Pelvis & Hip: Action

Question 1

Psoas major (Illiopasoas muscle)

Answer 1

Action: (With origin fixed) Flex the hip
Externally (laterally) rotate the hip
(With insertion fixed) Flex the trunk toward the thigh
Tilt pelvis anteriorly
(Unilaterally) Assist to laterally flex the lumbar spine

Question 2

Iliacus (Iliopasoas muscle)

Answer 2

Action: (with origin fixed) Flex the hip
Externally (laterally) rotate the hip
(with insertion fixed) Flex the trunk toward the thigh
Tilt pelvis anteriorly

Question 3

Gluteus Maximus

Answer 3

Action: (all fibers) Extend the hip
Externally (laterally) rotate the hip
Abduct the hip
(lower fibers) Adduct the hip

Origin: Coccyx, edge of the sacrum, posterior iliac crest, sacrotuberous and sacroiliac ligaments

Insertion: Iliotibial tract (upper fibers) and gluetal tuberosity (lower fibers)

Nerve Innervation: Inferior gluteal L5, S1 and S2

Question 4

Gluteus Medius

Answer 4

Action: (all fibers) Abduct the hip
(anterior fibers) Flex the hip
Internally (medially) rotate the hip
(posterior fibers) Extend the hip
Externally (laterally) rotate the hip

Question 5

Gluteus minimus

Answer 5

Action: Abduct the hip
Internally (medially) rotate the hip
Flex the hip

Question 6

Adductor magnus

Answer 6

Action: Adduct the hip
Internally (medially) rotate the hip
Assist to flex the hip
Internally (medially) rotate the flexed knee
(posterior fibers) Extend the hip

Question 7

Adductor longus

Answer 7

Action: Adduct the hip
Internally (medially) rotate the hip
Assist to flex the hip
Internally (medially) rotate the flexed knee

Question 8

Adductor brevis

Answer 8

Action: Adduct the hip
Internally (medially) rotate the hip
Assist to flex the hip
Internally (medially) rotate the flexed

Question 9

Pectineus

Answer 9

Action: Adduct the hip
Internally (medially) rotate the hip
Assist to flex the hip
Internally (medially) rotate the flexed knee

Question 10

Gracilis

Answer 10

Action: Adduct the hip
Internally (medially) rotate the hip
Flex the knee
Internally (medially) rotate the flexed knee

Question 11

Piriformis

Answer 11

Action: Externally (laterally) rotate the hip
Abduct the hip when the hip is flexed

Question 12

Quadratus femoris

Answer 12

Action: Externally (laterally) rotate the hip

Question 13

Obturator internus

Answer 13

Action: Externally (laterally) rotate the hip

Question 14

Obturator externus

Answer 14

Action: Externally (laterally) rotate the hip

Question 15

Gemellus superior

Answer 15

Action: Externally (laterally) rotate the hip

Question 16

Gemellus inferior

Answer 16

Action: Externally (laterally) rotate the hip