Atlas of Primary Care Procedures, 1st Edition

Dermatology

25

Basic Z-Plasty

Historically, Z-plasty has been a commonly taught and used technique in plastic surgery. Many variations of Z-plasty have been developed, but this chapter focuses on the basic (60-degree) Z-plasty technique. The procedure uses the transposition of two triangular flaps to produce a Z-shaped wound. The main indication for performing Z-plasty is to change the direction of a wound so that it aligns more closely with the resting skin tension lines. Because the technique increases the length of skin available in a desired direction, Z-plasty also is used to correct contracted scars across flexor creases. The 60-degree Z-plasty lengthens the scar (or available length in a certain direction) by 75%.

When considering the performance of a Z-plasty, some physicians theoretically object to the creation of a wound that is three times as long as the original wound (i.e., the two diagonal arms are as long as the central wound). Although the creation of long wounds is generally discouraged, a well-designed Z-plasty can significantly improve the cosmetic and functional outcome. Z-plasty can be performed on a fresh wound that is counter to the resting skin tension lines, although some experts recommend simple closure of the wound and then Z-plasty at a later date to revise scars that are problematic.

The technique of Z-plasty is easy to understand, but it requires some skill and practice. Physicians with the opportunity to frequently perform Z-plasty observe generally favorable functional and cosmetic outcomes.

INDICATIONS

  • Revision of contractures or scars that cross flexor creases and result in bowstring-type scars (e.g., vertical scars over the flexor creases of the proximal interphalangeal joints of the hands)
  • Revision of scars that transverse across concavities (e.g., across a deep nasolabial fold, a vertical scar that transverses between the lower lip and the chin)
  • Redirection of wounds that are perpendicular to the lines of least skin tension (i.e., reorient to a direction that will produce a cosmetically superior result)
  • Creation of wound irregularity (i.e., improved cosmetic results from a line that is “broken-up” or zig-zag versus a long, straight line that is less appealing)
  • Repositioning of poorly positioned tissues that produce a trap-door effect (i.e., rearranging a circular scar that is causing the central tissue to raise upward)

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PROCEDURE

The original (vertical) wound or scar (AB) is perpendicular to the lines of least skin tension.

 

(1) The vertical wound or scar (AB) is perpendicular to the lines of least skin tension.

Draw and incise the diagonal lines, with one arm on each side of the original wound. The diagonal lines AC and BD are the same length as the original line AB, and they are 60 degrees away from the center line. The left triangular flap is labeled F1, and the right flap is labeled F2.

 

(2) Draw and incise diagonal lines, AC and BD, which are the same length as the original scar (AB) and are 60 degrees away from the center line.

PITFALL: Place the side arms on opposite sides of the central wound. Novice physicians occasionally make the error of performing their first Z-plasty with the arms on the same side of the central wound.

PITFALL: Many physicians unintentionally incise the diagonal lines at 45-degree angles, rather than 60-degree angles. Flaps in a 45-degree Z-plasty are easier to transpose but only rotate the direction of the original defect by 60 to 70 degrees (rather than 90 degrees with a 60-degree Z-plasty).

Undermine the flaps and the surrounding skin in the level of the upper fat (i.e., below the dermis).

 

(3) Undermine the flaps and the surrounding skin in the level of the upper fat below the dermis.

PITFALL: Failure to undermine extensively makes the transposition very difficult. Liberal undermining is beneficial.

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Transpose the flaps. F2 now appears on top, and F1 now appears on the bottom. The new line in the center (CD or FE) aligns with the resting skin tension lines.

 

(4) Transpose the flaps so that F2 appears on the top and F1 appears on the bottom.

PITFALL: Handle the flaps gently, grasping the skin with skin hooks or Adson forceps without teeth. Many physicians transpose the flaps with toothed forceps, causing tears or damage to the flaps and adding unnecessary scarring.

Place a central anchoring stitch holding the two flaps in position.

 

(5) Place a central anchoring stitch holding the two flaps in position.

Place corner stitches in the corners of each flap, and then place the stitches on the ends of the diagonals (AC and BD). Keep the stitches on the diagonals to a minimum, and do not place the diagonal stitches near the corner.

 

(6) Place corner stitches in the corners of each flap, and place stitches on the ends of the diagonals (AC, BD).

PITFALL: Almost all 60-degree Z-plasties performed on human skin result in some pouching upward at the base of the flap after transposition. This upward bunching of tissue, or dog-ear formation, occurs almost universally, and should not be of great concern. Most dog-ear formations are caused by the marked rotation of the tissue, and they will flatten with time, resulting in a good cosmetic outcome.

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A contracted scar commonly results from wounds that traverse the flexor creases on the fingers (Figure 7A). Excise the scar, and then draw and excise the lateral arms (Figure 7B). The center of the final wound now runs parallel to the resting skin tension lines (Figure 7C).

 

(7) Basic Z-plasty of a contracted scar.

A wound that crosses the nasolabial fold (Figure 8A) may result in an unsightly, contracted, bowstring scar. The wound can be redirected with a Z-plasty. Draw and excise the lateral arms (Figure 8B). The center of the final wound follows the center of the nasolabial fold (Figure 8C). F1 and F2 represent the flaps before and after transposition, respectively.

 

(8) Basic Z-plasty of a wound that crosses the nasolabial fold.

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CODING INFORMATION

See coding list in Chapter 26.

INSTRUMENT AND MATERIALS ORDERING

Instruments are listed in Appendix A. Suggested suture removal times are listed in Appendix C, and a suggested anesthesia tray that can be used for this procedure is listed in Appendix G.

BIBLIOGRAPHY

Borges AF, Alexander JE. Relaxed skin tension lines, Z-plasties on scars, and fusiform excision of lesions. Br J Plast Surg 1962;15:242–254.

Dzubow LM. Z-plasty mechanics [Comment]. J Dermatol Surg Oncol 1994;20:108.

Gahankari D. Z-plasty template: an innovation in Z-plasty fashioning. Plast Reconstr Surg 1996;97:1196–1199.

Hudson DA. Some thoughts on choosing a Z-plasty: the Z made simple. Plast Reconstr Surg 2000;106:665–671.

Johnson SC, Bennett RG. Double Z-plasty to enhance rhombic flap mobility. J Dermatol Surg Oncol 1994;20:128–132.

Lesavoy MA, Weatherley-White RCA. The integument. In: Hill GJ, ed. Outpatient surgery, 3rd ed. Philadelphia: WB Saunders, 1988:123–148.

McCarthy JG. Introduction to plastic surgery. In: McCarthy JG, ed. Plastic surgery. Philadelphia: WB Saunders, 1990:1–68.

Micali G, Reali UM. Scars: traumatic and factitial. In: Parish LC, Lask GP, eds. Aesthetic dermatology. New York: McGraw-Hill, 1991:84–95.

Robson MC, Zachary LS. Repair of traumatic cutaneous injuries involving the skin and soft tissue. In: Georgiade GS, Georgiade NS, Riefkohl R, Borwick WJ, eds. Textbook of plastic, maxillofacial, and reconstructive surgery, 2nd ed. Baltimore: Williams & Wilkins, 1987:129–140.

Sclafini AP, Parker AJ. Z-plasty. Emedicine Available at http://www.emedicine.com/ENT/topic652.htm

Stegman SJ, Tromovitch TA, Glogau RG. Basics of dermatologic surgery. Chicago: Year Book Medical Publishing, 1982.

Stegman SJ. Fifteen ways to close surgical wounds. J Dermatol Surg 1975;1:25–31.

Zuber TJ. The illustrated manuals and videotapes of soft-tissue surgery techniques. Kansas City: American Academy of Family Physicians, 1999.