Vastus lateralis muscle

The vastus lateralis muscle is one of the four muscles that comprise the quadriceps femoris group, located in the anterior compartment of the thigh. It is the largest and most lateral of the quadriceps muscles. The vastus lateralis originates from several sites: the greater trochanter, the lateral lip of the linea aspera, and the lateral intermuscular septum. It inserts into the lateral base and border of the patella and the patellar ligament, which continues to the tibial tuberosity.

Origin: Greater trochanter, Intertrochanteric line, and linea aspera of the femur

Insertion: patella via the tendon of quadriceps femoris and tibial tuberosity via the patellar ligament

Artery: Femoral artery

Nerve: Femoral nerve

Action: Extends and stabilizes knee

Antagonist: Hamstring

Muscle group: Anterior compartment of thigh

Description: The Vastus lateralis (Vastus externus) is the largest part of the Quadriceps femoris. Itarises by a broad aponeurosis, which is attached to the upper part of the intertrochanteric line, to the anterior and inferior borders of the greater trochanter, to the lateral lip of the gluteal tuberosity, and to the upper half of the lateral lip of the linea aspera; this aponeurosis covers the upper three-fourths of the muscle, and from its deep surface many fibers take origin. A few additional fibers arise from the tendon of the Glutaeus maximus, and from the lateral intermuscular septum between the Vastus lateralis and short head of the Biceps femoris. The fibers form a large fleshy mass, which is attached to a strong aponeurosis, placed on the deep surface of the lower part of the muscle: this aponeurosis becomescontracted and thickened into a flat tendon inserted into the lateral border of the patella, blending with the Quadriceps femoris tendon, and giving an expansion to the capsule of the knee-joint. The Vastus medialis and Vastus intermedius appear to be inseparably united, but when the Rectus femoris has been reflected a narrow interval will be observed extending upward from the medial border of the patella between the two muscles, and the separation may be continued as far as the lower part of the intertrochanteric line, where, however, the two muscles are frequently continuous.