HAND-ARM VIBRATION SYNDROME (HAV)1

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 anddexterity;

inability to perform intricate tasks.

Musculoskeletal disturbances

TABLE 1 : Some tools associated with HAVs

SANDER / BUFFERS: Orbital sanders Oscillating (jitter-bug) Rotary burrs Floor polishers / buffers

GUNS: Hilte Rivetting Chipping Fettling Needle Kango

GRINDERS: Pedestal grinders Disc grinders Swing-beam grinders Angle grinders Straight grinders Orthodontic

DRILLS: Jack-leg Stoper Plugger Jack hammer Spade Diamond Dental

TABLE 1 : Some tools associated with HAVs- continued

OTHER: High pressure hoses Swaging Vibrating pokers (concrete) Grass trimmers

SAWS: Chain Brush Band Concrete Block

IMPACT: Wrenches Pneumatic screwdrivers Pneumatic knives

Some occupations associated with HAVs and type of tool

Saws, screwdrivers, wrenches & needle guns

Carpenters

Block saws Bricklayers

Wrenches, screwdrivers,

Grinders, sanders, buffers & pneumatic knives

Autobody shop workers

Wrenches, screwdrivers.

Grinders, sanders & buffers

Assembly workers

- aircraft - vehicle

TYPE OF TOOLSOCCUPATIONS

Some occupations associated with HAVs and type of tool - continued

Grinders (various), fettling & chipping guns

Foundry men

Chainsaws, & brush saws Foresters

Hilte guns, & screwdrivers Electricians

Drills (various) Die shop workers

Guns (various), jack hammers, & vibrating pokers

Construction workers

TYPE OF TOOLSOCCUPATIONS

Some occupations associated with HAVs and type of tool - continued

Drills (various) Miners

Grinders, & impact wrenches Millwrights

Wrenches, & grinders Mechanics

Jack hammers, vibrating pokers,

& concrete saws

Labourers

Wrenches, grinders (various) Iron workers

TYPE OF TOOLSOCCUPATIONS

Some occupations associated with HAVs and type of tool - continued

Grinders & fettling tools Welders

Rivetting guns & wrenches Rivetters

Handles & tongs Press operators

Hilte guns Pipe Fitters

TYPE OF TOOLSOCCUPATIONS

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 post-cold 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 any reactive hyperaemia while immersed, and delay in recovery afterwards.

o

HAV:Laboratory tests:

• Doppler studies

• Blood pressure of an affected digit pre- and post-cold 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

Intermittent or persistent numbness,

Reduced tactile discrimination and / or

Manipulative dexterity.

3 SN

Intermittent or persistent numbness,

reduced sensory perception.

2 SN

Intermittent numbness,

with or without tingling.

1 SN

Exposed to vibration but no symptoms.0 SN

SYMPTOMSSTAGE

*

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

As in stage 3, with trophic skin changes in the finger tips.

Very Severe

4

Frequent attacks affecting all phalanges of the most fingers.

Severe3

Occasional attacks affecting distal and middle (rarely also proximal) phalanges of one or more fingers.

Moderate2

Occasional attacks affecting only the tips of one or more fingers

Mild1

No attacks.0

DESCRIPTIONGRADESTAGE

*

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.