rectusrecti

Rectus recti is an uncommon term sometimes used to refer to the rectus abdominis muscles. The standard anatomical name is rectus abdominis; the paired muscles run vertically along the anterior abdominal wall on either side of the midline and are separated by the linea alba.

Each rectus abdominis muscle originates from the pubic crest and pubic symphysis and inserts onto the xiphoid process and the costal cartilages of ribs 5 through 7. The muscle is divided into segments by tendinous intersections and is enclosed within the rectus sheath; its upper and lower portions can differ in thickness.

Innervation is via the thoracoabdominal nerves (anterior rami of T7–T11) and the subcostal nerve (T12); the lower part may receive additional innervation from the iliohypogastric and ilioinguinal nerves (L1). Blood supply comes from the superior and inferior epigastric arteries.

Functions of the rectus abdominis include flexion of the trunk, stabilization of the pelvis and spine, and increasing intra-abdominal pressure during forced expiration, coughing, defecation, and lifting. The muscles also contribute to posture and to movements such as bending forward or returning to an upright position.

Clinical notes: diastasis recti, a widening of the linea alba, can occur during pregnancy and postpartum, potentially affecting abdominal wall function. Rectus abdominis injuries are common in athletes and may involve strain of the muscle or weakness of the abdominal wall. Surgical approaches frequently involve the rectus sheath, particularly in midline (laparotomic) or reinforced incisions.