Derived from L1 root of the lumbar plexus. Emerges from the lateral aspect of the psoas muscle and travels along the posterior abdominal wall, travelling over quadratus lumborum and iliacus. It pierces the transversus abdominis and internal oblique near the anterior superior iliac spine to enter the inguinal canal.
It provides sensory innervation to the upper medial part of the thigh, the root of the penis and upper scrotum (in males) and mons pubis and labium majus (in females).
Ilioinguinal nerve block
Is can be blocked with local anaesthesia prior or during inguinal hernia surgery.