Osteoarthritis, Causes, Signs and Symptoms, Diagnosis and Treatment.

Osteoarthritis (OA) is a type of joint disease that results from breakdown of joint cartilage and underlying bone.[5] The most common symptoms are joint pain and stiffness.[1] Usually the symptoms progress slowly over years.[1] Initially they may occur only after exercise but can become constant over time.[1] Other symptoms may include joint swelling, decreased range of motion, and, when the back is affected, weakness or numbness of the arms and legs.[1] The most commonly involved joints are the two near the ends of the fingers and the joint at the base of the thumbs; the knee and hip joints; and the joints of the neck and lower back.[1] Joints on one side of the body are often more affected than those on the other.[1] The symptoms can interfere with work and normal daily activities.[1] Unlike some other types of arthritis, only the joints, not internal organs, are affected.[1]

Causes include previous joint injury, abnormal joint or limb development, and inherited factors.[1][2] Risk is greater in those who are overweight, have legs of different lengths, or have jobs that result in high levels of joint stress.[1][2][6] Osteoarthritis is believed to be caused by mechanical stress on the joint and low grade inflammatory processes.[7] It develops as cartilage is lost and the underlying bone becomes affected.[1] As pain may make it difficult to exercise, muscle loss may occur.[2][8] Diagnosis is typically based on signs and symptoms, with medical imaging and other tests used to support or rule out other problems.[1] In contrast to rheumatoid arthritis, in osteoarthritis the joints do not become hot or red.[1]