Osteoarthritis or Degenerative Joint Disease- the most common type of arthritis. Osteoarthritis is also known as “wear and tear arthritis” since the cartilage simply wears out. When cartilage wears away, bone rubs on bone causing severe pain and disability. The most frequent reason for osteoarthritis is genetic, since the durability of each individual’s cartilage is based on genetics. Trauma- can also lead to osteoarthritis. A bad fall or blow to the Knee can injure the joint. If the injury does not heal properly, extra force may be placed on the joint, which over time can cause the cartilage to wear away. Inflammatory Arthritis- swelling and heat (inflammation) of the joint lining causes a release of enzymes which soften and eventually destroy the cartilage. Rheumatoid arthritis, Lupus and Psoriatic arthritis are inflammatory in nature.