Objectives: To compare the ankle of ankle and foe pressures as regards the diagnosis of critical ischaemia, its prognosis, and the need for vascular surgery. Design: University hospital-based retrospective study. Materials and methods: Fifty-seven patients (23 women and 34 men) with gangrene or rest pain had a haemodynamic evaluation combining ankle systolic pressure, toe pressure and cutaneous oximetry (tcPO(2)) with long-term follow-up (until death, for 44%). Results: After 2 years of follow-up, actuarial rates were 49 and 79% for survival and limb salvage, respectively Ankle and toe pressures gave vise to different subsets of patients, p<0.001, mainly because of the existence of a group of patients with very distal foot arterial disease. Low ankle pressure was linked to the risk of major amputation. Low toe pressure was linked to a great need for vascular surgery. Diabetes increased the risk of minor amputation. Conclusions: The concept of critical ischaemia remains clinically relevant. Haemodynamic quantitative data strengthen this concept, but ankle and toe pressures are not interchangeable parameters. For these reasons, toe pressures should be changed from a recommended to a mandatory haemodynamic parameter in the definition of critical ischaemia.