Osteoarthritis (OA) is a degenerative joint disease, it normally occurs when the cartilage becomes damaged due to aging or due to injury or illness. When the cartilage is damaged, it can become rough along the surface creating pain when the joint is used. When the cartilage deteriorates, the bones can rub together which can also be very painful. Osteoarthritis causes pain, swelling and fewer motions in joints. It can occur in any bone joint but prominently it occurs in hip, spine, knees and hands. It is a commonly occurring kind of arthritis.

Imaging modalities that are used are X-ray, CT, MRI and ultrasound. The initial evaluation is done by joint x-ray. MRI of the knee can directly visualize articular cartilage and cover the whole joint three-dimensionally so the cartilage and its defects can be visualized directly, regardless of their location. Scintigraphy provides the metabolic information about bone and soft tissue structures. CT is used to visualize the cortical bone and soft-tissue calcifications. CT has a high sensitivity in the detection of intra-articular loose bony fragments.