Lumbar Plexus Flashcards
(24 cards)
Roots of Lumbar Plexus
L1-L4 ventral rami (with occasional T12 contribution).
Major Branches of Lumbar Plexus
Iliohypogastric, Ilioinguinal, Genitofemoral, Lateral Femoral Cutaneous, Femoral, Obturator, Lumbosacral Trunk.
Iliohypogastric Nerve (Roots)
Arises from L1.
Iliohypogastric Nerve (Motor Innervation)
Internal oblique and transversus abdominis muscles.
Iliohypogastric Nerve (Sensory Innervation)
Skin over hypogastric region and iliac crest.
Ilioinguinal Nerve (Roots)
Arises from L1.
Ilioinguinal Nerve (Motor Innervation)
No significant motor function.
Ilioinguinal Nerve (Sensory Innervation)
Skin over medial thigh, scrotum/labia majora.
Genitofemoral Nerve (Roots)
Arises from L1-L2.
Genitofemoral Nerve (Branches)
Genital branch and femoral branch.
Genital Branch (Function)
Innervates cremaster muscle (motor) and skin of scrotum/labia (sensory).
Femoral Branch (Function)
Sensory to skin over femoral triangle.
Lateral Femoral Cutaneous Nerve (Roots)
Arises from L2-L3.
Lateral Femoral Cutaneous Nerve (Function)
Sensory to lateral thigh.
Femoral Nerve (Roots)
Arises from L2-L4.
Femoral Nerve (Motor Innervation)
Iliacus, psoas major, quadriceps femoris (rectus femoris, vastus lateralis, medialis, intermedius).
Femoral Nerve (Sensory Innervation)
Anterior thigh (via anterior cutaneous branches) and medial leg (via saphenous nerve).
Obturator Nerve (Roots)
Arises from L2-L4.
Obturator Nerve (Motor Innervation)
Adductor muscles (longus, brevis, magnus), gracilis, and obturator externus.
Obturator Nerve (Sensory Innervation)
Skin of medial thigh.
Lumbosacral Trunk (Roots)
Arises from L4-L5.
Lumbosacral Trunk (Function)
Connects lumbar plexus to sacral plexus; contributes to sciatic nerve.
Position of Lumbar Plexus
Within psoas major muscle (posterior to psoas fascia).
Mnemonics for Branches
‘IIGO FL’: Iliohypogastric, Ilioinguinal, Genitofemoral, Obturator, Femoral, Lateral femoral cutaneous.
