Osteoarthritis
Reproduced from Issue 112 of Arthritis Today
There's no cure, but the effects of this common condition can be minimised, says Dr Gill Hosie, a Glasgow GP and President of the Primary Care Rheumatology Group.
Osteoarthritis(OA) is the most common joint disorder and affects 10-25% of all people aged over 65. OA usually occurs at the knee, hip, spine and in the hands, especially at the base of the thumb and in the fingers.
OA is not really a disease nor even a single condition. Rather it is the end result of a number of different episodes of damage to the joint over a period of time, together with the body's own repair processes.
These repair processes include reshaping of the joint, so that a bony outgrowth builds up at the edges of the joint. This results initially in a joint which looks different to normal but which nevertheless functions well and without pain. Eventually the joint may become painful with a variable degree of disability.
Risk factors for OA
Risk factors for OA can be divided into avoidable and unavoidable.
Unavoidable risk factors include genetic inheritance. If other close members of your family, such as brothers and sisters, have had surgery for OA there is a three to five-fold higher risk of you developing OA than in the general population. Heberden's nodes which are little bony nodules growing around the furthest joints of the fingers or thumbs indicate a strong genetic tendency to develop knee OA. Knee OA is more common in women while OA of the hip is equally common in men and women, and all OA is more common in the older age groups.
Avoidable risk factors for OA include being overweight, injury to the joint and repeated minor pressures on the joint such as those sustained during some sports, or in the course of certain jobs, for example, those involving repeated kneeling or lifting. Hip disease in childhood is also a risk factor for hip OA. Obviously it is not possible to alter your genetic background. If you do have genetic risk factors, however, it is sensible to avoid adding to the risk of developing OA by maintaining a healthy weight, taking sensible exercise and avoiding injuries and stresses to the joints caused by sport or work as much as possible.
Management of OA
There is no specific treatment for OA. Management involves providing education and support, assessing the degree of disability and how it affects the way people cope with everyday tasks. It should also take account of avoidable risk factors and assess the impact of other diseases present and drugs being taken, and of course, patient preference.
Information and education
Everyone should have access to information about OA. This can be in various forms such as group classes perhaps run by a nurse or physiotherapist, individual back-up by a practice nurse, literature and leaflets provided by either hospital or primary care or the excellent series of leaflets provided by the ARC.
Everyone is different, and while joining a group class or a self-management group may appeal to some patients, others will prefer to tackle the problem by themselves. The important point is that the facilities are available for each person to make his or her own choice.
Exercise
Exercise is an important component of the management of OA. There are two main forms of exercise:
aerobic exercise where the individual raises his or her heartbeat, sweats and becomes breathless and local strengthening exercise where individual muscles are made to work to build up their strength
- Aerobic exercise has a definite benefit in OA and helps with weight control and often improves sleep pattern. It also seems to increase general well being and helps some of the other medical conditions that those with OA often have, such as diabetes and hypertension.
- Local strengthening exercise is particularly useful in OA of the knee where the large muscle on the front of the thigh, the quadriceps muscle, is strengthened by a specific exercise programme. This can be done in a class or quite easily at home and reduces pain and disability and improves balance and stability.
Both forms of exercise should be used regularly and should be built up gradually until the individual reaches a comfortable level. It is often difficult to keep up enthusiasm for exercise but it is important that this is continued for life if at all possible.
Weight loss
Being overweight makes OA in the knee or hip worse and increases disability and pain. Obesity is also a risk factor leading to a worsening of OA. Slow steady weight loss is best achieved by a gradual change in eating habits combined with exercise.
Other options
If you plan to undertake a specific activity such as a long walk
or a spell of gardening or shopping, it is sensible to have frequent
breaks so that the task can be finished but with less mechanical
stress on your affected joints. If you have OA of hip or knee you
can reduce pain by using appropriate footwear. A good training shoe
has all the suitable features, which include a thick sole to absorb
impact, no raised heel, a broad forefoot and soft uppers. If you
do not like the appearance of trainers you can usually find some
fashion shoes with similar qualities.
Drug therapy for OA
The drug of first choice is paracetamol which can be taken in a dose of up to eight 500mg tablets per day. This is often surprisingly effective and can be taken by most people with no problems. It is also safe in the long term provided the maximum daily dose is not exceeded. It is best to take paracetamol before doing something which brings on pain in the joint.
If paracetamol does not control the pain your doctor may suggest that you buy a cream or ointment to rub on the joint. Other options are different or stronger painkillers, or anti-inflammatory drugs such as ibuprofen. Anti-inflammatory drugs may be prescribed by your doctor and may be helpful especially where there is an acute flare of symptoms. The down side of these drugs, however, is their potential to cause side effects especially stomach problems and to interact with other drugs.
Other options
Other options include injection of steroid into the joint or, in the case of the knee, injection of an artificial synovial fluid. If symptoms progress and pain and disability worsen, an operation to replace the joint may give considerable relief. These joint replacement operations are extremely successful for the great majority of patients, are increasingly being performed and offer an excellent option for pain relief.
Dietary supplements
Glucosamine sulphate is a food supplement which can be bought from health food shops, but is not available on NHS prescription. It is an expensive, but some patients appear to find it helpful. Glucosamine seems to be safe with no undesired side effects and has been available in continental Europe and the USA for several years.
The future
Work is currently underway looking at a number of drugs, which may help to protect cartilage and prevent the damage which leads to the development of OA. Meantime we should be trying to minimise the long-term problem by encouraging exercise and weight control in society at large.
