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What is Arterial insufficiency ulcer and explain in detail?
Arterial insufficiency ulcers (also known as ischemic ulcers, or ischemic wounds) are mostly located on the lateral surface of the ankle or the distal digits. They are commonly caused by peripheral artery disease (PAD).

Characteristics
The ulcer has punched-out appearance. It is intensely painful. It has gray or yellow fibrotic base and undermining skin margins. Pulses are not palpable. Associated skin changes may be observed, such as thin shiny skin and absence of hair. They are most common on distal ends of limbs. A special type of ischemic ulcer developing in duodenum after severe burns is called Curlings ulcer.

Cause
The ulcers are caused by lack of blood flow to the capillary beds of the lower extremities. Most often endothelial dysfunction is causative factor in diabetic microangiopathy and macroangiopathy. In microangiopathy, neuropathy and autoregulation of capillaries leads to poor perfusion of tissues, especially wound base. When pressure is placed on the skin, the skin is damaged and is unable to be repaired due to the lack of blood perfusing the tissue. The wound has a characteristic deep, punched out look, often extending down to the tendons.  The wounds are very painful.

Diagnosis
The lesion can be easily identified clinically. Arterial doppler and pulse volume recordings are performed for baseline assessment of blood flow. Radiographs may be necessary to rule out osteomyelitis.

Differential diagnoses
Neuropathic ulcer
Gangrene
Infected wound

Management
The prevalence of arterial insufficiency ulcers among people with Diabetes is high due to decreased blood flow caused by the thinning of arteries and the lack of sensation due to diabetic neuropathy.  Prevention is the first step in avoiding the development of an arterial insufficiency ulcer