**2. Functional anatomy of the knee joint**

The knee joint is the largest synovial-type and most-stressed joint in the body. This modified hinge joint is composed of two articulations; the **tibiofemoral** and patellofemoral. The structural and functional stability of the knee joint comes from the muscles and ligaments attached, which also helps to bear considerable biomechanical stress brought upon the joint. Furthermore, the patella acts as an anatomical pulley for the quadricep muscles [3], which enhances knee joint extension by allowing frictionless movements, stabilizes and protects the knee joint. In addition, the joint cartilage and the menisci provide intraarticular flexibility, cushioning, and shock absorption.
