0000000000061040
AUTHOR
H. Dupuis
Immediate Effects of Vibration Transmitted to the Hand
Summary Three different research projects have been accomplished on the problems: biomechanical behaviour of the hand-arm-system; subjective sensation; physiological changes. Some of the main results were:—the wrist and—with smaller amplifications—the elbow show resonances at low vibration frequencies (10–20 Hz);—with constant acceleration subjective perception decreases with increasing frequency;—application of static grip force—without vibration—causes significant reduction of the skin temperature, which under vibration stress remains at the same lowered level.
A reanalysis of spinal motion during vibration
Calibrated film of the motion of the lumbar spine during vibration was reanalysed, making use of a number of computer based techniques to improve accuracy and reduce measurement noise. The results demonstrated resonant behaviour at about 4 Hz and indicated that at vibration levels of the order of 1 m/s2 there exists bending of the order of 1° (peak to peak) between adjacent vertebrae in the lumbar spine. The bending is complex and involves phase differences along the spine and possibly a rocking motion of the pelvis.
Socio-medicinal aspects of vibration-induced white finger disease
The influence of vibration-induced white finger disease on the quality of life and possible social consequences is the subject of the study presented herein.The data acquisition was carried out by means of a standardized questionnaire. Parameters such as quality of life, professional practice, prevention and social security were assessed among other things.Nearly three quarters of the interviewees (n = 115) did not consult a physician with the occurrence of the first complaints. Physicians frequently made the correct diagnosis only with delay. From the first occurrence of symptoms to the acknowledgment as an occupational disease 0.5-34.5 years had usually elapsed. The quality of life affect…
DOSE–RESPONSE RELATIONSHIPS BETWEEN WHOLE-BODY VIBRATION AND LUMBAR DISK DISEASE—A FIELD STUDY ON 388 DRIVERS OF DIFFERENT VEHICLES
Abstract In a longitudinal study, the dose–response relationships between long term occupational exposure to whole-body vibration and degenerative processes in the lumbar spine caused by the lumbar disks were examined. From 1990 to 1992, 388 vibration-exposed workers from different driving jobs were examined medically and by lumbar X-ray. For each individual, a history of all exposure conditions was recorded, and a cumulative vibration dose was calculated allowing comparisons between groups of low, middle, and high intensity of exposure. 310 subjects were selected for a follow-up four years later, of whom 90·6% (n=281) agreed to participate. In comparing the exposure groups, the results ind…
Ermittlung des biomechanischen Schwingungsverhaltens menschlicher Bulbi mit Video-Technik
Mechanische Schwingungen konnen die visuelle Wahrnehmung beeintrachtigen. Das ist vor allem dann zu erwarten, wenn der Glaskorper des Auges in Resonanzschwingungen gerat. Experimente mit 8 Versuchspersonen und je einer Wiederholung dienten der Ermittlung des frequenzabhangigen biomechanischen Ubertragungsverhaltens von mechanischen Schwingungen zwischen Schadel und Bulbus. Die Bewegungen eines Reflexpunktes der angestrahlten Hornhaut und eines Lichtpunktes auf der Stirn wurden von einer Fernsehkamera erfast und uber ein Multipoint-X-Y-Tracker-System mit Direktschreiber registriert. Die Auswertung hat — ahnlich wie bei Tierexperimenten mit anderer Methodik-typische Resonanzkurven der Bulbi m…