Skin grafting, a type of
graft surgery, involves the
transplantation of
skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...
. The transplanted
tissue is called a skin graft.
Surgeons may use skin grafting to treat:
* extensive
wound
A wound is a rapid onset of injury that involves laceration, lacerated or puncture wound, punctured skin (an ''open'' wound), or a bruise, contusion (a ''closed'' wound) from blunt force physical trauma, trauma or compression. In pathology, a '' ...
ing or
trauma
Trauma most often refers to:
* Major trauma, in physical medicine, severe physical injury caused by an external source
* Psychological trauma, a type of damage to the psyche that occurs as a result of a severely distressing event
*Traumatic i ...
*
burns Burns may refer to:
* Burn, an injury (plural)
People:
* Burns (surname), includes list of people and characters
Business:
* Burns London, a British guitar maker
Places:
;In the United States
* Burns, Colorado, unincorporated community in Eagle ...
* areas of extensive skin loss due to infection such as
necrotizing fasciitis
Necrotizing fasciitis (NF), also known as flesh-eating disease, is a bacterial infection that results in the death of parts of the body's soft tissue. It is a severe disease of sudden onset that spreads rapidly. Symptoms usually include red or p ...
or
purpura fulminans
Purpura fulminans is an acute, often fatal, thrombotic disorder which manifests as blood spots, bruising and discolouration of the skin resulting from coagulation in small blood vessels within the skin and rapidly leads to skin necrosis and disse ...
* specific surgeries that may require skin grafts for healing to occur - most commonly removal of
skin cancer
Skin cancers are cancers that arise from the skin. They are due to the development of abnormal cells that have the ability to invade or spread to other parts of the body. There are three main types of skin cancers: basal-cell skin cancer (BCC) ...
s
Skin grafting often takes place after serious injuries when some of the body's skin is damaged. Surgical removal (excision or
debridement
Debridement is the medical removal of dead, damaged, or infected tissue to improve the healing potential of the remaining healthy tissue. Removal may be surgical, mechanical, chemical, autolytic (self-digestion), and by maggot therapy.
In p ...
) 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:
* The more common type involves removing a thin layer of skin from a healthy part of the body (the donor section) - like peeling a potato.
* A full-thickness skin graft involves pinching and cutting skin away from the donor section.
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.
Medical uses
Two layers of skin created from animal sources has been found to be useful in
venous leg ulcer
Venous ulcer is defined by the American Venous Forum as "a full-thickness defect of skin, most frequently in the ankle region, that fails to heal spontaneously and is sustained by chronic venous disease, based on venous duplex ultrasound testing." ...
s.
Classification
Grafts can be classified by their thickness, the source, and the purpose. By source:
* Autologous: The donor skin is taken from a different site on the same individual's body (also known as an ''autograft'').
* Isogeneic: The donor and recipient individuals are genetically identical (e.g.,
monozygotic twins
Twins are two offspring produced by the same pregnancy.MedicineNet > Definition of TwinLast Editorial Review: 19 June 2000 Twins can be either ''monozygotic'' ('identical'), meaning that they develop from one zygote, which splits and forms two em ...
, animals of a single inbred strain; ''isograft'' or ''syngraft'').
* Allogeneic: The donor and recipient are of the same species (human→human, dog→dog; ''allograft'').
* Xenogeneic: The donor and recipient are of different species (e.g., bovine cartilage; pig skin; ''
xenograft
Xenotransplantation (''xenos-'' from the Greek meaning "foreign" or strange), or heterologous transplant, is the transplantation of living cells, tissues or organs from one species to another. Such cells, tissues or organs are called xenograft ...
'' or ''heterograft'').
* Prosthetic: Lost tissue is replaced with synthetic materials such as metal, plastic, or ceramic (''prosthetic implants'').
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 it. Autologous grafts and some forms of treated allografts can be left on permanently without rejection. Genetically modified pigs can produce allograft-equivalent skin material, and
tilapia
Tilapia ( ) is the common name for nearly a hundred species of cichlid fish from the coelotilapine, coptodonine, heterotilapine, oreochromine, pelmatolapiine, and tilapiine tribes (formerly all were "Tilapiini"), with the economically most ...
skin is used as an experimental cheap xenograft in places where porcine skin is unavailable and in veterinary medicine.
By thickness:
;Split-thickness
:A split-thickness skin graft (STSG) includes the
epidermis
The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and hypodermis. The epidermis layer provides a barrier to infection from environmental pathogens and regulates the amount of water rele ...
and part of the
dermis
The dermis or corium is a layer of skin between the epidermis (with which it makes up the cutis) and subcutaneous tissues, that primarily consists of dense irregular connective tissue and cushions the body from stress and strain. It is divided i ...
. Its thickness depends on the donor site and the needs of the person receiving the graft. It can be processed through a skin mesher which makes apertures onto the graft, allowing it to expand up to nine times its size. Split-thickness grafts are frequently used as they can cover large areas and the rate of autorejection is low. The same site can be harvested again after six weeks. The donor site heals by re-epithelialisation from the dermis and surrounding skin and requires dressings.
;Full-thickness
:A full-thickness skin graft consists of the epidermis and the entire thickness of the dermis. The donor site is either sutured closed directly or covered by a split-thickness skin graft.
;Composite graft
:A composite graft is a small graft containing skin and underlying cartilage or other tissue. Donor sites include, for example, ear skin and cartilage to reconstruct nasal alar rim defects.
Donor selection
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
Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercellula ...
autograft
Autotransplantation is the transplantation of organs, tissues, or even particular proteins from one part of the body to another in the same person ('' auto-'' meaning "self" in Greek).
The autologous tissue (also called autogenous, autogene ...
(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%. 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
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
Other animal coverings, such as the arthropod exoskeleton, have different de ...
. Recent advances have been successful in applying the cells without damage.
![Skin graft donor site](https://upload.wikimedia.org/wikipedia/commons/b/ba/Skin_graft_donor_site.jpg)
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 Dermatome may refer to:
* Dermatome (anatomy), an area of skin that is supplied by a single pair of dorsal roots
* Dermatome (embryology), the portion of the embryonic paraxial mesoderm, the somite, which gives rise to dermis
* Dermatome (instrument ...
. This usually produces a split-thickness skin graft, which contains the
epidermis
The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and hypodermis. The epidermis layer provides a barrier to infection from environmental pathogens and regulates the amount of water rele ...
with only a portion of the
dermis
The dermis or corium is a layer of skin between the epidermis (with which it makes up the cutis) and subcutaneous tissues, that primarily consists of dense irregular connective tissue and cushions the body from stress and strain. It is divided i ...
. The dermis left behind at the donor site contains
hair follicle
The hair follicle is an organ found in mammalian skin. It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions. The hair follicle regulates hair growth via a complex interaction between h ...
s and
sebaceous gland
A sebaceous gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin of mammals. In humans, sebaceous glands occur in the greatest number ...
s, 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.
The graft is carefully spread on the bare area to be covered. It is held in place by a few small
stitches or
surgical staple
Surgical staples are specialized staples used in surgery in place of sutures to close skin wounds or connect or remove parts of the bowels or lungs. The use of staples over sutures reduces the local inflammatory response, width of the wound, a ...
s. The graft is initially nourished by a process called plasmatic imbibition in which the graft "drinks plasma". New blood vessels begin growing from the recipient area into the transplanted skin within 36 hours in a process called capillary inosculation. To prevent the accumulation of fluid under the graft which can prevent its attachment and revascularization, the graft is frequently
mesh
A mesh is a barrier made of connected strands of metal, fiber, or other flexible or ductile materials. A mesh is similar to a web or a net in that it has many attached or woven strands.
Types
* A plastic mesh may be extruded, oriented, ex ...
ed 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.
An increasingly common aid to both pre-operative wound maintenance and post-operative graft healing is the use of
negative pressure wound therapy
Negative-pressure wound therapy (NPWT), also known as a vacuum assisted closure (VAC), is a therapeutic technique using a suction pump, tubing and a dressing to remove excess exudate and promote healing in acute or chronic wounds and second- ...
(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.
Z-plasty
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 bad 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.
Z-plasty is described as the plastic surgeon's best friend being of paramount importance and a frequently used method in both single multiple forms.
Risks
Risks for the skin graft surgery are:
*
Bleeding
Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...
*
Infection
An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dise ...
* Loss of grafted skin
*
Nerve damage
Nerve injury is an injury to nervous tissue. There is no single classification system that can describe all the many variations of nerve injuries. In 1941, Seddon introduced a classification of nerve injuries based on three main types of nerve f ...
*
Graft-versus-host disease
Graft-versus-host disease (GvHD) is a syndrome, characterized by inflammation in different organs. GvHD is commonly associated with bone marrow transplants and stem cell transplants.
White blood cells of the donor's immune system which remain wit ...
Rejection may occur in
xenografts
Xenotransplantation (''xenos-'' from the Greek meaning "foreign" or strange), or heterologous transplant, is the transplantation of living cells, tissues or organs from one species to another. Such cells, tissues or organs are called xenograft ...
. To prevent this, the person receiving the graft usually must be treated with long-term
immunosuppressant
Immunosuppressive drugs, also known as immunosuppressive agents, immunosuppressants and antirejection medications, are drugs that inhibit or prevent activity of the immune system.
Classification
Immunosuppressive drugs can be classified in ...
drugs.
Prognosis
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.
History
![Device for skin wound closure](https://upload.wikimedia.org/wikipedia/commons/f/f2/Device_for_skin_wound_closure.jpg)
Skin grafting, in more rudimentary forms, has been practiced since ancient times. The
Ebers Papyrus of
ancient Egypt contains a brief treatise on xenografting. Around 500 years later, members of the
Hindu
Hindus (; ) are people who religiously adhere to Hinduism.Jeffery D. Long (2007), A Vision for Hinduism, IB Tauris, , pages 35–37 Historically, the term has also been used as a geographical, cultural, and later religious identifier for ...
Kamma
Kamma may refer to:
*Kamma (caste), a caste or social group found largely in Southern India
*Kamma, India, village in Punjab, India
*The Pali and Ardhamagadhi term for karma
*Bava Kamma, a traditional Jewish civil law procedure (1st volume of Nezi ...
caste are described as performing skin grafts which included the usage of subcutaneous fat. The 2nd century AD Greek philosopher
Celsus
Celsus (; grc-x-hellen, Κέλσος, ''Kélsos''; ) was a 2nd-century Greek philosopher and opponent of early Christianity. His literary work, ''The True Word'' (also ''Account'', ''Doctrine'' or ''Discourse''; Greek: grc-x-hellen, Λόγ ...
is also known to have developed a method to reconstruct the foreskins of
Jewish
Jews ( he, יְהוּדִים, , ) or Jewish people are an ethnoreligious group and nation originating from the Israelites Israelite origins and kingdom: "The first act in the long drama of Jewish history is the age of the Israelites""The ...
men using skin grafts, as
circumcision
Circumcision is a surgical procedure, procedure that removes the foreskin from the human penis. In the most common form of the operation, the foreskin is extended with forceps, then a circumcision device may be placed, after which the foreskin ...
was considered barbaric in Greek and Roman society.
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. Today, skin grafting is commonly used in dermatologic surgery. 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.
Alternatives to skin grafting
There are alternatives to skin grafting including skin substitutes using cells from patients, 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.
Other skin substitutes include Allograft, Biobrane, TransCyte, Integra, AlloDerm, Cultured epithelial autografts (CEA).
There are medical devices that helps 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.
See also
*
Tissue engineering
Tissue engineering is a biomedical engineering discipline that uses a combination of Cell (biology), cells, engineering, Materials science, materials methods, and suitable biochemistry, biochemical and physicochemical factors to restore, maintai ...
References
External links
Skin graft MedlinePlus Medical Encyclopedia. Parts of this US Federal Government public domain text were used in the article.
{{Authority control
Tissue transplants
Plastic surgery