Muscles acting on the Thigh, Leg & Foot

Question 1

Psoas major

Answer 1

O- T12 & lumbar vertebrae; I- lesser trochanter of femur

Action- prime mover of thigh flexion

Question 2

Iliacus

Answer 2

O- iliac fossa & crest; I- lesser trochanter of femur

Action- prime mover of thigh flexion

Question 3

Iliopsoas muscles

Answer 3

Psoas major & iliacus

Question 4

Sartorius

Answer 4

O- anterior superior iliac spine; I- medial aspect of proximal tibia
Action- flexes, abducts, & laterally rotates thigh

Question 5

Tensor Fascia Lata

Answer 5

O- anterior iliac crest & anterior superior iliac spine; I- iliotibial band (IT band)
Action- flexes & abducts thigh; stabilizes leg by tightening IT band

Question 6

Adductor longus

Answer 6

O- pubis (near symphysis); I- linea aspera of femur

Action- adducts & medially rotates thigh

Question 7

Adductor magnus

Answer 7

O- ischial tuberosity; I- linea aspera of femur

Action- adducts & medially rotates thigh

Question 8

Gracilis

Answer 8

O- pubis; I- medial surface of tibia (near medial condyle)

Action- adducts & medially rotates thigh

Question 9

Gluteus maximus

Answer 9

O- posterior ilium, sacrum, coccyx; I- gluteal tuberosity of femur and IT band
Action- extends thigh

Question 10

Gluteus medius

Answer 10

O- lateral surface of ilium; I- greater trochanter of femur

Action- abducts and medially rotates thigh

Question 11

Quadriceps Femoris (name the 4 muscles)

Answer 11

Rectus femoris, vastus lateralis, vastus intermedius, vastus medialis

Question 12

Rectus femoris

Answer 12

O- anterior inferior iliac spine; I- patella & tibial tuberosity via patellar ligament and tendon of quadriceps femoris
Action- flex thigh and extends leg

Question 13

Vastus Lateralis

Answer 13

O- greater trochanter, linea aspera, intertrochanteric line; I- patella & tibial tuberosity via patellar ligament and tendon of quadriceps femoris
Action- extends leg

Question 14

Vastus intermedius

Answer 14

O- proximal femur shaft; I- patella & tibial tuberosity via patellar ligament and tendon of quadriceps femoris
Action- extends leg

Question 15

Vastus medialis

Answer 15

O- linea aspera; I- patella & tibial tuberosity via patellar ligament and tendon of quadriceps femoris
Action- extends leg

Question 16

Hamstrings (name 3 muscles)

Answer 16

Biceps femoris, semitendinosus, semimembranosus

Question 17

Biceps femoris

Answer 17

O- ischial tuberosity; I- common tendon that inserts into head of fibula & lateral condyle of tibia
Action- extend the thigh and flex the leg

Question 18

Semitendinosus

Answer 18

O- ischial tuberosity; I- medial aspect of tibia

Action- extend the thigh and flex the leg

Question 19

Semimembranosus

Answer 19

O- ischial tuberosity; I- medial condyle of tibia & lateral condyle of femur
Action- extend the thigh and flex the leg

Question 20

Tibialis Anterior

Answer 20

O- lateral condyle & shaft of tibia; I- medial cuneiform & metatarsal I
Action- dorsiflexes and inverts foot

Question 21

Extensor digitorum longus

Answer 21

O- lateral condyle of tibia & proximal shaft of fibula; I- middle and distal phalanges of digits II-V
Action- extends toes

Question 22

Fibularis longus

Answer 22

O- lateral, proximal fibula; I- medial cuneiform & metatarsal I (via tendon that curves under the foot)
Action- plantar flexes & everts foot

Question 23

Gastrocnemius

Answer 23

O- medial & lateral condyles of femur (via 2 heads); I- posterior calcaneus (via calcaneal tendon)
Action- plantar flexes the foot

Question 24

Soleus

Answer 24

O-proximal tibia & fibula; I- posterior calcaneus (via calcaneal tendon)
Action- plantar flexes the foot

Question 25

Common insertion for thigh adductors

Answer 25

Linea aspera of femur

Question 26

Common insertion for quadriceps

Answer 26

Patella & tibial tuberosity via patellar ligament

Question 27

Common origin for hamstrings

Answer 27

Ischial tuberosity