Osteoarthritis is the most common form of arthritis in the world. It affects huge numbers of people and is often accepted as an inevitable part of ageing. As industrialized populations become older and live longer, the effects of osteoarthritis (OA) will become more marked.
A slowly progressive joint disease, it can lead to local joint destruction and disability.
It is recognised as a group of conditions which present with similar features in the person and on xrays, whatever the underlying cause may be, which may not be clear. The end result is “joint failure”.
Definition of osteoarthritis
(Osteo - bone, arthritis - joint inflammation)
There is no simple definition of OA. One definition was proposed by a workshop held in 1995 and is interpreted by the author as:
“Osteoarthritic diseases are the result of both mechanical (physical stresses) and biological events which interfere with the balance of building up and breaking down in the joint cartilage and the underlying bone.
OA involves all the tissues of our joints although it may be caused by many factors. OA exhibits multiple changes which result in softening, cracking and ulceration of joint cartilage, hardening of the bone beneath the cartilage and bony outgrowths.
These changes may go unnoticed by the person but when they become evident the symptoms consist of joint pain, tenderness, limitation of movement, cracking and crunching, perhaps swelling and inflammation.
Unlike arthritic diseases such as rheumatoid arthritis there are no systemic effects - ie effects on the whole person such as feeling unwell or loss of weight.”
The American College of Rheumatology has classified OA into primary (OA appears without obvious cause) and secondary (OA caused by something known).
- Localized - ie of either hands, feet, knees, hips - one site affected
- Generalized - three or more of the above joint groups affected
- Post-traumatic - after an accident or injury, especially if it affected the joint directly
- Congenital/developmental diseases which cause joint abnormality
- Localized problems - joint abnormality such as congenital dislocation of the hip
- Generalized problems - various metabolic diseases
- Other bone and joint disorders - rheumatoid arthritis (RA), Paget’s disease, avascular necrosis (where part of the joint dies from cutoff of the blood supply)
- Endocrine (hormonal) diseases
- Joint disease due to nerve problems.