Lumber and Lumbosacral
Plexuses
Lumber Plexus
Formed by ventral rami of L1-L5 spinal nerves, with 1 branch from T12 nerve
Superficial Nerve
Iliohypogastric Nerve
From L1 nerve
Ilioinguinal Nerve
From L1 nerve
Genitofemoral Nerve
From L1 + L2 nerve
Lateral Cutaneous Nerve of Thigh
From L2 + L3 nerve
Inferior Nerve
Obturator Nerve
L2 + L3 + L4 (ANTERIOR
BRANCHES)
Femoral Nerve
L2+L3+L4 (POSTERIOR
BRANCHES)
Lumbosacral Trunk
L4+L5
Iliohypogastric Nerve
Lumber and Lumbosacral Plexuses 1
, Iliohypogastric nerve penetrates the
abdominal wall muscles ⇒ course
towards the lateral hip region
Not that fully relevant to the lower
limb
Supply a cutaneous branch for
the skin of the hypogastric
region
Ilioinguinal Nerve
Course along the
iliohypogastric nerve
Innervates the skin
near the pubic area
Genitofemoral Nerve
Travel through the
inguinal ligament
Innervate the lateral
thigh
Lateral Femoral Cutaneous Nerve (Clinical Important)
Emerge from psoas
major
Lumber and Lumbosacral Plexuses 2
Plexuses
Lumber Plexus
Formed by ventral rami of L1-L5 spinal nerves, with 1 branch from T12 nerve
Superficial Nerve
Iliohypogastric Nerve
From L1 nerve
Ilioinguinal Nerve
From L1 nerve
Genitofemoral Nerve
From L1 + L2 nerve
Lateral Cutaneous Nerve of Thigh
From L2 + L3 nerve
Inferior Nerve
Obturator Nerve
L2 + L3 + L4 (ANTERIOR
BRANCHES)
Femoral Nerve
L2+L3+L4 (POSTERIOR
BRANCHES)
Lumbosacral Trunk
L4+L5
Iliohypogastric Nerve
Lumber and Lumbosacral Plexuses 1
, Iliohypogastric nerve penetrates the
abdominal wall muscles ⇒ course
towards the lateral hip region
Not that fully relevant to the lower
limb
Supply a cutaneous branch for
the skin of the hypogastric
region
Ilioinguinal Nerve
Course along the
iliohypogastric nerve
Innervates the skin
near the pubic area
Genitofemoral Nerve
Travel through the
inguinal ligament
Innervate the lateral
thigh
Lateral Femoral Cutaneous Nerve (Clinical Important)
Emerge from psoas
major
Lumber and Lumbosacral Plexuses 2
