Lower limb
Ilioinguinal nerve
Nervus ilioinguinalis
- Origin
- Arises from the anterior ramus of the L1 spinal nerve from the lumbar plexus
- Insertion
- Travels along the iliac crest, enters the inguinal canal through the internal oblique, and emerges through the superficial inguinal ring into the groin and genitalia
- Function
- Motor to the lowest fibers of internal oblique and transversus abdominis; sensory to the upper medial thigh, base of penis/scrotum (anterior scrotal nerves) or mons pubis/labium majus
- Innervation
- Mixed nerve providing sensation to the groin crease and external genitalia
- Movement & chain
- Traverses the inguinal canal anterior to the spermatic cord
- Palpation
- Sensory testing over the root of the scrotum/labium and proximal medial thigh
- Clinical
- Chronic post-herniorrhaphy groin pain (inguinodynia from nerve entrapment, suturing, or mesh scarring following open hernia repair)
- Segmental innervation
- L1 spinal segment
- In clinical practice
- Mandatory identification and preservation (or intentional prophylactic neurectomy) during Lichtenstein hernia repair to avoid chronic neuropathic pain
- Region in the model
- Lower limb