The skin on the lower leg is dry, red and itchy, later brown pigment spots, weeping eczema and skin hardening form. An open area develops that simply does not heal. Almost one million people in Germany suffer from leg ulcers, predominantly at the bottom of a vein condition.
Incidence of leg ulcer
Leg ulcer tends to occur at older ages and has serious economic consequences. Nearly 15% of adult Germans are thought to have chronic venous disease – the most common cause of lower leg ulcers. Treatment costs for venous leg ulcers alone are estimated at about 1.5 billion euros in Germany, or 1-2% of the health insurance budget. And as the population ages, these are more likely to increase in the coming years. Effective prevention and therapy are therefore important.
How does a leg ulcer develop?
Poorly healing, deep wounds on the lower legs are almost always caused by vascular disease, not – as one might think at first glance – by skin disease. The ulcer develops on the basis of an undersupply of the tissue.
In more than 70% of cases, a venous disorder (venous leg ulcer) underlies, in about 8% an arterial vascular disease (arterial leg ulcer), and 14% are caused by simultaneous changes in the venous and arterial systems (mixed leg ulcer):
- Venous leg ulcer (Ulcus cruris venosum): in the case of venous weakness or after thrombosis, blood backs up into the legs, which initially leads to water accumulation (edema), and later additionally to hardening of the skin and connective tissue. The backwater continues into the capillaries, the finest blood vessels between arteries and veins. As a result, the blood flow slows down or stops completely, so that the blood can no longer deliver sufficient oxygen and nutrients to the surrounding tissue. Complicating the exchange of substances is the tissue swelling caused by the edema, whereby from the outside the vessels are compressed.
- Arterial leg ulcer (Ulcus cruris arteriosum): In arterial vascular disease, arterial calcification leads to narrowing to complete occlusion of the arteries. This initially affects the small and smallest vessels. Here again results in an undersupply of the surrounding tissue with the possible consequence of an ulcer.
- Other forms: More rarely, the leg ulcer is caused by impaired joint function, for example, of the upper ankle (arthrogenic congestion syndrome), infections (Ulcus infectiosum), blood diseases (Ulcus haematopoeticum), cancer (Ulcus neoplasticum) or by other diseases (eg, ulcerative colitis).
