Plastic surgery is the craft of moving skin and soft tissues to repair damage or to improve appearance and function.

The skin provides a crucial function preventing excess fluid from leaving the body and infection from entering the body. Soft tissues are also necessary to provide a substrate for healthy skin. When skin and soft tissues are lost due to trauma or because diseased tissue has been excised, it may not be possible to simply close the defect. Exposed bone and ligaments will become infected if they are not covered, while soft tissues left to heal of their own accord may leave ugly scars which hamper normal function when they contract as part of the healing process.

• Superficial defects (grazes and partial thickness burns). In these cases the skin heals from nests of epithelial cells growing out from hair follicles where they were protected from the original trauma. Healing is reasonable providing the damaged area is cleaned and kept free of infection.
  
• Full thickness defects (complete loss of skin with intact soft tissues beneath). Surgeons use the skin’s ability to heal partial thickness defects to harvest epithelial skin which can then be used as a split skin graft to cover a full thickness defect. The graft can be meshed to cover a larger area and will stimulate rapid healing without contracture, although the scar is not attractive and the resistance of the graft area to abrasion is poor. For very large defects it is now possible to culture epithelial cells from the patient and use these to ‘seed’ the growth of an epithelial cover.
  
• Complete soft tissue loss (exposed bone). Skin and underlying vascularised muscle will be needed to cover these defects. If it is possible to rotate nearby skin and muscle to cover the defect while maintaining its blood supply, then this pedicle graft will be the best option. Normally it is possible to dissect out an area of skin and underlying muscle from a part of the body where it can be spared. This vascularised graft is then plumbed into its new site, using microsurgery to connect its arterial supply and venous drainage to the local blood supply.