MuscleAbdominal wall — deepest
Transversus abdominis
Latin: M. transversus abdominis
Location: Abdomen
View the transversus abdominis in 3DOrigin
Inner surfaces of ribs 7–12, thoracolumbar fascia, iliac crest and inguinal ligament.
Insertion
Linea alba via the aponeurosis, fusing with the internal oblique's lower fibres.
Action
The body's natural corset: compresses the abdomen, raises intra-abdominal pressure for coughing, defecation and childbirth, and stiffens the trunk in anticipation of limb movement.
Nerve supply
T7–T12, L1 (iliohypogastric, ilioinguinal).
Blood supply
Deep circumflex iliac and lumbar arteries.
Clinical relevance
TAP (transversus abdominis plane) blocks anaesthetise the nerves between it and the internal oblique — the analgesic backbone of modern abdominal surgery.
Educational anatomy reference, not medical advice. About this content.