Osteoarthritis is inflammation of the cartilage in joints which may develop with time to affect the underlying bone. It is a common condition and a major cause of joint pain and disabili- ty. It is recognised on x-ray by a narrowing of the space between the joints involved (due to carti- lage loss). See Fig 1.
Osteoarthritis (OA) was previously consid- ered to be a degenerative disease that was an inevitable consequence of ageing and trauma, however it is now viewed as a metabolically dynamic process that is increasingly amenable to treatment. The vast majority of osteoarthritic patients are managed in primary care and signifi- cant health gains are achievable, particu- larly in the elderly, by implementing
Exercise is an important therapy which can offer long- term benefits to affected individuals.
effective intervention strategies to reduce symptoms.
Clinical features of OA ● OA is characterised by joint pain which
is usually worse during or after use ● Pain at night or after rest is usually a sign of advanced disease ● Minimal joint stiffness, bony swelling and crepitus (crackling or grating in a joint) are characteristic ● The clinical impression is supported by plain x-ray findings – osteophytes (small bone growths), subchondral sclerosis (tis- sue hardening) and joint space narrowing – and a lack of biochemical evidence of a systemic inflammatory process
Fifty per cent of the general population with x-ray changes of OA knee do not have pain and 50% of people over 60 years of age who complain of knee pain have no definite radiographic evidence of OA. Therefore not all knee pain is OA and not all OA is painful.
Age Osteoarthritis is the most common joint
disorder and its prevalence increases with age. Radiological-based studies suggest that at the age of 70 years severe OA of the knee affects 30% of women and 20% of men.
Knee OA does occurs in young adults but infrequently. Significant injuries such as cruciate ligament injuries and meniscal tears may have an influence on subse- quent development of OA.
Most knee pain in the young reflects overuse rather than mechanical derangement and as such its relationship to OA is likely to be weak.
Progression Although it is likely that the joint disease will progress in OA, the rate of progression varies greatly between patients and also in individual patients at different times. Some joints appear to improve with time. Progression from mild or moderate OA to severe disease is uncommon and only a small proportion of patients undergo replacement surgery. Biochemical markers (serum and urine) may soon be used clin-