This type of ulcer is the most common of chronic leg ulcers. Of every 10 cases of leg ulcer, about six or seven are due to venous disease.
A venous ulcer is caused by the increased pressure of blood in the veins. Leg veins contain important valves that permit blood to flow only toward the heart. If the valves of the deep veins or the veins themselves become damaged, high pressure in the veins can develop due to the large volume of pooled blood (venous hypertension). Valve damage is mostly due to previous deep vein thrombosis (DVT), either diagnosed or unknown. Varicose veins and age are also factors. Venous ulcers usually occur on the lower calf and are associated with calf and ankle swelling.
If one or more leg arteries become narrowed or blocked, an ulcer may develop. A lack of arterial blood supply to the tissues is called ischaemia. Ischaemic ulcers tend to occur on the toes, foot and calf. Of every 10 cases of leg ulcers, about one or two are due to ischaemia.
Vasculitis is caused by the inflammation of arteries, usually the small arteries (arterioles). Larger arteries can also be affected. The inflammation may be caused by a wide range of conditions. This type of ulcer is often very painful. Of every 20 cases of leg ulcers, about one is a vasculitic ulcer.
Damage to the nerves of the leg can result in ulcers developing as the protective effects of pain are lost. These “neuropathic ulcers” commonly occur over the tips of the toes, side of the foot, the heel and bony prominences. They are often painless. Diabetes is the most common cause of neuropathic ulcers, with spinal injuries and other diseases causing some cases. Of every 10 cases of leg ulcers, about one or two are a neuropathic ulcer. A neuropathic ulcer may also be a part of an arterial or venous ulcer.