Deficiencies of the Stockholm vascular grading scale for hand-arm vibration

The internationally accepted Stockholm vascular grading scale for vibration white finger (VWF) has shortcomings that have received insufficient attention: some of its key descriptors require further definition and, more crucially, the scale does not suit all possible patterns of symptoms. To determine whether these shortcomings matter in practice, an attempt was made to apply the Stockholm vascular scale to 92 consecutive cases of VWF assessed by one area office of the Health and Safety Executive in the United Kingdom.

Case definition was based on clinical history and examination, but blanching was confirmed from observations of 34 men (37% of the cases). The 145 affected hands were graded under 2 alternative definitions of "frequent attacks"; and the 92 persons were graded using the same definitions according to the extent of blanching in their worse affected hand.

Depending on the choice of definition of frequent attacks, between 36% and 61% of the affected hands fell outside the scale and were unclassifiable. Thirty percent of the individual cases could not be classified under either definition, and 28% altered their grading according to the definition. The findings were broadly similar when the analysis was restricted to the 34 cases with observed blanching.

It was concluded that the Stockholm vascular scale does not encompass the full range of disease and that its grading is highly sensitive to different interpretations of "frequent attacks". Alternative approaches to clinical grading are required.