Patient suffering from dry gangrene of his left foot.
Dry gangrene is a form of coagulative necrosis that develops in ischemic tissue, where the blood supply is inadequate to keep tissue viable. It is not a disease itself, but a symptom of other diseases. The term dry is used only when referring to a limb or to the gut (in other locations, this same type of necrosis is called an infarction, such as myocardial infarction). Dry gangrene is often due to peripheral artery disease, but can be due to acute limb ischemia. As a result, people with arteriosclerosis, high cholesterol, diabetes and smokers commonly have dry gangrene. The limited oxygen in the ischemic limb limits putrefaction and bacteria fail to survive. The affected part is dry, shrunken, and dark reddish-black. The line of separation usually brings about complete separation, with eventual falling off of the gangrenous tissue if it is not removed surgically, a process called autoamputation. Credit: @clinical_surgery
Surgical amputation if limb is at this point of diagnosis. To prevent from getting to this point, sometimes femoral, popliteal bypass can be performed to increase vascular flow to affected foot