However, the presence of mediacalcosis, making the arteries incompressible, limits the interpretation of IPS. However, ALL affects 50% of diabetic patients after 20 years of disease with predominant involvement in the infra-popliteal gland consisting mainly of mediacalcosis, but often respecting the arteries of the foot.~The recommendations of the French-speaking Association for the Study of Diabetes and Metabolic Diseases in 1997 and of the American Diabetes Association in 2001, recommended the SPI and the realization of ultrasound for the diagnosis of ALL. Some authors have shown that SPI can be falsely normal with 4.3 times more false negative ankle SPI in diabetics compared to the general population. This is why this measurement of the SPI is coupled with the measurement of the pressure of the big toe (PGT) or even the transcutaneous measurement of the oxygen pressure (TcPO2) as recommended by the American Heart Association (AHA) and the American College of Cardiology (ACC) in 2005, in case of uninterpretable IPS.~The subjects at risk of mediacalcosis are: diabetics, renal insufficiency and the very elderly.~A recent thesis work confirmed that the SPI alone was not reliable as a screening tool in diabetic patients, with good sensitivity of the measurement of PGT.~What about a population over the age of 70, without diabetes and without kidney failure?
Arteriopathy of the lower limbs (ALL) is defined by a decreased ankle perfusion pressure with a systolic pressure index (SPI) <0.9, and constitutes the most advanced situation in terms of cardiovascular prognosis with in 20 % of cases of lesions associated with the heart and / or coronary heart. The severity of ALL is linked to the risk of a cardiovascular event, hence the need for a hemodynamic evaluation which is mainly based on the measurement of SPI.