Scientists uncover a new blood vessel in our bones.
The newly-discovered capillaries – called trans-cortical vessels (TCVs) – penetrate the hard shell of bones in mice.
The research was carried out by the University Duisburg-Essen, Germany, and led by Dr Anika Grüneboom, from the institute for experimental immunology and imaging.
Human anatomy is rarely the subject of scientific breakthroughs, with most experts being confident the major organs and tissues have already been discovered.
‘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,’ Dr Matthias Gunzer, study co-author and head of the institute, said.
He told NewScientist : ‘It’s totally crazy there are still things to find out about human anatomy – we have discovered blood vessels in a new place that we didn’t know about before.’
Professor Gunzer himself even took part – lying in a scanner for six hours while it imaged his lower leg.
The discovered capillaries connect the inner and outer membranes that surround bones.
They are thought to play a critical role in helping to transport blood in and out of the bones’ hard shell.
This blood also found to be rich in immune cells, which the capillaries carry from the bone marrow to the circulation.
Up until now, blood was assumed to enter long bones via arteries at the bones’ end or through the few vessels along the bones’ shaft, before passing through bone marrow and exiting the other end.
‘This is too oversimplified and does not correctly reflect the true natural situation,’ Professor Gunzer said.
The researchers believe TCV re-modelling could play a role in the healing of fractures.
To better understand this, they are calling for studies that investigate what ‘maintains’ these capillaries.