The meniscus is soft, resilient cartilage in your knee joint between your thigh bone (femur) and shin bone (tibia). It creates a cushion to absorb shock and to prevent bone rubbing on bone. If you twist too quickly or radically at your knee joint when your knee is bearing weight, you can tear the meniscus. It is a common sports injury when athletes run, jump, juke, or pivot. But, really, it can happen even while you are moving about in your kitchen or at the office.