Classification by Symptoms

Staging in PAD is done according to the patient's complaints. This is gauged by the walking distance reached before pain begins. If intermittent claudication is accompanied by a condition of chronically reduced circulation in the extremities, which in turn makes the leg subject to amputation (continuing pain at rest or ulceration of the feet or toes combined with a systolic ankle arterial pressure of < 50 mm Hg), this is called a critical leg ischemia.
According to Fontaine, four stages are to be distinguished depending upon the severity of the intermittent claudication:


I. Asymptomatic, with proven stenosis (ankle-brachial index < 0.9)

II. Intermittent claudication

  • Sufficient compensation, > 200 m (pain-free) walking distance and subjectively sufficient
  • Insufficient compensation, < 200 m walking distance and subjectively insufficient

III. Pain at rest (mostly in toes or the front part of the foot)

IV. Necrosis, ulceration

  • Leg is not endangered, ailment arising from external wound of
    level II, also called complicated level II
  • Leg in acute danger

 

 

Memo1:

Stage II is often subdivided into stage IIa (maximum claudication distance > 200 m) and stage IIb (maximum claudication distance < 200 m); a clinically more relevant distinction would be according to “Claudication distance subjectively satisfactory/little discomfort” and “Claudication distance unsatisfactory/great discomfort”.

 

Trauma (pressure points, pedicure etc.) or concomitant diseases (such as chronic venous insufficiency) can also give rise to necroses and ulcers in stage I and II. Because of their better prognosis, these lesions should be distinguished from stage IV necroses and called “complicated stage I and II”. True stage III or IV (“critical ischemia of the extremities”) is characterized by resting pain which persists for at least two weeks and the occurrence of spontaneous necroses with a systolic peripheral arterial pressure of < 50 mm Hg.