Transcript HAND-ARM VIBRATION SYNDROME (HAV)

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HAND-ARM VIBRATION SYNDROME (HAV)
Results from exposure to vibration (4 to 5000 Hz);
Time exposure:
one month to 30 years
HAV:
Symptoms / Signs:
Circulatory (vasospasm) with local finger
blanching);
previously known as:
vibration-induced white finger
HAV:
First noticed on cold, wet, and windy morning,
in the tips of the fingers most affected by vibration.
Intermittent numbness or tingling often precedes
actual blanching.
Vasospasm rarely symmetrical, and reflects the
subject’s grip on the vibrating tool.
With continued exposure, vasospasm progresses
proximally, and to other fingers.
In advanced cases: cyanotic tinge, progressing to
trophic skin changes (gangrene).
Worse in smokers.
HAV:
Symptoms / Signs - continued:
Sensory & motor disturbances
 numbness, loss of finger co-ordination and
dexterity;
 inability to perform intricate tasks.
Musculoskeletal disturbances
TABLE 1 : Some tools associated with HAVs
DRILLS:
 Jack-leg
 Stoper
 Plugger
 Jack hammer
 Spade
 Diamond
 Dental
GUNS:
 Hilte
 Rivetting
 Chipping
 Fettling
 Needle
 Kango
GRINDERS:
 Pedestal grinders
 Disc grinders
 Swing-beam grinders
 Angle grinders
 Straight grinders
 Orthodontic
SANDER / BUFFERS:
 Orbital sanders
 Oscillating (jitter-bug)
 Rotary burrs
 Floor polishers / buffers
TABLE 1 : Some tools associated with HAVs- continued
IMPACT:
 Wrenches
 Pneumatic screwdrivers
 Pneumatic knives
SAWS:
 Chain
 Brush
 Band
 Concrete
 Block
OTHER:
 High pressure hoses
 Swaging
 Vibrating pokers (concrete)
 Grass trimmers
Some occupations associated with HAVs and
type of tool
OCCUPATIONS
Assembly workers
- aircraft
- vehicle
TYPE OF TOOLS
 Wrenches, screwdrivers.
Grinders, sanders & buffers
Autobody shop workers  Wrenches, screwdrivers,
Grinders, sanders, buffers &
pneumatic knives
Bricklayers
 Block saws
Carpenters
 Saws, screwdrivers, wrenches &
needle guns
Some occupations associated with HAVs and
type of tool - continued
OCCUPATIONS
TYPE OF TOOLS
Construction workers
 Guns (various), jack hammers, &
vibrating pokers
Die shop workers
 Drills (various)
Electricians
 Hilte guns, & screwdrivers
Foresters
 Chainsaws, & brush saws
Foundry men
 Grinders (various), fettling &
chipping guns
Some occupations associated with HAVs and
type of tool - continued
OCCUPATIONS
TYPE OF TOOLS
Iron workers
 Wrenches, grinders (various)
Labourers
 Jack hammers, vibrating pokers,
& concrete saws
Mechanics
 Wrenches, & grinders
Millwrights
 Grinders, & impact wrenches
Miners
 Drills (various)
Some occupations associated with HAVs and
type of tool - continued
OCCUPATIONS
TYPE OF TOOLS
Pipe Fitters
 Hilte guns
Press operators
 Handles & tongs
Rivetters
 Rivetting guns & wrenches
Welders
 Grinders & fettling tools
HAV:
Diagnosis:
Based on history, and on exclusion of other causes of
Raynaud’s phenomenon:
 primary Raynaud’s or constitutional white finger,
 local trauma to digital vessels,
 thoracic outlet syndrome,
 peripheral vascular disease,
 collagen diseases.
HAV:
Laboratory tests:
•
Doppler studies (for patency of limb blood
vessels and blood pressure ratios in peripheral
vessels);
HAV:
Laboratory tests:
•
Doppler studies
•
Blood pressure of an affected digit pre- and postcold stress), and cold air or water provocation
tests (immersion of the digits in water or air for 2
to 10 minutes at 5 to 15 C with recording of skin
temperature) to note anyo reactive hyperaemia
while immersed, and delay in recovery
afterwards.
HAV:
Laboratory tests:
•
Doppler studies
•
Blood pressure of an affected digit pre- and postcold stress), and cold air or water provocation
tests
•
Nerve conductions studies.
o
The Stockholm Workshop Scale for the Classification of
Sensorineural Affects of the Hand-arm
Vibration Syndrome*
STAGE
*
SYMPTOMS
0 SN
Exposed to vibration but no symptoms.
1 SN
Intermittent numbness,
with or without tingling.
2 SN
Intermittent or persistent numbness,
reduced sensory perception.
3 SN
Intermittent or persistent numbness,
Reduced tactile discrimination and / or
Manipulative dexterity.
The sensorineural stage to be established for each hand.
The Stockholm Workshop Scale for the classification of
Cold-Induced Raynaud’s Phenomenon in the Hand-arm
Vibration Syndrome *
STAGE GRADE
0
*
DESCRIPTION
No attacks.
1
Mild
Occasional attacks affecting only the tips of one or
more fingers
2
Moderate Occasional attacks affecting distal and middle
(rarely also proximal) phalanges of one or more
fingers.
3
Severe
Frequent attacks affecting all phalanges of the most
fingers.
4
Very
Severe
As in stage 3, with trophic skin changes in the
finger tips.
The staging is made separately for each hand. In the evaluation of the subject, the
grade of the disorder is indicated by the stages of both hands and the number of
affected fingers on each hand; example “2L(2) / 1R(1)”, “- / 3R(4)”, etc.
Management:
• Smoking cessation;
• Decrease or avoid exposure to vibration;
• Hold tools as lightly as possible, to decrease
vibration transmission;
• Decrease vibration at source (anti vibration tools
and proper servicing of tools;
• Ergonomic design (minimize strain on user):
 high power to weight ratio;
 low torque;
 non-slip surface of handles to reduce the need
to grip tightly.
Pharmacotherapy:
Calcium channel blockers.
________
1. Pelmear PL: Hand-Arm Vibration Syndrome.
Mastromatteo Oration 1998. Annual Scientific
Conference, OEMAC, October 6, 1998.