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Flashcards in The Lumbosacral Plexus Deck (22)
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1

Remember that the aorta divides into the right & left common iliac arteries at ~ _____ vertebral column level

L4

2

The common iliacs then descend along the pelvic brim and bifurcate into the ____ and ___

external & internal iliac arteries

3

Each external iliac arteries eventually passes beneath the inguinal ligament and becomes the ____

femoral artery 

4

Each internal iliac artery then descends into the pelvic cavity along the lateral wall and branches into two main divisions:

1.Anterior division

2.Posterior division

5

The anterior division of the internal iliac artery gives rise to branches that supply the 

pelvic viscera (we will study these visceral branches in the Repro Block next fall), structures in the perineum (i.e., external genitalia), and the gluteal region

6

While the posterior division of the internal iliac contributes branches that supply the _____, ____, ____ and ____

gluteal muscles/region, the lower back, and nearby sacral nerves and surrounding meninges (i.e. cauda equina)

7

The posterior division of the internal iliac generally gives rise to three branches:

 

1.Iliolumbar

2.Lateral sacral

3.Superior gluteal

8

The Lumbosacral plexus is formed by a collection of ventral/dorsal rami of the lumbar and sacral spinal nerves

ventral 

9

Lumbar Plexus- is formed by the ventral rami of spinal nerves ____ and the associated nerves which arise from these ventral rami

L1- L4

10

____ formed by the ventral rami of L2 & L3- (courses beneath the inguinal ligament) supplies sensation to anterolateral thigh

Lateral Femoral Cutaneous Nerve

11

_____  formed by ventral rami of L1 & L2 and gives rise to two branches:

1.Genital Branch- traverses the inguinal canal and innervates the scrotum/labia majora

2.Femoral Branch- supplies sensation to a small area on the proximal/anterior thigh                                 

Genitofemoral nerve

12

Two major nerves arise from the ventral rami of L2, L3 & L4:

1.Femoral Nerve- passes beneath the inguinal ligament and innervates the anterior thigh muscles (i.e. quadriceps and others)

 

2.Obturator Nerve- passes through the “obturator canal” and innervates the medial thigh muscles (adductors)

 

13

Sacral Plexus- is formed by the ventral rami of ____ and the associated nerves which arise from these ventral rami

L4, L5 & S1- S4

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