腹直筋前鞘弁法による臍形成術は瘢痕を臍周囲に残さず深く縦長の臍窩を形成できる

An Umbilicoplasty Using the Rectus Abdominis Anterior Sheath Flap Technique can Create a Deep, Longitudinal Umbilical Fossa Without Leaving a Scar Around the Umbilicus

はじめに

　臍ヘルニア患者では臍周囲を腹直筋が迂回して走行しているために，傍臍部の腹壁の厚みが薄く，臍窩の横幅も広い。このため，縫着法 1）～4）や皮弁法 5）～12）の手術を行っても，傍臍部の腹壁の厚みが薄いために，臍窩の深みは形成しにくく，臍の形態も横広がりのままとなりやすい。腹直筋前鞘弁法は，片側の腹直筋前鞘に短冊形の弁を形成し，対側の腹直筋前鞘を通して元の位置に縫合し，左右に離開した腹直筋の位置を整位する手術手技である 13）。腹直筋の整位により，傍臍部の腹壁の厚みが増加することで，自然と臍の深みが形成されると同時に，腹直筋が正中側に引き寄せられることで，幅が狭く，縦長で深い，いわゆる良い形態の臍形成が可能である（図1） 14）。本術式を中心としたわれわれの臍ヘルニア治療の詳細について述べる。

　We describe the application of a rectus abdominis anterior sheath flap in a surgical procedure that creates a deep and natural umbilicus by providing an anatomical realignment of the rectus abdominis muscle. In patients with an umbilical hernia, the rectus abdominis muscle wraps around the umbilicus, resulting in a thin abdominal wall in the paraumbilical region and a wide umbilical fossa. Therefore, even if a conventional umbilicoplasty is performed, it is difficult to form a sufficiently deep umbilical fossa due to the thinness of the abdominal wall in the paraumbilical region, and the umbilical configuration tends to remain horizontally expanded. The rectus abdominis anterior sheath flap technique is a surgical procedure in which a strip-shaped flap is formed in the rectus abdominis anterior sheath on one side and sutured through the contralateral rectus abdominis anterior sheath to its original position in order to realign the left and right separated rectus muscles. Realignment of the rectus abdominis muscle increases the thickness of the abdominal wall in the paraumbilical region, which naturally forms the depth of the umbilicus and at the same time pulls the rectus abdominis muscle toward the midline, allowing for a narrower, so-called good shape of the umbilicus.