Osteoarthritis

Osteoarthritis is a condition in which the joints of the body become damaged, stop moving freely, and become painful. Osteoarthritis results from a combination of the breakdown of the joint and the body’s attempted repair processes. Cartilage (the tissue that coats the end of bones) roughens and becomes thin, the underlying bone thickens and grows into the joint forming bony spurs (osteophytes), and the gap between the bones narrows. The inner layer of the joint capsule (synovium) may thicken and make excess fluid, causing the joint to swell, while the capsule and ligaments around the joint thicken and contract. In severe osteoarthritis, the loss of cartilage can result in bones rubbing against each other and wearing away.

Pain is the main symptom of osteoarthritis and can have a devastating impact on people’s lives, preventing sleep and causing fatigue. Depending on the joints involved and severity, the lack of mobility caused by osteoarthritis can impact on many areas of life, preventing people from fully living their family, social and intimate lives, and reducing their ability to work. Self-confidence, self-esteem, wellbeing and quality of life can all be significantly reduced.

The causes of osteoarthritis are not yet fully understood. However, a range of factors which increase the risk of osteoarthritis are known, and it is often a combination of these that leads to its development. Osteoarthritis can be caused by damage to the joints, either through repeated excessive loading and stress of a joint over time (for example, the knee joint in an obese person) or by injury (such as a break or dislocation of a finger joint). Genetic factors make some people more likely to develop osteoarthritis. Risk factors vary depending on the joint involved and different factors may affect the initial development of osteoarthritis in a joint, and the extent to which a joint is affected over time. The main risk factors for osteoarthritis include:

• Age: Osteoarthritis is more common in people from their 40s and increases with age.

• Gender: Osteoarthritis is more common in women than in men for most joints.

• Obesity: Being overweight increases loading on the joints and the risk of osteoarthritis, especially in the knee.

• Bone density: High bone density is a risk factor for the development of knee, hand and hip osteoarthritis; low bone density is linked to rapid progression of knee and hip osteoarthritis.

• Joint injury or disease: Injury to a joint, joint surgery or other types of joint disease (including rheumatoid arthritis or gout) may lead to osteoarthritis.

• Occupation: Physically demanding work can increase the risk of osteoarthritis in some joints.

• Joint abnormalities: Osteoarthritis can result from abnormal development of joints.

• Genetic factors: Genetic factors are a key risk factor for osteoarthritis of the hands, and play a smaller role in osteoarthritis of the hip and knee. The genes involved are not fully known.

Osteoarthritis can affect any joint in the body, but the most commonly affected joints are the knee and hip as well as joints within foot, ankle, hand and wrist (see figure 3). Within the hand, the joints at the base of the thumb and the ends of the fingers are most often affected. It is common to have osteoarthritis in more than one region of the body.

Joints within the spine (back and neck) are also affected by osteoarthritis, particularly the joints of the lower back. Osteoarthritis within spinal joints is challenging to diagnose as there is a relatively weak association between back pain (which is very common in adults) and changes to the joints of the spine which are visible on x-ray. Therefore, osteoarthritis of the spine is not considered in this report.

There are a range of treatments for osteoarthritis; an important aspect of treatment is to agree and then regularly review a management plan which people can use to help them self-manage their osteoarthritis. Exercise, of an appropriate type and level, should be included as a core treatment. Other aspects of treatment which can be included depending on the joints involved are weight loss and maintenance of a healthy weight, lifestyle change to avoid stress on the joints (such as pacing the amount of activity undertaken), painkilling medication, use of joint supports and assistive devices. For people with severe arthritis, joint replacement can be necessary and very successful in reducing pain and increasing mobility.