Muscles of the Anterior Thigh (Extensors of the Knee)

Question 1

Rectus Femoris M.

Answer 1

Origin: Anterior Inferior Iliac Spine + Body of Ileum (above acetabulum)

Insertion: quadriceps tendon to the base of the patellar ligament

Action: flex the thigh, extend the leg at the knee joint

Innervation: Femoral Nerve (L2,L3,L4)

Question 2

Vastus Lateralis M.

Answer 2

Origin: Lateral lip of linea aspera & greater trochanter of the femur

Insertion: quadriceps tendon that goes to the base of the patellar ligament

Innervation: Femoral Nerve (L2, L3, L4)

Action: extend the leg at the knee joint

Question 3

Vastus Medialis M.

Answer 3

Origin: intertrochanteric line & medial lip of the linea aspera of the femur

Insertion: quadriceps tendon to the patellar ligament

Innervation: Femoral Nerve (L2, L3, L4)

Action: Extend the leg at the knee joint

Question 4

Vastus Intermedius M.

Answer 4

Origin: Anterior and Lateral Shaft of the Femur

Insertion: Quadriceps Tendon to the patellar ligament

Innervation: Femoral Nerve (L2, L3, L4)

Action: extend the leg at the knee joint