The quadriceps femoris (quadriceps extensor, or quads) consists of four muscles on the front of the thigh: the rectus femoris, the vastus medialis, the vastus lateralis, and the vastus intermedius. These muscles contain predominantly type II (fast-twitch) muscle fibres. Its main action is to extend or straighten the knee.

• Overstretching or forceful contraction such as in sprinting jumping.
• The rectus femoris muscle is particularly susceptible to injury as it passes over two joints,
  the hip and the knee.

• A stab of intense pain as the injury occurs during activity.
• The muscle may go into spasm.
• Intense tenderness over the injured area.
• Swelling may occur.
• Pain can be elicited by contracting the muscle against resistance.
• A defect can be felt in the muscle in cases of a complete or major partial tear.

Under the direction of your medical professional and in conjunction with your advised treatment plan, either of the following Thermoskin products is recommended: