Our joints are made up of a ball and socket. Covering the ball, which is the head or end of the bone that rests in the socket, is cartilage. Cartilage is a slippery tissue that allows bones to glide smoothly over each other as we move and helps absorb the shock placed on the joints with movement. If cartilage wears away, that cushion between the joints is lost, causing an issue known as bone on bone. Knee joints are especially susceptible to this kind of wear and tear. The cause of this issue is usually osteoarthritis, which is a degenerative form of arthritis that affects the joints.
Bone on bone knee pain occurs as the bones rub together, causing friction and interfering with the knee joint’s ability to move freely. This friction can wear down the surface of the bones which can alter the bone’s shape and cause bone spurs to form. Bone on bone knee arthritis can also cause tiny pieces of bone and cartilage to break away and float within the joint space, causing further damage and pain.
Knee bone on bone symptoms begin gradually as the cartilage in the knee wears down. Along with bone on bone knee pain, which can be quite severe, other symptoms often include:
Stiffness, often worse after rest or sitting
Grating or crunching sensation and sound when moving the knee
Decreased flexibility and range of motion
Inability to bend the knee
Bone spurs are also a sign of bone on bone in the knee. Bone spurs form on the edges of the bones as our body’s natural response to degenerative changes as it rebuilds more bone to make up for the loss. This extra bone results in bony growths that can cause pain and can sometimes be felt on the outside of the knee.