Nerves of the lower limb Flashcards
What spinal segments form the lumbar plexus?
T12-L4
What spinal segments form the sacral plexus?
L4–S4
Where is the lumbar plexus located?
Within the psoas major muscle.
Where is the sacral plexus located?
In the pelvis, anterior to the piriformis muscle.
What are the major branches of the lumbar plexus?
- Iliohypogastric
- ilioinguinal
- genitofemoral
- lateral femoral cutaneous
- femoral
- obturator nerves.
What are the major branches of the sacral plexus?
- Superior gluteal
- inferior gluteal
- sciatic
- posterior femoral cutaneous
- pudendal nerves.
What are the root values of the femoral nerve?
L2–L4
What does the femoral nerve innervate (motor)?
Anterior thigh muscles: iliacus, sartorius, quadriceps femoris, pectineus (partially).
What does the femoral nerve innervate (sensory)?
Anterior and medial thigh, medial leg and foot (via saphenous nerve).
What are the root values of the obturator nerve?
L2–L4
What does the obturator nerve innervate (motor)?
Medial thigh muscles: adductors, gracilis, obturator externus.
What does the obturator nerve innervate (sensory)?
Medial thigh skin.
What are the root values of the sciatic nerve?
L4–S3
What are the branches of the sciatic nerve?
Tibial nerve and common fibular (peroneal) nerve.
What muscles does the sciatic nerve innervate (before branching)?
Hamstrings and part of adductor magnus.
What are the root values of the tibial nerve?
L4–S3
What does the tibial nerve innervate (motor)?
Posterior compartment of leg and sole of foot.
What does the tibial nerve innervate (sensory)?
Sole of foot, via medial and lateral plantar nerves.
What are the root values of the common fibular nerve?
L4–S2
What are the branches of the common fibular nerve?
Superficial and deep fibular nerves.
What does the superficial fibular nerve innervate?
Lateral leg muscles; skin of dorsum of foot.
What does the deep fibular nerve innervate?
Anterior leg muscles; skin between first and second toes.
What are the root values of the superior gluteal nerve?
L4–S1
What muscles does the superior gluteal nerve supply?
Gluteus medius, gluteus minimus, tensor fasciae latae.
