There are various methods for treating chronic wounds. Before surgical treatment is carried out, conservative therapy should be evaluated and, if necessary, exhausted. This can range from a number of local wound dressings to manual therapies such as compression or lymphatic drainage. In addition, it is important to optimize nutritional status, control diabetes and reduce mechanical stress and friction. Adequate hygiene and sterile techniques can prevent infections.
If non-surgical treatment is not sufficient, it may be necessary to treat the wound surgically. Various techniques are available for wound closure, from simple to more complex methods. If a simple closure technique is not possible, the surgeon can use more complex closure options.
First step: Debridement
The first step in treating a chronic wound is to remove necrotic (dead) and infected tissue from the wound. This is called debridement and consists of the surgical removal of debris from the wound. In certain cases, the surgeon may then decide to allow the wound to heal on its own without additional surgery (open – secondary – wound treatment). This is done by keeping the wound clean and regularly covering it with a special dressing.
In some situations, a so-called vacuum dressing (negative pressure wound therapy) can be applied to the affected area to prepare the wound bed for future surgery or to accelerate secondary wound healing. Depending on the duration of the vacuum treatment, a weekly VAC dressing change may be necessary.
Primary closure
In primary closure, the wound edges are brought together and closed with sutures after the wound bed has been debrided. Primary closure is only possible if the wound edges are not too tight and the wound is safely decontaminated. Depending on the location of the wound and the type of suture material used, stitches may need to be removed.
Skin grafts
If primary closure is not possible, a skin graft can be applied to close the wound. The skin graft can be either a full-thickness skin graft or a split-thickness skin graft. The prerequisite is a clean wound bed with a good blood supply and no complex structures such as bones, tendons, nerves or vessels. The skin used for these wounds is usually taken from the thigh, although other areas such as the abdomen or back are also possible in exceptional cases. A full-thickness skin graft is usually used for smaller wounds in delicate areas where you want to minimize contracture. The skin to be used can be taken from the upper arm, groin, neck area or behind the ear, depending on the target localization. The skin graft is placed over the prepared wound bed and fixed in place with a dressing or vacuum dressing for around 5 days. The area where the split skin was removed usually heals without any problems within about 2 weeks.
Local/stemmed lobes
A flap is an area of healthy tissue that can be detached and mobilized to cover a wound using a special incision and taking into account its blood supply. However, the lifting defect should not require another rag. A flap can contain skin, fat, fascia and/or muscle. It can be classified as a local flap (flap and wound are close to each other) or a pedicled flap (skin flap and wound are further apart). In some cases, the skin may need to be stretched beforehand in order to close the wound completely: an implant known as a tissue expander is placed under the skin and regularly filled with saline until the desired skin expansion is achieved, after which the stretched skin and underlying tissue are transferred into the wound to cover it. Depending on the type of flap used, regular observation of the flap may be necessary after the operation in order to detect complications at an early stage.
Free tissue transfer / free flap
Free tissue transfer using a free flap is generally reserved for more complex wounds where a local flap is not available or too small to cover a larger wound, or where there are important structures underneath. Free flaps can consist of different types of tissue, including skin, fat, blood vessels, muscle, bone / cartilage and / or nerves. A free flap consists of transferring tissue and its blood supply from one part of the body to another by detaching the tissue and blood vessels from their original location and reattaching the tissue and its blood supply to another location. The blood vessels (approx. 1-2 mm thick) are detached and sutured back together using a microscope. After the operation, the flap is monitored regularly and intensively for the first few days to check that there is sufficient blood flow to the flap and to intervene at an early stage if complications arise. Complications of free flap surgery can include loss of blood supply to the flap, which can lead to necrosis (death) of the flap or parts of it. If the problem is detected early, it may be possible to correct problems with the blood supply to the free flap. For this reason, the blood supply to the flap is monitored at regular intervals during the first 5 days after the operation.