Venous leg ulcers: Are skin grafts effective?

FPhoto of a patient talking with her doctor (Ryan McVay / Photodisc / Thinkstock)

Different types of skin grafts can be used in the treatment of poorly healing wounds that arise when leg veins have trouble transporting blood from the legs back to the heart. There is a lack of research on most of them. But some studies suggest that bilayer artificial skin made from human cells can improve the likelihood of venous leg ulcers healing within six months.

The likelihood of developing a chronic wound on the lower leg increases with age: about 1 out of 100 older people are affected. The most common form is a venous leg ulcer, which is a poorly healing open wound or sore spot that usually develops right above the ankle.

How do venous leg ulcers develop?

Venous leg ulcers may develop if blood collects in the leg veins and no longer flows back to the heart properly. This condition is referred to as venous insufficiency or chronic venous insufficiency. It may cause swelling in the ankles and make your calves feel tight.

When blood pools in the veins of the lower legs, that puts pressure on the capillaries (the smallest blood vessels) that carry blood to the different layers of skin. This pressure also damages the tissue and prevents it from receiving oxygen, nutrients, immune system cells, and cells needed for wound healing. Over time, this can result in an open wound.

If blood no longer circulates properly, it’s more difficult for wounds to heal too. That’s why it can take months or even years for venous leg ulcers to heal. These kinds of poorly healing ulcers can be very painful and have a major impact on everyday life.

Using skin grafts to treat wounds

For a venous leg ulcer to be able to heal, new skin needs to grow. Skin grafts are used in larger wounds to speed up the healing process. The grafts are either made of skin taken from another part of the person’s body, or artificial skin tissue that is attached to healthy skin at the edge of the wound. The graft and body’s skin then grow together, helping to close the wound.

Skin graft tissue can be taken from humans or animals. But it can also be made from human cells that have been grown in a lab. Or it can be produced using biological engineering that combines skin cells with other materials. If cells are taken from two different layers of skin, it’s known as bilayer artificial skin. All transplants carry the risk of infection.

The effect of skin grafts on wound healing

Researchers from the Cochrane Collaboration (an international research network) wanted to find out whether skin grafts are more effective than standard treatments for venous leg ulcers – and how the various types of grafts compare. They looked for studies that tested whether skin grafts could increase the chances of healing in venous leg ulcers. The researchers found 17 suitable studies involving just over 1,000 people. Most of the studies were small and tested many different types of grafts. This means that only little data is available for each of the skin graft types, so it’s not possible to draw any conclusions about most of the grafts.

Nearly 350 people who all had a poorly healing leg wound took part in two fairly large studies. In both studies, one group had skin grafts with bilayer artificial skin made from human cells, and also used compression bandages. The other group was given simple wound dressings and used compression bandages. The combined results of both studies showed that the wounds healed completely within six months

  • in 40 out of 100 people who had conventional treatment using wound dressings, and
  • in 61 out of 100 people who had a skin graft.

In other words: Compared to conventional treatment, skin grafts helped the wounds to heal more quickly in 21 out of 100 people.

Because these studies only tested bilayer artificial skin grafts made from human cells, and also had some limitations, the researchers concluded that more studies are needed on the effectiveness of skin grafts. There is also not enough research to be able to say anything about the possible side effects of skin grafts in the treatment of chronic venous leg ulcers.