Thigh

Question 1

Sartorius

Answer 1

Origin: anterior superior iliac spine
Insertion: upper medial surface of shaft of tibia
Nerve: femoral nerve
Action: flexes, abducts, and laterally rotates thigh at hip joint; flexes and medially rotates leg at knee joint

Question 2

Iliacus

Answer 2

Origin: iliac fossa of hip bone
Insertion: with psoas into lesser trochanter of femur
Nerve: femoral nerve
Action: flexes thigh on trunk; if thigh is fixed, it flexes the trunk on the thigh as in sitting up from lying down

Question 3

Psoas

Answer 3

Origin: transverse processes; bodies, and intervertebral discs of 12th thoracic and five lumbar vertebrae
Insertion: with iliacus with lesser trochanter of femur
Nerve: lumbar plexus
Action: flexes thigh on trunk; if thigh is fixed it flexes trunk on the thigh as in sitting up from lying down

Question 4

Pectineus

Answer 4

Origin: superior ramus of pubis
Insertion: upper end of linea aspera of shaft of femur
Nerve: femoral nerve
Action: flexes and adducts thigh at hip joint

Question 5

Rectus Femoris

Answer 5

Origin: straight head- anterior inferior iliac spine; reflected head-ilium above acetabulum
Insertion: quadriceps tendon into patella; then via ligamentum patellae into tubercle of tibia
Nerve: femoral nerve
Action: extension of leg at knee joint; flexes thigh at hip joint

Question 6

Vastus Lateralis

Answer 6

Origin: upper end and shaft of femur
Insertion: quadriceps tendon into patella; then via ligamentum patellae into tubercle of tibia
Nerve: femoral nerve
Action: extension of leg at knee joint

Question 7

Vastus Medius

Answer 7

Origin: upper end and shaft of femur
Insertion: quadriceps tendon into patella; then via ligamentum patellae into tubercle of tibia
Nerve: femoral nerve
Action: extension of leg at knee joint; stabilizes patella

Question 8

Vastus Intermedius

Answer 8

Origin: anterior and lateral surface of shaft of femur
Insertion: quadriceps tendon into patella; then via ligamentum patellae into tubercle of tibia
Nerve: femoral nerve
Action: extension of leg at knee joint; articularis genus retracts synovial membrane

Question 9

Gracilis

Answer 9

Origin: inferior ramus of pubis; ramus of ischium
Insertion: upper part of shaft of tibia on medial surface
Nerve: obturator nerve
Action: adducts thigh at hip joint; flexes leg at knee joint

Question 10

Adductor Longus

Answer 10

Origin: body of pubis; medial to pubic tubercle
Insertion: posterior surface of shaft of femur (linea aspera)
Nerve: obturator nerve
Action: adducts thigh at hip joint; assists in lateral rotation

Question 11

Adductor Brevis

Answer 11

Origin: inferior ramus of pubis
Insertion: posterior surface of shaft of femur (linea aspera)
Nerve: obturator nerve
Action: adducts thigh at hip joint and assists in lateral rotation

Question 12

Adductor Magnus

Answer 12

Origin: inferior ramus of pubis; ramus of ischium; ischial tuberosity
Insertion: posterior surface of shaft of femur; adductor tubercle of femur
Nerve: adductor portion- obturator nerve; hamstring portion- sciatic nerve
Action: adducts thigh at hip joint and assists in lateral rotation; hamstring portion extends thigh at hip joint

Question 13

Obturator Externus

Answer 13

Origin: outer surface of obturator membrane and pubis and ischial rami
Insertion: medial surface of greater trochanter
Nerve: obturator nerve
Action: laterally rotates thigh at hip joint

Question 13

Biceps Femoris

Answer 13

Origin: long head- ischial tuberosity; short head- linea aspera, lateral supracondylar ridge of shaft of femur
Insertion: head of fibula
Nerve: long head- tibial portion of sciatic nerve; short head- common peroneal portion of sciatic nerve
Action: flexes and laterally rotates leg at knee joint; long head also extends thigh at hip joint

Question 14

Semitendinosus

Answer 14

Origin: ischial tuberosity
Insertion: upper part of medial surface of shaft of tibia
Nerve: tibial portion of sciatic nerve
Action: flexes and medially rotates leg at knee joint; extends thigh at hip joint

Question 15

Semimembranosus

Answer 15

Origin: ischial tuberosity
Insertion: medial condyle of tibia
Nerve: tibial portion of sciatic nerve
Action: flexes and medially rotates leg at knee joint; extends thigh at hip joint

Question 16

Adductor Magnus (Hamstring Portion)

Answer 16

Origin: ischial tuberosity
Insertion: adductor tubercle of femur
Nerve: tibial portion of sciatic nerve
Action: extends thigh at hip joint