The knee is a sophisticated design with three long leg bones (tibia, fibula, and femur), and join them at the knee cap. Now add several connecting ligaments and muscles to make it move and to ensure joint stability.
The knee has many moving parts, but they all work together to function like a hinge that lets the leg bend and straighten repeatedly. The design allows for a variety of positions and movements, such as walking, sitting, squatting, and kneeling.
The design is solid, but with all those parts, a variety of malfunctions can occur over the life of a knee. One common issue is called knee valgus….