pneumatic hammer disease
Occupational Diseases / / May 19, 2016
Vibration - is the mechanical vibrations of elastic bodies.By the nature of the contact with the body of the working industrial vibration divided pas local (local) and total.This division is somewhat arbitrary, but it is convenient to practice.
strength of vibration effects on the body depends on the amount of vibrational energy absorbed, the most adequate expression of which is Velocity.
As a rule, industrial vibration has a complex range of vibrations with a wide range of frequencies.The nature of its impact is determined by the location of the maximum vibrational energy in a particular frequency range.The range of normalized rms on levels of local vibration frequency rate spans from 8 to 1000 Hz.According to the prevailing energy can be recovered low frequency (8-16 Hz), medium (16-64 Hz) and high frequency (64-1000 Hz) field.
Vibration disease - a complex of pathological changes observed in individuals regularly exposed to vibration.In this case there is a combination of a direct irritant and
clinical picture of vibration disease depends not only on the frequency characteristic of vibration, but also place its applications, features profession, presence of concomitant harmful factors, mode of operation.The leading place in the clinic of vibration diseases are disorders of the nervous and cardiovascular systems, as well as bone changes.Depending on the nature and vibration applications place to distinguish between three types of vibratory disease;
1) vibration disease from 'local' action vibration (low or high frequency);
2) vibration disease from the combined (total and "local") action of the medium and high frequency vibration;
3) vibration disease of the total action of low-frequency vibrations and shocks.
Vibration disease from the "local" vibration action observed in working with a variety of hand-held vibrator percussion and rotary action at frequencies from 8 to 150 Hz and above (in the metal industry - obrubschiki, chasers, riveters, mechanics, working with grinders, moulders;in the mining industry - drillers, sinker, and a number of other professions).
The clinical picture consists of symptoms of autonomic polyneuritis angiodystonia and phenomena with a prevailing tendency to spasm of peripheral vessels and capillaries zapustevaniyu.
Vibration low frequency (8-20 Hz) is predominantly vegetative polyneuritis phenomena and destruction of bones and joints, vibration of higher frequencies - angiospastic syndrome (attacks blanching of fingers).However, in practice there is often a combination of these and other symptoms.
Typical complaints: finger blanching attacks (especially in cooling), night pain and paresthesias in the hands (numbness, "Run Games and needles" in the fingers).
Objective symptoms: cyanosis and hypothermia brushes, easy fingertip swelling, excessive sweating of the palms and fingers.Positive "white spot symptom."White spots formed on the palm and fingers after a strong contraction of the past into a fist (for 5 seconds), after straightening them hold more than 10 seconds.Positive symptom Pal (disappearance or asymmetry of the radial artery pulsation with the rapid rise up the patient's hand).Positive test Bogolepova (one patient's hand is raised up, and the other - is omitted, this posture is maintained for 0.5 min, then both arms are extended horizontally on the pitch, the difference in the color of brushes normally smoothed out for 15 sec).Positive cold test (whitening of the fingers, solid or spotted, after lowering the patient's hand in water at 10-12 ° C for 3 min).
When Capillaroscopy nail bed there is a violation of tone of the capillaries, as well as changes in vascular permeability.
data plethysmography, oscilloscopes and rheovasography disclose a violation of the regulation of the tone of the large vessels in the shoulder and arm, resulting in asymmetry of their performance and violation of blood flow velocity.
important place in the clinical picture is occupied sensitivity disorders.
especially suffers vibration sensitivity, a decrease has been observed in the early stages of the disease.
most severely impaired sensitivity to pain, to a lesser extent - the temperature, even less - tactile.Musculo-articular sense usually suffers.
disorders in the motor areas are relatively rare (only in severe forms of the disease), they are shown a decrease in muscle tone and muscle strength, muscle hypotrophy small brush (large elevations and smallest finger intercostals muscles) and the weakening of their functions.
When expressed forms of the disease have been violations of the trophism of the skin and subcutaneous tissue brushes, nail, finger joints.When X-rays are detected violations of bone trophism.The disease usually occurs in the background of the general autonomic dysfunction or neurasthenic syndrome.In rare cases, it may develop an organic lesion of the spinal cord syringomyelia mud or lateral sclerosis.