Contrary to some popular belief, the quadriceps is not a muscle. It is a group of muscles located in the front of the thigh, and it also goes by the name quadriceps femoris. The Latin translation of "quadriceps" indicates "four headed," as the group contains four separate muscles. Three of those muscles include the vastus lateralis, medialis and intermedius. Each of the vastus muscles originates on the femur bone and attaches to the patella, or kneecap. The three vastus muscles are also partially covered by the rectus femoris, which also attaches to the patella. However, unlike the vastus muscles, the rectus femoris inserts into the hip bone. As a whole, the quardriceps are served oxygenated blood from the lateral femoral circumflex artery and its branches. Also, the muscle group is innervated by the femoral nerve and its subsequent branches. The muscle groups assist in extending the knee. Since it used often for walking, running and other physical activities, the quadriceps are prone to injury involve strain, tears and other damage.
Written and medically reviewed by the Healthline Editorial Team
In Depth: Quadriceps femoris