Previous studies have shown that years of working with hand-held power tools
can cause hand-arm vibration syndrome, also known as HAVS. Now, researchers at
the Medical College of Wisconsin are taking a closer look at what causes the
problem and how to prevent it.
Using a rat-tail vibration model, a team of researchers led by Danny Riley,
Ph.D., professor of cellular biology, neurobiology and anatomy, demonstrated
that four hours of vibration causes blood vessel constriction and produces
damage to arterial smooth muscle and the endothelial cells that line the
The researchers also showed that blocking vasoconstriction by premedicating the
animal with nifedipine, a calcium blocker, to prevent smooth muscle contraction
during vibration, prevented arterial damage.
According to Riley, these findings indicate that vibration and blood vessel
constriction act synergistically to create the damage that eventually leads to
vibration syndrome. Until now, the researchers say, scientists knew very little
about the early stages of HAVS. In its late stages, the syndrome is
"The potential for harm by vibrating tools is underappreciated by the public
and not well known," Riley said. "Knowing what happens early on would not only
aid awareness but also help formulate preventive strategies, better screening
procedures and specific treatment of HAVS before it becomes irreversible."
AplusA-online.de - Source: Medical College of Wisconsin