Lower Extremities Qs

Question 1

What innervates the pectineus?

Answer 1

Femoral nerve (L2, L3)

Question 2

What is the action of the pectineus?

Answer 2

Adducts and flexes thigh; assists with medial rotation

Question 3

What innervates the iliopsoas?

Answer 3

Anterior rami fo lumbar nerves (L1, L2, L3)

Question 4

What muscle stabilizes the hip joint?

Answer 4

Iliopsoas - also main hip flexor

Question 5

What innervates the sartorius?

Answer 5

Femoral nerve (L2, L3)

Question 6

What is the action of the sartorius?

Answer 6

Flexes, abducts, and laterally rotates at hip joint

Question 7

The quadriceps femoris is composed of which four muscles?

Answer 7

Rectus femoris

vastus lateralis

vastus medialis

vastus intermedius

Question 8

What innervates the rectus femoris?

Answer 8

Femoral nerve (L2, L3)

Question 9

What innervates the vastus lateralis?

Answer 9

Femoral nerve (L2, L3)

Question 10

What innervates the vastus medialis?

Answer 10

Femoral nerve (L2, L3)

Question 11

What innervates the vastus intermedius?

Answer 11

Femoral nerve (L2, L3)

Question 12

What is the action of the quadriceps femoris?

Answer 12

Knee extensor

Flexes thigh

Steadies hip joint

Question 13

The hamstrings are composed of which three muscles?

Answer 13

Semitendinosus

Semimembranosus

Biceps femoris

Question 14

What innervates the adductor longus?

Answer 14

Anterior division of obturator nerve (L2, L3, L4)

Question 15

What innervates the adductor brevis?

Answer 15

Anterior and posterior branches of the obturator nerves (L2, L3, L4)

Question 16

What innervates the adductor magnus?

Answer 16

Adductor part by posterior division of obturator nerve; hamstring part by tibial part of sciatic nerve (L4)

Question 17

What is the action of the adductor longus?

Answer 17

Flexes thigh

Question 18

What is the action of the adductor brevis?

Answer 18

Flexes thigh

Question 19

What is the action of the adductor magnus?

Answer 19

Flexes thigh

Question 20

What innervates the gracilis?

Answer 20

Obturator nerve (L2, L3)

Question 21

What innervates the obturator externus?

Answer 21

Obturator nerve (L3, L4)

Question 22

What is the action of the gracilis?

Answer 22

Flexes leg

Medially rotates leg

Question 23

What is the action of the obturator externus on the thigh?

Answer 23

Lateral rotation

Question 24

What innervates the semitendinosus?

Answer 24

Tibial division of sciatic nerve part of tibia (L5, S1, S2)

Question 25

What innervates the semimembranosus?

Answer 25

Tibial division of sciatic nerve part of tibia (L5, S1, S2)

Question 26

What innervates the biceps femoris?

Answer 26

Tibial division of sciatic nerve for the long head; common fibular division of sciatic nerve for short head

Question 27

What is the action of the semitendinosus?

Answer 27

Extends the trunk when flexed

Question 28

What is the action of the semimembranosus?

Answer 28

Extends the trunk when flexed

Question 29

What innervates the gluteus maximus?

Answer 29

Inferior gluteal nerve (L5, S1, S2)

Question 30

What innervates the gluteus medius?

Answer 30

Superior gluteal nerve (L5, S1)

Question 31

What is the action of the gluteus maximus?

Answer 31

Abducts and rotates the thigh

Question 32

What is the action of the gluteus medius?

Answer 32

Abducts and rotates the thigh

Question 33

What innervates the tibialis anterior?

Answer 33

Deep fibular nerve (L4, L5)

Question 34

What innervates the extensor digitorum longus?

Answer 34

Deep fibular nerve (L4, L5)

Question 35

What innervates the extensor hallucis longus?

Answer 35

Deep fibular nerve (L4, L5)

Question 36

What innervates the fibularis/peroneus tertius?

Answer 36

Deep fibular nerve (L4, L5)

Question 37

What is the action of the tibialis anterior?

Answer 37

Inverts foot

Question 38

What is the action of the extensor digitorum longus?

Answer 38

Extends lateral four digits

Question 39

What is the action of the extensor hallucis longus?

Answer 39

Extends great toe

Question 40

What is the action of the fibularis/peroneus tertius?

Answer 40

Everts foot

Question 41

In what compartment of the leg can you find the fibularis/peroneus longus and brevis?

Answer 41

Lateral compartment of the leg

Question 42

What innervates the fibularis/peroneus longus and brevis?

Answer 42

Superficial fibular nerve (L5, S1, S2)

Question 43

What is the action of the fibularis/peroneus longus and brevis?

Answer 43

Weak plantarflexion of ankle

Question 44

Give three superficial muscles reponsible for ankle plantarflexion.

Answer 44

Gastrocnemius, soleus, plantaris

Question 45

Give four deep muscles found in the posterior compartment of the leg.

Answer 45

Popliteus, flexor hallucis longus, flexor digitorum longus, tibialis posterior

Question 46

What innervates the abductor hallucis and flexor digitorum brevis?

Answer 46

Medial plantar nerve (S2, S3)

Question 47

In which layer of the sole can you find the lumbricals?

Answer 47

2nd layer

Question 48

What is the action of the flexor hallucis brevis?

Answer 48

Flexes proximal phalanx of 1st digit

Question 49

Which digits are adducted by the plantar interossei?

Answer 49

3rd to 5th

Question 50

Give two muscles that extend the foot.

Answer 50

Extensor digitorum brevis, extensor hallucis brevis

Question 51

components of the Pes anserinus

Answer 51

From medial to lateral:

Sartorius

Gracilis

Semitendinosus

“Some Great Tendons”