Arthritis is the inflammation of the joints. Arthritis commonly affects older people, but can also…
What is arthritis?
Arthritis is an inflammation of the joints. It is caused by many disorders that affect the joints and their surrounding tissues. Arthritis affects people of all ages, but is more common in people over the age of 65.
Causes of arthritis depend on the specific type of arthritis and are detailed under the heading 'Types'.
Some general risk factors for developing arthritis include:
- Genetics - depending on the underlying cause, there are likely to be genes that increase the risk of arthritis, though exactly how these genes cause arthritis is not well understood;
- Age - cartilage becomes more brittle and the body less able to repair it as we age. Without functioning cartilage, the joints cannot absorb shock and are more easily damaged;
- Weight - joint damage is partly caused by the amount of stress placed on joints, which excess weight contributes to, particularly on the hips and knees;
- Previous injury - joint damage can cause irregularities in the normally smooth joint surface, which can aggravate surrounding tissue;
- Occupational hazards - jobs that place a high demand on the body, such as factory and construction jobs that require heavy lifting, increase your risk of developing arthritis;
- Sports - although a sports injury can result in arthritis, it is generally accepted that the benefits of general fitness and muscle strengthening outweigh the risks, and;
- Illness or infection - an infected joint can develop arthritis from the resulting inflammation.
There are many types of arthritis. Some of the more common ones are:
Rheumatoid arthritis (RA) is a chronic and generally progressive autoimmune disorder causing inflammation of the membranes lining the joints. It typically affects the smaller joints of the hand and feet.
Osteoarthritis (OA) is caused by the degeneration of cartilage, which loses its elasticity and becomes more easily damaged with age. It typically affects weight-bearing joints such as the hips and knees.
Juvenile arthritis is any type of arthritis occurring under the age of 16 years. As young people have not suffered from the same mechanical damage caused by ageing, most cases of arthritis in young people are likely due to autoimmune disorders, although the causes of many cases are unknown.
Infectious (septic) arthritis
Infectious arthritis is a joint infection due to bacteria, viruses or fungi. Usually the infection is established elsewhere in the body and reaches the joints by the bloodstream, or by getting directly into the joint through an open injury.
Polymyalgia rheumatica is a type of arthritis that causes inflammation in the larger joints and their surrounding tissues, such as the hips and shoulder joints. It causes muscle pain and stiffness in these areas. It is a common form of arthritis and mainly affects the elderly, but it is treatable. It is not to be confused with fibromyalgia, a different condition in which muscle pain and stiffness can occur anywhere in the body, not just the joints. Fibromyalgia does not cause inflammation. Rather, it is likely the result of overactive pain signals.
Psoriatic arthritis is an autoimmune disorder of the joints that can develop if you have psoriasis. While the exact cause is unknown, psoriatic arthritis is associated with HLA-B27, a protein on the surface of white blood cells that is linked to certain autoimmune disorders. If you have psoriatic arthritis, you should take note of what seems to trigger flare-ups, avoid those triggers and ensure you receive ongoing treatment as recommended by your doctor. In about 5% of cases, people develop a more severe form that results in bone deformities.
Gout is a type of arthritis caused by a build-up of uric acid (urate crystals) in the joints. Men are more likely to get gout, although the risk for women increases after menopause. Gout is one of the few causes of arthritis that can be effectively treated to prevent future damage.
Systemic lupus erythematous (SLE)
SLE, more commonly just referred to as lupus, is an autoimmune disorder. Its exact cause is unknown, but could be due to any or a combination of genetics, viruses, stress, or sunlight, among others. Flare-ups, which can vary in duration and severity, are periods when symptoms get worse. Most people with lupus can live a full life, if they stick to their treatment program. In some cases, however, complications can occur that can be life-threatening.
Bursitis is the inflammation of the bursae, which are small fluid-filled sacs between adjoining structures of joints, such as bones, muscles, and tendons. Technically bursitis is not a type of arthritis, because the bursae are outside the joints. It can be caused by injury or underlying conditions, such as rheumatoid arthritis.
Polymyositis is a disorder of connective tissue that causes inflammation, the cause of which is unknown. It affects women more than men and tends to occur between the ages of 50-70 years, but can affect people of all ages.
Other types of arthritis include:
Signs and symptoms
Symptoms vary according to the cause of arthritis. Common symptoms include:
Methods for diagnosis
Methods used to diagnose arthritis are:
Your doctor will likely look for signs of:
- Joint swelling, stiffness or tenderness;
- Redness or warmth around the joint due to inflammation;
- Restricted movement, and;
- Bumps or nodules.
Erythrocyte sedimentation rate (ESR)
ESR is a test used to indicate inflammation, but it does not diagnose a specific disorder. For this test a blood sample is taken and the rate at which red blood cells accumulate at the bottom of a test tube is measured. The higher the rate, the greater the degree of inflammation. Normal values will vary between laboratories according to different methods used. Your doctor will tell you what your results mean.
C-reactive protein (CRP)
Measuring CRP levels in the blood provides an indication of the degree of inflammation in the body. CRP is a general test that indicates that there is inflammation somewhere in the body, but does not localise the inflammation or identify its underlying cause. Your doctor may order this test to check if anti-inflammatory medicine is working, or during any flare-up periods of the inflammatory diseases.
Anti-cyclic citrullinated peptide (CCP) antibody
Anti-CCP antibodies are auto-antibodies, which means they are mistakenly directed against a person's healthy tissues instead of microorganisms. This test is used to confirm a diagnosis of rheumatoid arthritis.
Rheumatoid factor (RF)
RF is an auto-antibody directed against one of the body's antibodies, called immunoglobulin G (IgG). RF binds to IgG, forming immune complexes. When these complexes are deposited in the joints, they produce a reaction that causes inflammation. Up to 70% of people with rheumatoid arthritis have RF in their blood, but some people without rheumatoid arthritis can have it too.
Antinuclear antibody (ANA)
Normally the immune system produces antibodies to fight infection. ANAs attack your body's own cells. A positive result for ANAs does not necessarily mean you have an autoimmune disorder, because it can be caused by other conditions or certain medications. Some healthy people also have ANAs and this increases with age.
Human leucocyte antigen (HLA) B27 typing
HLAs are found on the surface of white blood cells. A particular type, HLA-B27, is associated with certain autoimmune disorders that may cause arthritis. In a healthy person, HLA-B27 will generally be absent, but its presence in your blood does not necessarily mean you have an autoimmune condition.
Other laboratory tests:
- Joint fluid tests;
- Creatinine and uric acid tests;
- Skin or muscle biopsy;
- Urine analysis, and;
- Serological tests for Lyme disease.
Other diagnostic tests:
Types of treatment
Treatment options your doctor will consider include:
These medications reduce pain and some are available without a prescription, such as paracetamol and low-dose codeine. Some that require a prescription include oxycodone, propoxyphene and higher-dose codeine.
Non-steroidal anti-inflammatory drugs (NSAIDs)
Disease modifying anti-rheumatic drugs (DMARDs)
DMARDs are a range of drugs that act on the immune system in different ways to prevent inflammation. They include drugs such as methotrexate, sulfasalazine and hydroxychloroquine. Their effects are not immediate and can take weeks to months to be noticed. Unlike NSAIDs, early intervention with DMARDs can slow down disease progression.
Biological therapies can work faster than DMARDs. They are drugs that act on the immune system and are sometimes used in conjunction with other medication if you have rheumatoid arthritis.
These are powerful anti-inflammatories that block the inflammatory pathway of the immune response. They can be taken orally or injected. Injection is usually only required in extreme cases of inflammation that only affect one or two joints.
Physiotherapy can help by improving mobility, flexibility and strength in arthritic joints.
When non-surgical methods fail, an orthopaedic surgeon may perform surgery to:
- Remove diseased or damaged tissue;
- Realign the joints;
- Release or repair tendons;
- Remove bone;
- Release trapped nerves;
- Fuse the ends of joint bones together to reduce joint motion and relieve pain, and;
- Replace a damaged joint with an artificial one.
Regular exercise can help improve flexibility, improve supporting-muscle strength and reduce fatigue.
Assistive devices, such as walkers, canes and raised toilet seats, are available to help protect the joints and improve your ability to perform daily tasks.
Hot and cold packs
Applying icepacks or heating pads may help reduce pain. However, speak to your doctor first, as this can make some types of arthritis worse.
Non-steroidal anti-inflammatory drugs (NSAIDs)
Side effects associated with long-term use of NSAIDs can be gastritis and ulcers in the digestive system. NSAIDs can also interact with other drugs. If you are taking NSAIDs for arthritis, your doctor or pharmacist will tell you what drugs you should not mix with them.
DMARDs can have a wide range of side effects depending on the agent used. Methotrexate can weaken the immune system, resulting in increased susceptibility to infection. It can also cause damage to the lungs and liver. Side effects and potential complications will be closely monitored by your treating doctor.
Biological therapies can result in the formation of anti-drug antibodies (ADAs), which can reduce the effectiveness of a treatment. Further research is needed to identify the optimal dosage required to reduce the problem of ADA formation. Biological therapies can also weaken the immune system, making it harder for the body to fight infections.
The outlook for arthritis varies, according to the underlying cause and response to treatment. Most forms of arthritis are chronic, with only a few able to be cured with treatment. Early diagnosis generally results in better treatment outcomes.
Ways you can help prevent the development of arthritis include: