Advanced Surgery Getting to Know Your Knee The knee joint contains three bones: the thigh bone (femur), shin bone (tibia) and the knee cap (patella). The knee also contains two types of soft tissue: ligaments and cartilage. Pain usually results from an injury that damages these soft tissues. Knee pain can dramatically alter an individual's lifestyle. Normal knee function requires a smooth articular cartilage surface, an intact meniscus and stable connective ligaments. Ligaments are tissues that connect the thigh and shinbones and keep the joints stable. There are two types of cartilage that naturally occur in the knee—meniscus and articular cartilage: Articular cartilage: Articular cartilage is a durable tissue that covers the end of the thigh and shinbones. Articular cartilage is often damaged by sports, traumatic injuries, work injuries or daily wear and tear. Articular cartilage damage often occurs in conjunction with damage to another area of the knee—for example, with injury to the anterior cruciate ligament (ACL) or the meniscus. Articular cartilage does not have the natural ability to heal itself, but there are many treatment options to repair the damaged cartilage. Meniscus: The second type of cartilage in the knee is meniscal cartilage. The knee has two of these crescent-shaped wedges of cartilage, one on the outside (lateral meniscus) and one on the inside (medial meniscus). The meniscus acts as a cushion between the bones and as a stabilizing tissue for the knee.