TBL 14: functional anatomy of Lumbar plexus

Question 1

Femoral nerve– arises from

Answer 1

posterior divisions of L2 to L4 spinal segments

Question 1

Blood supply to the Lumbosacral plexus is derived from:

Answer 1

i) Lumbar branch of Iliolumbar artery (branch of Internal iliac artery)

Question 2

muscles innervated by Femoral nerve-

Answer 2

Question 3

Femoral nerve gives rise to what cutaneous branches?

Answer 3

II. Anterior cutaneous nerve of thigh– sensory branch to skin at anterior surface of thigh

III. Saphenous nerve to the skin of– medial surface of knee, and anteromedial surface of
leg as far as foot

medial leg

fame gives rise to sad ant

Question 4

• Injury to Femoral nerve can result in:

Answer 4

• weakened/difficultyflexionofthighathipjoint
• weakened/difficultyextensionofknee
• lossofsomaticskinsensations(e.g,touch,etc)onanteriorsurfaceofthigh,medialsurfaceknee, and anteromedial surface of leg as far as foot

Question 5

Lateral femoral cutaneous nerve of thigh:
– arises from ________

– gives off following branches:

Answer 5

posterior divisions of L2, and L3 spinal segments

I. Anterior branch to skin at– anterolateral area of thigh as far as knee

II. Posterior branch to skin– over the greater trochanter of femur

Question 6

Obturator nerve– arises from

what muscles does it innervate?

Answer 6

anterior divisions of L2 to L4 spinal segments

I. Motor (muscular) branches to– 1. Obturator externus– lateral (external) rotation of thigh at hip joint, abduction of hip, and stabilizes hip joint

2. Muscles of medial compartment of thigh [Gracilis, Adductor longus, Adductor brevis, and pubofemoral (adductor) portion of Adductor magnus– adduction and medial (internal) rotation of thigh]

II. Sensory branches to the skin at– medial (inner) aspect of thigh

III. Articular branches to– Hip and Knee joints

Question 7

obturator, cutaneous innervation

Answer 7

Question 8

obturator nerve innervates:

direct branch
anterior branch
posterior branch

Answer 8

Question 9

Injury to Obturator nerve can result in:

Answer 9

• weakened adduction and medial rotation of knee
• loss of somatic sensations (e.g, touch, etc) on medial aspect of thigh

Question 10

Iliohypogastric nerve– arises from _______ segment – gives off following branches:
I. Motor (muscular) branches to– ________

II. Sensory branches to the skin at–

Answer 10

Iliohypogastric nerve– arises from L1 spinal segment – gives off following branches:

I. Motor (muscular) branches to– Internal oblique, Transversus abdominis, and Quadratus lumborum

II. Sensory branches to the skin at– inferior part of abdomen, lateral aspect of hip, supra pubic region, skin over the greater trochanter of femur

Question 11

Ilioinguinal nerve– arises from_____spinal segments
– gives off following branches:

motor brach to:

sensory branch:

Answer 11

I. Some motor (muscular) branches to– Internal oblique, and Transversus abdominis (like illiohypogastric) (contraction of
both these muscles result in compression of abdominal cavity)

II. Sensory branches to the skin at– superomedial aspect of thigh, around pubic symphysis, root of penis, superolateral aspect of scrotum (males)/ or labia
majora (females)

tile color

Question 12

anterior

Answer 12

Question 13

posterior

Answer 13

Question 14

Genitofemoral nerve– arises from_______ spinal segment

femoral branch

Genital branch–

Answer 14

Genitofemoral nerve– arises from L1, and L2 spinal segment

I. Genital branch–

– provides motor (muscular) input to Cremaster muscle (contraction of cremaster
muscle raises the scrotum)
– provides primary sensory supply to skin in– pubic region, scrotum (males)/ or labia majora (females)

II. Femoral branch– provides sensory supply to the skin at– superoanterior and medial aspect of thigh (superolateral part of femoral
triangle)

Question 15

Cremasteric reflex, and its physiological and clinical significance:

Answer 15

Question 16

Lumbar disc herniation (L4-L5) can:

Answer 16

a) result in occlusion of the intervertebral foramen, which can mechanically compress lumbar
spinal nerves

Question 17

Branches of Lumbar plexus can be accidentally injured during following surgical procedures:

Answer 17

a) Hip surgery– damaging branches of Femoral or Obturator
b) Anterior abdominal approach surgery– resulting in injury to the branches of Iliohypogastric, Ilioinguinal or Genitofemoral nerves
c) Lateral retroperitoneal transpsoas approach surgery– causing damage to branches of Lumbosacral plexus

Question 18

Nerve blocks to Iliohypogastric, Ilioinguinal or Genitofemoral nerves are clinically used for the management of:

Answer 18

a) Patients undergoing an elective cesarian section for delivery of the baby

b) Children requiring inguinal hernia surgery

Question 19

Injury to Lumbosacral plexus and its branches symptoms

Answer 19

Question 20

Sacral plexus:

arises at the level of ____vertebrae

Answer 20

L4-S4

provides motor and sensory nerves for part of the pelvis, posterior thigh, lower leg and foot

Question 21

what are the major branches of the Sacral plexus:

Answer 21

Question 22

Gluteus medius, Gluteus minimus, and Tensor fascia latae muscles are innervated by ________, and Gluteus maximus is innervated by _________

Answer 22

Gluteus medius, Gluteus minimus, and Tensor fascia latae muscles are innervated by Superior gluteal nerve, and Gluteus maximus is innervated by Inferior gluteal nerve

Question 23

where does the gluteus max originate and attach?

Answer 23

Question 24

Question 25

Superior gluteal nerve (________)-- innervates actions of muscles innervated

Answer 25

Superior gluteal nerve (L4, L5, and S1) provides innervation to the Gluteus medius, Gluteus minimus, and Tensor fasciae latae muscles (which abduct and medially (internally) rotate the extended thigh at the hip joint, and stabilize the femur head in the hip joint)

Question 26

Clinical significance of Superior gluteal nerve:

Answer 26

Question 27

Inferior gluteal nerve innervations clinical significance

Answer 27

Question 28

sciatic nerve L4-S3 * At the level of thigh, Sciatic nerve innervates the: common fibular vs tibial branch

Answer 28

I. Hamstring muscles at the posterior compartment of thigh (Semitendinosus, Semimembranosus, and long of Biceps femoris (by tibial branch), short head of bicep femoris by common fibular branch. Help in extension of thigh at hip joint, flexion of leg at the knee joint, and assist in internal [medial] rotation of flexed knee) II. Ischiocondylar (hamstring) portion of Adductor magnus-- which is an adductor of thigh, and aids in extension at hip joint----by tibial branch

Question 29

Tibial nerve of sciatica -- which provide sensory innervation to skin at the________, innervates the muscles in the __________ sensory branches

Answer 29

which provide sensory innervation to skin at the sole of foot(sural, calcaneal, plantar branches) , innervates the muscles in the posterior compartment of the leg and sole of the foot allows for plantar flexion

Question 30

Tibial nerve of sciatica Motor branches to muscles in posterior compartment of leg-- _______________muscles____________________________--- plantar flex foot, flex digits

Answer 30

Tibial nerve of sciatica Motor branches to muscles in posterior compartment of leg-- gastrocnemius, soleus, plantaris, popliteus, tibialis posterior, flexor digitorum longus, and flexor hallucis longus muscles--- plantar flex foot, flex digits

Question 31

Tibial nerve of sciatica Medial plantar nerve which provide motor innervation to

Answer 31

Medial plantar nerve which provide motor innervation to-- abductor hallucis, flexor digitorum brevis, flexor hallucis brevis and the first lumbrical, and sensory innervation to medial aspect of sole and medial three- and one-half toes

Question 32

Tibial nerve of sciatica Lateral plantar nerve which innervates-

Answer 32

. Lateral plantar nerve which innervates-- flexor digitorum accessorius and abductor digiti minimi, flexor digiti minimi brevis

Question 33

Tibial nerve of sciatica _____________ nerve which supplies the skin of the lower half of the back of the leg and lateral border of the foot until the tip of the little toe

Answer 33

v. Sural cutaneous nerve which supplies the skin of the lower half of the back of the leg and lateral border of the foot until the tip of the little toe

Question 34

Tibial nerve of sciatica ______nerve which supply the skin of the posteroinferior back surface of heel

Answer 34

vi. Medial calcaneal nerve which supply the skin of the posteroinferior back surface of heel

Question 35

Clinical significance of Tibial nerve:

Answer 35

Clinical significance of Tibial nerve: Injury to the Tibial nerve in the knee or leg or foot regions can result in: -- weakness/paralysis of muscles in the posterior compartment of the leg and sole of the foot -- weakened plantar flexion, weakened foot inversion, and weakened flexion of digits -- loss of skin sensory sensations on leg, and at the sole of foot

Question 36

sciatic: Common fibular (peroneal/external popliteal/lateral popliteal) nerve-- which innervates and gives off which branches

Answer 36

Question 37

Nerve to the short head of Biceps femoris muscle of thigh-- which helps in knee flexion comes from???

Answer 37

common fibular nerve of sciatic nerve

Question 38

what muscles are innervated by the sciatic common fibular nerve? what action is down by this nerve

Answer 38

Superficial fibular (peroneal) nerve-- innervates the muscles of the lateral compartment of leg (Fibularis longus, and Fibularis brevis-- helps in eversion and plantar flexion of foot), also provides sensory innervation to skin over the antero-lateral surface of the leg along with the greater part of the dorsum of foot

Question 39

sciatic Deep fibular (peroneal) nerve-- innervate the muscles of what action is done

Answer 39

Deep fibular (peroneal) nerve-- innervate the muscles of the anterior compartment of leg (Tibialis anterior, Extensor hallucis longus, Extensor digitorum longus, Fibularis tertius-- helps in inversion and dorsiflexion of foot, and extension of digits)

Question 40

Clinical significance of Common fibular nerve and its branches:

Answer 40

Question 41

Piriformis Syndrome

Answer 41

Question 42

Clinical significance of Sciatic nerve and its branches:

Answer 42

Question 43

label

Answer 43