Injury to one of the two crescent-shaped cartilage pads between the two joints formed by the femur (the thigh bone) and the tibia (the shin bone) is Meniscal injury. A partial or total tear of a meniscus may occur when a person quickly twists or rotates the upper leg while the foot stays still (for example, when dribbling a basketball around an opponent or turning to hit a tennis ball). After any injury the knee may click, lock, or feel weak. Symptoms of meniscal injury may disappear on their own but frequently, symptoms persist or return and require treatment.