There are over a hundred types of arthritis but the five common types are:-
Wear and tear or mainly degenerative (such as osteoarthritis). This is when the cartilage or the “shock absorber” inside the joint gradually deteriorates over a period of time and the bones around it thicken and grow stiff, with little inflammation. (Osteoarthritis of knees and cervical spondylosis are common examples.)
Inflammatory (such as rheumatoid arthritis). In rheumatoid arthritis, the body’s defense or immune system goes wrong and body’s “soldiers” instead of attacking invading bacteria attack the joints producing arthritis. Pain and stiffness of joints of extremities may lead to disability and if left untreated for a long time, deformities of hands and feet can follow.
Body chemistry defects (such as gout). This sort of inflammation usually affects one or two joints. In gout, the body has too much uric acid in blood and these injurious crystals get deposited in joints producing very intense pain.
Infection, when bacteria are actually present in the joints (causing septic arthritis) or when arthritic symptoms occur sometime after the infection (as in the case of rheumatic fever and reactive arthritis). In this second type, it seems as though the infection which may be anything from a sore throat to dysentery can indirectly trigger off changes in the joints though no bacteria are actually transferred there through the blood stream.
Soft tissue rheumatism, where tissues around the joint are affected by injuries, sprains, strains etc and as a result degenerate or become inflamed. Examples are fibrositis, tennis elbow, shoulder peri-arthritis and similar aches and pains.