Neurological and functional effects of short-term exposure to hand-arm vibration

• Published in: International archives of occupational and environmental health Vol. 71; no. 4; pp. 270 - 276
• Main Authors: MALCHAIRE, J, RODRIGUEZ DIAZ, L. S, PIETTE, A, GONCALVES AMARAL, F, DE SCHAETZEN, D
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.06.1998
• Subjects: Adult; Arm - innervation; Biological and medical sciences; Effects of various physical factors on living matter (vibrations, electric field, ultrasound, sound...); Fundamental and applied biological sciences. Psychology; Hand - innervation; Hand Strength - physiology; Humans; Male; Mechanoreceptors - physiology; Median Nerve - physiopathology; Motor Skills - physiology; Neurologic Examination; Occupational Exposure - adverse effects; Paresthesia - etiology; Paresthesia - physiopathology; Reaction Time - physiology; Sensory Thresholds - physiology; Tissues, organs and organisms biophysics; Vibration - adverse effects; Human; Vibration; Perception threshold; Psychophysics; Hand; Occupational environment; Manual aptitude; Short lasting; Stimulus duration; Sensorial perception; Upper limb; Biological effect; Performance
• ISSN: 0340-0131; 1432-1246
• DOI: 10.1007/s004200050280

The aim of the present study was to quantify the sensory and functional effects resulting from a short-duration (30 min) exposure to hand-arm vibration. Nine subjects went through nine laboratory experiments. For 32 min they grasped a handle vibrating at three different amplitudes (5, 20, and 80 ms-2) and at three frequencies (31.5, 125, and 500 Hz). Additionally, a reference experiment was conducted in which the handle did not vibrate. Three sensory tests [vibration perception threshold (VPT), pressure perception threshold (PPT), and distal sensory latency time (DSL)], two functional tests [Purdue peg-board (PPB) and maximal voluntary force (MVF)], and a questionnaire concerning the perceived paresthesia and numbness were completed before, during, and after exposure. A 32-min period of exposure to vibration leads to a temporary threshold shift (TTS) of the VPT and to the development of paresthesia and numbness. The VPT appears to vary with the exposure duration according to a first-order model with a time constant about equal to 3 min. The TTS increases with the vibration acceleration amplitude and is greater for an exposure frequency of 125 Hz than for that of 31.5 or 500 Hz. It is also greater at the test frequency 125 Hz than at 31.5 Hz. The other tests do not demonstrate any significant variation. In particular, the PPB test does not demonstrate any loss of dexterity. After some 30 min of exposure to vibration the VPTs are increased and paresthesia and numbness develop. However, these do not appear to influence significantly the capacity or performance at work.