Chronic venous insufficiency is a term used to describe the changes that can take place in the tissues of the leg, due to longstanding high pressure in the veins. This high pressure in the veins usually occurs because blood flow in the veins is abnormal, secondary to valvular incompetence, causing reflux (reverse flow) in the veins. High venous pressure may also occur if the veins in the legs become blocked, but this is much less common. In many patients varicose veins will also be present in conjunction with chronic venous insufficiency, but this is not always the case. There are many patients with typical changes of chronic venous insufficiency, but no obvious problem with their superficial veins. These patients may have abnormalities in the deeper veins which will only be apparent on ultrasound scans.
The prolonged high pressures in varicose veins appear to lead to low level chronic inflammation in the surrounding tissues and to ultimately produce the clinical changes described below.
Pigmentation - A brown discolouration of the skin can develop in the gaiter area (just above the ankle) and is a typical sign of venous disease. The brown discolouration occurs when blood cells leak out of the blood vessels. Haemoglobin from the red blood cells is broken down into a compound called haemosiderin, which is then permanently deposited in the tissues. This can commonly occur after a significant injury to the leg and will be made worse by an underlying problem in the veins.
Ulceration - In some patients damage to the tissues can become so bad that an area of skin can be lost. When an area of skin is lost the raw area left behind is called an ulcer. Ulcers can vary from being very small to very large. Some patients become very worried when they hear they have an ulcer. Ulcers can certainly be very troublesome, but the term ulcer only means that an area of skin has been lost. It does not have any more serious underlying connotations.
Swelling - Swelling around the ankle, foot and lower leg especially of a mild degree can occur in many patients with venous problems. If it becomes more severe and is only present in one leg, then it can be a sign that investigation and treatment of the venous system is required.
Varicose eczema - When this develops, the skin becomes red, wet and scaly. It can vary from a relatively small localised area with very mild changes, to a situation where the whole of the lower leg is involved and the skin can appear very angry and inflamed.
Mention of an ulcer often concerns patients. An ulcer is simply an area that has lost the covering layer of skin so that the tissues beneath the skin are exposed. This is all that is meant by an ulcer. It does not imply anything about the cause of the ulcer or how it will respond to treatment.
There is an important distinction between an ulcer and a graze on the leg. In the case of a graze only the superficial layers of the skin are lost even though this can be deep enough to cause bleeding. In an ulcer the whole thickness of the skin is lost and there are no skin cells in the defect. This difference has important implications for healing. In the case of a graze healing can take place over the whole graze, as there are still skin cells over the whole area. Healing is quick (5-10 days) because of these cells. In an ulcer the only way skin cells can bridge the ulcer and heal over is for the cells to grow in from the edges. This is a much slower process even in perfect conditions.
Leg ulcers are caused by two main problems in developed countries. The two commonest causes of ulceration are diseases of the veins and diseases of the arteries. As many as 75% of patients have a significant venous component to their leg ulcers. Arterial ulceration and mixed arterio-venous ulcers (ulcers due to a combination of venous and arterial disease) constitute the second major group of leg ulceration patients (14%). Diabetes mellitus can also cause ulceration, but predominantly in the foot. Venous and arterial problems can also occur in patients with diabetes.
Sometimes ulcers can be due to skin cancers, although the majority of ulcers on the legs are not skin cancers. Rarely, a longstanding leg ulcer may develop into a skin cancer, usually a squamous cell carcinoma, commonly known as a Marjolin's ulcer.
Yes, leg ulcers can be treated but the best form of treatment for your leg ulcer will depend on exactly why the ulcer has occurred.
A high proportion of ulcers are caused by problems in the veins. This should be confirmed by clinical assessment and on special investigations. If this is the case then compression treatment should be commenced. It should only be applied after the arteries have been assessed by measuring the ankle-brachial index. This is because if compression is applied and the arteries are badly diseased, this can damage the ulcer and the leg, and make matters worse. It would also be very painful.
Before compression is applied, the leg and the ulcer should be thoroughly cleaned and a simple dry, non-adherent dressing applied to the ulcer itself. The ankle circumference is then measured and the compression system selected. The compression bandage is applied by a trained practitioner, usually a nurse skilled in bandaging techniques. Often a 4-layered bandaging system is used. The first layer consists of a soft wool bandage to protect bony points at the ankle and the shin bone. A crepe bandage is applied as the second layer. The third layer is an elasticated bandage that will apply compression. The final fourth layer applies further compression and keeps all of the bandages in place. Although this sounds quite complicated, it is quite straightforward to apply in practice, by properly trained personnel. These bandages may be left in place for up to 7 days, but should be changed if fluid from the ulcer soaks through the bandages. If possible they are left, as it is thought that each dressing change damages some of the ulcer tissue that is trying to heal.
Some ulcers are mainly arterial even if they have a venous component. This is always the case when the Ankle-Brachial Index is less than 0.5, indicating a severe degree of arterial impairment. In these circumstances compression should never be applied. These ulcers should be managed by examining the arteries in more detail by ultrasound and angiography. Usually patients with these ulcers will require some treatment to improve the blood supply if their ulcer is going to heal.
In some patients the ulcers are caused by a combination of problems in the arteries and the veins. It can sometimes be difficult in these patients to decide the most effective way of managing their ulcer. In general if the Ankle-Brachial Index is greater than 0.5, but less than 0.8, it is often sensible to try modified (lighter) compression as a first option. If this is tolerated and appears to be helping the ulcer to heal, then it should be continued. If it is not tolerated or appears to be unhelpful then it will be important to investigate the arteries in the same way as for arterial ulcers (Humphreys ML, 2007).
In general provided the blood supply to the tissues is good and compression is applied, when appropriate, it hardly matters which dressing is placed onto the ulcer bed. As long as it is clean, dry and non-adherent the ulcer should respond. Many claims are made for different types of dressings, most of which are hard to substantiate. Regular changes of dressing type usually have little value and may actually do harm as patients often develop reactions (dermatitis) to dressings and exudate. A review and meta-analysis of dressings for venous ulcers showed that the type of dressing applied beneath compression was not shown to influence healing (Palfreyman S, Nelson EA, Michaels JA, 2007).
It is perfectly acceptable to clean your leg and ulcer with ordinary tapwater. There is no benefit in using sterile water or saline. If you have a planned visit from the district nurse then, by arrangement, it can be useful to shower and clean the leg, if your are able, prior to the planned visit. Only do this after discussion.
