The quadriceps (or 'quads') muscle is the large muscle at the front of the thigh, and is composed of four heads.

quadriceps muscles


Illustration showing three of the heads of quadriceps. The fourth head - vastus intermedius - is not seen here as it lies underneath the rectus femoris.

rectus femoris component of the quadriceps muscle

The largest head - rectus femoris - reaches from the the pelvis to the tibia, with the patella forming an embedded component of the tendon.


Four heads

The term 'quadri-ceps' means 'four heads' - as the muscle has four separate components that join into a common tendon, the quads tendon. The four heads of the quads include:

  1. the central portion - the rectus femoris
  2. an inner portion - the vastus medialis
  3. an outer portion - the vastus lateralis
  4. a portion underneath the rectus femoris - the vastus intermedius

The muscles of the knee

Learn the names of the main knee muscles.