Direct mechanical energies applied to the body can cause serious harm.
This page will give an introduction to Hand Arm Vibration Syndrome -
a range of symptoms and signs, which in the past has included terms such
as Vibration White Finger (VWF). As the name implies it is caused by vibration
being transmitted to the human body via the hand. HAVS can be responsible
for substantial physical impairment, disability, handicap and distress.
The extent of this has only been widely accepted relatively recently.
Thus relatively high frequency waves conducted through the air i.e.
noise, can cause noise induced hearing loss.
Relatively lower frequencies conducted through solids (vibration) in
close contact with the body can transmit their energy to the body and also
cause harm. Usually vibration is transmitted through the hand and arm and
could cause Hand Arm Vibration Syndrome (HAVS).
The lowest range of frequencies usually apply to the body as a whole
and can cause problems such as motion sickness.
A number of occupations can involve exposures which may lead to HAVS.
These range from the use of chain saws in forestry, pneumatic drills in
digging and mining, fettling tools in metal working and so on.
Other exposures may contribute to increasing the likelihood and/or
severity of HAVS, - these include cold and tobacco
The clinical manifestations consist generally of two main aspects:
Vascular - responsible for blanching of the fingers (hence 'white finger'),
especially after exposure to cold and with delayed/poor recovery thereafter.
There are similarities between these manifestations and Raynaud's disease.
Neurological - responsible for the subjective numbness, tingling as
well as pain, and the associated objective neurological sensory deficits
- to fine touch discrimination, temperature, etc.
There may be other manifestations related to the above e.g. damage to
bone and muscle. Dupuytren's contracture (usually affects one of the flexor
tendons of the ring finger) might also be the consequence of cumulative
trauma to the palm of the hand.