Your knee is the largest joint in your body, and when it’s healthy it moves easily. The healthy knee lets us walk, turn and squat without any pain. The network of bones, muscles, ligaments, tendons, cartilage and other soft tissues in your knee all work together to provide your body with both stability and mobility.

Knee pain can be a result of natural aging and breakdown of knee components. Pain can also come from overuse during high-impact activities and sports, or from acute injuries due to falls and missed footing.

Synovium

Soft tissue known as synovial membrane cushions your joints and produces synovial fluid (joint fluid), which lubricates knee motion. In the case of injury, the synovium can become inflamed, and secrete excess synovial fluid (a protective response). Over time, this inflammation can destroy some of your cartilage and even bone.

Cartilage

Cartilage comes in different forms, but they all function to absorb shock and protect your bones. There are two types of cartilage in your knee: articular cartilage and meniscal cartilage.

When this cartilage is worn away through injury or overuse pain can develop.

Meniscal cartilage is thick and rubbery and acts like a shock absorber to help the knee withstand applied forces.

Ligaments

Ligaments connect bones to each other. They provide strength and stability to the knee joint from front to back, side to side, and from rotation. Each of the major ligaments are vulnerable to damage from different types of motion.

Tendons

Tendons connect muscle to bone. Overuse can cause tendonitis, which produces local pain and tenderness. Tendons can also rupture.