Living with Dead Spaces: Closing Complex Posterior Midline Defects with Midline-Based Perforator Flaps.

Sir:

We read with interest the article by Datli et al.[1] on closure of defects with large dead spaces on the posterior trunk. The authors made a valuable contribution with their technique for closure of these defects. They stress that complete debridement and obliteration of dead space with well-vascularized tissue should be one of the primary concerns to avoid secondary complications, especially infection. Traditionally, muscle flaps have been used to close posterior trunk defects with dead spaces because their rich vascularity enhances wound healing and assists in elimination of residual infection. The pliable and bulky muscle easily obliterates dead spaces.[1] The authors followed the general reconstructive principles for posterior trunk defects as formulated by Ramasastry et al.,[2] which are:

Control of infection with appropriate systemic antibiotic agents

Local wound care

Extensive debridement of all devitalized tissue

Reestablishment or maintenance of skeletal stability

Preservation of neural function

Obliteration of dead space with well-vascularized tissue

Early definitive coverage of the defect to minimize infective complications.[2]

The authors used a free-style and buried deepithelialized propeller flap to obliterate dead space and obtained stable closure in their patients. We agree with the authors that successful closure of posterior trunk defects can be challenging when dead spaces are large, infected, or located in the middle of the posterior trunk. Five of their 7 patients had midback defects.

Perhaps the most challenging posterior midline defects to treat are those with infected and exposed spinal hardware. Although this was not mentioned by the authors, we reported on the successful use of the sensate medial dorsal intercostal artery perforator (MDICAP) flap for closure of such defects.[3] This flap has its pivot point at the midline. A tension-free wound closure was obtained by suturing the flap into the wound defect. Spinal hardware was not removed. The mean follow-up in our series of 9 patients with 10 flaps was 65 months (range, 7–106). Only 1 patient developed an infection in the operated area that occurred 81 months postoperatively.

Unlike the authors, we did not use a free-style propeller flap. Based on our anatomic study, a perforator flap was elevated on the MDICAP.[4] Inclusion of the accompanying cutaneous nerve resulted in protective sensibility in the reconstructed area.

We tried to adhere to the principles formulated by Ramasastry et al.[2] However, it was difficult to obtain obliteration of the large dead spaces due to extensive debridement and exposed hardware. The use of a negative pressure device reduced the 3-dimensional complexity of the wound, and therewith dead space. Nevertheless, some dead space remained and could not be obliterated with the use of the MDICAP flap (Fig. 1). The long-term results of our study may indicate that it is not necessary to obliterate all dead space completely to prevent infection.

Fig. 1.

A complex midline defect with infected and exposed spinal hardware (A) was successfully closed using a sensate MDICAP flap (B) without obliteration of dead spaces.