Open Leg

What is a leg ulcer?

An open leg is a slow-healing wound (formerly also called an ulcer) on the lower leg or foot. In medical terms, it is also known as an ulcus cruris or simply an ulcer. Like pressure ulcers (decubitus) and diabetic foot ulcers (malum perforans), it is classified as a chronic wound. They are characterized by the fact that they have been present for at least four weeks, and despite proper wound care, there are no signs of healing. Normally, a wound that has not been sutured surgically will begin to heal on its own within two to three weeks.

Most often, a leg ulcer is caused by circulatory problems in the veins and/or arteries. There are various diseases associated with reduced blood flow—and thus a reduced supply of oxygen and nutrients to tissues. Examples include chronic venous diseases resulting from a history of deep vein thrombosis in the legs or untreated varicose veins, or peripheral arterial disease (PAD). Peripheral arterial disease (PAD) is exacerbated by cardiovascular risk factors (namely: smoking,diabetes, lipid metabolism disorders, and high blood pressure).

The treatment of a leg ulcer depends largely on the cause. It must not be limited merely to selecting the optimal bandage. The underlying causes must be identified and treated. Otherwise, the open leg will keep coming back. There are various treatment options that promote wound healing and help heal leg ulcers.

Open Leg Wound – Prevalence and Age

Chronic wounds on the lower leg and foot are relatively common. Large-scale studies have shown that approximately one percent of the population develops a leg ulcer at some point in their lives. As people age, the risk of ulcers increases because certain diseases of the arteries and veins become more common. For example, the risk of developing a leg ulcer among people over the age of 80 is already as high as four percent.

Leg Ulcers: Causes and Risk Factors

An open leg wound can have one or more different causes. As a rule, circulatory disorders affecting the veins and/or arteries are involved. Experts distinguish between different forms of leg ulcers based on their underlying causes.

Venous leg ulcer (ulcus cruris venosum, venous ulcer)

The cause of venous leg ulcers is chronic venous insufficiency. In medical terms, it is also known as chronic venous disease (CVD), or, as it was formerly called, chronic venous insufficiency (CVI). In this condition, the veins that are supposed to carry blood back up from the legs to the heart are diseased. When venous outflow is obstructed, pressure on the tissue and small blood vessels increases. The skin on the lower legs becomes hard and receives less blood flow—which can lead to an open leg ulcer. About 50 percent of lower-leg ulcers are caused by a central venous catheter. In about half of the cases, the underlying cause is a previous episode of deep vein thrombosis in the leg, and in the other half, varicose veins associated with chronic venous disease.

Arterial Leg Ulcer (Ulcus cruris arteriosum, arterial ulcer)

In this case, the leg ulcer is caused by hardening of the arteries (atherosclerosis) in the legs (peripheral arterial disease, see above). As a result of years of untreated cardiovascular risk factors (see above), the arteries that carry blood and oxygen from the heart to the organs and legs become increasingly narrowed on the inside. Some of those affected experience the lack of oxygen as pain in their feet, calves, or thighs when walking and therefore have to stop frequently (PAD). However, some people immediately develop rest pain in their feet and toes when lying down, which subsides only when they let their legs hang down, or chronic sores on the lower leg or foot (arterial leg ulcer). Approximately 10 percent of all patients with a leg ulcer have an arterial ulcer.

Mixed leg ulcer (veno-arterial ulcer): Venous ulcer and peripheral arterial disease (PAD)

Mixed venous-arterial ulcers account for approximately 20 percent of all chronic lower-leg wounds. This is a venous ulcer (see above) in one leg, which is also affected by PAD (see above). The treatment must (A) PAD and (B) consider chronic venous disease as a cause.

Open leg wounds caused by conditions other than chronic venous disease and/or peripheral arterial disease (PAD)

Approximately 20 percent of leg ulcers are caused by other factors (that is, not chronic venous disease and/or peripheral arterial disease).

Other causes of leg ulcers:

• Severe skin infections, which are more common in cases of malnutrition (e.g., due to alcoholism or social isolation in older adults): Malnourished patients in particular, but also those who must take immunosuppressive medications—for example, following a kidney transplant—are at risk of aggressive skin infections, which often originate from an inflamed hair follicle or a minor wound, and can then spread like wildfire across the skin (erysipelas) and lead to extensive infectious wounds (ecthyma).
• Abrasions of very thin skin (lacerations) and extensive bruising on very thin skin: Older adults may develop very thin skin, particularly on the arms and legs (skin atrophy, dermatoporosis). Even with minor contact or friction, you are at risk of large areas of skin abrasion or the development of extensive bruising (the latter especially if you are taking blood-thinning medication).
• Severe inflammatory skin diseases: A typical example is pyoderma gangraenosum, in which the white blood cells known as neutrophils are overactive. Typically, minor skin injuries result in extensive superficial wounds with a pus-filled rim that quickly spread into the surrounding healthy skin. The pus does not contain any bacteria; rather, it is the result of an excessive immune response. Those affected are also prone to inflammatory bowel diseases (ulcerative colitis, Crohn’s disease) or inflammatory joint conditions (rheumatoid arthritis).
• Severe vascular inflammation caused by an abnormal immune response (vasculitis with skin damage): Although also relatively rare, severe inflammatory processes in the smaller blood vessels of the skin (vasculitis) can lead to circulatory disorders and oxygen deprivation in the affected area, which can result in large, deep skin wounds that heal very poorly.
• Malignant skin tumors: A small fraction—perhaps two percent—of all chronic lower-leg wounds result from undiagnosed skin cancer, such as squamous cell carcinoma or basal cell carcinoma (two types of white skin cancer).

Symptoms: A leg ulcer can cause a wide variety of symptoms

The symptoms of a leg ulcer depend on the underlying causes of the wound—venous, arterial, a combination of both, or other factors.

Venous Ulcer (Ulcus cruris venosum) – Symptoms

Typically, a venous ulcer occurs on the inner side of the lower leg, within an area of brown-discolored skin above the inner ankle. The following symptoms indicate chronic venous disease, which can lead to the development of a venous ulcer:

• Swelling in the lower legs and ankles
• Pronounced varicose veins
• Skin inflammation with scaling, and especially brown, hard skin on the inner side of the lower third of the lower leg

Arterial Ulcer (Ulcus cruris arteriosum) – Symptoms

Arterial ulcers are more commonly found above the outer ankle or along the edge of the shinbone. It’s usually very painful. However, advanced PAD (see above) can also cause slow-healing wounds on the top of the foot and on the toes. Leg pain—initially only during movement and physical activity, and later also at rest; the pain worsens when you elevate your legs (unlike with venous leg ulcers)

• Sometimes, those affected experience pain in the foot, calf, or thigh before or while walking, as a result of the muscles’ lack of oxygen during physical exertion.
• Arterial wounds are often black in the center or at the edges (necrosis)

Mixed Venous-Arterial Ulcer (Ulcus cruris mixtum) – Symptoms

Patients with a mixed venous-arterial ulcer have the same symptoms as those with a venous ulcer.

Diagnosis: Leg Ulcer

When diagnosing an open leg ulcer, the ABCDE rule—proposed by the Chronic Wound Initiative (ICW)—can be helpful. The letters ABDCE stand for the following:

A: Medical History

When you are diagnosed with a non-healing leg wound, you will be asked a few questions about your medical history. This is because, as a rule, if a wound fails to heal, the underlying cause is usually another medical condition. For example, we are interested in the following questions:

• What symptoms have you noticed in yourself?
• How severe are the symptoms?
• Are there situations in which the symptoms get worse or improve?
• How long has the open wound been there?
• Have you ever had wounds in the past that were difficult to heal?
• Do you suffer from venous disorders? Have you ever had a deep vein thrombosis in your leg or a pulmonary embolism? Do you have large varicose veins, or have you had varicose veins removed?
• Do you have a diagnosed case of peripheral arterial disease (PAD)? Have you ever had a procedure with a balloon catheter or bypass surgery on your leg?
• What underlying medical conditions do you have? Do you have high blood pressure or diabetes? Do you smoke? Do you know that you have high blood lipid levels? Do you have heart disease, lung disease, kidney disease, or any other significant medical conditions?
• How tall and how much do you weigh?
• Are you taking any medications? If so: Which ones, and since when?

Based on your answers, we can make an initial assessment of the possible causes of the leg ulcer and order further tests.

B: Bacteria

If a bacterial infection is suspected, or if it is necessary to determine whether the wound is colonized by antibiotic-resistant bacteria, the treatment team takes a swab and sends it to the lab for testing.

C: Clinical Examination

We assess the wound based on the following criteria:

• Where exactly on the lower leg or foot is it located?
• How large and deep is it, and what is its predominant color?
• What do the edges of the wound and the surrounding skin look like?
• Does it have a noticeable odor?
• Is the wound oozing and leaking fluid? If so, what is it like?
• Does it cause pain, either on its own or when touched?

Based on the appearance of the wound, initial decisions regarding further evaluation and treatment can be made.

D: Blood circulation

The treatment team examines the veins and arteries to gather information about blood flow throughout the leg and in the area around the wound. The veins are examined using specialized equipment, specifically color-coded ultrasound (duplex ultrasound). The arteries are first examined using a blood pressure cuff on the ankle and a small Doppler ultrasound probe. If necessary, this is followed by pressure wave recordings using cuffs (oscillography), a duplex ultrasound examination, and finally X-ray angiography.

Leg Ulcers: Prevention, Early Detection, Prognosis

The causes of a leg ulcer are often related to circulatory problems. The condition affects the veins, arteries, or both types of blood vessels. There are several known risk factors that contribute to venous or arterial diseases. And by addressing these factors—which are sometimes related to lifestyle—you can take steps to prevent a leg ulcer. Examples include getting enough exercise, eating a healthy diet, maintaining a normal weight, and not smoking.

In addition, be sure to have any existing medical conditions—such as high blood pressure, diabetes mellitus, or lipid metabolism disorders—properly treated by a doctor. A healthy lifestyle also has a positive effect on these diseases.

As a general rule, if you have any symptoms, always see your doctor as soon as possible. This allows for the early detection of underlying conditions such as varicose veins, venous insufficiency, or peripheral arterial disease. Afterward, have the condition monitored through regular checkups. Even a leg ulcer can be diagnosed and treated in a timely manner this way.

Course and Prognosis of an Open Leg Wound

The course and prognosis depend on the cause, as well as on the severity and extent of the leg ulcer. In addition, the open leg—but above all, the underlying causes of the ulcer—must be treated consistently. You, too, need to actively participate in the therapy.

In most cases, it takes about three to six months for an open leg wound to heal—sometimes even longer. Relapses are also not uncommon. Thus, depending on the severity, about 10 to 30 percent of people with a venous ulcer experience a relapse after one year. Patients with combined arterial and venous circulatory disorders are also at risk of a recurrent leg ulcer. People who consistently wear compression stockings during the day can effectively prevent such relapses.