Twenty male chain saw operators between the ages of 46-60 working in-5℃ to 10℃ were studied. Fifteen of them had white finger. The frequency and acceleration level of chain saw was 65-160 Hz and 124 dB respectively.Thirty-four age and sex matched forest workers who had never used vibrating tools were also examined as control group. The research program was comprised of: (1) case history,physical, laboratory and radiographic examinations, (2) electrophysiolosical and motor function examinations, (3) peripheral circulatory function tests and (4) skin pathological and electronmicroscopic studies.
Our results illustrated the broad spectrum of pathologic abnormalities associated with the vibration syndrome. It is a multisystem disorder of the peripheral circulation, nerves, muscles, bones and joints of the hand and arm.Its pathogenesis is unclear but it is possibly related to direct microtrauma to the tissues as well as to Secondary trauma to blood vessels after long term exposure to vibration, cold and noise which results in circulatory insufficiency.Muscle weakness and bone degeneration also develop as a result of the heavy and strenuous work of lumbering.