Vastus medialis

The vastus medialis (Latin: musculus vastus medialis) is one of four muscles that compose one of the strongest muscle in the human body - the quadriceps femoris muscle. It is located on the medial side in the anterior compartment of the thigh, and therefore, it belongs to the thigh muscle group. The vastus medialis originates from several anatomical landmarks of the femur, descends and via a tendon common with all quadriceps femoris muscles inserts on the tibial tuberosity of the tibia.

Origin

The vastus medialis originates from the lower aspect of the intertrochanteric line and the spiral line of the femur, as well as from the medial lip of the linea aspera and superior aspect of the medial supracondylar ridge of the femur.

Insertion

Along with other muscles of the quadriceps femoris, the vastus medialis inserts on the tibial tuberosity via the patellar ligament. Also, it attaches to the medial aspect of the patella.

Action

Like other muscles composing the quadriceps femoris muscle, the vastus medialis extends the leg at the knee joint.

Innervation

The vastus medialis is innervated by the muscular branches of the femoral nerve (L2 - L4) that arises from the lumbar plexus.

Blood supply

The vastus medialis receives arterial blood supply from the femoral, deep femoral and superior medial genicular arteries. The femoral artery is a continuation of the external iliac artery, the deep femoral artery arises from the femoral, while the superior medial genicular artery is a branch of the popliteal artery.