Quadriceps

Quadriceps femoris muscle
Quadriceps femoris, with different muscles in different colors. rectus femoris - blue vastus lateralis - yellow vastus intermedius - green vastus medialis - red
Details
Origin	Combined rectus femoris and vastus muscles
Insertion	Tibial tuberosity
Artery	Femoral artery
Nerve	Femoral nerve
Actions	Knee extension; Hip flexion (Rectus femoris only)
Identifiers
Latin	Musculus quadriceps femoris
TA	A04.7.02.017
FMA	22428
Anatomical terms of muscle []

The quadriceps femoris (/ˈkwɒdrᵻsɛps ˈfɛmərᵻs/) (Latin for "four-headed muscle of the femur"), also called simply the quadriceps, quadriceps extensor, or quads, is a large muscle group that includes the four prevailing muscles on the front of the thigh.

It is the great extensor muscle of the knee, forming a large fleshy mass which covers the front and sides of the femur.

It is subdivided into four separate portions or 'heads', which have received distinctive names:

All four parts of the quadriceps muscle ultimately insert into the tuberosity of the tibia. This is via the patella, where the quadriceps tendon becomes the patellar ligament, which then attaches to the tibia.

There is a fifth muscle of the quadriceps complex that is often forgotten and rarely taught called articularis genus.

In addition, recent cadaver studies have confirmed the presence of a sixth muscle, the tensor vastus intermedius. While the muscle has variable presentations, it consistently originates at the proximal femur, runs between the vastus lateralis and vastus intermedius muscles, and inserts distally at the medial aspect of the patellar base. Historically considered a part of the vastus lateralis, the tensor vastus intermedius muscle is innervated by an independent branch of the femoral nerve and its tendinous belly can be separated from the vasti lateralis and intermedius muscles in most cases.