This image shows the structure of the knee joint, which is made up of several bones and cartilage structures. The bones are the tibia and fibula, which are the two bones in the lower leg. The cartilage structures include the meniscus and the patellar tendon, which connect the bones together. The meniscus is a shock absorbing cartilage structure in the knee joint that helps to cushion the bones as they move. The patellar tendon connects the quadriceps muscle to the patella, which is the small bone at the front of the knee joint.