Coloured X-rays of the knee joint of a 59 year old male patient affected by chondrocalcinosis, or pseudogout, and osteoarthritis. In chondrocalcinosis, crystals of calcium pyrophosphate are deposited in soft tissues such as cartilage, the connective tissue found in joints. Affected joints are red, swollen and extremely tender. Treatments include the use of nonsteroidal anti-inflammatory drugs. If these fail a corticosteroid drug may be injected into the affected joints. Osteoarthritis is a degenerative joint disease that results from the breakdown of joint cartilage and the underlying bone, resulting in joint swelling, pain and a decreased range of motion. Treatment is with the surgical replacement of the joint.