Leg Ulcers

An ulcer is defined as a break in the skin with loss of epidermis or also dermis. Leg ulcers have a major impact on quality of life causing social restriction and pain, costing the UK NHS £400 million each year. There are many causes of leg ulcers (Table 45.1).

Venous Hypertension and Pathogenesis of Venous Ulcers

The pressure in the veins in the lower leg depends on the height of blood directly above pressing down: this is usually 0–20 mmHg. Disease of the veins, immobility and obesity results in the valves in the large veins in the leg not working properly (incompetent) and so the pressure rises above 20 mmHg (venous hypertension). This high pressure results in leakage of fluid (oedema) and fibrin from the veins into the dermis. Fibrin cuffs form around the small veins in the dermis, causing venous insufficiency and ulceration.

Venous Eczema (Stasis Dermatitis, Gravitational Eczema, Varicose Eczema) (Figure 45.1)

Occurs on the lower legs and is itchy. There is mild scaling with redness and oozing. The hyperpigmentation looks like melanin but is caused by dermal haemosiderin from red blood cells.

Treatment: emollients and low potency topical steroids.

Atrophie Blanche

Small white atrophic lesions typically near a painful lower leg ulcer, with red dots (large capillaries) visible. May suggest other systemic inflammatory disease (e.g. SLE) (Figure 45.2).

Lipodermatosclerosis

A hard painful ‘wooden feeling’ area around the lower leg, with overlying redness and palpable edge (Figure 45.3). The leg shape may look like an upside down cola or wine bottle. It is caused by long-standing venous hypertension, chronic inflammation and fibrin in dermis and underlying fat. Often confused with cellulitis, but this is inflammation without infection. There is a high risk of ulceration. Compression may help long term but is ‘too late’.