What is wrong with the back of your knee pops and hurts? was told not a baker's cyst.

Knee popping: "popping" in the knee often suggests a partial tear in the cartilage (meniscus) in the knee, especially if there is buckling of the knee at times.. The pain usually is felt at the side of the joint, depending on which meniscus is injured, but you can sometimes have pain in the back of the knee. Other causes could include arthritis, acl injury, or collateral ligaments, or iliotibial band syndrome.