Abdominal and respiratory muscles:

External abdominal oblique

Supports abdominal viscera against gravity, stabilizes the vertebral column, rotates the torso contralaterally, flexes the vertebral column forward, and compresses the abdominal cavity.

Aponeurosis of external oblique

A broad, flat tendon composed of dense collagen fibers that extends across the abdomen from the external oblique muscle.

Linea alba

A fibrous band of connective tissue running vertically down the center of the abdominal wall.

Internal abdominal oblique

A thin muscle of the lateral abdominal wall, involved in trunk flexion, increasing abdominal pressure, and stability during movement.

Rectus sheath

A strong fibrous compartment enclosing the rectus abdominis and pyramidalis muscles.

Inguinal ligament

Connects abdominal oblique muscles to the pelvis and protects tissues, lymphatics, nerves, and blood vessels between the abdomen and legs.

Transverse abdominal

The deepest layer of abdominal muscles acting as a stabilizer for the lumbar spine and lumbopelvic region.

Tendinous intersections of rectus

Fibrous bands that cross the Rectus Abdominis muscle, typically three or four in number.

Rectus abdominis

A vertical muscle at the front of the abdomen that flexes the waist.

Diaphragm

A muscular dome between the thoracic and abdominal cavities, serving as the prime mover of inspiration.

External Intercostals

11 pairs of superficial muscles located between the first 12 ribs.

Internal Intercostals

Muscles located deeper to the external intercostals.