Lower limb
Iliohypogastric nerve
Nervus iliohypogastricus
- Origin
- Superior branch of the lumbar plexus arising from anterior ramus L1 (often with T12 contribution)
- Insertion
- Crosses quadratus lumborum, pierces transversus abdominis, and divides above the iliac crest into a lateral cutaneous branch (buttock) and anterior cutaneous branch (suprapubic)
- Function
- Motor to internal oblique and transversus abdominis muscles; sensory to the posterolateral gluteal skin and the suprapubic/hypogastric region
- Innervation
- Mixed nerve innervating lower abdominal wall and suprapubic skin
- Movement & chain
- Assists core abdominal wall bracing and intra-abdominal pressure generation
- Palpation
- Sensory testing over the hypogastric region ~2-3 cm superior to the pubic symphysis
- Clinical
- Iatrogenic entrapment or transection during appendectomy (McBurney incision), inguinal herniorrhaphy, or Pfannenstiel incision for cesarean delivery causing burning suprapubic pain
- Segmental innervation
- T12, L1 spinal segments
- In clinical practice
- Protected during low transverse abdominal incisions; targeted by ultrasound-guided iliohypogastric nerve block for postoperative groin/cesarean analgesia
- Region in the model
- Lower limb