The quadriceps muscle group consists of four muscles: the rectus femoris, the vastus lateralis, the vastus intermedius, and the vastus medialis. They form a large fleshy mass that covers the front and sides of the femur and work as the primary extensor of the knee. Research Quadriceps
The rectus femoris is one of the four bellies of the quadriceps muscle group. The quadriceps muscle group consists of four muscles: the rectus femoris, the vastus lateralis, the vastus intermedius, and the vastus medialis. The rectus femoris is a large fleshy mass that originates at the back of the inferior iliac spine and covers the front and sides of the femur. It inserts in the top of the patella. This muscle is innervated by the femoral nerve and supplied by the circumflex artery. The quadricep muscles work together as the primary extensor of the knee. The rectus femoris is the only two- joint muscle in the group, crossing both the knee and the hip joint. This long, flat muscle extends the leg at the knee joint and flexes the thigh at the hip joint. When the rectus femoris is contracted, the knee joint is straightened and the lower leg is extended. When it is relaxed, the lower leg is flexed. Research Rectus Femoris
The vastus intermedius (femoral muscle; crureas) is an extensive muscle that lies deep to all the other quadriceps bellies, adding muscular fullness under them. It originates from the anterior shaft of the femur and inserts in the tuberosity of the tibia with the tendon of the quadriceps femoris and the patellar ligaments. It is innervated by the femoral nerve and supplied by femoral circumflex artery. The quadricepsmuscles consist of: the rectus femoris, the vastus lateralis, the vastus intermedius, and the vastus medialis. These muscles form a large fleshy mass that covers the front and sides of the femur. They work together as the primary extensor of the knee. Research Vastus Intermedius
The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
Abbreviations
Research Quadriceps
