The branches of the lumbar plexus may therefore be arranged as follows:
Iliohypogastric
1 L.
Ilioinguinal
1 L.
Genitofemoral
1, 2 L.
Dorsal divisions.
Lateral femoral cutaneous
2, 3 L.
Femoral
2, 3, 4 L.
Ventral divisions.
Obturator
2, 3, 4 L.
Accessory obturator
3, 4 L.
The Iliohypogastric Nerve (n. iliohypogastricus) arises from the first lumbar nerve. It emerges from the upper part of the lateral border of the Psoas major, and crosses obliquely in front of the Quadratus lumborum to the iliac crest. It then perforates the posterior part of the Transversus abdominis, near the crest of the ilium, and