Muscles Crossing the Hip and Knee Joints

Question 1

Iliacus (Anterior Muscle)

Answer 1

Origin: Iliac fossa and crest, ala of sacrum
Insertion: Lesser trochanter of femur via iliopsoas tendon
Action: Prime mover for flexing thigh or for flexing trunk on thigh; hip flexion
Innervated by the femoral nerve L2-L3

Question 2

Psoas Major (Anterior Muscle)

Answer 2

Origin: Transverse processes, bodies and discs of lumbar vertebrae and T12-L5
Insertion: Lesser trochanter of femur via iliopsoas tendon
Action: Prime mover for flexing thigh or for flexing trunk on thigh; hip flexion; flexes vertebral column laterally
Innervated by the ventral rami L1-L3

Question 3

Sartorius (Anterior Muscle)

Answer 3

Origin: Anterior superior iliac spine
Insertion: Upper medial tibia
Action: Flexes, abducts and laterally rotates thigh; helps produces cross-legged position
Innervated by the femoral nerve

Question 4

Rectus Femoris (Anterior Muscle)

Answer 4

Origin: Anterior inferior iliac spine and superior margin of acetabulum
Insertion: Patella and tibial tuberosity via patellar ligament
Action: Extends knee and flexes thigh at hip
Innervated by the femoral nerve

Question 5

Vastus Lateralis (Anterior Muscle)

Answer 5

Origin: Greater trochanter, intertrochanteric line, linea aspera
Insertion: Patella and tibial tuberosity via patellar ligament
Action: Extends and stabilizes knee
Innervated by the femoral nerve

Question 6

Vastus Medialis (Anterior Muscle)

Answer 6

Origin: Linea aspera, intertrochanteric and medial supracondylar lines
Insertion: Patella and tibia tuberosity via patellar ligament
Action: Extends knee
Innervated by the femoral nerve

Question 7

Vastus Intermedius (Anterior Muscle)

Answer 7

Origin: Anterior and lateral surfaces of proximal femur shaft
Insertion: Patella and tibia tuberosity via patellar ligament
Action: Extends Knee
Innervated by the femoral nerve

Question 8

Tensor Fasciae Latae (Anterior Muscle)

Answer 8

Origin: Anterior aspect of iliac crest and anterior superior iliac spine
Insertion: iliotibial tract
Action: Flexes and abducts thigh; rotates thigh medially; steadies the knee and trunk on thigh by making iliotibial tract taut

Question 9

Adductor Magnus (Medial Muscle)

Answer 9

Origin: Ischial and pubic rami and ischial tuberosity
Insertion: Linea aspera and adductor tubercle of fermur
Action: Adduction, medially rotates, and flexes the thigh; active gait and posturel extends thigh
Innervated by the obturator nerve and sciatic L2-L4 (tibial portion) nerve

Question 10

Adductor Longus (Medial Muscle)

Answer 10

Origin: Pubis near pubic symphysis
Insertion: Linea aspera
Action: Adducts, flexes, and medially rotates thigh
Innervated by the obturator nerve L2-L4

Question 11

Adductor Brevis (Medial Muscle)

Answer 11

Origin: Body and inferior pubic ramus
Insertion: Linea aspera above adductor longus
Action: Adducts, flexes, and medially rotates thigh
Innervated by the obturator nerve

Question 12

Pectineus

Answer 12

Origin: Pectineal line of pubis and superior ramus
Insertion: From lesser trochanter inferior to the linea aspera on posterior aspect of femur
Action: Adducts, flexes, and medially rotates thigh
Innervated by the femoral nerve

Question 13

Gracilis

Answer 13

Origin: inferior ramus and body of pubis and adjacent ischial rams
Insertion: upper medial surface of tibia
Action: Adducts thigh, flexes, and medially rotates leg
Innervated by the obturator nerve