Challenging the Dogma of Dead Space Obliteration With Muscle Flaps in Deep Spinal Surgical Site Infections.

Background: A deep surgical site infection (SSI) after spinal surgery is a serious complication. The defect formed is often a complex 3-dimensional dead space due to tissue loss, frequently containing spinal hardware. Traditionally, obliteration of that dead space is performed with the use of muscle flaps. We challenge this dogma in reconstructive surgery by using the medial dorsal intercostal artery perforator (MDICAP) flap as an alternative in the reconstruction. It adheres to the concept of replacing "like with like," as there are no muscles at the posterior midline. Methods: A retrospective study was performed of a cohort of 18 patients with deep SSI and a posterior midline defect after spinal surgery who received reconstruction with the MDICAP flap. A review of postoperative imaging with focus on dead space was performed. Results: All patients had satisfactory functional and aesthetic outcomes. No patients had a recurrent deep SSI during follow-up (average 64 mo, range 3-384 mo). In the 16 patients who had postoperative imaging performed, dead space was not present at the flaps' recipient site. Conclusions: The MDICAP flap is a good alternative to muscle flaps in reconstructive surgery for complex posterior midline defects caused by a deep SSI after spinal surgery. Postoperative imaging showed no dead space with the use of MDICAP flaps. All patients had an uneventful postoperative course with no recurrent infections. This challenges the dogmata of (1) the need for muscle flaps in such reconstruction and (2) the obligate need for dead space obliteration at the time of operation.