Anatomy Week 10 - Lumbar plexus Flashcards
(20 cards)
List the branches (peripheral nerves) of the Lumbar plexus.
- Iliohypogastric nerve
- Ilioinguinal nerve
- Genitofemoral nerve
- Lateral cutaneous of the thigh
- Obturator nerve
- Femoral nerve
Which spinal nerves form the lumbar plexus?
Anterior rami.
L1, L2, L3 and L4, with contributions from T12.
What spinal nerve roots does the Iliohypogastric nerve come from?
L1 with contributions from T12
What motor and sensory functions does the Iliohypogastric nerve innervate?
Motor fuctions: Innervates the internal oblique and transversus abdominis.
Sensory functions: Innervates the posterolateral gluteal skin and suprapubic region.
What spinal nerve root does the Ilioinguinal nerve come from?
L1
What motor and sensory functions does the Ilioinguinal nerve innervate?
Motor functions: Innervates the internal oblique and transversus abdominus.
Sensory functions: Innervates the skin on the genitalia and middle thigh.
What spinal nerve roots does the Genitofemoral nerve come from?
L1 and L2
What motor and sensory functions does the Genitofemoral nerve innervate?
Motor functions: The genital branch innervates the cremasteric muscle.
Sensory functions:
- The genital branch innervates the skin of the anterior scrotum in males and the external skin of the female genital area.
- The femoral branch innervates the skin on the upper anterior thigh.
What spinal nerve roots does the Lateral Cutaneous Nerve of the thigh come from?
L2 and L3
What motor and sensory functions does the Lateral Cutaneous Nerve of the thigh innervate?
Motor functions: None
Sensory Functions: Innervates the anterior lateral thigh down to the level of the knee.
What spinal nerve roots does the Obturator nerve come from?
L2, L3 and L4
What motor and sensory functions does the Obturator nerve innervate?
Motor functions: Innervates the muscles of the medial thigh.
Sensory nerve: Innervates the skin over the medial thigh.
What spinal nerve roots does the Femoral nerve come from?
L2, L3 and L4
What motor and sensory functions does the Femoral nerve innervate?
Motor: Innervates muscles of the anterior thigh.
- Hip flexors: Pectineus, iliacus, sartorius.
- Knee extensors: Quadriceps femoris.
Sensory: Innervates the skin on the anterior thigh and the medial leg.
- Saphenous nerve – a continuation of the posterior division of the femoral nerve. It supplies the skin of the medial leg and foot.
What is the anatomical course of the Iliohypogastric nerve?
Runs to the iliac crest, across the quadratus lumborum muscle of the posterior abdominal wall. Then perforates the transversus abdominis and divides into its terminal branches.
What is the anatomical course of the ilioinguinal nerve?
Follows the same anatomical course as the larger iliohypogastric nerve.
After innervating the muscles of the anterior abdominal wall, it passes through the superficial inguinal ring to innervate the skin of the genitalia and middle thigh.
What is the anatomical course of the genitofemoral nerve?
After leaving the psoas major muscle, the genitofemoral nerve quickly divides into a genital branch, and a femoral branch.
What is the anatomical course of the Lateral cutaneous nerve of thigh?
It enters the thigh at the lateral aspect of the inguinal ligament,
where it provides cutaneous innervation to the skin there.
What is the anatomical course of the obturator nerve?
Enters the medial thigh via the obturator
canal.
Divides into 2 branches:
* Anterior (anterior to the adductor brevis) branch
* Posterior (posterior to the adductor brevis)
What is the anatomical course of the femoral nerve?
Passes underneath the inguinal ligament to enter the femoral triangle.
