The Vasti
Origin =
Lateralis - Lateral portion of the femur extending from just beneath the greater tuberosity to the upper half of th elinea aspera of the femur.
Medialis - Entire length of the linea aspera.
Intermedius - Upper two-thirds of the femur from its anterior and lateral surfaces.
Insertion = On the patella by means of the tendon of the quadriceps femoris.
Action = Extension of the knee joint.