Skin grafts are commonly used for ulcers, burns, wound dehiscence, amputation, and surgical excision. The best types of skin graft are those that come directly from the patient. These grafts are known as autografts, auto meaning self. These grafts are safest to use and heal faster than other types of grafts. The only pitfall with using an autograft is that a second wound is created when harvesting the graft from a different site.
There are split thickness grafts and full thickness grafts. Split thickness grafts contains the epidermis and dermis where as a full thickness graft contains more layers of the skin. Split thickness grafts are more commonly used because they are less likely to form a contracture over time. The thickness of a skin graft depends on what area of the body is harvested. For example the skin of the outside of the thigh is thicker than the inside of the thigh.
Types of Split Thickness Grafts
Thin: 0.008-0.011 inches
Intermediate: 0.012-0.014 inches
Thick: 0.015-0.024 inches
Graft healing occurs in 4 phases:
- Plasmatic Stage (24-48hrs): the graft adheres to the bed
- Inosculation (end of 48hrs): vascular network forms connecting the vessels to the new graft to restore blood flow. The graft will turn a pink hue color
- Capillary Ingrowth: capillary network penetrates into the graft
- Maturation: lymphatic channels and nerves develop
Most grafts fail within the first 72 hours as a result of inadequate adherence that disrupts the blood supply from establishing. A hematoma and seroma can separate the graft from the bed and disrupt ingrowing vessels. It is important to have a compression dressing applied and to leave it intact for a week and limit motion to the area. Infection can also result in graft failure.
For more information on grafts and how they are harvested come see us at Foot & Ankle Doctors, Inc