Muscles of the Abdomen and Related Structures

Muscles of the axial skeleton

compression of abdomen; flexion and rotation of trunk/vertebral column

Rectus abdominis

centrally located muscle of abdomen

Location of rectus abdominis

xiphoid process and cartilage of ribs

Superior attachment of rectus abdominis

pubic symphysis and crest

Inferior attachment of rectus abdominis

compression of abdomen; alone: rotation of trunk/vertebral column. together: flexion of trunk/vertebral column

External oblique

superficial lateral muscle w/ fibers running medially on an angle

Location of external oblique

ribs

Superior attachment of external oblique

linea alba and iliac crest

Inferior attachment of external oblique

compression of abdomen; alone: rotation of trunk/vertebral column. together: flexion of trunk/vertebral column

Internal oblique

deep to external oblique; fibers run in opposite orientation

Location of internal oblique

iliac crest, inguinal ligament

Superior attachment of internal oblique

linea alba, iliac crest, ribs

Inferior attachment of internal oblique

compression of the abdomen

Transversus abdominis

deep to internal oblique; fibers run in a transverse plane

Location of transversus abdominis

iliac crest, inguinal ligament, cartilages of ribs

Superior attachment of transversus abdominis

linea alba and pubic crest

Inferior attachment of transversus abdominis

connective tissue sheath surrounding the rectus abdominis; formed from aponeuroses of external and internal oblique and transversus abdominis muscles

Rectus Sheath

tendinous structures that serves as insertion point for external and internal oblique and transversus abdominis muscles

Linea alba