The important anatomical structures of the knee joint include bone, ligaments, tendons and cartilage. The “femur” is a large bone of the thigh, the “tibia” is a large bone of the lower leg, the “fibula” is a thin bone of the non-cranial lower leg, and the patella, also called the The patella, also called the “kneecap,” is about 5-6 cm wide and 6-7 cm high, and is located in front of the other two bones of the knee joint. There are two ligaments on either side of the knee, the “medial collateral ligament” and the “lateral collateral ligament”. Inside the knee joint, there are two ligaments that connect the femur and tibia, the anterior cruciate ligament and the posterior cruciate ligament, which are also called the anterior cruciate ligament because they cross in the direction of travel in the shape of a cross. They are called “anterior cruciate ligament” and “posterior cruciate ligament”. Of course, the anterior cruciate ligament is in the front and the posterior cruciate ligament is in the back in terms of anterior-posterior direction. The difference between the ligament and the tendon is that the ligament is the tissue that connects the bone to the bone, while the tendon is the tissue that connects the muscle to the bone, and both work together to maintain the stability of the joint. The meniscus is located between the femur and the trabecular bone and can be thought of as the “cushion” in the knee joint. The meniscus is essentially a cartilage tissue, but it is fibrocartilage, unlike articular cartilage, which is hyaline cartilage. Articular cartilage is a special material that covers the two bony ends of a joint and is white, translucent, shiny, elastic and hard. The function of articular cartilage is to absorb oscillations and to provide an extremely smooth loading surface for normal joint movement. In the knee joint, the articular cartilage covers the lower femur, the upper tibia and the back of the patella. The knee joint has two groups of muscles. The quadriceps, located in front of the femur, consists of four muscles that serve to straighten the leg; the N cord muscle is behind the femur and extends from the arm to just below the knee joint and serves to flex the knee joint.