The iliohypogastric nerve (also iliopubic nerve, latin: nervus iliohypogastricus) is a mixed nerve that originates from the lumbar plexus and innervates the skin in the inguinal, pubical and gluteal region, and the abdominal muscles.
The iliohypogastric nerve originates from the ventral rami of the twelfth thoracic (T12) and first lumbar (L1) nerves.
The iliohypogastric nerve emerges from the lateral side of the psoas major, descends obliquely and above the iliac crest. Then the iliohypogastric nerve penetrates the transverse abdominal muscle, runs between it and the abdominal internal oblique muscle, and further between the abdominal internal oblique and external oblique muscles.
On its course the iliohypogastric nerve gives off two cutaneous branches, namely, the anterior and lateral cutaneous branches to innervate skin, and several motor branches to the abdominal muscles.
The anterior cutaneous branch of the iliohypogastric nerve pierces the aponeurosis of the abdominal external oblique muscle and innervates the skin in inguinal and pubical region.
The lateral cutaneous branch of the iliohypogastric nerve innervates the skin below the iliac crest and in the gluteal region.
The motor branches of the iliohypogastric nerve innervate the transverse abdominal muscle, the external and internal oblique muscles.