Myelomeningocele defect reconstruction with keystone flaps: vascular rationale for the design and operative technique

Abstract

Background: Myelomeningocele is a frequently seen condition at tertiary care hospitals. Its treatment involves a variety of plastic reconstructive techniques. Herein, we present a series of myelomeningocele patients treated using keystone flaps.

Methods: We gathered information regarding soft tissue reconstruction and the use of bilateral keystone flaps to treat myelomeningocele patients. We obtained data from clinical records and recorded the demographic characteristics of mothers and children with the condition. The size, level of defect, and complications detected during the follow-up were analyzed.

Results: A series of seven patients who underwent bilateral keystone flaps for myelomeningocele closure was analyzed. There were no cases of midline or major dehiscence, flap loss, necrosis, surgical site infections, or cerebrospinal fluid leakage. No revision procedures were performed. Minor complications included one case with minimal seroma and three cases with areas of peripheral dehiscence that healed easily using conventional measures.

Conclusions: The use of keystone flaps is an adequate option for closure of dorsal midline soft tissue defects related to myelomeningocele. This technique offers predictable results with an acceptable spectrum of complications. Robust blood flow can be predicted based upon anatomical knowledge.

Keywords: Meningomyelocele; Spinal dysraphism; Surgery, plastic; Surgical flaps.

Conflict of interest statement

Conflict of interest

No potential conflict of interest relevant to this article was reported.

Figures

Fig. 1.

Multi-perforator advancement flap. The keystone flap design safely includes thoracic and lumbar perforators along a longitudinal axis. Potential involvement of perforators depending on the level of the defect. Color code: purple, parascapular and scapular branches of the circumflex scapular artery superiorly, and dorsal intercostal arteries medially and inferiorly; yellow, intercostal arteries; blue, intercostal arteries, extensions of the superficial circumflex iliac artery laterally, and lumbar arteries inferiorly and medially; green, lumbar arteries.

Fig. 2.

Conventional double opposing keystone flap. (A) Patient with a skin defect after neural tube and meningeal closure (81 cm2). The surrounding skin was thin, macerated, and friable. For the keystone flap design, the defect diameter was marked in a 1:1 proportion bilaterally. Lines extended at right angles from the corners of the ellipse. When joining the opposite end, the flap was shaped on each side according to the width of the defect. (B) Blunt dissection enabled the preservation of perforators beneath the flap surface. A midline closure was done, at first covering the defect. Secondary defects at the edges were closed in a V-Y fashion, which relaxed the horizontal tension. Drains were placed and bolsters can be used to prevent the sutures from cutting through the skin. (D, E) Follow-up at postoperative days 7 and 21, respectively: no necrosis or wound dehiscence was noted. (C, F) Diagrams of the design and result of bilateral keystone flaps (modified from Gaskill. Neurosurg Focus 2004;16:E3 [25]).

Fig. 3.

Double keystone flap with an omega design. (A) Patient with a thoracolumbar myelomeningocele defect (79 cm2). (B) Immediate postoperative result shows a fish-mouth modification of the left keystone flap. Moderate bulging after inset may be present. (D) On postoperative day 5, a congestive color change was observed that resolved within a few days without any additional measures. Notice flattening of the fishmouth configuration and proper wound healing. (E) Follow-up at 10 months of age. (C, F) Diagrams for the design and result of bilateral keystone flaps with an omega (Ω) or fish-mouth modification (modified from Gaskill. Neurosurg Focus 2004;16:E3 [25]).