In the systematic sclérodermie, 15 to 25 % of the patients suffer from active digital ulcers and 35 to 50 % of the patients will make a digital ulcer. These digital ulcers are in touch with an obstructive digital arteriopathy, that is arterial hurts modifying the arterial flow. It thus seems interesting to have diagnostic tools allowing to make the diagnosis in particular upstream to the appearance of ulcers. At present, the digital pressures can be used.