Invited Discussion

Thin, cutaneous flaps inarguably have an important role in the treatment of burn contractures, as they do not obliterate anatomic landmarks, will not by themselves impede joint motion, and have virtually eliminated the need for splinting and prolonged rehabilitation.[1] Eo et al. have here reported a single case where, after release of a combined perineal and groin burn scar contracture, transposition of an island pedicled DIEP flap provided the necessary coverage, with the intent of capturing the above mentioned advantages as enumerated.

A recognized impediment to the universal adoption of muscle perforator flaps, especially true in the Western hemisphere, is the high incidence of obesity. This makes these flaps, if unaltered, too bulky, and the dissection itself extremely tedious, if not impossible.[2] To circumvent this omnipresent concern, these authors, after elevating the flap, performed an immediate thinning under loupe magnification, separating the superficial from deep adipose layers and discarding the latter, while preserving the fat around the nutrient perforator itself. Koshima et al.[3] actually first reported use of this same donor territory, with the successful transfer of “thin,” paraumbilical, perforator-based free flaps in 1992. A year later, Akizuki et al.[4] corroborated this, using free, “thin,” rectus abdominis flaps. This case report is an important extension of this idea, capturing an additional advantage in that, as a local pedicled flap, the risks of microsurgery are avoided.

Eo et al. are somewhat misleading in the inclusion of the term “microdissection” in their title. Although their flap was made thin, the microdissection technique, as introduced by Kimura,[5] [6] was intended to prepare very “thin” muscle perforator flaps. In the latter's approach, an operating microscope was used for an intra-adiposal layer dissection begining at the level of the deep fascia, to remove the adipose tissue around the perforator until it reaches the subdermal plexus. The course of these perforators has a characteristic anatomic pattern of branches in the deep adipose layer, varying according to the donor site,[6] [7] although fortuitously in the DIEP flap, they run relatively straight toward the subdermal plexus after arising from the main trunk that pierces the deep fascia. [Note, on the contrary, that this pattern of branching is multidirectional above the deep fascia for the anterolateral thigh flap, which would make “thinning” by gross scissor dissection dangerous.] Even with the greater care afforded by microdissection, it should be recognized that total flap viability can be jeopardized by any form of immediate flap thinning.[8]

These authors should be applauded for introducing another role for the reliable DIEP flap as a pedicled flap that avoids the inhrent risks of any microanastomosis. They have further corroborated the definitive role of muscle perforator flaps after burn contracture release, here allowing preservation of abdominal-wall muscle function in a woman of child-bearing age. It must be reiterated that flap thinning can have advantages, but is more risky if done immediately. The microdissection of a perforator flap is a distinct technical entity that is a more precise and tedious maneuver. The good result obtained in this case demonstrates that the increased risk and degree of difficulty, if “true” microdissection had been performed, were not indicated.

REFERENCES

• 1 Hallock G G. A history of the development of muscle perforator flaps and their specific use in burn reconstruction.  J Burn Care Rehab. 2004;  25 366-373
• 2 Hallock G G. Have we found an ideal soft-tissue flap? An experience with 672 anterolateral thigh flaps (Discussion).  Plast Reconstr Surg. 2002;  109 2227-2230
• 3 Koshima I, Moriguchi T, Soeda S, Tanaka H, Umeda N. Free thin paraumbilical perforator-based flaps.  Ann Plast Surg. 1992;  29 12-17
• 4 Akizuki T, Hrii K, Yamada A. Extremely thinned inferior rectus abdominis free flap.  Plast Reconstr Surg. 1993;  91 936-941
• 5 Kimura N. A microdisseected thin tensor fasciae latae perforator flap.  Plast Reconstr Surg. 2002;  109 69-77
• 6 Kimura N, Satoh K, Hsaka Y. Microdissected thin perforator flaps: 46 cases.  Plast Reconstr Surg. 2003;  112 1875-1885
• 7 Kimura N, Stoh K, Hasumi T, Otsuka T. Clinical applications of the free thin anterolateral thigh flap in 31 consecutive patients.  Plast Reconstr Surg. 2001;  108 1197-1208
• 8 Alkureishi L WT, Shaw-Dunn J, Ross G H. Effects of thinning the anterolateral thigh flap on the blood supply to the skin.  Br J Plast Surg. 2003;  56 401-408