Lecture 17, Lumbosacral Plexus

Question 1

Lumbosacral Plexus

Answer 1

nerves to hip muscles and lower limb (5 components to it)
(in the posterior part of the psoas major, anterior to the lumbar transverse processes)
- this nerve network is composed of the anterior rami of L1 & L4 nerves

Question 2

Obturator nerve (L2-L4)

Answer 2

emerges from the medial border of the psoas major and passes through the pelvis to the medial thigh, supplying the adductor muscles

Question 3

Femoral nerve (L2-L4)

Answer 3

emerges from the lateral border of the psoas major and innervates the iliacus and passes deep to the inguinal ligament to the anterior thigh, supplying the flexors of the hip and extensors of the knee

Question 4

Lumbosacral trunk (L4,L5)

Answer 4

passes over the ala (wing) of the sacrum and descends into the pelvis to participate in the formation of the sacral plexus along with the anterior rami of the S1-S4 nerves

Question 5

Sciatic nerve

Answer 5

a major nerve extending from the lower end of the spinal cord down the back of the thigh, and dividing above the knee joint. It is the nerve with the largest diameter in the human body