Muscles and Actions of the Leg

Question 1

What are the 7 leg muscles that PLANTAR FLEX the ankle?

Answer 1

1. gastrocnemius (when the knee is extended; also raises heel during walking and flexes leg @ knee joint)
2. soleus (independent of knee position; also steadies leg on foot)
3. flexor digitorum longus
4. tibialis posterior
5. flexor hallucis longus (weakly)
6. fibularis longus (weakly)
7. fibularis brevis (weakly)

Question 2

What are the 3 leg muscles that EVERT the foot?

Answer 2

1. fibularis longus
2. fibularis brevis
3. fibularis tertius

Question 3

What are the 2 leg muscles that INVERT the foot?

Answer 3

1. Tibialis Anterior

2. Tibialis Posterior

Question 4

What are the 4 leg muscles that DORSI FLEX the ankle?

Answer 4

1. Tibialis Anterior
2. Extensor digitorum longus
3. Extensor hallucis longus
4. Fibularis tertius

Question 5

What are the 2 muscles that flex and extend the GREAT TOE?

Answer 5

Flexor hallucis longus and Extensor hallucis longus

Question 6

What are the 2 muscles that flex and extend the LATERAL 4 DIGITS?

Answer 6

Flexor digitorum longus and Extensor digitorum longus

Question 7

What are the muscles that support the longitudinal arches of the foot?

Answer 7

Flexor digitorum longus

The flexor hallucis longus and Tibialis posterior support the the MEDIAL longitudinal arch

Question 8

Which muscle weakly FLEXES the KNEE?

Answer 8

Popliteus (also unlocks the knee)

Question 9

Which muscle assists the GASTROCNEMIUS in plantar flexion?

Answer 9

Plantaris

Question 10

Which 5 leg muscles function in the ADDUCTION of the THIGH?

Answer 10

1. gracilis (also flexes + medially rotates the leg)
2. pectineus (also flexes and medially rotates the thigh)
3. adductor longus
4. adductor brevis
5. adductor magnus (the hamstring part extends the thigh)

Question 11

Which 8 leg muscles function in ABDUCTION and FLEXES the thigh?

Answer 11

3 muscles also medially rotate the thigh:

• tensor fascia lata
• gluteus medius and gluteus minimus (these 2 muscles do not flex the thigh)

5 muscles also laterally rotates the thigh:

• sartorius (also flexes the leg)
• piriformis
• obturator internus
• superior and inferior gemellus

Question 12

Which 6 muscles laterally rotate the thigh and steadies the head of the femur in the acetabulum?

Answer 12

1. quadratus femorus
2. obturator externus
3. obturator internus (also abducts/flexes thigh)
4. piriformis (also abducts/flexes thigh)
5. superior gemellus (also abducts/flexes thigh)
6. inferior gemellus (also abducts/flexes thigh)

Question 13

Which muscles EXTENDS THE LEG?

Answer 13

Quadriceps femoris:

1. rectus femoris (also steadies hip joint and helps iliopsoas to flex the thigh)
2. vastus lateralis
3. vastus medialis
4. vastus intermedius

Question 14

Which muscles both EXTEND the THIGH and FLEX the leg?

Answer 14

• semitendinosus and semimembranosus (rotates leg medially)

- biceps femoris (rotates leg laterally)

Question 15

Which muscles function to EXTEND the THIGH and rotate the thigh laterally

Answer 15

gluteus Maximus

Question 16

Which muscle FLEXES the thigh at the hip joint?

Answer 16

Iliopsoas muscles