Joint pain (arthralgia)

• Common causes of joint pain
• When to apprach your healthcare professional
• What will the healthcare professional do?
• Tests of joint pain
• How is joint pain treated?
• Prevention of joint pain

Common causes of joint pain

Joint pain (arthralgia) is an extremely common symptom which most people will experience at some point in their lives. Joint pain has many different causes, ranging from local injury to the joint to whole-body illnesses which include joint pain as one part of the disease.
Joint pain can be caused by a number of different mechanisms. Joint pain may be caused by damage to a structure within the joint itself (such as the joint surface) or by damage to a structure near the joint, such as a tendon. Joint pain may be due to local damage within the joint, or may be just one part of a systemic (whole-body) disease process. One of the most important distinctions to make is whether joint pain is caused by inflammation of the joint (an immune response involving swelling, redness and warmth) or whether there is joint pain without inflammation.
Inflammatory joint disorders are characterised by:

• Swelling, redness, warmth and pain;
• Systemic (whole-body) symptoms, such as fatigue, fever or weight loss;
• Marked morning stiffness, or stiffness that worsens with long periods of rest and inactivity, and is improved with movement or anti-inflammatory drugs. Common inflammatory joint disorders include:
• Rheumatoid arthritis;
• Seronegative spondyloarthropathies, including ankylosing spondylitis and psoriatic arthritis;
• Infectious arthritis: bacterial (septic arthritis), viral (e.g. Ross River Virus) or other;
• Reactive (post-infectious) arthritis, e.g. reactive arthritis;
• Inflammatory osteoarthritis;
• Crystal arthropathies: e.g. gout or pseudogout;
• Systemic rheumatic illnesses causing arthritis: e.g. systemic lupus erythematosus, Behcet’s disease;
• Other systemic illnesses, e.g. sarcoidosis, acromegaly.

Non-inflammatory joint disorders are characterised by:

• Pain without swelling or warmth;
• Absence of systemic symptoms such as fever or weight loss;
• Minimal morning stiffness which is intermittent, lasts less than 60 minutes; and
• Stiffness which is made worse, not improved, by activity. Common non-inflammatory joint disorders include:
• Trauma, e.g. tears to muscles, tendons or cartilage around the joint; or Osteoarthritis. Some people may also experience joint pain as a symptom of depression.

When to approach your healthcare professional

Any unexplained joint pain which is causing you trouble should be investigated. In particular, there are certain ‘warning signs’ which need quick review by a healthcare professional. These include:

• Joint pain with fever, not caused by the flu;
• Involuntary weight loss; or
• Unexplained joint pain which lasts longer than 3 days, or is severe.

What will the healthcare professional do?

Your healthcare professional will try to determine the likely cause of your joint pain by asking you a number of questions.

• What does the pain feel like? Is it deep, on the surface, in one spot or all over?
• Which joints are painful? Some types of arthritis have particular patterns of joint involvement, which may help in making a diagnosis.
• Are there any associated joint symptoms? For example, does the joint ever feel like it is ‘giving way’ under you, or ‘sticking’?
• Have you ever injured or had surgery to the joint?
• How long has the pain been present for? Pain which develops quickly is likely to be due to a different cause than pain which has been present for weeks.
• Do you feel generally well, or is the joint pain associated with tiredness, weight loss or fever?
• Has anyone else in your family had problems with joints? Family members with gout, rheumatoid arthritis, or other types of arthritis such as psoriatic arthritis are particularly important, as these conditions may be inherited.
• How is the joint pain affecting your life and your ability to manage daily tasks?

Your healthcare professional will then need to examine the joint(s) which are involved. This usually involves a careful inspection of the joint to look for swelling, redness, scars or deformity, followed by assessment of the range of movement that is possible. Special manoeuvres may also be needed to identify particular causes of joint pain.

Tests for joint pain

If the likely cause of your joint pain has not been established after asking you questions and examining the joint, your healthcare professional may wish to arrange some tests.

Blood tests

• Full blood picture: a raised white cell count may indicate inflammation or infection;
• ESR or CRP: raised levels of these tests may suggest an inflammatory cause for the joint pain;
• Uric acid: gouty arthritis is caused by excess levels of uric acid in the blood. In an acute attack, however, the level of uric acid in the blood is not always raised.
• Viral serology: if your health professional suspects that your arthritis may be caused by a virus such as Epstein Barr virus, parvovirus B19, hepatitis B or hepatitis C, he or she may order tests to look for these viruses in the blood;
• Special blood tests may also be done for some immune proteins such as rheumatoid factor or antinuclear antibodies (ANA). Presence of these proteins in the blood may be associated with auto-immune diseases such as rheumatoid arthritis or systemic lupus erythematosus. However, they may also be present in normal people.

Joint fluid analysis

This involves using a needle to take a sample of the fluid within a swollen joint. The fluid can be examined to look for presence of inflammation, bacteria, or crystals associated with diseases such as gout. Your health professional may order joint fluid analysis if he or she particularly suspects that you have a bacterial infection or crystals (gout or pseudogout) in the joint.

Imaging

Plain x-rays can be useful in the diagnosis of some joint disorders such as trauma or osteoarthritis. In inflammatory joint disorders, it may take much longer for the joint changes to be seen on plain x-ray. In these cases your health professional may arrange for you to have an ultrasound or MRI scan of the joint.

How is joint pain treated?

The treatment for your joint pain will depend on the cause. The best sort of analgesia (pain relief) for your joint pain is also partially dependent on the cause – inflammatory joint pain is likely to respond well to corticosteroids or non-steroidal anti-inflammatory drugs such as ibuprofen, whereas non-inflammatory joint pain is better managed with paracetamol. Other techniques to manage joint pain include physiotherapy.

Prevention of joint pain

It is not possible to prevent the development of many diseases which cause joint pain, including rheumatoid arthritis and other auto-immune causes of joint pain. Osteoarthritis is a common cause of joint pain which is thought to result from ‘wear and tear’ on a joint over a number of years. Some simple lifestyle changes can help reduce this wear and tear, including weight loss, wearing comfortable shoes, or learning safe techniques for lifting, and these may reduce the likelihood of developing osteoarthritis later in life.
 

References

1. Braunwald, Fauci, Kasper, Hauser, Longo, Jameson. Harrison’s Principles of Internal Medicine. 16th Edition. McGraw-Hill. 2005.
2. Pinals, RS. ‘Evaluation of the adult with polyarticular pain’ [online]. UpToDate.com. 2006. Available at URL: http://www.uptodate.com (last accessed: 2/9/06)
3. Solomon L, Warwick DJ, Nayagam S. Apley’s Concise System of Orthopaedics and Fractures. London, Hodder Headline Group, 2005.