Aims: To follow up vibration induced white finger (VWF) in a selected group of 73 vibration exposed
workers who claimed unsuccessfully for VWF compensation at a first examination.
Methods: The VWF claimants were sent to our unit by the National Insurance Institute. The basic
compensatory criteria included a positive history of VWF and abnormal cold response of the digital
arteries. Following the first unsuccessful examination, over a mean time period of 4.1 (range 1–11) years
the National Insurance Institute requested a second examination for all 73 claimants and a third
examination for 29. During the follow up period, all subjects continued to work with vibratory tools.
Results: There were 14 new cases who reported white finger during the follow up period. In the new VWF
cases, finger blanching attacks became visible after about 3.5 years since the first examination. All
incident cases of anamnestic VWF showed an abnormal cold response in the digital arteries and obtained
compensation according to the basic compensatory criteria. In the entire sample of VWF claimants, there
was a discrepancy between positive history of VWF symptoms at medical interview (55%) and abnormal
cold provocation outcomes (19%). Digital arterial hyperresponsiveness to cold was associated with both
VWF symptoms and the duration of vibration exposure since the first examination. Over the follow up
period, a significant increase in the vasoconstrictor response to cold was observed in the vibration
exposed workers with no symptoms of finger whiteness. Abnormal cold response was not associated with
either age or smoking habit.
Conclusions: Cold test measuring finger systolic blood pressure may be considered a useful laboratory
method to confirm objectively VWF symptoms and to disclose abnormal cold induced vasoconstrictor
response in vibration exposed workers with a negative history of VWF. Medical interview outcomes should
be interpreted with caution in medicolegal situations involving VWF claimants.
