline for times < 1 hr served as the control group. As ex pected, dehydration produced increased stiffness and strength along wi th decreased ductility. Upon rehydration, a statistically significant linear dependence of mechanical properties on recovered free water was obtained for all parameters except the maximum load. Elastic mechanic al properties comparable to the controls were regained at differing ra tes and levels of recovered water content; however, after 3 hr of rehy dration there were no statistically significant differences with respe ct to the control values. The results of this study indicate that the original flexural properties of whole mouse femora are preserved by ai r dehydration and can be recovered using appropriate saline rehydratio n intervals.