Knee joints

The other two knee joints are the tibiofibular joint is formed by the outside part of one of your leg bones (tibia) forming a joint with the head of your other leg bone, your fibular. This joint bears about one sixth of your weight and resists twisting movements of your ankle.

The third joint is formed between the undersurface of your kneecap, or patella, and your femur, called your patellofemoral joint. Your kneecap is a triangular shaped bone embedded within the tendon of your front thigh muscles, the quadriceps muscles (so named because it is made up of four muscles). It acts as a pivot by increasing the power of your quadriceps by about 30% and is the largest “pivot” bone in your body. The greatest force, and therefore the greatest source of wear and tear, acting on your kneecap is from your quadriceps.