ITHACA, N.Y. From athletes to individuals suffering from osteoporosis, bone fractures are usually the result of tiny cracks accumulating over time -- invisible rivulets of damage that, when coalesced, lead to that painful break.
Using cutting-edge X-ray techniques, Cornell University researchers have uncovered cellular-level detail of what happens when bone bears repetitive stress over time, visualizing damage at smaller scales than previously observed. Their work could offer clues into how bone fractures could be prevented.
Marjolein van der Meulen, professor of biomedical engineering, led the study published online March 5 in PLOS One using transmission X-ray microscopy at the Stanford Synchrotron Radiation Lightsource, part of the SLAC National Accelerator Laboratory.
Study and images: http://bit.ly/Yf70EN
Using the high-energy hard X-rays at SLAC's synchrotron, the researchers produced images of damage in sheep bone at a resolution of 30 nanometers -- several times better than standard imaging via X-ray microcomputed tomography, which is at best 2-4 microns in resolution. (A nanometer is one-billionth of a meter. For comparison, the width of a human hair is about 70 microns, or 70,000 nanometers.)
"In skeletal research, people have been trying to understand the role of damage," said van der Meulen, whose research is called mechanobiology -- how mechanics intersects with biological processes. "One of the things people have hypothesized is that damage is one of the stimuli that cells are sensing."
The inability of cells to repair microdamage over time ultimately contributes to the failure and breaking of bone, van der Meulen said. Until now, visualization techniques of microdamage were limited to lower resolution images. More detailed bone features, such as the small spaces called lacunae, where cells reside, and the microscopic canals between them
|Contact: Syl Kacapyr|