Raynaud's phenomenon in chain saw users. Hot and cold finger systolic pressures and nailfold capillary findings.

To gain insight into the physiopathology of Raynaud's phenomenon of occupational origin, finger systolic pressures under heat and cold, and results of nailfold capillary microscopy, were examined in 29 lumberjacks with Raynaud's phenomenon vibration syndrome (pathological group) and 24 lumberjacks without it (non-pathological group), and compared with the same values in 26 healthy matched manual workers not using a vibrating tool (controls). Vibration syndrome physiopathology seemed multifactorial, combining 5 features: a rise in brachial diastolic and systolic pressures in the pathological group compared with the two other groups. In lumberjacks with Raynaud's phenomenon, these rises seemed to be acquired, since they were not found when the workers were engaged; a reduction in the number of nailfold capillaries (9.4 +/- 2 per mm in the pathological group vs 11 +/- 2.5 in the controls, P less than 0.025); a rise in the brachial digital systolic gradient (P less than 0.025) in the pathological versus the non-pathological lumberjack group abnormal cold vascular tone, since at 15 degrees C finger systolic pressures in the pathological group were lower than pressures in both the control and non-pathological groups (P less than 0.05 and P less than 0.01, respectively), and at 10 degrees C, they were lower in the pathological than in the control group (P less than 0.01); Within the pathological group, individual paired comparisons between the most and least symptomatic finger revealed a rise in the cold vascular tone, and a reduction in the number of nailfold capillaries in the most symptomatic finger compared to the least symptomatic finger.(ABSTRACT TRUNCATED AT 250 WORDS)