Upgrade to remove ads
Outline 8: Lumbosacral Plexus
Terms in this set (47)
What does the lumbar plexus primarily innervate?
1. Posterior abdominal wall muscles.
2. Anterior thigh muscles.
3. Medial thigh muscles.
Name the nerves of the lumbar plexus in order of how they emerge (superiorly to inferiorly).
4. lateral femoral cutaneous
5. femoral nerve
6. obturator nerve.
What branch(es) emerge from the anterior border of the psoas major?
The genitofemoral nerve.
What branch(es) emerge from the lateral border of the psoas major?
lateral femoral cutaneous
What branch(es) emerge from the medial border?
The obturator nerve.
Nerve roots of the iliohypogastric?
What does the iliohypogastric nerve innervate? (2 cutaneous, 1 muscle)
cutaneous to gluteal & lower abdomen
motor to lower abdominals
Nerve roots of the ilioinguinal?
What does the ilioinguinal nerve innervate? (1 cutaneous, 1 muscle)
Cutaneous to inguinal region (proximal medial thigh), motor to lower abdominals.
What does the genitofemoral nerve innervate? (2 cutaneous, 1 muscle)
Cutaneous to genital region (genital branch) and proximal anterior thigh (femoral branch).
Innervates the cremaster muscle (genital branch).
Nerve roots of the genitofemoral nerve?
Nerve roots of the lateral femoral cutaneous nerve?
What does the lateral femoral cutaneous nerve innervate? (1 cutaneous)
Cutaneous to proximal anterolateral thigh as far as the knee.
Nerve roots of the femoral nerve?
What muscles does the femoral nerve innervate? (8)
anterior thigh compartment muscles (rectus femoris, sartorius, vastus lateralis, vastus intermedius, vastus medialis),
What cutaneous branches does the femoral nerve divide into and what do they innervate?
Anterior femoral cutaneous nerve: skin of anterior side of thigh.
Saphenous nerve: Skin of medial side of leg.
What is so special about the saphenous nerve?
It is the only nerve of the lumbar plexus that innervates something below the knee.
Nerve roots of the obturator nerve?
What does the obturator nerve innervate? (muscles, 1 cutaneous, 1 articular)
Adductor muscles (medial thigh),
skin on medial mid-thigh,
articular branches to the hip joint.
What nerve roots does the lumbosacral trunk originate from?
What vertebrae contribute to the sacral plexus?
What does the sacral plexus primarily innervate? (3 general)
1. Posterior compartment thigh muscles.
3. All of the leg & foot below knee except the medial cutaneous leg.
Where does the sacral plexus form?
On the anterior surface of the piriformis muscle.
Where do the branches of the sacral plexus travel? (Except?)
All branches travel inferiorly to the piriformis except the superior gluteal nerve.
What muscles does the superior gluteal nerve innervate? (3)
Gluteus medius and minimus, TFL.
What muscles does the inferior gluteal nerve innervate? (1)
The gluteus maximus.
What muscles does the nerve to obterator internus innervate? (2)
Obterator internus and superior gemellus.
What does the nerve to quadratus femoris innervate? (2)
Quadratus femoris and the inferior gemellus.
What muscles do the branches to the piriformis innervate? (1)
What is unique about the posterior femoral cutaneous nerve?
It innervates more skin than any other cutaneous nerve.
What does the pudendal nerve innervate?
Provides sensory to external genitalia.
Perineum - skin and muscles.
Nerve roots of the sciatic nerve?
What is unique about the sciatic nerve?
It is made up of two separate nerves in a common sheath.
What are the two nerves inside the sheath and which one is more medial and which is more lateral?
The tibial nerve and common peroneal nerve.
The tibial nerve is more medial and the common proneal nerve is more lateral.
Where abouts does the sciatic nerve exit the pelvic region?
It exits halfway between the greater trochanter of the femur and the ischial tuberosity.
What does the sciatic nerve divide into?
Tibial nerve and common peroneal nerve.
What are the nerve roots of the tibial nerve?
What muscles does the tibial nerve innervate? (11)
biceps femoris (long head),
adductor magnus (posterior part),
flexor hallicus longus,
flexor digitorum longus,
What are the nerve roots of the common peroneal nerve?
What muscles does the common peroneal nerve innervate before dividing?
The short head of the biceps femoris.
What does the common peroneal nerve give off at the popliteal fossa?
The fibular communicating branch.
What does the tibial nerve give off at the popliteal fossa?
The medial sural cutaneous branch.
What structure do the fibular communicating branch and the medial sural cutaneous branch form?
The sural nerve.
What does the tibial nerve divide into after the popliteal fossa?
The medial and lateral plantar nerves.
What does the common peroneal nerve divide into?
It divides into the superficial peroneal nerve and the deep peroneal nerve.
What does the superficial nerve innervate? (2 muscles and 2 cutaneous)
Lateral compartment leg muscles - peroneus longus and peroneus brevis.
Lower anterolateral leg and dorsum of the foot.
What does the deep peroneal innervate? (which compartment and 2 foot muscles and 1 cutaneous area)
The anterior leg compartment and extensor digitorum brevis and extensor hallucis brevis.
Cutaneous: innervates the wedge between toes 1 and 2.
THIS SET IS OFTEN IN FOLDERS WITH...
anatomy of leg
Anatomy Test 3 Lecture 1 - Abdomen
GU, reproductive, breast
YOU MIGHT ALSO LIKE...
Lumbosacral Plexus (Outline #13)
Innervation of the Lower Extremity
BP 1 Spinal Anatomy - Spinal Nerve Plexuses
MUSCLE INNERVATIONS 2
OTHER SETS BY THIS CREATOR
USMLE Step 2 Cardiology
step 2 medicine 5
step 2 medicine 4
OTHER QUIZLET SETS
Psychology Chapter 1
Age of Exploration