• Cartilage defect. A cartilage defect can occur acutely when standing, turning, or pivoting during sport or as a result of trauma. This is usually followed by swelling of the knee and is aggravated by walking, standing, rising from a chair, or going up or down stairs.  Sometimes a cartilage fragment can’t come loose from the adjacent bone, which is most recognizable by a longer period of slight pain in the knee aggravated by an acute moment with locking and mechanical symptoms

A cartilage defect is characterized by:

• Pain and tenderness. A cartilage defect causes diffuse pain in the whole knee, sometimes more specific in the damaged compartment, or pain more deeply located in the back of the knee
• Locking. If a loose piece of cartilage gets stuck between the moving parts of the knee, the knee can be locked. This is a very acute phenomenon that occurs and disappears spontaneously.  Sometimes a loose piece can be felt floating around
• Swelling. This occurs because damage to the articulating surface causes the knee to swell, which usually is related to the amount of loading