Unfortunately in anatomy and orthopedic surgery, the word "cartilage" is used to refer to many different structures that have very little similarity other than their native biochemical makeup. In the knee, the word cartilage is used both for the smooth gliding surfaces of the ends of the femur and tibia bones (articular cartilage) as well as the shock absorber pads located between the two bones and sitting on top of the tibia (meniscal cartilages).
Most people who have been told they have a torn cartilage usually have a tear of the meniscal (shock absorber) cartilage, but they might have torn or injured both types of cartilages. Usually if surgery has been done, this will involve an arthroscopic surgical procedure and the portion of the meniscal cartilage that was torn is trimmed out.
However if the meniscal cartilage was torn near its outside edge, then it can potentially be Repaired with sutures or other fixation materials. This type of tear is a much less common than the type that is trimmed out as mentioned in the previous paragraph.
Updated 1/17/09