ANATOMY

Detailed explanation-1: -The vastus lateralis muscle is located on the lateral side of the thigh. This muscle is the largest of the quadriceps which includes: rectus femoris, vastus intermedius, and vastus medialis.

Detailed explanation-2: -The three muscles are the vastus intermedius, the vastus lateralis, and the vastus medialis located in the middle, on the outside, and inside of the thigh, respectively. The fourth muscle is the rectus femoris muscle a large fleshy muscle which covers the front and sides of the femur.

Detailed explanation-3: -Vastus medialis is one of the four muscles that make up the quadriceps group of muscles. It originates from the upper part of the femoral shaft and inserts as a flattened tendon into the quadriceps femoris tendon, which inserts into the upper border of the patella.

Detailed explanation-4: -The vastus lateralis (/ˈvæstəs ˌlætəˈreɪlɪs, ˈræ-/), also called the vastus externus, is the largest and most powerful part of the quadriceps femoris, a muscle in the thigh. Together with other muscles of the quadriceps group, it serves to extend the knee joint, moving the lower leg forward.

Detailed explanation-5: -Rectus Femoris It runs straight down the leg (the Latin for straight is rectus), and attaches to the patella by the quadriceps femoris tendon. Actions: The only muscle of the quadriceps to cross both the hip and knee joints. It flexes the thigh at the hip joint, and extends at the knee joint.