Myocutaneous sartorius flap for major congenital abdominal wall defects

Abstract

Management of giant omphalocele/gastroschisis remains unsatisfactory: primary fascial closure is not always possible, prosthetic applications lead to problems of infection and separation, and escharification or skin closure results in ventral hernias. We have therefore investigated the possible use of myocutaneous flaps in such situations. The myocutaneous flap, comprising a skin pedicle isolated along with the underlying muscle, has two major attractions: (1) the good blood supply minimises risks of infection and flap separation; and (2) the muscle pedicle provides a strong fascial-muscular closure. The flap has to fulfill four criteria: (1) it is viable; (2) it provides adequate coverage; (3) it reaches the defect; and (4) its transposition does not result in functional disability of the organ from which it originates. Based on an anatomical study of 20 post-mortem specimens in eight neonates and two adults, including contrast injections, we have found the sartorius musculocutaneous flap to be the ideal solution. The sartorius muscle is relatively more bulky in neonates than in adults. The major blood supply, which enters between its upper third and lower two thirds, can maintain a 7 × 3-cm flap. With the hips immobilised in flexion, the flap can reach the xiphisternum without tension. Our study suggests that it is feasible to repair neonatal abdominal wall defects of up to 7 × 6 cm by sartorius musculocutaneous flaps. In particular, this approach appears ideally suited for reconstruction in cloacal exstrophy and for secondary repair of ventral hernias resulting from escharification, skin closure alone, or failed prosthetic applications in giant omphalocele/gastroschisis.