This article has multiple issues. Please help improve it or discuss these issues on the talk page . (Learn how and when to remove these messages)
|
Skin grafting | |
---|---|
ICD-9-CM | 86.6 |
MedlinePlus | 002982 |
Skin grafting, a type of graft surgery, involves the transplantation of skin without a defined circulation. The transplanted tissue is called a skin graft. [1]
Surgeons may use skin grafting to treat:
Skin grafting often takes place after serious injuries when some of the body's skin is damaged. Surgical removal (excision or debridement) of the damaged skin is followed by skin grafting. The grafting serves two purposes: reducing the course of treatment needed (and time in the hospital), and improving the function and appearance of the area of the body which receives the skin graft.
There are two types of skin grafts:
A full-thickness skin graft is more risky, in terms of the body accepting the skin, yet it leaves only a scar line on the donor section, similar to a Cesarean-section scar. In the case of full-thickness skin grafts, the donor section will often heal much more quickly than the injury and causes less pain than a partial-thickness skin graft. A partial thickness donor site must heal by re-epithelialization which can be painful and take an extensive length of time.
Two layers of skin created from animal sources has been found to be useful in venous leg ulcers. [3]
Grafts can be classified by their thickness, the source, and the purpose. By source:
Allografts, xenografts, and prosthetic grafts are usually used as temporary skin substitutes, that is a wound dressing for preventing infection and fluid loss. They will eventually need to be removed as the body starts to reject the foreign material. Autologous grafts and some forms of treated allografts can be left on permanently without rejection. [5] Genetically modified pigs can produce allograft-equivalent skin material, [6] and tilapia skin is used as an experimental cheap xenograft in places where porcine skin is unavailable and in veterinary medicine. [7] [8]
By thickness:
When grafts are taken from other animals, they are known as heterografts or xenografts. By definition, they are temporary biologic dressings which the body will reject within days to a few weeks. They are useful in reducing the bacterial concentration of an open wound, as well as reducing fluid loss.
For more extensive tissue loss, a full-thickness skin graft, which includes the entire thickness of the skin, may be necessary. This is often performed for defects of the face and hand where contraction of the graft should be minimized. The general rule is that the thicker the graft, the less the contraction and deformity.
Cell cultured epithelial autograft (CEA) procedures take skin cells from the person needing the graft to grow new skin cells in sheets in a laboratory; because the cells are taken from the person, that person's immune system will not reject them. However, because these sheets are very thin (only a few cell layers thick) they do not stand up to trauma, and the "take" is often less than 100%. Newer grafting procedures combine CEA with a dermal matrix for more support.[ clarify ]Research is investigating the possibilities of combining CEA and a dermal matrix in one product.
Experimental procedures are being tested for burn victims using stem cells in solution which are applied to the burned area using a skin cell gun. Recent[ when? ] advances have been successful in applying the cells without damage.[ citation needed ]
In order to remove the thin and well preserved skin slices and strips from the donor, surgeons use a special surgical instrument called a dermatome. This usually produces a split-thickness skin graft, which contains the epidermis with only a portion of the dermis. The dermis left behind at the donor site contains hair follicles and sebaceous glands, both of which contain epidermal cells which gradually proliferate out to form a new layer of epidermis. The donor site may be extremely painful and vulnerable to infection. There are several ways to treat donor site pain. These include subcutaneous anesthetic agents, topical anesthetic agents, and certain types of wound dressings. [10]
The graft is carefully spread on the bare area to be covered. It is held in place by a few small stitches or surgical staples. The healing process for skin grafts typically occurs in three stages: plasmatic imbibition, capillary inosculation, and neovascularization.
During the first 24 hours, the graft is initially nourished by a process called plasmatic imbibition in which the graft "drinks plasma" (i.e., absorbs nutrients from the underlying recipient bed).
Between 2–3 days, new blood vessels begin growing from the recipient area into the transplanted skin in a process called capillary inosculation.
Between 4–7 days, neovascularization occurs in which new blood vessels form between the graft and the recipient tissues.
To prevent the accumulation of fluid under the graft which can prevent its attachment and revascularization, the graft is frequently meshed by making lengthwise rows of short, interrupted cuts, each a few millimeters long, with each row offset by half a cut length like bricks in a wall. In addition to allowing for drainage, this allows the graft to both stretch and cover a larger area as well as to more closely approximate the contours of the recipient area. However, it results in a rather pebbled appearance upon healing that may ultimately look less aesthetically pleasing. [11]
An increasingly common aid to both pre-operative wound maintenance and post-operative graft healing is the use of negative pressure wound therapy (NPWT). This system works by placing a section of foam cut to size over the wound, then laying a perforated tube onto the foam. The arrangement is then secured with bandages. A vacuum unit then creates negative pressure, sealing the edges of the wound to the foam, and drawing out excess blood and fluids. This process typically helps to maintain cleanliness in the graft site, promotes the development of new blood vessels, and increases the chances of the graft successfully taking. NPWT can also be used between debridement and graft operations to assist an infected wound in remaining clean for a period of time before new skin is applied. Skin grafting can also be seen as a skin transplant.[ medical citation needed ]
This is based upon the principle of mobilizing a full segment of skin from an area to the site needing tissue replacement. The flaps are triangularly shaped opposite each other. It can be used in direct excision and closure of a contracted scar to produce a better looking and healing scar. It helps to elongate and break up a linear scar. It also gives a good result in the release of linear contractures. [12] [13] [14] [15] Z-plasty is of paramount importance to the plastic surgeon and a frequently used method in both single multiple forms. [16]
Risks for the skin graft surgery are:
Rejection may occur in xenografts. To prevent this, the person receiving the graft usually must be treated with long-term immunosuppressant drugs.
Most skin grafts are successful, but in some cases grafts do not heal well and may require repeat grafting. The graft should also be monitored for good circulation.
Recovery time from skin grafting can be long. Graft recipients wear compression garments for several months and are at risk for depression and anxiety consequent to long-term pain and loss of function. [17]
Skin grafting, in more rudimentary forms, has been practiced since ancient times. The Ebers Papyrus of ancient Egypt contains a brief treatise on xenografting. [18] Around 500 years later, members of the Hindu Kamma caste are described as performing skin grafts which included the usage of subcutaneous fat. [19] The 2nd century AD Greek philosopher Celsus is also known to have developed a method to reconstruct the foreskins of Jewish men using skin grafts, as circumcision was considered barbaric in Greek and Roman society. [20]
More modern uses of skin grafting were described in the mid-to-late 19th century, including Reverdin's use of the pinch graft in 1869; Ollier's and Thiersch's uses of the split-thickness graft in 1872 and 1886, respectively; and Wolfe's and Krause's use of the full-thickness graft in 1875 and 1893, respectively. John Harvey Girdner demonstrated skin graft transplant from a deceased donor in 1880. [21] Today, skin grafting is commonly used in dermatologic surgery. [22] Recently Reverdin's technique is used but with very small (less than 3 mm diameter). Such small wounds heal in a short time without scars. This technique is called SkinDot. [23]
There are alternatives to skin grafting including skin substitutes using cells from patients, [24] skin from other animals, such as pigs, known as Xenograft and medical devices that help to close large wounds. Xenograft was originally known as "zoografting." Other animals that can be used include dogs, rabbits, frogs, and cats, with the greatest success achieved with porcine skin. [12] [13] Other skin substitutes include Allograft, Biobrane, TransCyte, Integra, AlloDerm, Cultured epithelial autografts (CEA).
There are medical devices that help close large wounds. The device uses skin anchors that are attached to healthy skin. An adjustable tension controller then exerts a constant pulling tension on sutures looped around the skin anchors. The device gradually closes the wound over time. [25]
“Microcolumn grafting” is a new grafting method being researched that uses needles to take autologous skin biopsies from the patient & implant them in the wound site. [26] [27] [28]
A scar is an area of fibrous tissue that replaces normal skin after an injury. Scars result from the biological process of wound repair in the skin, as well as in other organs, and tissues of the body. Thus, scarring is a natural part of the healing process. With the exception of very minor lesions, every wound results in some degree of scarring. An exception to this are animals with complete regeneration, which regrow tissue without scar formation.
Rhinoplasty, commonly called nose job, medically called nasal reconstruction, is a plastic surgery procedure for altering and reconstructing the nose. There are two types of plastic surgery used – reconstructive surgery that restores the form and functions of the nose and cosmetic surgery that changes the appearance of the nose. Reconstructive surgery seeks to resolve nasal injuries caused by various traumas including blunt, and penetrating trauma and trauma caused by blast injury. Reconstructive surgery can also treat birth defects, breathing problems, and failed primary rhinoplasties. Rhinoplasty may remove a bump, narrow nostril width, change the angle between the nose and the mouth, or address injuries, birth defects, or other problems that affect breathing, such as a deviated nasal septum or a sinus condition. Surgery only on the septum is called a septoplasty.
Tissue expansion is a technique used by plastic, maxillofacial and reconstructive surgeons to cause the body to grow additional skin, bone, or other tissues. Other biological phenomena such as tissue inflammation can also be considered expansion.
Grafting refers to a surgical procedure to move tissue from one site to another on the body, or from another creature, without bringing its own blood supply with it. Instead, a new blood supply grows in after it is placed. A similar technique where tissue is transferred with the blood supply intact is called a flap. In some instances, a graft can be an artificially manufactured device. Examples of this are a tube to carry blood flow across a defect or from an artery to a vein for use in hemodialysis.
Allotransplant is the transplantation of cells, tissues, or organs to a recipient from a genetically non-identical donor of the same species. The transplant is called an allograft, allogeneic transplant, or homograft. Most human tissue and organ transplants are allografts.
Bone grafting is a surgical procedure that replaces missing bone in order to repair bone fractures that are extremely complex, pose a significant health risk to the patient, or fail to heal properly. Some small or acute fractures can be cured without bone grafting, but the risk is greater for large fractures like compound fractures.
Hair transplantation is a surgical technique that removes hair follicles from one part of the body, called the 'donor site', to a bald or balding part of the body known as the 'recipient site'. The technique is primarily used to treat male pattern baldness. In this minimally invasive procedure, grafts containing hair follicles that are genetically resistant to balding are transplanted to the bald scalp.
Follicular unit extraction Performed under local anaesthetic, FUE procedure involves the harvesting of individual hair follicles from the donor site at the back of the head using a tiny 0.8 - 1mm punch which creates an incision around the top of the follicle and extracts them directly from the scalp. The FUE method allows the surgeon to complete the procedure without leaving any linear scarring. It is one of two primary methods of obtaining hair follicles, naturally occurring groups of one to four hairs, for hair transplantation. The other method is called strip harvesting. In 2018, Mejia published the updated guidelines adopted by the International Society of Hair Restoration Surgery. This name change came about to accurately describe the procedure which involves surgically cutting or incising a full thickness hair follicle skin graft with a circular scalpel, punch or motorized drill and subsequently carefully extracting it from the scalp to be placed in the donor balding scalp. Due to the new developments of incision punches and devices and a variety of different extraction techniques, it was necessary to more accurately define the procedure. Additionally, many places were incorrectly marketing the extraction procedure as a simple plucking of hairs and deceiving the public.
Neuroregeneration is the regrowth or repair of nervous tissues, cells or cell products. Neuroregenerative mechanisms may include generation of new neurons, glia, axons, myelin, or synapses. Neuroregeneration differs between the peripheral nervous system (PNS) and the central nervous system (CNS) by the functional mechanisms involved, especially in the extent and speed of repair. When an axon is damaged, the distal segment undergoes Wallerian degeneration, losing its myelin sheath. The proximal segment can either die by apoptosis or undergo the chromatolytic reaction, which is an attempt at repair. In the CNS, synaptic stripping occurs as glial foot processes invade the dead synapse.
In dentistry, the subepithelial connective tissue graft is an oral and maxillofacial surgical procedure first described by Alan Edel in 1974. Currently, it is generally used to obtain root coverage following gingival recession, which was a later development by Burt Langer in the early 1980s.
Transplantable organs and tissues may refer to both organs and tissues that are relatively often transplanted, as well as organs and tissues which are relatively seldom transplanted. In addition to this it may also refer to possible-transplants which are still in the experimental stage.
Suction blistering is a technique used in dermatology to treat chronic wounds, such as non-healing leg ulcers. When a wound is not healing properly, an autologous skin graft is the best option, to prevent rejection of the tissue. Since autologous transplantation cannot always be performed, a substitute has to be used, such as cultured skin. However, this technique is costly and time-consuming. Other uses of suction blisters are to provide transplantation donor tissue for vitiligo research. Suction blisters are often used in tissue serum research in the pharmaceutical and cosmetic research fields. Many research citations are published worldwide that support these uses.
Artificial skin is a collagen scaffold that induces regeneration of skin in mammals such as humans. The term was used in the late 1970s and early 1980s to describe a new treatment for massive burns. It was later discovered that treatment of deep skin wounds in adult animals and humans with this scaffold induces regeneration of the dermis. It has been developed commercially under the name Integra and is used in massively burned patients, during plastic surgery of the skin, and in treatment of chronic skin wounds.
Acellular dermis is a type of biomaterial derived from processing human or animal tissues to remove cells and retain portions of the extracellular matrix (ECM). These materials are typically cell-free, distinguishing them from classical allografts and xenografts, can be integrated or incorporated into the body, and have been FDA approved for human use for more than 10 years in a wide range of clinical indications.
The dermal equivalent, also known as dermal replacement or neodermis, is an in vitro model of the dermal layer of skin. There is no specific way of forming a dermal equivalent, however the first dermal equivalent was constructed by seeding dermal fibroblasts into a collagen gel. This gel may then be allowed to contract as a model of wound contraction. This collagen gel contraction assay may be used to screen for treatments which promote or inhibit contraction and thus affect the development of a scar. Other cell types may be incorporated into the dermal equivalent to increase the complexity of the model. For example, keratinocytes may be seeded on the surface to create a skin equivalent, or macrophages may be incorporated to model the inflammatory phase of wound healing.
Flap surgery is a technique in plastic and reconstructive surgery where tissue with an intact blood supply is lifted from a donor site and moved to a recipient site. Flaps are distinct from grafts, which do not have an intact blood supply and relies on the growth of new blood vessels. Flaps are done to fill a defect such as a wound resulting from injury or surgery when the remaining tissue is unable to support a graft, wound contraction is to be avoided or to rebuild more complex anatomic structures like breasts or jaws. Flaps may also carry with them tissues such as muscle and bone that may be useful in the ultimate reconstruction.
Scalp reconstruction is a surgical procedure for people with scalp defects. Scalp defects may be partial or full thickness and can be congenital or acquired. Because not all layers of the scalp are elastic and the scalp has a convex shape, the use of primary closure is limited. Sometimes the easiest way of closing the wound may not be the ideal or best way. The choice for a reconstruction depends on multiple factors, such as the defect itself, the patient characteristics and surgeon preference.
Fat transfer, also known as fat graft, lipomodelling, or fat injections, is a surgical process in which a person's own fat is transferred from one area of the body to another area. The major aim of this procedure is to improve or augment the area that has irregularities and grooves. Carried out under either general anesthesia or local anesthesia, the technique involves 3 main stages: fat harvesting, fat processing and fat injection.
Dermatologic surgical procedures are treatments aimed at managing a wide range of medically necessary and cosmetic conditions, with a long history dating back to ancient times.
Tissue transplantation is a surgical procedure involving the removal of tissue from a donor site or the creation of new tissue, followed by tissue transfer to the recipient site. The aim of tissue transplantation is to repair or replace tissues that are missing, damaged, or diseased, thereby improving patients' survival, functionality and quality of life.