Ghép Da: Chỉ Định, Ứng Dụng Và Các Nghiên Cứu Hiện Tại (2011)

Skin Grafts – Indications, Applications and Current Research
Edited by Marcia Spear


Published by InTech
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Skin Grafts – Indications, Applications and Current Research, Edited by Marcia Spear
p. cm.
ISBN 978-953-307-509-9

free online editions of InTech
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Contents

Preface IX
Part 1
Introduction 1
Chapter 1
Split-Thickness Skin Grafts 3
Tamer Seyhan
Chapter 2
Skin Graft Harvesting and Donor Site Selection 17
Yusuf Kenan Coban, Ahmet Hamdi Aytekin
and Göktekin Tenekeci
Chapter 3
Indications of Skin Graft 35
Abdou Darwish
Chapter 4
Full Thickness Skin Grafts 43
Saikat Ray and Krishna Rao
Part 2
Applications 55
Chapter 5
Lower Third Nasal Skin Grafting 57
James F. Thornton and Emily D. Rapstine
Chapter 6
Penis-Sparing Surgery with Neo-Glans Reconstruction
for Benign, Premalignant or Malignant Penile Lesions 73
Enzo Palminteri, Fernando Fusco,
Elisa Berdondini and Andrea Salonia
Chapter 7
Skin and Soft Tissue Injuries in
Congenital Vascular Malformations 81
Kyung-Bok Lee and Dong-Ik Kim
Chapter 8
Oral Mucosa Graft 97
Ismaila A Mungadi and Ngwobia P Agwu

VI Contents

Chapter 9
Full-Thickness Skin Grafts in Reconstructive
Dermatologic Surgery of Nasal Defects 117
Carmen Fernández-Antón Martínez and Ricardo Suárez-Fernández
Chapter 10
Surgical Treatment of Post-Burn Trophic
Ulcers and Cicatrices of the Foot Calcaneal Area 133
Babur M. Shakirov
Chapter 11
Preputial Skin Grafts 141
Ahmet Bulent Dogrul and Kaya Yorganci
Chapter 12
Treatment of Adult-Acquired Buried Penis 147
W. Britt Zimmerman and Richard A. Santucci
Part 3
Current Research 157
Chapter 13
Skin Graft Preservation 159
Liangpeng Ge, Zhenggen Huang and Hong Wei
Chapter 14
Comparative Study of Skin Graft Tolerance
and Rejection in the Frog Xenopus Laevis 175
Hristina Nedelkovska and Jacques Robert
Chapter 15
The Effect of Human Recombinant Erythropoietin
(rHuEPO) and Tacrolimus (FK506) in Autologous
and Homologous Full Thickness Skin Graft (FTSG)
Take and Viability in a Rat Model 197
Dimitrios Karypidis, Despina Perrea,
Othon Papadopoulos and Alkiviadis Kostakis
Chapter 16
Recent Innovation in Pretreatment for
Skin Grafts Using Regenerative Medicine in the East 221
Hitomi Sano and Shigeru Ichioka
Chapter 17
Application of the Nanocrystalline Silver
in Treatment of Burn Wounds in Children 237
Maya Argirova and Ognian Hadjiiski
Chapter 18
How Does Human Amniotic Membrane Help Major Burn
Patients Who Need Skin Grafting: New Experiences 265
Ali Akbar Mohammadi and Mohammad Kazem Mohammadi
Chapter 19
Influence of Microorganisms on the Healing
of Skin Grafts from Chronic Venous Leg Wounds 277
Tine Yding Wolff, Thomas Bjarnsholt,
Klaus Kirketerp-Møller and Trine Rolighed Thomsen

Contents VII

Chapter 20
Clinical Evaluation of Glyaderm, a Dermal
Substitute Based on Glycerinized Donor Skin 291
Pirayesh A., Richters CD, Hoeksema H,
Verbelen J, Heyneman A and Monstrey S.
Chapter 21
External Wire Frame Fixation for Skin Grafts 299
Rei Ogawa and Hiko Hyakusoku
Chapter 22
Efficacy of Autogenous Dermis
Graft for Wound Coverage 307
Seung-Kyu Han
Chapter 23
Cryopreservation of Skin
Tissues for Skin Grafts 319
Suong-Hyu Hyon
Chapter 24
Sentinel Skin Allograft for Monitoring of
Composite Tissue Transplants Rejection 339
Zamfirescu DG, Lascar I and Lanzetta M
Chapter 25
Immunological Considerations for
Inducing Skin Graft Tolerance 349
Ethel J. Gordon

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Preface

The procedure of skin grafting has been performed since 3000BC and, with modern
technology, has evolved through the years. While the development of new techniques
and devices has significantly improved the functional as well as the aesthetic results
from skin grafting, the fundamentals of skin grafting have remained the same, a
healthy vascular granulating wound bed free of infection. Adherence to the recipient
bed is the most important factor in skin graft survival and research continues introduc-
ing new techniques that promote this process. Biological and synthetic skin substitutes
have also provided better treatment options as well as HLA tissue typing and the use
of growth factors. Even today, skin grafts remain the most common and least invasive
procedure for the closure of soft tissue defects.
It is with great pleasure that I bring you this updated collection of current concepts,
the latest research, and future perspectives on skin grafting. We would like to extend
a sincere thanks to the contributors of this project and encourage them to continue in
their quests for solutions. We would also like to thank the entire staff at InTech for
their ongoing support in the completion of this project and their dedication in bringing
high-quality research and knowledge accessible across the world. It is the intent that
this resource will serve as a reference for clinical decisions and generate ideas for fu-
ture research, that when combined, will continue to optimize both functional and aes-
thetic patient outcomes.

Marcia Spear, DNP, ACNP-BC, CWS, CPSN
Doctor of Nursing Practice
Department of Plastic Surgery
Vanderbilt University Medical Center
USA

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Part 1
Introduction

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1
Split-Thickness Skin Grafts
Tamer Seyhan
Adana Numune Educ. & Train. Hospital
Turkey
1. Introduction
The use of split-thickness skin grafts (STSG) is the most common performed procedures to
close defects unable to be closed with the simple approximation of the wound edges. The
healing of a STSG donor site involves re-epithelialization from the epithelial appendages
that are embedded in the dermis and subcutaneous fat.
STSGs are easy to harvest and are taken directly with a knife or with an instrument such as a
dermatome. STSGs may be expanded in size using a meshing device or surgical knife.
The following topics are discussed in this chapter:

Components of skin

Classification of split thickness skin grafts

Process of graft take and healing

Indications and contraindications of split thickness skin grafts

Preoperative considerations

Split thickness skin graft donor sites and harvesting the graft

Postoperative care of split thickness skin grafts and management of donor site

Complications of split thickness skin grafts

Preservation of split thickness skin grafts.
2. Components of skin
Skin consists of two layers derived from two different embryonic layers. The thinner,
outermost layer is the “epidermis”, which is derived from ectoderm; the thicker, innermost
layer is the “dermis”, which is derived from mesoderm. The epidermis accounts for
approximately 5% of the skin thickness and the dermis comprises the remaining 95%
(Vitness, 1977). The dermis contains connective tissue and skin appendages such as
sebaceous glands, hair follicles and sweat glands. Although sebaceous glands are seated in
the dermis, the hair follicles and sweat glands extend into subcutaneous fat.
The average thickness of human skin varies between 2 and 3 mm. Skin is thickest in the
sacrum, palms, and soles of the feet and is thinnest in the eyelids and in the postauricular
area. The epidermis of the face is relatively constant in thickness and measures
approximately 150 microns; however, dermal thickness varies considerably. The dermis can
be as thin as 200-250 µm in the eyelid and periorbital area, 900-1000 µm in the lip and
forehead regions and as thick as 3 mm on the back skin (Gonzalez-Ulloa et al., 1954).
There are five distinct cellular layers of the epidermis. These layers include (from deep to
superficial) the stratum basale (stratum germinativum), stratum spinosum (prickle cell

Skin Grafts – Indications, Applications and Current Research

4
layer), stratum granulosum, stratum lucidum, and stratum corneum. The Malpighian layer of
the skin is a term that is generally defined as both the stratum basale and stratum spinosum
as a unit. The cells of the epidermis arise from the stratum basale and are called
keratinocytes. Keratinocytes gradually migrate superficially and fill with keratin and lipids
and undergo desquamation throughout life. It has been determined that the renewal time of
the Malpighian layers is about 19 days (Stal et al., 1987). Thus, each epidermal cell spends an
average of 10 days in its migration to the surface. In addition to keratinocytes, melanocytes,
Langerhans, and Merkel cells are also present in the epidermal layer of the skin.
Melanocytes, found in the stratum basale, produce melanin, which is distributed to the
epidermal cells and imparts characteristic pigmentation to the skin. Melanin also shields the
skin from the deleterious effects of ultraviolet radiation by absorbing UV light and trapping
photochemically activated free radicals. The Langerhans cells play a vital role in the
immune response by identifying and processing the antigens for other local
immunocompetent cells. The Merkel cells are found in the stratum basale clustered around
hair follicles and are especially concentrated in the palms and soles. These cells also act as
slowly adapting pressure mechanoreceptors.
The dermis consists of two layers: a thin outer papillary layer and a thick inner reticular layer.
The papillary layer consists of randomly arranged collagen fibers, fine elastic fibers, and
abundant ground substance. The ground substance consists of extracellular fluid and
mucopolysaccharides, primarily hyaluronic acid, chondroitin sulfates, and glycoproteins.
The proportion of ground substance and the production and turnover of collagen decreases
with age and is replaced with fibrous intercellular tissue. The reticular layer is formed by
dense, coarser, branching, collagenous fibers arranged in layers, mostly parallel to the
surface. Fibroblasts make up the majority of cells in the dermis, along with interspersed
mast cells and tissue macrophages. The structural strength of the dermal layer is provided
by collagen. Collagen fibers are synthesized by dermal fibroblasts. The majority of collagen
in the dermis is Type I collagen and constitutes up to 80% of the collagen in skin. Type III
collagen constitutes about 15%, while Type V and Type VI account for the remainder. The
typical ratio of Type I collagen to Type III collagen is 4:1( Kusuma et al., 2010).
The dermo-epidermal junction of human skin appears as an irregularly, wavy line; the
ridges or rete pegs project into the dermis. With aging, these rete pegs diminish and
subsequently lead to a decrease in the surface area of the dermal-epidermal junction.
Branches from cutaneous arteries form a small vessel plexus within the dermis. The
lymphatic plexuses are found in the papillary dermis, directly below the dermal papillary
ridges. The skin possesses a rich supply of sensory nerves, which are organized as deep
dermal and superficial dermal plexus. These nerves convey sensation from the skin to the
brain through specialized receptors for touch (Meissner’s corpuscles), pressure (Pacinian
corpuscles and Merkel cells), temperature and pain (free nerve endings) Additionally, a
network of autonomic fibers provide the primary innervation of cutaneous blood vessels,
pilomotor units in the hair follicles, and the sweat and sebaceous glands (Gaboriau &
Murakami, 2001).
Sweat glands, sebaceous glands and hair follicles are skin appendages. Sweat glands are
found deep in the dermis and even in the subcutaneous tissue. The sweat glands are usually
located deeper than the hair follicles; however, hair follicles reach in the subcutaneous fat of
the bearded area of the male face. There are two types of sweat glands, apocrine and eccrine.
The more numerous eccrine sweat glands are found over the general body surface of

Split-Thickness Skin Grafts

5
humans and open either at the sweat pores on the skin surface or above the opening of the
sebaceous gland in the hair follicle walls. Apocrine sweat glands tend to be concentrated in
the eyelids, axillae, periumblical area and genital area. The apocrine glands become more
active at puberty secrete continuously. The secretions of apocrine glands produce a
characteristic odor; however, the eccrine glands are odorless.
Sebaceous glands are derived from the pilosebaceous unit and are commonly associated
with hair follicles. The sebaceous glands provide lubricant for the hair and skin and are
larger and have more density in the skin of the forehead, nose, and cheeks.
Hair follicles are intradermal epithelial invaginations associated with sebaceous glands and
smooth-muscle bundles called erector pili.
3. Classification of split-thickness skin grafts
Skin grafts are classified according to origin and thickness. Skin grafts are classified as
autograft, allograft (homograft), xenograft (heterograft) and isograft (syngenic) according to the
sources. An autograft is a graft transferred from a donor to recipient site in the same
individual. An allograft (homograft) is a transplant between individuals of the same species.
A xenograft (heterograft) is a graft transplanted between individuals of different species. An
isograft (syngenic) is a graft transplanted between genetically matched genotypes, such as
identical twins.
Split-thickness skin grafts (STSGs) are subdivided into thin, medium and thick STSGs.

Split-thickness skin graft-thin (STSG-T; 0.008-0.012 in. or 0.2-0.3 mm)

Split-thickness skin graft-medium (STSG-M; 0.012-0.018 in. or 0.3-0.45 mm)

Split-thickness skin graft-thick (STSG-THK; 0.018-0.030 in. or 0.45-0.75 mm)
The STSG-T used by early surgeons such Ollier (1872) and Thiersch (1874) have been
replaced by thicker split-thickness grafts (STSG-M, STSG-THK), which include all of the
epidermis and a variable fraction of the dermis (Blair & Brown, 1929). Currently, the most
commonly used split-thickness graft thickness is between 0.012 and 0.018 inch (0.30 to 0.45
mm) in thickness. The average STSG is cut at 0.015 inch and can be checked by inserting a
No.15 blade, which approximates that thickness.



The mesh skin graft was first described by Tanner in 1964 as a method of expanding skin
grafts (Tanner et al., 1964). Preparation of the meshed skin graft is performed with a skin
graft mesher. The graft is placed on a template and is passed through the device. The most
commonly used expansion ratio is 1:1.5, which increases the surface area by 50 percent.
Mesh grafts are primarily useful in two situations: (1) when there is insufficient skin; or (2)
when a very irregular surface must be covered with a graft where a sheet might not adhere
well (Fig. 3c). Also, the drainage of fluid through the slit-like perforations produced by the
meshing procedure prevents hematoma formation and permits the graft to be applied to an
actively bleeding wound. The expanded graft must heal in between the expansion by
epithelization; therefore, the underlying wound may contract significantly.
4. Process of graft take and healing
Grafts initially survive via diffusion, called plasmatic imbibition, and subsequently
inosculation and revascularization occurs. Immediately after a skin graft is placed on the
recipient bed, a fibrin network provides a scaffold for the necessary graft adherence. During

Skin Grafts – Indications, Applications and Current Research

6
the first 48 hours, the graft becomes engorged with plasmatic fluid by means of diffusion. A
poorly vascularized bed requires a longer period of plasmatic imbibition before the graft is
revascularized. The ingrowth of capillary buds from the recipient bed into the open vessels
on the undersurface of the graft is called inosculation and occurs within 2 to 4 days.
Revascularization is thought to be directed by angiogenic factors and can be restored within
5 to 7 days. Thin grafts of skin are revascularized more rapidly than thick grafts. Lymphatic
circulation, which is established by the fifth day, may aid in decompressing the increased
graft interstitial fluid. Within the first week the thickness of the epidermis can increase
seven to eightfold. Dermal fibroblasts proliferate vigorously in healing skin grafts after an
initial decrease of three days. By the seventh to eighth day there is a marked hyperplasia of
fibroblasts as the graft begins to heal.
Almost all skin grafts are capable of sweating in response to stimulation of the nerves that
ingrow from the recipient site. STSGs often have deficient function of sebaceous glands and
therefore should be lubricated for three months. Most patients with skin grafts do not obtain
completely normal sensation. The recovery of sensation in humans can begin as early as one
to two months after surgery, and may be abnormal during the first year. Full-thickness skin
grafts appear to achieve better sensation than split-thickness grafts, although the rate of
return of innervation is faster in STSGs.
5. Indications and contraindications of split-thickness skin grafts
5.1 Indications of split-thickness skin grafts

Immediate coverage of clean soft tissue defects and accelerated wound healing (Fig.
1a,b.)

Immediate coverage of burn defects and reduced fluid loss from the wounds.

Prevention of scar contracture and enhanced cosmesis in superficial wounds.


Fig. 1. (a) View of the traumatic clean soft tissue defect before split-thickness skin grafting.
(b) Post-operative view of the patient after split-thickness skin grafting.
5.2 Contraindications of split-thickness skin grafts

Infected wounds have poorly vascularized and necrotic tissue. After management of the
infection and necrotic tissues, skin grafting becomes suitable (Fig. 2a,b,c; Fig. 3 a,b,c,d).

Split-Thickness Skin Grafts

7


Fig. 2. (a). Preoperative view of infected, poorly vascularized wound with necrotic tissues.
Fig. 2. (b). After management of the infection and necrotic tissues of the wounds.
Fig. 2. (c). Postoperative view of the defects after split-thickness skin grafting.



Fig. 3. (a). Preoperative view of infected, poorly vascularized wound with necrotic tissues.
Fig. 3. (b). After management of the infection and necrotic tissues of the wounds.
Fig. 3. (c,d). Postoperative view of the defects after split-thickness skin grafting.

Skin Grafts – Indications, Applications and Current Research

8

Exposed bone without periosteum, cartilage without perichondrium, tendon without
paratenon or nerve structures (Fig. 4.).



Fig. 4. View of the defect on the cruris, which is not suitable for grafting.
6. Preoperative considerations
Wounds considered for skin grafting must have a well vascularized and non-infected
wound bed. A granulating wound with a healthy appearance usually denotes sufficient
nutritional status and overall health of the patient (Fig. 2b, 3b). Hypertrophic granulation
tissue needs to be either trimmed or flattened in order to enhance graft take and epithelial
migration. Epithelial migration at the edges of the granulating surface may be a sign that the
wound is ready for application of a skin graft. Serial debridements, culture-specific
antibacterial therapy and frequent dressing changes continue to be the mainstay of
preparing good recipient bed.
Pretreatment of a wound with vacuum-assisted closure (V.A.C.® KCI, USA, Inc., San
Antonio, TX, USA) therapy is advisable to increase granulation tissue, tissue perfusion and
decrease edema, bacterial colonization, wound exudate in chronic wounds (Fig.5 a,b,c)
(Teot, 2004). VAC therapy consists of a controlled application of continuous or intermittent
subatmospheric pressure to a sponge-like wound dressing to promote healing (Argenta &
Morykwas, 1997). Classic VAC therapy is not advisable when the wound is infected. An
alternative method for infected wounds is the use of V.A.C. ® Instill™, which has an
additional instillation line for topical antiseptics and antibiotics and removal of topical
solutions from the wound site (Bernstein & Tam, 2005). Silver-impregnated sponges (V.A.C.
GranuFoam Silver®) provide continuous delivery of silver directly to the wound bed and
may be preferred in infected wounds during VAC therapy.

Split-Thickness Skin Grafts

9

Fig. 5. (c) View of a venous ulcer on the left medial malleolus. (b) The use of VAC dressing
for preparing the wound bed for grafting. (a) View of the freshly granulating venous ulcer
defect after four VAC dressing changes.
6.1 Split-thickness skin graft donor sites and harvesting the graft
STSGs can be taken from any area of the body, including the scalp and extremities (Fowler
& Dempsey, 1998). When possible, STSGs should be taken from hidden areas such as the
anterolateral thigh and lateral buttock. If STSGs are required for the face, skin harvested
from “blush zones” such as the supraclavicular area and scalp is preferable. A thin graft
(0.010 inch or less) leaves the hair follicles in the donor scalp and avoids hair growth in the
recipient bed. Also, an important source of STSGs is avulsed skin in trauma or surgically
removed skin.
Skin graft harvesting can be performed by various tools including knives and dermatomes
(Table 1, Fig. 6 a,b,c,d).

Skin graft harvesting tools
1.
Free-hand knives
2.
Various types of dermatomes

Drum (manually operated)

Powered dermatomes (Electric or air);
-
Battery operated Davol dermatome
-
Humeca Battery operated dermatome
-
Padgett dermatome
-
Zimmer air dermatome
Table 1. Skin graft harvesting tools
Free-hand knives are manual dermatomes. The large Humby-type knives and smaller
Goulian type knives are used for harvesting the STSG manually but provide grafts with
irregular edges and grafts of variable thickness (Fig. 6a). Of the powered dermatomes, the
Padgett dermatome is lighter and is easy to handle and comes in three widths: small-3
inches wide, medium-4 inches wide, and giant-5 inches wide (Fig.6c). The thickness is
determined by turning the setting dermatome knob to the appropriate thickness.
The dimensions of the graft are marked 15-20% larger than the dimensions of the defect. The
skin is lubricated with sterile Vaseline ointment to facilitate graft cutting. It is essential to
keep the donor area surface flat, taut and stretched, for smooth, uniform thickness during
graft cutting. An assistant applies counter-tension on the skin during advancing of the
dermatome and graft harvest is performed in a proximal to distal direction. An surgical

Skin Grafts – Indications, Applications and Current Research

10
assistant can pick up the ends of the skin graft with forceps while the surgeon harvests the
graft with the dermatome.


Fig. 6. The most popular tools for skin graft harvesting. (a) Watson’s modification of Humby
knife. (b) Humeca Battery operated dermatome. (c) Padgett Dermatome. (d) Zimmer air
dermatome.
6.2 Postoperative care of split-thickness skin grafts and management of donor site
The graft is placed on the recipient bed, trimmed with scissors and fixed with sutures or
metal staples. Serous fluid or blood beneath the graft can be a barrier to graft take and a
source of infection that will result in graft loss. Multiple small “pie crust” incisions with a
≠11 scalpel blade or fine scissors provide drainage of the fluid or blood beneath the graft. In
most cases of skin grafting, the optimal dressing is a bolus or tie-over dressing to ensure
contact and immobilization between the graft and the host bed. A circumferential
compression dressing and a plaster can be used for immobilization in extremity skin grafts.
A tie-over dressing is fashioned by placing sutures around the periphery of the graft and is
tied over a piece of fine mesh, ointment impregnated gauze, covered with cotton sheeting or
cotton balls. The tied sutures gently press the dressing down onto the skin graft, which in
turn is pressed onto the wound bed. This maneuver immobilizes the graft on the wound and
prevents hematoma collection. Before the tie-over dressing is applied, the surgeon should
ensure that there are no blood clots underneath the graft. The tie-over dressing is left in

Split-Thickness Skin Grafts

11
place for three or four days. After removal of the dressing, small collections of seroma may
be evacuated by cutting over the top of the graft and an ointment impregnated gauze
dressing applied for another 2 or 3 days. When the skin graft is stable and adherent,
antibiotic ointment or another mild lubricating agent is used for three months.
Negative pressure dressing (VAC® therapy) can be used to facilitate skin graft adherence
when grafting difficult wounds (e.g. radiated wounds, wounds with irregular or mobile
recipient beds and in difficult anatomic locations (Schneider et al., 1998; Scherer et al., 2002)
(Fig. 7a,b,c,d.). The VAC dressing is applied to the STSG at 125 mmHg “continuous” mode
suction after the STSG is covered with a single layer of non-adherent Chlorhexidine or
Xeroform gauze.


Fig. 7. (a) View of sternal wounds with irregular and mobile recipient bed. (b) Application of
VAC dressing on STSG covered with a single layer of non-adherent Chlorhexidine gauze. (c)
View of grafted defect after removal of VAC dressing on the fourth postoperative day. (d)
Late postoperative view of the same patient.
6.3 Donor site healing and maintenance
The healing of the donor site occurs by epithelial migration from the epithelial remnants in
the dermis such as hair follicles, sebaceous gland, and sweat glands. Epithelial migration
also occurs at the wound margins. After harvesting a STSG, the donor site is treated with
topical, epinephrine-soaked sponges to reduce bleeding and then a single layer of non-

Skin Grafts – Indications, Applications and Current Research

12
adherent Chlorhexidine or Xeroform gauze is applied to the donor site, followed by a layer
of bulky gauze on top of this. The next day, the outer gauze is removed, leaving behind the
Chlorhexidine or Xeroform gauze, which can be allowed to air dry; a gentle heat lamp
application speeds epithelization. In an area where external contamination is likely, a closed
dressing is preferable. The more superficial a STSG is cut, the faster the donor site will heal.
The healing of the STSGs donor sites take place over seven to fourteen days (Fig. 8 a,b).
Donor sites from which thicker split grafts are cut may not heal for several weeks
Alternatively, donor site are dressed with artificial semi-permeable transparent dressings
(e.g. Biobrane®, Opsite® or Tegaderm®) or biologic dressings (e.g. cadaveric skin, sterile
irradiated allograft, pig skin, amniotic membrane, cultured keratinocyte grafts) (Fedman,
1991; Voineskos, 2009). Thin STSGs usually leave minimal scarring, whereas the thicker
STSGs tend to produce hypertrophic scarring in some patients.









Fig. 8. (a) View of a STSG donor site on the right anterolateral thigh. (b) View of the same
donor site on the fourteenth day.
6.4 Complications of split-thickness skin grafts
Graft contraction, graft failure, hyperpigmentation, itchiness and dryness of the graft,
durability and growth problems are the most common complications of split- thickness skin
grafting.
Primary contraction, an elastic recoil of the skin caused by retractile forces, occurs as soon as
the graft is harvested. The contraction of a healing graft and wound is referred to as
secondary contraction. Secondary contraction, a longer process and clinically more important,
is probably caused by a combination of skin graft and host bed contraction. The dermal
component of grafted skin appears to exert the main influence on secondary contraction.
The thinner the skin graft, the less the primary graft contracture and the more marked the

Split-Thickness Skin Grafts

13
secondary graft contracture. Primary graft contracture is approximately 40% of graft surface
for a FTSG, 20% for a medium thickness STSG, and 10% for a thin STSG (Senchenkov et al.,
2009). The contraction of a wound covered by a STSG can be inhibited by splinting, which
needs to be continued for four to six months to overcome the acute effect of the
myofibroblasts.
The causes of split thickness skin graft failure are listed in Table 2. Most skin graft failures
can be ascribed to flaws in the recipient bed. Tissue with limited blood supply, such as bone,
cartilage or tendon or sites with necrosis or infection do not accept skin graft (Fig. 2a, Fig. 3a,
Fig. 4). Chronic wounds must be free of pus and should have a healthy, pink to beefy-red
appearance with an ideal wound pH of 7.4 or higher. All granulation tissues contain
bacteria, but not all are infected. Particular attention should be paid to eliminating
Streptococcus. Wherever possible, underlying systemic health problems causing the wound,
such as venous stasis and arterial occlusion, should be corrected before skin grafting is
attempted.

Causes of Split-Thickness Skin Graft Failure

Inadequate recipient bed (poor vascularity)

Hematoma, seroma

Inadequate graft fixation and graft shearing

Infection (in particular Streptococcus, which can “eat up” a graft within 24
hours)

Technical errors (too thick or too thin graft, upside-down graft.

Systemic health problems and bad nutritional status

Table 2. Causes of Split-Thickness Skin Graft Failure
Hyperpigmentation of the skin graft is variable and depends on the amount of pigmentation
present in the donor site. Generally, STSGs darken more than FTSGs. Although FTSGs
maintain the best pigment match, STSGs often develop significantly dark pigmentation.
Sunshine should be avoided for the first six months by use of sun-blocking agents or
clothing to prevent long-lasting hyperpigmentation developing in a new skin graft. Both
STSGs and their donor sites may scale and remain itchy and dry for many months because
the lubricating sebaceous glands have been temporarily devitalized. Lubrication with greasy
ointment such as Vaseline, lanolin or cocoa butter helps to replace the lubricating function.
Thick STSGs have greater resistance to trauma. Although FTSGs grow successfully in
children, the growth of STSGs may be limited.
7. Preservation of split-thickness skin grafts
In order to close skin defects, skin grafts are best stored on its donor site and harvested
painless within five days (Shepard, 1972). Skin grafts may also be stored for longer periods,
away from the patient, by being refrigerated. Such grafts may be moistened in sterile saline
and then placed in a refrigerator at 4 ºC in a sterile Petri dish labeled with the patient’s name
and the date of graft harvesting. It may be wise to discard grafts after 8 days, although grafts
may be kept for 2 or 3 weeks (Senchenkov et al., 2009).

Skin Grafts – Indications, Applications and Current Research

14
Long-term storage of autografts and allograft requires special techniques to protect against
cell death. Freezing causes tissue death because of concentration within the cell, leaving
behind a lethal concentration of salts. Protective agents such as 15% glycerol or 10%
dimethyl sulfoxide (DMSO) in Ringer’s solution and storage at -70 ºC with liquid nitrogen
help to protect against this type of injury and allow viable skin to be preserved for up to 28
days (Lawrence, 1972). Control of the rate of freezing reduces the damage caused by
intracellular ice crystals. The best results were obtained when grafts were slowly frozen and
rapidly thawed.
The other technique of storage is freeze-drying of skin for storage at room temperature.
Freeze drying maintains most of the structural details of cells and presumably leaves many
of the proteins and enzymes of the tissue intact. The process involves rapid freezing of the
tissue by immersing it in liquid nitrogen or chilled isopentane. High-speed freezing reduces
the mechanical distortion of the microscopic structure caused by the slow growth of ice
crystals in and between the cells. This tissue is subsequently kept frozen while water is
removed from the solid state by sublimation. The dried tissue is usually sealed in a vacuum
and stored at room temperature (Yukna et al., 1977)
Specialized skin banks have been developed to store large amounts of cadaver skin for
treatment of massive burns (Konstantinow, 1991). Standardized techniques for cadaver skin
graft preservation use glycerol and rapid freezing with liquid nitrogen (Ninneman et al.,
1978). The treated allografts are thawed and used for temporary burn dressings, to be
changed every five days. Pigskin xenografts have also been used fresh or frozen for burn
treatment.
8. Conclusion
STSGs constitute the most commonly performed procedures for the closure of skin defects
that can not be closed with the simple approximation of the wound edges. When a patient
has a full-thickness loss-of-skin defect exceeding 30% of the body area, STSGs taken from
the patient are not available in sufficient quantity. Cultured autologous keratinocytes
may be used to close larger open wounds in such situations. Unfortunately, the lack of
dermis makes the epidermal graft rather thin and fragile. Intensive efforts to develop
epidermal and dermal skin substitutes show the greatest potential, at present, for future
success.
9. References
Argenta, L.C., & Morykwas, M.J. (1997). Vacuum-assisted closure: a new method for wound
control and treatment: clinical experience. Ann Plast Surg, Vol. 38, No.6, pp.563-576,
ISSN: 0148-7043
Bernstein, B.H., & Tam, H. (2005). Combination of subatmospheric pressure dressing and
gravity feed antibiotic instillation in the treatment of post-surgical diabetic foot
wound: a case rseries. Wounds, Vol.17, No.2, pp.37-48.
Blair, V.P., & Brown, J.B. (1929). The use and uses of large split skin grafts of intermediate
thickness. Surg Gynecol Obstet, Vol.49, pp.82-97.

Split-Thickness Skin Grafts

15
Fedman, D.L. (1991). Which dressing for split-thickness skin graft donor sites? Ann Plast
Surg, Vol.27, No.3, pp.288-91, ISSN: 0148-7043
Fowler, A., & Dempsey, A. (1998). Split-thickness skin graft donor sites. J Wound Care ,
Vol.7, No.8, pp.399-402.
Gaboriau, H.P. & Murakami, C.S. (2001). Skin anatomy and flap physiology. Otolaryngol Clin
North Am, Vol.34, No.3, pp.555-69, ISSN: 0030-6665
Gonzalez-Ulloa, M.; Castillo, A., Stevens, E., Alvarez, Fuertes, G., Leonelli, F. & Ubaldo F.
(1954). Preliminary study of the total restoration of the facial skin. Plast Reconstr
Surg, Vol.13, No.3, pp.151-161, ISSN: 0032-1052
Konstantinow, A., Mühlbauer, W., Hartinger, A., & von Donnersmarck, G.G. (1991). Skin
banking: a simple method for cryopreservation of split-thickness skin and cultured
human epidermal keratynocytes. Ann Plast Surg, Vol.26, No.1, pp. 89-97, ISSN:
0148-7043
Kusuma, S., Vuthori, R.K., Piliang, M., & Zins, J.E. (2010). Skin Anatomy and Physiology. In:
Plastic and Reconstructive Surgery, Siemionow, M.Z., Eisenmann-Klein, M. (Eds)
pp.161-171., Springer-Verlag, ISBN 978-1-84882-512-3, USA.
Lawrence, J.C. (1972). Storage and skin metabolism. Br J Plast Surg, Vol.25, No.4, pp.440-453,
ISSN: 0007-1226
Ninneman, J.L., Fisher, J.C., & Frank, H.A. (1978). Clinical skin banking: a simplified system
for processing, storage, and retrieval of human allografts. J Trauma, Vol.18, No.10,
pp. 723-725, ISSN: 0022-5282
Scherer, L.A., Shiver, S., & Chang M. (2002). The vacuum assisted closure device: a method
of securing skin grafts and improving graft survival. Arch Surg, Vol.137, No.8,
pp.930-933, ISSN: 0004-0010
Schneider, A.M., Morykwas, M.J., & Argenta, L.C. (1998). A new and reliable method of
securing skin grafts to the difficult recipient bed. Plast Reconstr Surg, Vol.102, No.4,
pp.1195-1198, ISSN: 0032-1052
Senchenkov, A., Valerio, I.L., & Manders, E.K. (2009). Grafts. In: Plastic Surgery: Indications
and Practice, Guyuron, B., Eriksson, E., Persing, J.A. (Eds.)pp. 95-104, Elsevier, ISBN
13: 978-1-4160-4081-1, USA .
Shepard, G.H. (1972). The storage of split-skin grafts on their donor sites. Clinical and
experimental study. Plast Reconstr Surg, Vol.49, No.2, pp.115-122, ISSN: 0032-
1052
Stal, S., Spira, M., & Hamilton, S. (1987). Skin morphology and function. Clin Plast Surg,
Vol.14, No.2, pp.201-208, ISSN: 0094-1298.
Tanner, J.C., Vandeput, J., & Olley, J.F. (1964). The mesh skin graft. Plast Reconstr Surg,
Vol.34, (Sep 1964), pp.287, ISSN: 0032-1052
Teot, L., (2004). The theory of negative pressure wound therapy (NPWT). Wounds, Vol.16,
No.2, (Suppl), pp. 2-5,
Vitness, LM. (1977) Grafting of Skin. Surg Clin North Am, Vol.57, No.5, pp. 939-960, ISSN:
0039-6109
Voineskos, S.H., Ayeni, O.A., McKnight, L., Thoma, A. (2009). Systematic review of skin
graft donor-site dressings. Plast Reconstr Surg, Vol.124, No.1, pp.298-306, ISSN:
0032-1052

Skin Grafts – Indications, Applications and Current Research

16
Yukna, R.A., Tow, H.D., Carrol, P.B., Vernino, A.R., & Bright, R.W. (1977). Evaluation of the
use of freze-dried skin allografts in the treatment of human mucogingival
problems. J Periodontol, Vol.48, No.4, pp.187-193, ISSN: 0022-3492

2
Skin Graft Harvesting and Donor
Site Selection
Yusuf Kenan Coban, Ahmet Hamdi Aytekin
and Göktekin Tenekeci
Inonu University, Medical Faculty, Plastic Reconstructive
and Aesthetic Surgery Department, & Burn Unit, Malatya
Turkey
1. Introduction
Acute and chronic wounds are characterized by breakdown of the integrity of the soft tissue
envelope surrounding any portion of the body. Flaps and grafts are the two main surgical
procedures utilized to repair soft tissue loss. A simple skin graft applied as a thin layer
harvested with a dermatome, a scalpel or a special knife may provide a durable coverage. A
free skin graft is a piece of skin that has been completely separated from its local blood
supply and transferred to a wound at another site, where it must establish new vascular
connections through the recipient bed to survive. Skin grafts usually are the first
consideration when primary wound closure cannot be achieved. This is true especially for
deep burns of wide body areas.(Rudolph R, Ballantyne DL. Skin grafts. In: McCarthy JG, ed.
Plastic Surgery. Philadelphia: Saunders; 1990:221–274) A skin graft would be contraindicated,
if inosculation from the recipient bed is unreliable with repeated motion or trauma to the
area, or in wound infection (Paletta CE, Pokorny JJ, Rumbolo P. Skin grafts. In: Mc- Carthy
JG, ed. Plastic Surgery. Philadelphia: Saunders Elsevier; 2006:293–316.)
2. Historical perspective regarding to skin grafting
Sir Astley Cooper removed skin from an amputed thumb and used it for stump defect
covarage in 1817 (Tiersch C : Über Hautverplanzung. Verh Dtsch Ges Chir 15-17, 1886).
Nevertheless skin grafting was not fully accepted for clinical use untill the last quarter of the
19th century. Reverdin was first to draw attention to the technique by successfully
performing small pinch grafts in 1972 (Reverdin JL: De la greffe epidermique. Arch Gen
Med 19:276;555, 703, 1972.) In 1874, Thiersch extended the use of the pinch graft using large
sheets of thin skin grafts to cover the wounds (Tiersch C : Über Hautverplanzung. Verh
Dtsch Ges Chir 15-17, 1886.) Blair and Brown (1929) first used the term “intermediate split-
thicknes graft” (Blair VP, Brown JB: Use and uses of large split skin grafts of intermediate
thickness. Surg Gynecol Obstet 49: 82-97, 1929.) Afterwards, Padgett described a technique
for thick skin grafting (Padgett EC. Skin grafting of the burned patient. Plast Reconstr Surg.
2(4): 368-74, 1946). Skin grafting has been the most commonly used technique for
reconstruction of cutaneous defects over the last decades.

Skin Grafts – Indications, Applications and Current Research

18
3. Techniques of harvest in different types of skin grafts
Skin grafts may be physically in one of these three forms; meshed, sheet (unmeshed),
pinch/punch. Each type of skin graft has its own harvesting technique. A preoperative plan
and surgical judgement is necessary for determining which type of graft will be used. Full
thickness skin grafts include all skin appendages, the epidermis and full-thickness of
dermis, and splitt-thickness skin graft include a superficial portion of dermis together with
epidermis and some of the skin appendages. Many techniques of skin grafting require little
experience and only basic surgical equipment. A classification of skin grafts according to
depth is seen in Table 1.

Name
Thickness (mm)
Split thickness
Thin (Thiersch-Ollier)
0.15-0.3

Intermediate (Blair-Brown)
0.3-0.45

Thick (Padgett)
0.45-0.6
Full thickness
(Wolfe-Krause)
>0.6
Table 1. Classification of skin grafts according to depth
3.1 General principles for skin grafting
Grafting should be done only onto a well-vascularised viable wound surface, such as
granulating tissue. Whether the impairments to wound healing and closure are local or
systemic, they must be addressed appropriately. Proper wound preparation certainly
determines the success of skin grafting. Apropriate debridement is necessary for wound bed
preparation. Debridement by hydrosurgical, biological and chemical methods has been
reported (Meaume S.Methods of non surgical debridement of wounds in 2011.:Soins 752:44-
47; 2011). Simple metallic sponges of the sort used in the kitchens which can be sterilized
easily are effective for intraoperative surgical debridement. Simple wiping of the wound
surface may be adequate enough to remove debris, especilally granulation tissue and soft
eschar. Optimizing the patient’s medical condition before surgical closure of a wound can
mean the difference between a succesfull outcome and an undesirable one. A delay in
grafting a suboptimal wound is also good surgical judgment.
3.2 Splitt thickness skin graft
Split-thickness skin grafts (STSG) can be harvested rapidly by using a mechanical
dermatome. The donor site will heal because the whole of this epidermis can regenerate
from deeper parts of the dermis which has left behind on ground. During the harvets by
using a harvesting apparatus (dermatome), the donor site should be stabilized and fixed in
order to opimise the procedure. The technique of skin grafting is often learned and practiced
today using electric or air-powered dermatomes the manuplation of which doesn’t require
any skill when compared to the harvest by free hand knives.
3.2.1 Types of dermatomes
A dermatome is a surgical instrument used to produce thin slices of skin from a donor site
and is the main tool for skin graft harvesting. Dermatomes can be operated either manually
or electrically. The use of different types of safety razors as a dermatome has been described
by some authors. Goullian (1968) constructed a skin grafts set from a weck straight razor by

Skin Graft Harvesting and Donor Site Selection

19
adding a fixed handle and a choice of interchangeable space setters to cut different thickness
of grafts.(Goullian D.A new economical dermatome Plast Reconst Surg 42: 85, 1968) Snow
described the use of a shick injector razor (Snow JW. Safety razor dermatome Plast Reconstr
Surg 41: 184, 1968). Shoul (1966) modified a gillette safety razor by filling out the central
strut of the safety guard using another blade as a skim. (Shoul M.Skin grafting under local
anesthesia using a new safety razor Am J Surg 112.959, 1966) These old- fashioned
instruments and shaving blades are difficult to obtain today.
Manual dermatomes are also known as hand-held dermatomes. Occasional users are more
likely to use the hand-held knife where adjustment of depth is more difficult. Though most
modern graft knives, e.g. the Humby knife and the modified Watson knife, possess an
adjustment facility, the appropriate setting is usually determined by eye-balling. Humby
skin grafting knife is the most popular. Disadvantages of hand-held knives are harvesting of
grafts with irregular edges and grafts of variable thickness. Additonally, its lenght makes
many areas inaccessable to harvest skin grafts which poses another disadvantage (Figure 1).
This is especially true in infants where the convexity of limbs allows grafts after only an inch
wide. In fact with the narrow dermatome (modified safety razor, sober hand dermatome)
one can take skin graft practically from anywhere on the body. Use of single blade for
coverage of mild to moderate defects is sufficient while the very large defects may require
more. The simplicity of the narrow dermatome machine is such that skin grafting can be
done by every surgeon. The dermatome is hold firmly against the tightly hold skin at a
predetermined angle and the graft of the desired lenght is harvested quickly. Lubrication
and a tonque depressor facilitate even harvesting of STSG. Use of a semipermeable
membrane in STSG donor site before harvesting has been described for minimising trauma
to the graft. (Sams HH, McDonalds MA, Stasko T.Usefull adjunct to harvest split-thickness
skin grafts. Dermatol Surg:30(12pt 2): 1591-1592, 2004).



Fig. 1. An example of hand dermatome (schink type): frontal view (top) and lateral view
showing Skin Graft thickness adjustment mechanism (bottom).

Skin Grafts – Indications, Applications and Current Research

20
Electrical dermatomes are better for cutting out thinner and larger strips of skin with a more
homogenous thickness. Dermatomes which were operated by air pressure, such as Brown or
Zimmer dermatome, achieved higher speed and precision. Since an electrical dermatomes
require electrical energy supply through an electrical cable. It is impractical to sterilize those
cable during the operation. Humeca developed a new dermatome for free handed
harvesting skin graft with a predetermined thickness of about 0,25 mm. (FIGURE 2).



Fig. 2. Humeca electrical dermatome, whole body of cordless electrical dermatome (top
right), justification site (top left), easily harvesting STSG (bottom left), and rechargeable
batteries with its charging unit (bottom right).
3.2.2 Graft expansion
Expansion techniques are used to speed up the epithelialization process while diminishing
the need for total amount of graft to be harvested. Various ways to expand grafts have been
described including pinch grafts, meshing and micrografting (Meek technique) are among
these ways. An expanded graft presents a larger cumulative perimeter through which
epithelial outgrowth can proceed.
3.2.3 Meshing
Meshing is the term used for slitting a sheet graft and stretching it to open up prior to
transplantation. This method of grafting has wide application in the treatment of burns and
large contaminated wounds. Meshing ratios greater than 1 : 3 can be difficult to handle, as
the skin curls on itself. When larger expansion ratios are desired, it is recommended to use
meek micrograft technique for faster healing in body regions like thorax and abdomen. A

Skin Graft Harvesting and Donor Site Selection

21
well-known type of mesher contains circular blades and requires the use of grooved plastic
carriers (Figure 3). By using such an instrument the blades are forced under pressure to roll
over the grooved carrier, thus cutting the graft at locations where the blades contact the
carrier. Conventional skin graft carriers have a groove pattern of straight lines from the left
to the right under a certain angle. Humeca introduced V-shaped groove pattern which
prevents distortion during cutting a mesher. Advantage of these V carriers is to achieve
quickly a more regular meshed grafts.
Humeca supplies two diferent expansion ratios (1:1,5 and 1 : 3) and one perforation carrier
(1:1 ratio). (Humeca Mesher and V- carries.Properties and instructions for use;
) Mesh grafts are expanded by a mechanical device and
are used to cute multiple slits in the graft to be stretched. Grafts can be meshed at ratios of
1:1,5 – 1: 4 (FIGURE 4).




Fig. 3. Two different types of the humeca v-carries (6.V10 -1.5 and 6.V10-3.0, thickness 1.0
mm and expansion ratio 1.5 and 3 ).
Meshing allows the leakage of serum and blood from wound, minimizing the risk formation
of hematomes or seromas that could compromise graft survival. Meshed grafts can also be
useful to cover larger surface areas by means of stretching and expanding.

Skin Grafts – Indications, Applications and Current Research

22








Fig. 4. Meshed skin graft at ratio of 1:3 is seen.
3.2.4 Meek technique
Meek (1958) described a technique for expanding a small piece of skin graft with a
dermatome in 1958 ( Meek CP, Successful microdermagrafting using the Meek-Wall
microdermatome – Am. Surg. vol. 29, pp. 61 , 1958). This technique was later modified by
other authors ( Taner C, Vabdeput JF and Olley JF. The mesh skin graft, Plast Reconstr Surg
34 ; 287–292, 1964 and Kreis RW, Mackie DP, Hermans RP and Vloemans AR. Expansion
technique for skin grafts: comparison between mesh and Meek island (sandwiched-) grafts,
Burns 20:; 39–42, 1994) The Meek technique of skin expansion is efficient and effective in
covering an open wound, particularly when there is a paucity of skin graft donor sites.
Meshing of the graft was achieved by passing the carrier that housed the cork so that it was
secured in a grille, when passed through the cutting machine. This device (Meek–Wall
dermatome) was equipped with 13 circular blades that cut the graft into 14 strips of skin
each 3 mm in width. In order to fabricate 196 pieces of micro-sized skin graft, each
measuring 3 mm × 3 mm, the carrier block containing the 14 strips of skin was rotated by
90° and then passed through the cutting machine again (FIGURE 5). The the cut graft by
using Meek technique was already placed on to a base which is elastic and has a speciality
of preventing recoiling.

Skin Graft Harvesting and Donor Site Selection

23


Fig. 5. Vertically and horizontally parelel cuts with following traction in two different
directions expands the graft into multiple square mini skin grafts.
The cut grafts were transferred to another carrier, made of polyamide gauze with aluminum
foil backing, by removing the cork plate, the epidermal surface of the graft being sprayed
with adhesive. Peeters and Hubens showed that the MEEK technique the required graft
donor site area is about half of that required with meshing. (Peeters R, Hubens A, The mesh
skin graft – true expansion rate – Burns, vol. 14 (3); 239-24 , 1988). In patients with more than
%50 of fullthickness body skin surface loss , the use of modified meek skin grafting
technique application for body areas except face, neck and hand regions with an expansion
ratio of 1:4 and 1:6 has been succesfully reported.( Raff T, Hartmann B, Wagner H, Germann
G. Experience with the modified Meek technique. Acta Chir Plast. 38 (4): 142 – 146, 1996)
3.2.5 Sheet grafts
Sheet grafts where the superficial part of skin taken from another part and sliced are STSGs
and harvested by a special instrument which is called as dermatome, whereas FTSGs are
obtained with scalpel. Sheet grafts are applied without altering following harvest. STSG
sheet grafts are usually applied to neck and face areas in where meshed grafts should not be
used due to aesthetic concerns. (FIGURE 6). Sheet grafts are STSGs and they can be in there
forms; thin, intermediate and thick..
3.3 Full thickness skin grafting
Full thickness grafts transfer all skin appendages and nerve endings except those sweat
glands located in the subcutaneous tissue and some of Vater-Pacini corpuscles of palmar
and plantar skin. ( Lever WF: Histology of skin. pp 9-45. In Lever WF, Shaumburg-Lever G
(eds) : Histhopathology of the skin 5th ed.JB Lippincott, Philadelphia 1975. ) FTSG are
especially useful for the repair of defects of the nasal tip dorsum ala lateral nasal sidewall,
hands, eyelids and ear. Wound contraction is minimal and adnexal structures mostly are
harvested together with the graft. An FTSG donor site should be planned in an elliptical
shape to simplify direct closure. After an apropriate size has been determined, an ovoid of
skin is excised from predetermined area with the axis in the direction of minimal tension.
The wound is closed in a standart fashion, undermining the edges as necessary to achieve
approximation. It is sometimes difficult to determine how much skin will be required.
Templates can be prepared using the paper in which the glove is wrapped. FTSGs transfer
all of the skin appendages and nerve endings except those sweat glands located in the

Skin Grafts – Indications, Applications and Current Research

24
subcutaneous tissue and some of the Vater-Pacini corpuscles of palmar and plantar skin.
There are two techniques for harvesting FTSGs. In the meticulous technique where a sharp
dissection is done, only the skin may be obtained. Second one can be described as rough
technique. After the incision the predetermined graft donor site, graft can be harvested
easily and rapidly by inclusion of subcutaneous fat tissue (Figure 7 and 8).




Fig. 6. Note that sheet grafts are applied to neck and face, whereas meshed grafts are other
body regions where aesthetics are not primary concerns (Top). Note that some remaining
elastic properties of thick STSG is clearly observed (bottom)
In the rapid technique where the skin is harvested with its subcutaneous attachments, there
will be need of a following defatting process, since those structure may prevent graft
vascularisation. Easily harvested with a scalpel, defatting or thinning the dermis increases
the chance of “graft take.”FTSGs are commonly harvested from the inguinal region, flank or
from the postauricular area. These donor sites can be closed primarily, care should be taken
to select a harvest site that does not contain hair.

Skin Graft Harvesting and Donor Site Selection

25

Fig. 7. Rough technique harvesting FTSG: defatting of graft (left), after the procedure (top
right) and prior to the procedure the graft including subcutaneous fat (bottom, right).


Fig. 8. Meticulouse technique for harvesting FTSG.
The most important factors affecting graft take are an inadequate recipient debridement,
hematoma formation and local infection. In order to optimise these factors, Landau et. Al.

Skin Grafts – Indications, Applications and Current Research

26
described the use of negative pressure dressing to prepare graft bed. They found FTSG take
was in excess of 90%, even though a large surface area and a contour surface needed
resurfacing (Landau A, Hudson DA, Adams K, Geldenhuys S, Pienaar C.Full-thickness skin
grafts: Maximising graft take using negative pressure dressings to prepare the graft bed.
Ann Plast Surg 60(6); 661-666; 2008)
3.4 Mini and micro skin grafting
The instruments required are 1.5 or 1.2mm punches, small jeweler's or graft holding forceps,
and a small curved tip scissors for mini skin grafting. For micro skin grafting additional
tools are spraying device, silver’s skin grafting knife and spoon for spreading MSG. Dropper
shallow stainless tray, diamond fraises and wire bushes are other useful tools. Although the
micrograft technique is labour-intensive, if the expansion needed is at least 1:6, the aesthetic
and functional results obtained are comparable to, or better than, those with meshed grafts.
Pinch grafts should be full thickness 2-5 mm in diameter with free spaces of 5-10 mm
between each of the grafts. Punch grafts are obtained by using a punch biopsy instrument,
3-5 mm in diameter (Figure 9). Pinch and punch grafts can also be called as patch or stamp
grafts. Mini punch graft (MPG) may be used in transplantation forrepigmentation surgery of
vitiligo, or some minor skin defects (Lahiri K.Evolution and evaluation of autologous mini
punch grafting in vitiligo..Indian J Dermatol:54(2); 159-167; 2009).


Fig. 9. Mini skin graft harvesting with simple forceps and curved tip scissors(top, , and the
donor site after MSG harvesting (right).MSG that applied to a skin defect are shown
(bottom).
Hair follicular graft (HFG) is like MPG but it contains a single or more hair follicles and thin
sleeve of epidermis and full dermis. HFG can also be called as follicular unit grafts (FU). FU

Skin Graft Harvesting and Donor Site Selection

27
is obtained by two methods; first is by using a special extractor and the second one is the
method which elliptical harvesting of the donor strip providing more hair with less hair
transection per procedure that remains the standard procedure. Although larger punch
grafts and scalp flaps may play role in certain cases. FU transplantation is the culmination of
decades of refinements and evolution of hair transplantation techniques. Hair naturally
groups in groups of one to four individual follicles seperated by intervening soft tissue.
These clumps or groups of hairs are termed follicular units.
The usual donor region is between occipital protuberance and 1 cm above the top of the ear
(FIGURE 10). This donor site can easily be closed primarly.




Fig. 10. Posterior occipital donor site : after the harvest (top) and closing the donor site
primarly (bottom)
The average density in the posterior scalp is 65- 85 FU per cm2. This is the safest place to
harvest hair. The donor ellipse is handed by a surgical assistant and meticulous seperation
of follicular goupings is begun using stereomicroscopic disssection. It is preferred greater
lenght than width in a donor ellipse to achieve the desired number of follicular grouping.
FUextract is the harvesting of individual FU units wtih 1 mm puches (FIGURE 11).
3.5 Composite skin grafting
Donor site selection of composite graft which is composed of multiple structures like skin
and cartilage requires a more complicated approach, as defects of aesthetic subunits has its
own characteristics and needs a more close attention in the repair process. Good examples of
using composite graft are eyelash reconstruction with strip composite eyebrow grafts and
alar rim defect repair with composite auricular graft. Strip composite eyebrow graft is the

Skin Grafts – Indications, Applications and Current Research

28


Fig. 11. A strip obtained from occipital donor site (top) and sliced FUs (bottom)
At first, the strip is divided into slices, much like slicing a loaf of bread, then each sliver is
divided into individual FUs of 1, 2, 3, 4 –hair grafts (FIGURE 12). Upper limits of
transplanted hair follicular unit number changes between 1500- 4500 for each session.


Fig. 12. This HFG is to be scliced into smaller FU grafts.

Skin Graft Harvesting and Donor Site Selection

29
most suitable as its properties are very similiar to those of the original eyelash hairs. (Kasai
K.Eyelash resonstruction with strip composite eyebrow graft. Head and Neck Surg
60(6);649-651; 2008) (Coban YK, Geyik Y.An ideal composite graft donor site for postburn
alar rim deficiencies: root of helix . J Craniofac Surg: 21(4);1246; 2010)

Types of composite skin
grafts
Used for
Additional content
tissue
Strip eyebrow graft
Eyelash reconstruction
Subcutaneous fat
Conchal / helical composite
grafts
Alar rim / columella
restoration
Auricular cartilage
Scalp punch, pinch
(follicular) grafts
Hair restoration
Subcutaneous fat
Strip scalp grafts
Eyebrow reconstruction
Subcutaneous fat
Table 2. Types of skin composite grafts.
4. Donor site selection criteria
The selection of donor site is essential to achieve the best possible outcome. Donor sites,
from which the skin grafts are taken, can be virtually anywhere in the body. Main criteria
related with donor site selection is about which kind of skin graft is to be used. The
importance of clothing styles particularly those swimwear must be considered in selection
of donor site. The closer the donor site is to defect, the better the color and texture match.
FTSG in general, convex areas of the body are easier to harvest than concave areas. With a
very thin STSG the scar at the donor site will be the least pronounced. The anterior thigh
provides a large expanse of skin for larger skin grafts. Split-thickness skin graft donor sites
are more numerous than those for full-thickness skin grafts, because the former heal
spontaneously, mainly by reepithelialization from epidermal appendages found in the
residual dermis. Whereas harvesting FTSG from any part of body leaves a donor site scar
behind. So when using FTSG hidden donor areas by clothing are usually selected. A graft
taken from skin adjacent to the surgical defect, known as Burrow’s graft often provides an
ideal match with respect to both color and texture. For example, skin taken from nasolabial
fold may be used to close small nasal tip defects and may often supply a degree of
sebaceous quality. Similarly clavicular skin may be used for a defect of photodamaged area,
as this site provides a better color match. The ulnar border of the hypothenar area is an
excellent source of small grafts for the fingertips. Preputium may be used as FTSG donor
site when circumcision is also planned.(Yıldırım S, Akan M, Akoz T, Tanoglu B.Preputium:
an overlooked skin graft donor site. Ann Plast Surg:46(6);&30-634; 2001).
4.1 Choice of graft
Best choice for a skin graft depends on the location of the defect. The actual principle to be
cared is the similarity between the donor and recipient site characteristics. The properties
that are expected from the grafted skin are the expected aesthetic appearence, the size of
defect, donor availability, donor site morbidity. Palmar skin of the instep is the best
replacement of the palmar skin of the digit and hand. In other way, plantar defects are
usually repaired glabrous skin grafts taken from hypothenar hand regions. (Wu LC,
Goutlieb LJ. Glabrous Dermal Grafting: A 12-Year Experience with the Functional and
Aesthetic Restoration of Palmar and Plantar Skin Defects Plast.Reconstr. Surg. 116: 1679,

Skin Grafts – Indications, Applications and Current Research

30
2005.) It has been shown that medial plantar grafts even in the form of pinch grafts are
effective in resurfacing palmar wounds. (Siman R.Medial Plantar Arch Pinch Grafts Are an
Effective Technique to Resurface Palmar and Plantar Wounds Ann Plast Surg 2004;53: 256–
260.) At follow-up all those with plantar skin grafts show excellent color and texture match
with adjacent palmar or plantar skin. The graft would be soft, supple, mobile and stable
without any pigmentation. Walking and weight bearing has been shown to be smooth.
Another example for choice of graft is decision on glabrous or non glabrous skin grafts.
Plantar defects that are to be grafted are reconstructed with split or full thickness skin grafts.
If non glabrous skin grafts are used some disadvantages which includes painfull
hyperkeratotic build up at the periphery of the grafts ocur. The long standing use of
glabrous skin grafts for plantar defects confirms the desirability functional advantage,
minimal morbidity of this technique. (Banis JC. Glabrous skin grafts for plantar defects. Foot
Ankle Clin 2001:6(4); 827-837).
4.2 Choice of donor site and its preparation
Donor sites for full-thickness skin grafts tend to be limited to areas over joint creases or
crevices where the donor site can be closed directly after graft harvest. For glabrous skin,
hypothenar donor area, wrist crease and plantar arc area are good donor sites. Skin may be
harvested from abdomen for facial defect repair, however the color and texture match may
be less desirable. Donor sites for the harvest of skin graft include the lumbar and gluteal
regions (thick skin), the thighs, and the arms (thin skin). The skin on the ventral, outer, and
dorsal aspects of the thigh is classed as intermediate thickness for the purposes of skin
grafting; an optimum harvest is 0.35 mm thick(Ostrovisky NV. Selection of the skin graft
thickness with regard to the structure of the donor site skin. Acta Chir Plast; 27: 145-51;
1985). The usable thickness of thigh skin graft varies froma minimum of 0.25 mm to a
maximum of 0.55 mm in most cases, though in elderly patients or steroid-damaged skin a
thinner graft needs to be taken.
In contrast to common sites, the scalp’s advantage has been seen primarily for cosmetically
satisfying repair of facial defects. An additional important reason for using the scalp as a
donor site for split-skin grafts is the patient’s postoperative comfort and mobility. Wound
healing is quick, the risk of infection is minimal, graft preparation and postoperative care
are relatively easy, and the scalp as a source of meshgrafts harbors a reasonably large area
for wound coverage. The site has only minimal interference with patients’ rehabilitation,
and later scar formation is rare. The donor site hidden under regrowing hair is invisible
(Weyandt GH, Bauer B, Berens N, Hamm H, Broecker EB. Split-thicknes skin grafting from
scalp: The hidden advantage.Dermatol Surg:35;1873-1879; 2009)
If possible use local anesthesia for donor site so that more likely to operate. Use plenty of
very dilute local anesthetic for example, donor site is anesthesized with 1% lidocaine with
epinephrine 1:100000 . In addition 10-30 cc of saline is added to produce turgor. The turgor
helps with anesthesia, provides hemostasis and reduces transection of hair follicles. If
possible use local anesthetic such as 0,4 % lignocaine with adrenalin and 10-30 cc of saline is
added to produce turgor to graft out the skin all over the donor site. This helps hemostasis
and reduces transection of hair follicles, when there is a need of hair follicle inclusion into
the graft. Any medication that is not essential should be stopped at least 1 week prior to
surgery. All smokers should be encouraged to cease cigarette smoking several days prior to
surgery and to continue this for at least the first postoperative week. The donor skin is
prepared and lubricated in the usual way, tensed using the skin graft boards and the graft
taken. Proper skin tensioning is important.

Skin Graft Harvesting and Donor Site Selection

31
4.3 Fixation techniques
Sutures, staples, or other adhesive agents can be used to affix the skin graft to the recipient
bed. he use of stitches is a common method of fixation but it is quite time consuming,
difficult to do in the split-thickness graft, very expensive and the stitches must be
removed.A “stent” dressing and even the ubiquitous subatmospheric pressure device are
intended means of preventing graft separation from the wound resulting from either shear
forces or subgraft fluid accumulations. (Hallock GG. Expanded applications for octyl-2-
cyanoacrylate as a tissue adhesive. Ann Plast Surg.;46:185–189; 2001) Human fibrin sealant
(FS) has been proven effective for skin grafting after burn. FS is used as a slow clotting spray
(4-5 IU thrombin /ml) (Mittermayr R, Wassermann E, Thurnher M, Simunek M, Redl H.Skin
graft fixation by slow clotting fibrin sealant applied as a thin layer. Burns:32:3; 305-311;
2006).
An alternative, especially applicable for large sheet grafts, would be to leave the graft
uncovered to allow frequent rolling of fluids from underneath. The use of surgical drape
placed over the graft has been recognised, but must be removed at the second or third
day[3]M.O. Yenidünya, E. Özdengill and I. Emsen, Split-thickness skin graft fixation with
surgical drape, Plast Reconstr Surg 106 (6) (2000), pp. 1429–1430. View Record in ScopusCited
By in Scopus (7) when the grafts are not well vascularized and this can lead to failure of the
graft. In convex areas skin graft fixation can be done by a simple tie-over dressing (Coban YK.
A novel tie-over dressing for circular defects: star tie-over .Burns:33(6);801-802; 2007)
4.4 Other parameters related to selection of donor site
Harvesting of an autograft results in a wound in healthy donor skin. Therefore several
techniques have been developed to reduce the required surface area of donor skin,
especially in FTSG applications of children. In order to obtain large enough FTSG and
accomplish primary donor site closure, a prior tissue expansion may be applied at the donor
site (Canter HI, Igde M, Vargel I, Ozgur F.Repeated tissue expansions on split-thickness skin
graft in a patient with neurocutaneous syndrome.J Craniofac Surg:18(3);699-703; 2007).
Some pactical methods are also present in taking grafts like reuse skin graft patches or using
freshly generated epithelium as a source of donor site. (Coban YK, Gumus N. Reuse of skin
graft patches fort he coverage of skin defects.J Burn Care Res:27(2);234-236; 2006) (Gumus
N, Coban YK.Freshly generated epithelium may be a donor site fort he coverage of deep
skin defects in the combined skin wounds.Burns:33(5);673-676; 2007).Main logics of these
applications are the presence of limited sources of donor sites and concerns on wounding a
healthy donor site.Looking for an alternative donor site scalp is a suitable location to achieve
STSG. If early repetetive harvesting from the same area is required such as in a burn
patients, shortening of healing time and patients mobility are great advantages for this
donor site .
4.5 Limitations of composite grafting
Composite grafts have limited dimentions and their usage for solving some challenging
clinical conditions are also limited. Their usual dimention is about 0,5 cm (width) x 3cm
(lenght). As they are dependent on recipient blood supply, grafts exceeding dimentions of
these limits can not survive. If a long strip graft is to be used, its width must not exceed 0,5
cm. (Coban YK, Geyik Y.An ideal donor site for postburn alar rim deficiencies: root of helix.
J Craniofac Surg: 21(4);1246; 2010).

Skin Grafts – Indications, Applications and Current Research

32
5. Future expectations
Numerous variations such as mesh grafts, cultured epithelial autografts (CEA)and
combined allo-autografts techniques have significantly enhanced the therapeutic spectrum
of traditional skin graft techniques. In the absence of a dermis, mature fibroblasts secrete
collagen into the altered pattern of a scar. The graft can fail to take when CEAs and
autografts are applied to a wound surface in poor condition without a dermis. Moreover,
there is a risk of poor epithelialization, due to the absence of a dermal component at the
recipient site. Therefore, a dermal equivalent is required to overcome this problem. issue
engineered skin is a significant advance in the field of wound healing. The translation from
scaffolds to instructive three dimentional dermal substitues is not a simple task. New skin
substitues for burn care are currently under development. They were developed due to
limitations associated with the use of autografts. These limitations include the creation of a
donor site which is at risk of developing pain, scarring, infection and /or slow healing.
More complex tissue-engineered skin substitues in which stroma, adipose tissue, capillaries
and neurons combined with epithelium are being developed. These products are often a
combination of cells, scaffolds and other factors.(Proulx S, Fradette J, Gavuin R, Larouche D,
Germain L.Stem cells of the skin and cornea: Their applications in regenerative medicine.
Curr Opin Organ Transplant 2010;dec 9.epub.) The application of these new products
necessiate generally two-three staged operations to obtain final results.(FIGURE 13) During
the past decade skin equivalents have been developed in order to reproduce epidermal and
dermal elements in vivo.
A number of approaches were taken in the development of a skin substitute. One solution
was to develop an acellular matrix complex that would guide the migration of fibroblasts
into a pattern that had dermal-like qualities. Another approach was to expand a small piece
of epidermis into a very large transplantable viable autologous-epidermal cell layer through
tissue culturing. The third approach was to develop a skin equivalent composed of both a




Fig. 13. Hypertrophic scarring due to flame burn injury of mandibular region (Left), well-
developed granulation after the application of hyalomatrix skin substitute (esterified
hyalurinic acid ) for three weeks following to excision of scarred tissues (right), final result
with thin STSG for epidermal replacement (centre).

Skin Graft Harvesting and Donor Site Selection

33
collagen matrix populated with viable fibroblasts and a dermal equivalent layer that was
covered with viable keratinocytes (epidermal layer). Most commercially available products
are based on polymer matrices derived from both natural and synthetic sources. The
majority of these products are designed to mimic the basic properties of the extracellular
matrix. The use of dermal substitutes is increasingly widespread but the outcomes of
substitute-asisted healing remain functionally deficient. There seems to be a long way to
obtain a perfect skin equivalance that mimicks all structures of dermis and epidermis both
aesthetically and functionally.
6. Conclusion
Skin grafting has become a technique that is routinely and sometimes preferentially
considered as skin replacement for burns, chronic ulcers, skin defects due to other etiologies.
In cases in which autologous grafts cannot be performed, skin substitutes have become an
attractive alternative. Autologous skin grafts are commonly considered as the gold standard
treatment. Availability of autologous grafts is a major obstacle, however, and the search for
a manufactured skin replacement seems to be continued.
7. References
[1] Banis JC. Glabrous skin grafts for plantar defects. Foot Ankle Clin 2001:6(4); 827-837
[2] Blair VP, Brown JB: Use and uses of large split skin grafts of intermediate thickness. Surg
Gynecol Obstet 49: 82-97, 1929.
[3] Canter HI, Igde M, Vargel I, Ozgur F.Repeated tissue expansions on split-thickness skin
graft in a patient with neurocutaneous syndrome. J Craniofac Surg 2007:18(3);699-
703.
[4] 4-Coban YK, Gumus N. Reuse of skin graft patches fort he coverage of skin defects. J
Burn Care Res 2006:27(2);234-236.
[5] Coban YK. A novel tie-over dressing for circular defects: star tie-over .Burns
2007:33(6);801-802.
[6] Coban YK, Geyik Y.An ideal donor site for postburn alar rim deficiencies: root of helix. J
Craniofac Surg 2010: 21(4);1246.
[7] Goullian D.A new economical dermatome Plast Reconst Surg 42: 85; 1968.
[8] Gumus N, Coban YK. Freshly generated epithelium may be a donor site for the coverage
of deep skin defects in the combined skin wounds.Burns 2007:33(5);673-676.
[9] Hallock GG. Expanded applications for octyl-2-cyanoacrylate as a tissue adhesive. Ann
Plast Surg. 2001;46:185–189.
[10] Kasai K.Eyelash resonstruction with strip composite eyebrow graft. Head and Neck
Surg 2008:60(6);649-651.
[11] Lahiri K.Evolution and evaluation of autologous mini punch grafting in vitiligo..Indian
J Dermatol 2009:54(2); 159-167.
[12] Landau A, Hudson DA, Adams K, Geldenhuys S, Pienaar C.Full-thickness skin grafts:
Maximising graft take using negative pressure dressings to prepare the graft bed.
Ann Plast Surg 2008:60(6); 661-666.
[13] Lever WF: Histology of skin. pp 9-45. In Lever WF, Shaumburg-Lever G (eds) :
Histhopathology of the skin 5th ed.JB Lippincott, Philadelphia 1975.

Skin Grafts – Indications, Applications and Current Research

34
[14] Meaume S.Methods of non surgical debridement of wounds in 2011.2011:Soins 752:44-
47.
[15] Mittermayr R, Wassermann E, Thurnher M, Simunek M, Redl H.Skin graft fixation by
slow clotting fibrin sealant applied as a thin layer. Burns 2006:32:3; 305-311.
[16] Ostrovisky NV. Selection of the skin graft thickness with regard to the structure of the
donor site skin. Acta Chir Plast 1985; 27: 145-51.
[17] Padgett EC. Skin grafting of the burned patient. Plast Reconstr Surg 1946.1947 jul 2(4):
368-74.
[18] Paletta CE, Pokorny JJ, Rumbolo P. Skin grafts. In: Mc- Carthy JG, ed. Plastic Surgery.
Philadelphia: Saunders Elsevier; 2006:293–316.
[19] Peeters R, Hubens A, The mesh skin graft – true expansion rate – Burns, vol. 14 (3), pp.
239-24 , 1988.
[20] Proulx S, Fradette J, Gavuin R, Larouche D, Germain L.Stem cells of the skin and
cornea: Their applications in regenerative medicine. Curr Opin Organ Transplant
2010;dec 9.epub.
[21] Raff T, Hartmann B, Wagner H, Germann G. Experience with the modified Meek
technique. Acta Chir Plast. 1996; 38 (4): 142 - 146.
[22] Reverdin JL: De la greffe epidermique. Arch Gen Med 19:276;555, 703, 1972.
[23] Rudolph R, Ballantyne DL. Skin grafts. In: McCarthy JG, ed. Plastic Surgery.
Philadelphia: Saunders; 1990:221–274.
[24] Sams HH, McDonalds MA, Stasko T.Usefull adjunct to harvest split-thickness skin
grafts. Dermatol Surg 2004:30(12pt 2): 1591-1592.
[25] Shoul M.Skin grafting under local anesthesia using a new safety razor Am J Surg
112.959,1966.
[26] Siman R.Medial Plantar Arch Pinch Grafts Are an Effective Technique to Resurface
Palmar and Plantar Wounds Ann Plast Surg 2004;53: 256–260.
[27] Snow JW. Safety razor dermatome Plast Reconstr Surg 41: 184, 1968.
[28] Taner C, Vabdeput JF and Olley JF. The mesh skin graft, Plast Reconstr Surg 34 (1964),
pp. 287–292. and Kreis RW, Mackie DP, Hermans RP and Vloemans AR.
Expansion technique for skin grafts: comparison between mesh and Meek island
(sandwiched-) grafts, Burns 20: 1994; 39–42.
[29] Tiersch C : Über Hautverplanzung. Verh Dtsch Ges Chir 15-17, 1886.
[30] Yıldırım S, Akan M, Akoz T, Tanoglu B.Preputium: an overlooked skin graft donor
site. Ann Plast Surg 2001:46(6);&30-634.
[31] Weyandt GH, Bauer B, Berens N, Hamm H, Broecker EB. Split-thicknes skin grafting
from scalp:The hidden advantage.Dermatol Surg 2009:35;1873-1879.
[32] Wu LC, Goutlieb LJ. Glabrous Dermal Grafting: A 12-Year Experience with the
Functional and Aesthetic Restoration of Palmar and Plantar Skin Defects
Plast.Reconstr. Surg. 116: 1679, 2005.

3
Indications of Skin Graft
Abdou Darwish
Minia University
Egypt
1. Introduction
The skin is the largest organ of the human body and it known as the integument or
integumentary system because it covers the entire outside of the body. The skin consists of
two main layers: the outer layer, or epidermis, which lies on and is nourished by the thicker
inner layer, or dermis.. These two layers are approximately 0.04–0.08 in (1–2 mm) thick. The
epidermis consists of an outer layer of dead cells called keratinocytes, which provide a
tough protective coating, and several layers of rapidly dividing cells just beneath the
keratinocytes. The dermis contains the blood vessels, nerves, sweat glands, hair follicles, and
oil glands. The dermis consists mainly of connective tissue, which is largely made up of a
protein called collagen. Collagen gives the skin its flexibility and provides structural
support. The fibroblasts are the main cell type in the dermis and make collagen. Skin varies
in thickness in different parts of the body; it is thickest on the palms and soles of the feet,
and thinnest on the eyelids. In general, men have thicker skin than women, and adults have
thicker skin than children. After age 50, the skin begins to grow thinner again as it loses its
elastic fibers and some of its fluid content. A skin graft is used permanently replace
damaged missing skin or provide a temporary wound covering. Skin is necessary because it
protects the body against
Fluid loss, bacteria or virus invasion, and aids in temperature regulation. Skin that is
damaged extensively by burns or non-healing wound can compromise an individual’s
health and well-being. Skin grafting is the next step on the reconstructive ladder for the
closure of a wound that cannot be closed primarily. Skin grafts are classified as either
split-thickness or full-thickness, depending on the amount of dermis included in the
graft.
A partial or split-thickness skin graft (STSG) contains a variable thickness of dermis, while a
full-thickness skin graft (FTSG) contains the entire dermis. Split-thickness skin grafts are
further categorized as thin (0.005-0.012 in), intermediate (0.012-0.018 in), or thick (0.018-0.030
in) based on the thickness of the graft harvested. Skin grafting serves two purposes: reduce
the course of treatment and improves function and appearance of the recipient area.
2. Types of skin grafts 
The term "graft" by itself commonly refers to either an allograft or an auto graft. An
autograft is a type of graft that uses skin from another area of the body but there has to be
enough undamaged skin available and the patient has to be healthy

Skin Grafts – Indications, Applications and Current Research
36
enough to undergo surgery. An allograft uses skin obtained from another human being,
Donor skin from cadavers is frozen, stored, and available for use as an allograft. Skin taken
from an animal (usually a pig) is called a xenograft because it comes from a nonhuman
species. Allograft and xenograft provide only a temporary covering because of rejection by
the patient’s immune system within seven days. The allograft or xenograft must then be
replaced with an auto graft.
2.1 Split thickness grafts
The most important part of any skin graft procedure is proper preparation of the wound.
Skin grafts will not survive on tissue with a limited blood supply (cartilage, bone or
tendons) or tissue that has been damaged by radiation treatment. The wound must be free
of any dead tissue, foreign matter, or bacterial contamination. After the patient has been
anesthetized, the surgeon prepares the wound by rinsing it with saline solution or a diluted
antiseptic (Betadine) and debrides any dead tissue. In addition, the surgeon stops the flow
of blood into the wound by applying gentile pressure, tying off blood vessels, or
administering a medication (epinephrine) that causes the blood vessels to constrict.
Following preparation of the wound, the surgeon then harvests the tissue for grafting. A
split-thickness skin graft involves the epidermis and a little of the underlying dermis; (the
donor site usually heals within several days). The surgeon first marks the outline of the
wound on the skin of the donor site, enlarging it by 3–5% to allow for tissue shrinkage. The
surgeon uses a dermatome (a special instrument for cutting thin slices of tissue) to remove a
split-thickness graft from the donor site. The wound must not be too deep if a split-thickness
graft is going to be successful, since the blood vessels that will nourish the grafted tissue
must come from the dermis of the wound itself. The graft is usually taken from an area that
is ordinarily hidden by clothes such as the buttock or inner thigh and applied on the wound.
Gentle pressure from a well-padded dressing is then applied, or a few small sutures used to
hold the graft in place. A sterile non adherent dressing is then applied to the raw donor area
for approximately three to five days to protect it from infection.
2.2 Full thickness grafts.
Full-thickness skin grafts may be necessary for more severe burn injuries, trauma and
excision of malignancy. These grafts involve both layers of the skin. Full-thickness auto
grafts are more complicated than partial-thickness grafts, but provide better contour, natural
color, and contract less at the grafted site. The back and the abdomen are common donor
sites for full-thickness grafts. A full-thickness graft is removed from the donor site with a
scalpel rather than a dermatome. After the surgeon cuts around the edges of the pattern
used to determine the size of the graft, the skin is lifted with a special hood and the fatty
tissue is trimmed. The graft is then placed on the wound and secured in place with
absorbable sutures.
2.3 Composite skin graft
A composite skin graft is sometimes used. A composite skin graft consists of combinations
of skin and fat, skin and cartilage, or dermis and fat. Composite grafts are used in patients
whose injuries require three-dimensional reconstruction. For example, a wedge of ear
containing skin and cartilage can be used to repair the nose.

Indications of Skin Graft
37
3. Indications of skin graft
3.1 Deep fullthickness burns
Deep full thickness burns destroy the skin and damage underlying tissues and are the most
common indication For split thickness skin grafts (fig. 1) where, the skin is destroyed to its
full depth, in addition to damage done to underlying tissues, and Deep full thickness burns
must be covered as soon as possible to prevent infection and fluid loss. Wounds that are left
to heal on their own (secondary intention) can contract and result in serious and painful
scarring and actually prevent normal limb movement.





Fig. 1. Deep full thickness burns of both lower limbs and after reconstruction with STSG.
3.2 Post traumatic skin loss
Friction burns ((fig. 2) and degloving injuries (fig. 3,4) due to car accident and other
traumas which leads to full thickness skin loss are indication for split thickness graft. In
cases of friction burns the area of skin loss should be washed thoroughly with sterile
saline to make sure that the recipient site is clean and ready for grafting. If the wound still
remains contaminated, it should be dressed until complete cleanliness of the wound is
obtained.



 


Fig. 2. Friction burns of the lateral aspect of the lower leg with full thickness skin loss and
after reconstruction with STSG.

Skin Grafts – Indications, Applications and Current Research
38


Fig. 3. Degloving injury of the right leg after debridement and after reconstruction by STSG




Fig. 4. Degloving injury of the right leg before and after debridement and reconstruction by
STSG

Indications of Skin Graft
39
3.3 During surgery
After release of post burn contractures and after reconstruction by local flaps such as a
transposition or bipedicled flap requires grafting to close the donor site (fig. 5-8). Also
excision of large tumor usually need skin graft to reconstruct the resultant defect.



Fig. 5. A) Post burn breast contraction of both breasts and after release of breast contraction

Fig. 5. B) After application of STSG to the row area of lower chest and upper abdominal wall


Fig. 6. Exposed tibia and after reconstruction by bipedicled flap and STSG applied to the
donor site of flap

Skin Grafts – Indications, Applications and Current Research
40

Fig. 7. Exposed tibia and after reconstruction by bipedicled flap and STSG applied to the
donor site of the flap.



 
Fig. 8. A) Exposed tibia and after reconstruction by transposition flap and STSG is applied to
the donor site of the flap.


Fig. 8. B) the appearance of the graft after one year.