Subtle biphasic relationship is observed between cell migration speed and CG scaffold strut modulus; pore-size-dependent variation in cell speed is not explained by the variation in scaffold strut flexural rigidity. (*A*) Tetrakaidecahedral unit cell model for CG scaffold. For a series of scaffolds with a constant relative density, those with larger pore sizes, *d*_{1} (*left*), exhibit struts that are longer and thicker than a scaffold with smaller pore sizes, *d*_{2} (*right*). The longer/thicker struts have a greater flexural rigidity (*E*_{s} × *I*) than the shorter/thinner struts, and would deform less under a constant cell-applied traction force. If changes in strut *E*_{s} × *I* explain the pore-size-dependent effect on cell motility, cell speed would be expected to decrease with increasing strut modulus. (*B*) Average speed of NR6 cells migrating in scaffolds with a constant microstructure (pore size 96 *μ*m) but with varying strut modulus (over the same range as due to changes in strut *E*_{s} × *I*) shown via box-and-whisker (*left*) and mean ± SE (*right*) plots. From left to right, *N* = 116, 188, 191, and 79, respectively. Distinct from the concept of decreasing cell speed with increasing modulus, as predicted if the pore-size-dependent effects on motility are due to changes in strut *E*_{s} × *I*, a subtle biphasic relationship is seen between cell speed and substrate modulus. Statistical significance (**p* < 0.005) is determined by pairwise Kolmogorov-Smirnov test for nonnormally distributed data sets.

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