Various tissue types, including fibrous connective tissue, bone marrow, cartilage, woven and lamellar bone, coexist in healing bone. Similar to most bone tissue type, healing bone contains a lacuno-canalicular network (LCN) housing osteocytes. These cells are known to orchestrate bone remodeling in healthy bone by sensing mechanical strains and translating them into biochemical signals. The structure of the LCN is hypothesized to influence mineralization processes. Hence, the aim of the present study was to visualize and match spatial variations in the LCN topology with mineral characteristics, within and at the interfaces of the different tissue types that comprise healing bone. We applied a correlative multi-method approach to visualize the LCN architecture and quantify mineral particle size and orientation within healing femoral bone in a mouse osteotomy model (26 weeks old C57BL/6 mice). This approach revealed structural differences across several length scales during endochondral ossification within the following regions: calcified cartilage, bony callus, cortical bone and a transition zone between the cortical and callus region analyzed 21 days after the osteotomy. In this transition zone, we observed a continuous convergence of mineral characteristics and osteocyte lacunae shape as well as discontinuities in the lacunae volume and LCN connectivity. The bony callus exhibits a 34% higher lacunae number density and 40% larger lacunar volume compared to cortical bone. The presented correlations between LCN architecture and mineral characteristics improves our understanding of how bone develops during healing and may indicate a contribution of osteocytes to bone (re)modeling.

各种组织类型，包括纤维结缔组织、骨髓、软骨、编织骨和板层骨，共存于愈合骨中。与大多数骨组织类型相似，愈合骨包含一个容纳骨细胞的腔隙小管网络 (LCN)。众所周知，这些细胞通过感知机械应变并将其转化为生化信号来协调健康骨骼中的骨骼重塑。假设 LCN 的结构会影响成矿过程。因此，本研究的目的是可视化和匹配 LCN 拓扑结构中的空间变化与矿物特征，包括愈合骨的不同组织类型的内部和界面。我们应用相关的多方法方法来可视化 LCN 结构，并量化小鼠截骨模型（26 周龄 C57BL/6 小鼠）中愈合股骨内的矿物质颗粒大小和方向。这种方法揭示了以下区域内软骨内骨化过程中几个长度尺度的结构差异：钙化软骨、骨性愈伤组织、皮质骨以及在截骨术 21 天后分析的皮质和愈伤组织区域之间的过渡区。在这个过渡区，我们观察到矿物特征和骨细胞腔隙形状的连续收敛，以及腔隙体积和 LCN 连接的不连续性。与皮质骨相比，骨愈伤组织的腔隙数密度高 34%，腔隙体积大 40%。