65 Skin Grafts & Local Flaps Flashcards
Describe the concept of the “reconstructive ladder.”
Describe the concept of the “reconstructive ladder.”
The goal of surgical management of a wound aims to obtain rapid wound closure utilizing the simplest method, while creating the best functional and cosmetic outcome. The “reconstructive ladder” concept helps the reconstructive surgeon assess the complexity of the treatment required, beginning with the simplest modality and progressing in difficulty from there (Box 65-1).
What are the three histologic layers of the skin?
What are the three histologic layers of the skin?
The skin is composed of the epidermis, the dermis, and the subcutaneous connective tissue. The epidermis is composed of keratinizing stratified squamous epithelium and is separated from the dermis by a basement membrane. The dermis is subdivided into a thin papillary dermis overlying a thicker reticular dermis.
What is a skin graft?
What is a skin graft?
A skin graft is an island of epidermis with varying thicknesses of dermis, which has been surgically removed from a donor site and transferred to a recipient site. The blood supply to the skin graft is dependent on the vascularity of the recipient site.
When should a skin graft be utilized?
When should a skin graft be utilized?
Skin grafts are best utilized to address wounds that cannot reasonably be reconstructed with primary closure or a local flap. Wound size or location may often prohibit primary closure or the use of local flaps. To obtain the best cosmetic outcome the graft should be harvested from a site closely matching the color and texture of the skin surrounding the wound.
What two ways can be used for harvesting skin grafts?
What two ways can be used for harvesting skin grafts?
Skin grafts are harvested as full thickness or split thickness. Full-thickness skin grafts (FTSG) consist of epidermis and the full thickness of dermis. They are usually harvested deep to the dermis and within the superficial subcutaneous plane. Split-thickness skin grafts (STSG) consist of epidermis and a variable portion of underlying dermis. They are usually harvested utilizing a dermatome.
What factors will most affect skin graft viability?
What factors will most affect skin graft viability?
Several factors directly influence skin graft viability. These include the vascularity of the recipient site, vascularity of donor graft tissue, contact between graft and recipient site, and certain systemic illness. Irradiated tissue, exposed bone or cartilage, infected tissue, or bleeding wounds, tend to be unfavorable for skin graft take.
What are the phases of skin graft survival?
What are the phases of skin graft survival?
Skin grafts initially survive by the diffusion of nutrition from serum at the recipient site through a process termed plasma imbibition. Between days three and seven, there is reestablishment of blood flow between preexisting graft capillaries and recipient end capillaries, in a phase termed inosculation. Revascularization begins at approximately day 4 and is characterized by the ingrowth of new vessels into the graft.
What are the advantages and disadvantages of a full-thickness skin graft?
What are the advantages and disadvantages of a full-thickness skin graft?
Full-thickness grafts provide a better color match, better texture match, and will undergo less contraction than split-thickness grafts. The disadvantage is reduced survival rate and longer healing time.
What are the advantages and disadvantages of a split-thickness skin graft?
What are the advantages and disadvantages of a split-thickness skin graft?
A split-thickness skin graft will have increased viability due to greater capillary exposure on the undersurface of the graft. This permits greater absorption of nutrients from the wound bed. Also, because STSGs contain less tissue, revascularization occurs more quickly. The main disadvantage is that STSGs often result in poor texture and color match.
What are the important points for postoperative care of skin grafts?
What are the important points for postoperative care of skin grafts?
Skin graft dressings should aim to immobilize the graft on the recipient bed. Often this immobilization is accomplished with bolsters, made of Xeroform or petroleum gauze. The dressing should remain in place for 5 to 7 days to enable adequate graft adherence to take place and help prevent desiccation.
How should a skin graft donor site be managed?
How should a skin graft donor site be managed?
Full-thickness donor sites are closed primarily, when possible. Split-thickness skin graft donor sites are best treated with an occlusive dressing. Studies have shown that a moist, clean, healing environment allows wounds to heal more quickly.
What are the four main mechanisms by which skin grafts fail?
What are the four main mechanisms by which skin grafts fail?
The most common mechanisms of failure include: (1) inadequate wound bed vascularity, (2) shearing forces that separate the graft from the bed and prevent revascularization, (3) hematoma or seroma formation that prevents contact of the graft to the bed, and (4) infection.
What is a local cutaneous flap?
What is a local cutaneous flap?
A local cutaneous flap is an area of skin and subcutaneous tissue with direct vascular supply that is transferred to a site located adjacent to or near the flap. By contrast, a graft does not carry its own blood supply.
What are relaxed skin tension lines, and why are they important?
What are relaxed skin tension lines, and why are they important?
Relaxed skin tension lines (RSTL) are lines intrinsic to aging skin. They manifest as creases and wrinkles orientated perpendicular to the underlying facial mimetic musculature. In planning skin excisions, wound closures, or local flaps, it is desirable to orient the resulting closure or scar parallel to RSTLs. Wounds oriented parallel to RSTLs will camouflage nicely, and have minimal wound closure tension, thus resulting in a less apparent scar.
How and why would a surgeon perform undermining?
How and why would a surgeon perform undermining?
Undermining the skin reduces wound closure tension by distributing skin deformation. During undermining, the skin and some portion of subcutaneous fat are released from the underlying fascia. The lysis and release of vertical attachments between the dermis and subcutaneous tissue allows the skin to slide more freely over the subcutaneous tissue.
How are cutaneous flaps classified?
Cutaneous flaps are commonly classified according to their blood supply, configuration, location, or method of transfer. When characterizing by blood supply, local flaps can be based on a random or an axial pattern. Random flaps are based on the subdermal plexus and do not include a named blood vessel. An axial flap utilizes a dominant and named vessel for its primary vascularity. The paramedian forehead flap, based on the supratrochlear artery, is a commonly utilized axial pattern flap.
How are local flaps classified by method of transfer?
Pivotal flaps and advancement flaps are commonly utilized local flaps. An advancement flap has a linear configuration, and is advanced into a defect (Figure A). Because they involve stretching the skin of the flap, they work best in areas of significant skin laxity. Pivotal flaps involve pivoting the tissue around a fixed point at the base of the pedicle (Figure B). Examples of pivotal flaps include rotation, transposition, and interpolated style flaps.
Figure: A, B. Schematic representation of local flaps. Illustrated are the unilateral advancement, bilateral advancement, and rotational flaps. The flap length should be approximately 4 times the diameter of the defect.
How does a transposition flap differ from an interpolated flap?
How does a transposition flap differ from an interpolated flap?
A transposition flap is rotated over a segment of normal skin to be placed at an adjacent recipient site. Two commonly utilized transposition flaps are the rhombic flap and the bilobed flap (below). By contrast, the base of an interpolated flap is not contiguous with the defect. This arrangement creates a pedicle that crosses over intervening tissue. A second-stage procedure is needed for division and inset of the pedicle. An example of an interpolated flap is the paramedian forehead flap.
FIGURE: Bilobed transposition flap used to close a nasal defect.
**What three changes will a Z-plasty create in a scar contracture?**
What three changes will a Z-plasty create in a scar contracture?
A Z-plasty (Figure 65-4) is designed with three limbs of equal length that form two triangular flaps. The two triangular flaps represent transposition flaps. The tips of the triangles represent angular flaps that are transposed with each other. This technique is useful to: (1) interrupt the scar linearity, (2) lengthen a scar contracture, and (3) change the orientation of a scar/contracture.
Figure: A vertical scar is depicted on the left; 60° Z-plasty flaps are designed (a and b). After transposition, the central limb is lengthened and redirected, and the final scar is broken into three limbs (right).
