Z-plasty is one of many techniques for scar revision and camouflage. Z-plasty is a type of transposition flap that incorporates qualities of advancement and rotation flaps into its design. Whether used alone or in conjunction with other scar-camouflage techniques, Z-plasty is a versatile maneuver that, when mastered, provides aesthetically pleasing results. [1, 2]
In 1856, Denonvilliers first described the Z-plasty technique as a surgical treatment for lower lid ectropion. The first reference to this technique in American literature was in 1913, by McCurdy, as treatment for contracture at the oral commissure. Limberg, in 1929, provided a more detailed geometric description. Numerical data showing optimal angles and length relationships of Z-plasty limbs are credited to Davis (1946).
The image below depicts a Z-plasty.
Z-plasty is an especially useful technique when dealing with a scar that crosses relaxed skin tension lines. Simple redirection of the central limb into these lines can provide adequate camouflage. The redistribution of tension on the wound provided by Z-plasty can be very helpful when dealing with a contracted scar or with a scar near aesthetic units, such as the medial canthus or oral commissure.
Z-plasty is an effective method of wound irregularization. Since straight-line scars draw attention easily, multiple Z-plasties can break up the scar into smaller units, making the scar less noticeable.
Other uses of Z-plasty are as follows:
Limiting/preventing contracture of linear scars, especially when they cross the border of a facial aesthetic unit (eg, vermillion border) or when scars cross a concave surface (eg, the medial canthus)
Changing scar length (eg, scar contracture of lip, eyelid, or neck)
Changing scar vector (eg, repositioning a scar across the nasolabial fold)
Repositioning malposed tissues (useful for "trapdoor" or "pin-cushion" defects)
Effacing web/release contracture (similar to first listed use)
Closing cutaneous defects (eg, large oval defects, pharyngocutaneous fistulae)
Correcting stenosis (eg, tracheostoma, nares, external auditory canal) using single or multiple Z-plasties 
Transposing healthy tissue to close a fistula (eg, tracheostoma closure after irradiation)
Z-plasty requires a proper skin thickness. A flap with too much subcutaneous tissue is difficult to position because of limited rotation. A thin flap contracts readily and is unattractive. Ideally, a plane developed between the subdermal plexus and the subcutaneous fatty tissue provides support but is not restrictive in the degree of rotation afforded.
When designing a local flap, consider any factor that may compromise expected results. Attempt to identify health risks that affect vascular supply to the skin (eg, atherosclerotic heart disease, diabetes, smoking, collagen vascular disease, prior irradiation, anticoagulation). A history of poor wound healing, hypertrophic scarring, or keloid formation is a relative contraindication to Z-plasty.