Fig. 1.

(A) Transverse tibial cross section from finite-element model²¹ showing distribution of axial strain (strain component along the tibial axis, normal to the page) during axial compression. (B) µCT image of tibia from 22-month-old BALB/c mouse showing location of gauges for experimental strain measurements. Strain data were scaled based on beam theory to estimate strain values at sites of peak tension and compression on both endocortical and periosteal surfaces. (C) Linear force-strain relationship for strain at the peak endocortical site. Strain magnitude (mean ± SD) did not differ significantly between 7- and 22-month-old tibias. In vivo loading was performed at 8, 10, and 12 N force levels (+ site of peak periosteal compressive strain; ++ site of peak endocortical compressive strain; * site of peak periosteal tensile strain; ** site of peak endocortical tensile strain).