Table 7.

Comparisons of fluid shear stress and drag force between aged CTL and Hypo bones under 3N tibial loading

	CTL Bone	Hypo Bone	Relative change (Hypo vs. CTL)
Shear stress on cell membrane (Pa)	5.9	7.9	+34%
Shearing force over 1μm cell process (pN)	2.72	3.38	+24%
Fluid drag force over 1μm cell process (pN)	18.4	12.0	−35%
Ratio of fluid drag over shearing force	6.8	3.5	−48%

Note: Both bones were loaded at 3N peak load at 0.5Hz; the fiber spacing for fibers in radius of 2nm was 13.4nm (CTL) and 17.4nm (Hypo), respectively (Table 6).