The quadriceps muscle group is located in which region of the leg?

• A. Posterior thigh muscles
• B. Calf muscles
• C. Shoulder girdle muscles
• D. Anterior thigh muscles

Answer: (D)

The quadriceps are located in the anterior thigh—the front part of the leg. This large group of four muscles (rectus femoris and the three vastus muscles) sits in the front compartment of the thigh and primarily acts to extend the knee. That front-of-thigh position distinguishes them from other leg regions: the posterior thigh houses the hamstrings (back of the thigh, knee flexion), the calf muscles are in the lower leg, and the shoulder girdle muscles are up in the shoulder region. So the correct region is the front of the thigh, the anterior thigh.