Fig. 1. Effects of morphogen priming of engineered mesenchymal condensations and in vivo mechanical loading on longitudinal bone formation and bone accumulation rate.

(A) Longitudinal quantification of bone volume at weeks 4, 8, and 12 by in vivo microCT (n = 4 to 11 per group). Data are shown as means ± SD. (B) Bone volume accumulation rate, defined as bone volume accrual over each 4-week interval. Box plots display median as horizontal line, mean as +, interquartile range as boxes, and minimum/maximum range as whiskers. (C) Representative three-dimensional (3D) microCT reconstructions showing bone formation per group over time. Representative samples were selected on the basis of mean bone volume at week 12. Scale bars, 3 mm. Comparisons between groups were evaluated by two-way repeated measures analysis of variance (ANOVA) with Tukey’s post hoc tests. Repeated significance indicator letters (a, b, and c) signify P > 0.05, while groups with distinct indicators signify P < 0.05 at each time point. Comparisons between time points were not assessed.