1502
The quadriceps femoris, also called the quadriceps extensor, quadriceps or quads.
It is a large muscle group that includes the four prevailing muscles on the front of the thigh.
Quadriceps femoris muscle.
rectus femoris
vastus lateralis
vastus intermedius
vastus medialis
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:
Rectus femoris occupies the middle of the thigh, covering most of the other three quadriceps muscles.
It originates on the ilium.
The other three muscles lie deep to rectus femoris and originate from the body of the femur, which they cover from the trochanters to the condyles.
The Vastus lateralis is on the lateral side of the femur.
The Vastus medialis is on the medial side of the femur
The Vastus intermedius lies between vastus lateralis and vastus medialis on the front of the femur, but deep to the rectus femoris.
All four parts of the quadriceps muscle ultimately insert into the tuberosity of the tibia via the patella, where the quadriceps tendon becomes the patellar ligament.
There is a fifth muscle of the quadriceps complex that is rarely taught called articularis genus, and the presence of a sixth muscle, the tensor vastus intermedius.
The muscle 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.
All four quadriceps are powerful extensors of the knee joint, necessary in walking, running, jumping and squatting.
Because rectus femoris attaches to the ilium, it is also a flexor of the hip, and crucial to walking or running as it swings the leg forward into the ensuing step.
The quadriceps, specifically the vastus medialis, play the important role of stabilizing the patella and the knee joint during gait.
Effective exercises include the squat and leg press.
The isolation movement is the leg extension exercise that targets solely the quadriceps