The discovery of conduits never before seen in the bones of animals and humans could lead to a new understanding of the structure and function of human skeletal anatomy.
German researchers have found a network of thin blood vessels that act as a system of secret tunnels inside the bones.
The structure, never before detected by scientists, may be responsible for helping the blood and immune cells spread efficiently and quickly throughout the body.
“It is really unexpected being able to find a new and central anatomical structure that has not been described in any textbook in the 21st century,” study co-author Matthias Gunzer, a professor at the University of Duisburg-Essen in Germany, explained in a statement.
As explained in a paper published in Nature Metabolism, the newly-identified vessels are seen crossing the surface of bones to their interior.
Since bones are organs too, they have a system for blood circulation not unlike our softer organs.
These small channels, called “transcortical vessels” (TCVs), help explain how emergency medicine injections work in the body. In extreme cases, such as on battlefields, doctors do not always have the time or ability to find or access veins, and often inject drugs directly into the bone marrow of the wounded.
Despite the accumulated evidence of the existence of “complex blood supply in the bones”, the rapid changes of cells and fluids from the bone marrow to the circulation could never be explained.
That is until now.
The study authors suggest that the discovery of the vessels is a “missing link in the search for a fully functional closed circulatory system” which explains how blood flows in and out of bones.
“It’s totally crazy there are still things to find out about human anatomy,” Gunzer told New Scientist.
“We have discovered blood vessels in a new place that we didn’t know about before.”
According to the new study, the tibia of a mouse can contain more than 1,000 of these small vessels. More than 80% of arterial blood and 59% of venous blood would pass through these channels.
When analyzing the human anatomy, the scientists found evidence of the same type of TCV structures.
In our organisms, however, the channels are thicker and researchers recognize that more work is needed to confirm their exact function.