aponeurosis of internal oblique muscle

Introduction

A broad flat tendinous portion of the internal oblique muscle. Its fibers run upward & medially, becoming continuous over the ribs with the internal intercostal muscles. The superior 2/3s split into 2 layers, or laminae at the lateral border of the rectus abdominis; one laminae passing anterior to the muscle & the other posterior to it.

The posterior lamina joins the aponeurosis of the transversus abdominis muscle to form the posterior layer of the rectus sheath. The tendons of these muscles pass medially in the form of broad aponeuroses that insert on a midline linea alba. The fascia of these muscles blend together at their lower margins to form the inguinal ligament.

More general terms

• aponeurosis

Additional terms

• aponeurosis of external oblique muscle
• conjoint tendon (inguinal falx)
• inguinal canal
• inguinal hernia