Meniscus tear
The meniscus is a disk of cartilage that serves as a cushion between the bones at the knee joint. Knee injury resulting from overuse or sudden maneuvers characteristic of sports can cause this cartilage to rip. When this happens, you’ll often hear a pop sound followed by pain and swelling in the knee.
Meniscus tears [6] can result in serious knee pain and often require treatment. The treatment will depend on the extent of damage to the knee. Untreated meniscus tears can cause chronic knee pain and inflammation that persist for a long time.
Dislocation
Dislocation is a common cause of knee pain [7]. A dislocation occurs when a part of the body, such as the bone or kneecap, shifts from its normal position. Knee dislocation (or patellar dislocation) is often a result of the kneecaps sliding out of position. Sports accidents or other types of injuries often cause this to happen. You’ll usually experience pain and swelling in the area until it is treated. Most cases of dislocation are mild and can be fixed by noninvasive methods.