XRM Imaging to Evaluate Osteocyte
Direction of Bone Quality
Virginia L. Ferguson, Ph.D.

Bone is highly adaptive and remodels in response to strains that are sensed by osteocytes. These cells exist in micrometer-sized bony ‘caves’ called lacunae and extend dendrites to form complex, interconnected networks throughout bone tissue for sensing strain and communication. While numerous, osteocytes are difficult to study as they are encased within the bone and their extraction by destructive means is challenging.
X-ray microscopy (XRM) makes it possible to visualize the bony lacunae and bone tissue surrounding osteocytes in situ. Here, we describe the optimization of methods developed in our lab to visualize hundreds to thousands of osteocyte lacunae. We also describe how we analyze these osteocyte lacunar networks using spatial statistics to demonstrate how these cells adapt to the removal of normal mechanical loading in a spaceflight study of mice on the International Space Station. Finally, we demonstrate preliminary results where we are using reference materials to quantify the tissue mineral density in locations surrounding osteocytes.