This is best achieved in clean, uncontaminated wounds with free tissue bleeding following debridement. Closure should be performed in layers under no tension. Sometime surgeons tend to push the limit as to how much tension is permissible, and although we may get away with it in a younger, healthy patient, we may not be so fortunate in an older patient. It is important therefore to perform tension-free closure, if it is not possible to close the defect with a skin graft or flap.

In cases where there is extensive soft tissue damage, closure is usually delayed. In other words, after initial wound debridement, the wound is reassessed 36–48 h later at which time further debridement may be necessary prior to providing cover. This gives the tissue enough time to declare its viability.

Split-thickness skin grafts (STSGs) are thinner and therefore can survive on a recipient bed that has less vascularity than that needed by full-thickness skin grafts (FTSGs). An important advantage of STSGs is that they can cover a large area. A disadvantage of STSGs is that they are usually a poor colour and texture match with the surrounding normal tissue and they tend to contract. This contracture can be a particular problem in growing children since, unlike FTSGs, they do not grow with the child. STSGs are also less durable and should be avoided over pressure points if possible. Full-thickness skin grafts (FTSGs) are used for small defects, especially in the hands or face where quality and colour match are important. Most FTSGs are harvested in an elliptical fashion so that the donor site can be closed primarily, usually after some undermining of the edges.

A distinct disadvantage of skin grafts, in general, is that they cannot be used to cover exposed bone, tendon or joint as there is no direct blood supply to the overlying skin graft. These wounds can only be adequately covered by flaps.

A flap is a unit of tissue that can be mobilised based on its blood supply. Since the transferred tissue depends on a blood supply, it is imperative that flap design incorporates a reliable vascular supply. Initially a random pattern flap was developed which involved raising a skin flap with a 1.5:1 or even 2:1 length to width ratio (Fig. 68.3). The flap could be rotated into the adjacent defect. The survival of such flaps depends on the circulation in the random subdermal plexus and a zone of injury confined to the defect. Random pattern flaps because of their relatively poor blood supply are not reliable in contaminated or infected wounds. Better understanding of the blood supply of the skin led to the introduction of axial pattern flaps. These flaps are based on an underlying longitudinal vascular network, resulting in a flap design not limited by the length to width ratio but by the length of the underlying vessels (Fig. 68.4). These flaps are more robust and resistant to infection. Examples of axial pattern flaps include the deltopectoral (internal thoracic vessels), lateral forehead (superficial temporal artery), dorsum of foot (dorsalis pedis artery) and superficial groin flaps based on the superficial circumflex iliac artery.