Anatomy - lower limb - lumbar plexus

Question 1

where is lumbar plexus located

Answer 1

psoas major mm, ant transverse processes of lumbar vertebrae
descend post abdo wall

Question 2

plexus formed by

Answer 2

ant rami of L1-4 and T12

Question 3

iliohypogastric nerve
- root
- motor function
- sensation

Answer 3

root L1 (T12)
motor - innervates int oblique and transversus abdominis
sense - posterolateral gluteal skin in the pubic region

Question 4

ilioinguinal nerve
- root
- motor
- sensory

Answer 4

root L1
motor - internal oblique, transversus abdominis
sense - superior ant-medial thigh
+ root of penis and ant scrotum
+ mons pubis and labia major

Question 5

genitofemoral
root
motor
sensory

Answer 5

root L1-2
motor - genital branch innervates the cremasteric mm
sensation - genital branch innervates the skin to ant scorum and mons pubis/ labia majora
femoral branch - upp ant thigh

Question 6

lat cutaneous nerve thigh
root
motor
sense

Answer 6

root l2-3
motor none
sens ant-lat thigh down to the level of the knee

Question 7

obutator nerve
root
motor
sense

Answer 7

root l2-4
motor - medial thigh mm - obt externus, adductor longus, add brevis, add magnus and gracillis
sense - medial thigh

Question 8

femoral nerve
root
motor
sense

Answer 8

root l2-4
motor ant thigh - iliacus, pectineus, satorius, quadriceps femoris
sense - innerve ant thigh and medial leg