Raynauds phenomenon, Raynauds disease and Raynauds syndrome:

Raynauds Phenomenon:

Raynauds Phenomenon is the name given to the classic colour changes seen in the fingers and sometimes the toes (see pictures).

The classical colour changes are WHITE ---> BLUE ---> RED.

The WHITE - is due to spasm of the digital arteries, stopping any blood getting into the fingers at all

The BLUE - is due to the digital arteries starting to relax and some blood seeping into the fingers. As the tissues haven't had blood and oxygen for some time, the tissue take the oxygen out quickly, leaving the blood looking very blue.

The RED - is due to "reactive hyperaemia". In other words, when blood starts getting back into the tissues, the carbon dioxide and other waste products of the cells and tissues in the fingers cause the digital arteries to dilate - letting much more blood than normal into the fingers. They therefore go very hot and red.

Raynauds Disease:

When the Raynauds Phenomenon is seen, and an underlying medical cause is found, it is called Raynauds disease.

Such causes can be pressure on the subclavian artery by muscle or cervical rib, narrowing of the subclavian, axillary or brachial arteries, or abnormalities of the blood itself.

All of these causes need to be tested for to find out if the Raynauds Phenomenon is being caused by a specific problem - and whether this can be cured.

Raynauds Syndrome:

If no cause is found for the Raynauds Phenomenon, it is then called Raynauds Syndrome. The word Syndrome means "a collection of symptoms or signs that occur together".