affected limb. In 1903 H. Batty Shaw reported that in three cases the pain was so severe, and that the affected extremities are so useless, that amputation was performed. Differences with Raynaud's disease Back in 1899 Thomas Barlow had already summarized with great detail the contrast between erythromelalgia and Raynaud's disease as following: Dependence produces considerable increase of the dusky red or violaceous tint of the extremity affected; the arteries in this position of the limb may pulsate forcibly; pain is common, sometimes constant, and more especially when the limb is dependent or parts pressed upon; in wintry weather, or on the application of cold, the conditions are relieved; on the other hand, warmth and summer weather increases pain; there is no loss of sensation, but there may be increased sensitiveness; the local temperature of the affected parts may be raised or lowered; gangrene does not occur; the affection is asymmetrical; there is a certain amount of swelling, sometimes allowing pitting on pressure, sometimes not; incisions over such swelling, even down to the bone, have proved useless; excessive pain on pressure upon the nerves supplying the parts affected is not found; muscular wasting is found, but explainable by the disuse of the limb, and is not at all as severe as in cases of disease of the peripheral nerves; a reaction of degeneration in the nerves of the affected parts has not been found; the deep reflexes, with few exceptions, are not reduced. Footnotes External links Channelopathies Peripheral nervous system disorders Vascular-related cutaneous conditions Diseases of arteries, arterioles and capillaries Rare diseases