Rectus femoris muscle

The rectus femoris muscle (/ˈrɛktəs ˈfɛmərᵻs/) is one of the four quadriceps muscles of the human body. The others are the vastus medialis, the vastus intermedius (deep to the rectus femoris), and the vastus lateralis. All four parts of the quadriceps muscle attach to the patella (knee cap) via the quadriceps tendon.