Week 2 Msi: Review Of Lumbar And Sacral Nerves

Front 1

What makes up the lumbar plexus?

Back 1

ventral rami of L1-L4

Front 2

What makes up the lumbosacral plexus?

Back 2

ventral rami of L4-S4

Front 3

lumbar plexus lies deep to what muscle?

Back 3

psoas m

Front 4

lumbosacral plexus is located on the internal surface of what muscle?

Back 4

piriformis m

Front 5

What does lumbar plexus supply?

Back 5

anterior and medial thigh compartments

Front 6

What does the lumbosacral plexus supply?

Back 6

gluteal region, posterior thigh, entire leg and foot

Front 7

main nerves of lumbar plexus

Back 7

iliohypogastric, ilioginguinal, genitofemoral (L1,L2), lateral femoral cutaneous, femoral (L2-L4), obturator (L2-L4)

Front 8

Iliohypogastric N motor

Back 8

internal oblique, transversus abdominis

Front 9

Iliohypogastric N sensory:

Back 9

Anterior cutaneous:skin above pubis
Lateral cutaneous: skin of upper buttock

Front 10

exits lateral border of psoas and runs anterior to quadratus lumborum m until it pierces the transversus abdominis near iliac crest and then pierces internal oblique to continue medially bt internal and external oblique mm. It crosses onto the anterior abdominal wall just above/at the anterior superior iliac spine

Back 10

iliohypogastric

Front 11

upper portion of L1

Back 11

iliohypogastric

Front 12

lower portion of L1

Back 12

ilioinguinal N

Front 13

Ilioinguinal motor fxn

Back 13

internal oblique, transversus abdominis

Front 14

ilioinguinal sensory fxn

Back 14

cutaneous branches supply upper medial thigh and anterior scrotum/labia majora

Front 15

exits lateral border of psoas and runs anterior to quadratus lumborum. It then pierces transversus and internal oblique to run bt internal and external oblique aponeuroses. It follows the spermatic cord or round ligament of the uterus through the inguinal canal and exits through the superficial inguinal canal

Back 15

ilioinguinal N

Front 16

Nerve that is afferent and efferent limb of cremasteric reflex

Back 16

genitofemoral

Front 17

Has components of L1 and L2

Back 17

genitofemoral

Front 18

genitofemoral motor

Back 18

cremaster muscle in spermatic cord

Front 19

genitofemoral sensory

Back 19

Genital branch: scrotum/labia majora
Femoral branch: skin over femoral triangle and upper medial though

Front 20

boundaries of femoral triangel

Back 20

superior: inguinal ligament
Lateral: sartorious M
Medial: adductor longus M

Front 21

Comes through the psoas major and runs toward the inguinal ligament on the psoas major anterior surface. Near the inguinal ligament it divides with femoral branch entering femoral sheath and genital branch entering inguinal canal accompanying the spermatic cord

Back 21

genitofemoral

Front 22

derived from L2-L3

Back 22

Lateral femoral cutaneous N, sensory only

Front 23

Lateral femoral cutaneous sensory

Back 23

innervates skin of lateral thigh

Front 24

exits lateral border of psoas and runs anterior to iliacus to enter thigh posterior to inguinal ligament

Back 24

lateral femoral cutaneous N

Front 25

consists of L2-L4

Back 25

femoral and obturator N

Front 26

femoral N motor fxn

Back 26

mm of anterior compartment of thigh

Front 27

femoral N sensory

Back 27

skin over anterior thigh

Front 28

result of lesion of femoral N

Back 28

decrease in strength of hip flexion and knee extension

Front 29

exits lateral borer of psoas bt the psoas and iliacus to enter thigh deep to inguinal ligament, lateral and outside femoral sheath. It runs lateral to femoral vessels in the femoral triangle and then divides into many muscular branches and cutaneous branches. Terminates as saphenous nerve.

Back 29

femoral n

Front 30

provides sensory innervation for skin over medial leg and medial side of the foot

Back 30

saphenous n

Front 31

obturator N motor fxn

Back 31

mm of medial compartment of the thing (adductors)

Front 32

obturator N sensory

Back 32

skin over medial thigh

Front 33

exits the medial border of the psoas and continues by crossing into the pelvis and running along the lateral wall of the pelvis. It leaves the pelvis through a small defect in the obturator membrane over the obturator foramen. It immediately splits into an anterior divions, anterior to adductor brevis m and a posterior division, posterior to the adductor brevis m.

Back 33

obturator n

Front 34

result of lesion of obturator n

Back 34

weakened adduction

Front 35

What are the nerves of the gluteal region?

Back 35

superior gluteal N, inferior gluteal N, Nerve to obturator internus M, Nerve to quadratus femoris M, posterior femoral cutaneous N, pudendal N

Front 36

L4-S1

Back 36

superior gluteal N

Front 37

motor of superior gluteal N

Back 37

gluteus medius, gluteus minimus, tensor fascia lata (abductors and medial rotators of thigh)

Front 38

exits pelvis via the greater sciatic foramen, superior to the piriformis and courses bt gluteus medius and minimus

Back 38

superior gluteal N

Front 39

Result of lesion of superior gluteal N

Back 39

lack of support of the body on the femur and creates a positive Trendelenburg test

Front 40

L5-S2

Back 40

Inferior Gluteal N

Front 41

motor of inferior gluteal N

Back 41

gluteus maximus

Front 42

exits pelvis via greater sciatic foramen, inferior to piriformis and near the sciatic nerve

Back 42

inferior gluteal N

Front 43

result of lesion of inferior gluteal N

Back 43

reduce the power in the stride of walking

Front 44

mm innervated by femoral N

Back 44

iliacus, psoas major, quadriceps femoris (rectus femoris, vastus intermedius, vastus lateralis, vastus medialis), sartorius, pectineus

Front 45

mm innervated by obturator N

Back 45

adductor longus, adductor brevis, adductor magnus, gracilis, pectineus

Front 46

L5-S2

Back 46

N to obturator internus M and inferior gluteul N

Front 47

motor of N to obturator internus M

Back 47

obturator internus, superior gemellus

Front 48

exits pelvis via the greater sciatic foramen inferior to piriformis and then enters the perineum via the lesser sciatic foramen

Back 48

nerve to obturator internus muscle

Front 49

L5-S1

Back 49

N to quadratus femoris M

Front 50

motor of Nerve to quadratus femoris m

Back 50

quadratus femoris, inferor gemellus

Front 51

exits pelvis via the greater sciatic foramen deep to sciatic n

Back 51

Nerve to the quadratus femoris m

Front 52

S1-S3

Back 52

posterior femoral cutaneous nerve

Front 53

sensory of posterior femoral cutaneous n

Back 53

skin of inferior buttock and posterior thigh

Front 54

exits pelvis via the greater sciatic foramen inferior to the piriformis. It runs deep to the gluteus maximus until it exits from the inferior border and descends the posterior thigh

Back 54

posterior femoral cutaneous N

Front 55

S2-S4

Back 55

pudendal N

Front 56

branches of pudendal N

Back 56

inferior rectal
perineal
Dorsal n of the penis/clitoris

Front 57

motor to the external anal sphincter and sensory to the perianal skin

Back 57

inferior rectal N (branch of pudendal)

Front 58

motor though the deep branch that supplies the perineal mm and it supplies sensory fibers through the posterior scrotal/labial branches of the superficial perineal N

Back 58

perineal N (of pudendal N)

Front 59

sensory nn that innervate skin, prepuce, and glans of penis/clitoris

Back 59

dorsal N of the penis/clitoris (off pudendal N)

Front 60

exits pelvis via the greater sciatic foramen inferior to the piriformis and descends posterior to the sacrospinous ligament to enter the perineum through lesser sciatic formane and the pudendal canal

Back 60

pudendal n

Front 61

What are the nerves that become the sciatic N?

Back 61

lumbosacral trunk, sciatic N, tibial N, common fibular (peroneal) N

Front 62

What forms the sciatic N?

Back 62

lumbosacral trunk (L4-L5) combines with first three sacral segments

Front 63

forms on the internal surface of the piriformis m and exits to the gluteal region inferior to the piriformis in the greater sciatic foramen

Back 63

sciatic n

Front 64

contains both preaxial and post axial elements

Back 64

sciatic n

Front 65

What are the preaxial and postaxial parts of the sciatic n?

Back 65

preaxial: tibial n
postaxial: fibular n

Front 66

motor of sciatic N

Back 66

tibial: hamstrings (3 main mm of posterior compartment)
peroneal: short head of the biceps

Front 67

exits the pelvis via the greater sciatic foramen inferior to the piriformis. It descends bt the ischial tuberosity and the greater trochanter of the femur. It most often splits in the popliteal fossa to form the tibial n and the common fibular (perineal) n.

Back 67

sciatic n

Front 68

runs through popliteal fossa until it dives deep to the gaastrocnemius and soleus mm

Back 68

tibial N

Front 69

runs along the biceps femoris until it reaches the neck of the fibula

Back 69

common fibular n

Front 70

forms preaxial compnents of ventral rami of L4-S3

Back 70

tibial N

Front 71

motor of tibial N

Back 71

posterior compartment mm of leg

Front 72

sensory of tibial N

Back 72

cutaneous branches include the medial sural cutaneous N, which supplies the skin of the posterior leg and the lateral ankle, heel, and foot

Front 73

descends through the popliteal fossa and then dives deep to the gastrocnemius and soleus and runs close to the tibia. Courses into the foot bt the tendons of the flexor hallucis longus and flexor digitorum longus at the medial malleolus. Terminates after the ankle jt under flexor retinaculum by dividing into medial and lateral plantar nn

Back 73

tibial N

Front 74

motor of medial plantar N

Back 74

abductor hallucis, flexor digitorum brevis, flexor hallucis brevis, first lumbrical

Front 75

sensory of medial plantar n

Back 75

skin of lateral 1 and 1/2 toes

Front 76

motor of lateral plantar n

Back 76

abductor digit minimi, quadratus plantae, lateral 3 lumbrical, adductor hallucis, flexor digit minimi brevis, plantar and dorsal interossei mm

Front 77

sensory of lateral plantar n

Back 77

skin of lateral 1.5 toes

Front 78

postaxial elements of ventral rami of L4-S2

Back 78

common fibular (peroneal) N

Front 79

lesion of common fibular N

Back 79

weakened to absent eversion and foot drop

Front 80

motor of superficial fibular N

Back 80

2 mm of lateral compartment of leg, fibilaris (peroneus) longus and brevis

Front 81

sensory of superifical fibular N

Back 81

dorsum of foot except for skin at web bt the first and second digits

Front 82

motor of deep fibular N

Back 82

extensors and other mm of anterior compartment of leg and extensor digitorum brevis and extensor hallucis brevis

Front 83

sensory of deep fibular N

Back 83

web space bt big toe and second toe

Front 84

After passing through popliteal fossa and crossing superficial to the lateral head of the gastrocnemius, the nerve passes behind th ehead of the fibula and pierces th eproneus longus where it divides into the superfical and deep branches

Back 84

common fibular N

Front 85

This nerve is vulnerable as it wraps around the neck of the fibula

Back 85

common fibular N

Front 86

descends in the lateral compartment of the leg

Back 86

superfical fibular N

Front 87

enters the anterior compartment by passing through the extensor digitorum longus and descends on the interosseous membrane

Back 87

deep fibular