Where is the pain?

What say you on the issue below?

Distinguishing the joint pain that is characteristic of arthritis.

THERE are many causes of joint pain. In and around the joint, there are numerous structures that can give rise to pain – from the ligaments or muscle outside the joint, or from disease within the joint capsule.

“Rheumatism” is derived from the Greek word, “rheumatikos”, from “rheuma”, a flow. It is generally used to refer to the many pathological conditions, characterised by discomfort and disability, which can occur in the muscles, tendons, joints, bones or nerves.

“Arthritis” literally means joint inflammation. “Arth” refers to the joints, and “itis” refers to inflammation. Arthritis is not a single disease, and not all arthritis is inflammatory.

Although osteoarthritis can affect almost any joint, it most often affects the hands, knees and spine.

Typically, arthritis is used to refer to diseases that cause problems within the joint capsule, and rheumatism for conditions that affect structures outside the joint capsule.

Usually, rheumatism is regarded as less serious, and in many cases, can be self-limiting. Some examples of rheumatism would be tennis elbow or plantar fasciitis (a type of heel pain).

In contrast, if arthritis is left untreated, it may lead to joint deformity and disability. There are more than 100 different types of arthritis affecting people of all ages. However, arthritis and rheumatism have one thing in common – all their sufferers feel pain.

Is it arthritis?

When you feel pain around your joints, how do you know whether you have serious arthritis?

If joint pain persists, you need to see a doctor. When you go to the doctor, he/she will ask you questions about your joint pain. This is to try to work out exactly where your pain is coming from, and if it is coming from the joint, to differentiate whether your pain is mechanical or inflammatory in nature, as discussed in the previous article.

The doctor would then examine the affected joint(s) and perhaps do some blood tests or x-rays if required, before coming to a diagnosis.

Osteoarthritis

The most common arthritis is osteoarthritis (OA). Although uncommon in the younger population, it becomes very common with advancing age. X-ray evidence of OA occurs in the majority of people by 65 years of age, and in about 80% of those aged over 75 years.

However, it is well-known that x-ray changes of OA do not correlate with the symptoms of pain. For example, symptomatic knee OA affects only about 12% of people over the age of 65.

The underlying pathology is that there is a gradual loss of cartilage from the joints, with associated changes in the underlying bone. Although OA can affect almost any joint, it most often affects the hands, knees and spine.

Patients commonly present with mechanical joint pain, which is worse on activity and relieved at rest. Morning stiffness, if present, is not prolonged and lasts under 30 minutes.

Movement of a joint affected by OA may cause a crackling or grating sensation called crepitus. This sensation likely occurs because of roughening of the normally smooth surfaces inside the joint.

Joint swelling can occur, either as a result of fluid accumulation, or due to the growth of bony outgrowths called osteophytes or bone spurs.

Rheumatoid arthritis

The most common, serious, chronic, inflammatory arthritis is rheumatoid arthritis (RA). The prevalence of RA worldwide is approximately 1% to 2% of the population.

RA may start insidiously with fatigue, muscle pain or a low-grade fever. Eventually, the joints will get involved, with pain, swelling and stiffness and they can feel warm to the touch.

As it is an inflammatory condition, the joint stiffness is typically most troublesome in the morning (early morning stiffness) and after inactivity. This early morning stiffness is prolonged, usually lasting more than an hour.

In the early stages, RA typically affects small joints, especially the joints at the base (knuckles) and the middle of the fingers, wrist joints, and the joints at the base of the toes. It may also begin in a single, large joint, such as the knee or shoulder, or it may come and go and move from one joint to another.

As the condition progresses, the joints on both sides of the body will be involved and are permanently affected.

RA is an autoimmune disease, which means that the body’s immune system mistakenly attacks its own tissue. There is increased production of abnormal antibodies that can cause inflammation, and thus swelling, in the joints and other organs.

The diagnosis is made from assessing joint symptoms, physical examination, blood tests, and sometimes x-rays or joint ultrasound scans.

One of the blood tests most frequently done to detect “arthritis” is the rheumatoid factor (RF). RF is an autoantibody against one of the immunoglobulins (a type of protein) in the body. However, only 70% of patients with RA have the RF antibody, so it is still possible for someone to have RA even with a negative RF test.

Conversely, the RF can be positive in patients with other conditions, such as chronic infections, not just RA. Thus, the final decision on whether or not you have RA lies with the doctor/rheumatologist after a thorough evaluation.

Treatment options

After diagnosis, many people would need some form of treatment for their arthritic pain. Treatments can be non-pharmacological (ie no medicine is given) or pharmacological (medicine is prescribed). The following is a (very) brief summary of the treatment options.

Exercise

Exercise is an example of a non-pharmacological treatment for arthritis. The cardiovascular benefits of exercise are well known. But patients with arthritis can also benefit.

Many patients with arthritis do not exercise because of joint pain and stiffness. Unfortunately, prolonged lack of usage of a joint can lead to muscle wasting and weakness, causing more pain and stiffness when the joint is moved. It can also cause the joint to feel “unstable”.

This muscle wasting can occur very rapidly; it takes only seven days of bed rest to reduce muscle bulk by up to 30%.

Generally, patients with active arthritis and swollen joints should not undergo vigorous exercise, but once the arthritis is under control, both strengthening and endurance exercises can be started. Strengthening exercises help to improve joint stability and thus reduce pain. Endurance exercises improve cardiovascular fitness and help feelings of fatigue.

For patients with arthritis, low-impact exercises such as swimming or biking are recommended. If you have not exercised before, please talk to your doctor or physiotherapist first.

In general, exercise should start at a low intensity and for a short time. It is normal to feel some joint or muscle soreness after exercising, although soreness should not last more than two hours. If pain or fatigue lasts into the next day, the exercise was probably too long or too vigorous.

Medications to relieve pain

Simple painkillers such as paracetamol are readily available and can relieve many kinds of pain. When the pain persists, stronger painkillers such as non-steroidal anti-inflammatory drugs (NSAIDs) or COX-2 inhibitors (COXIBS) can be used.

As with all medication, each type of painkiller has its individual benefits and risks, which should be considered before being taken. If you are requiring regular medications to relieve your pain, it is best to discuss your pain and/or other symptoms with your doctor further.

Medications to treat arthritis

Ultimately, arthritis should be treated with medications that correct the underlying pathology. This would mean that different types of arthritis would have different treatments.

For example, in OA, treatment would be directed at trying to improve the cartilage. In RA, the underlying inflammation is treated with medicines called disease-modifying anti-rheumatic drugs (DMARDs) that suppress immune system overactivity.

Prolonged joint inflammation will lead to joint damage. It is therefore very important that patients with RA are treated early with DMARDs to suppress inflammation and consequently preserve joint structure, maintain joint function and reduce disability.

The treatment of RA has been revolutionised by the introduction of a new class of DMARDs called biologic DMARDs that are much more effective at suppressing inflammation compared to the traditional DMARDs. With these new drugs, remission (the absence of any swollen or tender joints) is now possible in RA.

To conclude, not all joint pain is due to arthritis, not all the arthritides have the same underlying pathology, so not all arthritis treatments can be the same; one size definitely does not fit all!

Next week – we’re going to bust the myths surrounding arthritis!

References:

1. Arden N, Nevitt MC. Osteoarthritis: epidemiology. Best Pract Res Clin Rheumatol. 2006; 20: 3-25

2. http://www.patient.co.uk/doctor/Osteoarthritis.htm (accessed 25 July 2011)

3. http://www.hopkins-arthritis.org/arthritis-info/rheumatoid-arthritis/rheum_clin_pres.html#epid (accessed 25 July 2011)

4. Adams S, Forrest S. ABC of Intensive Care: Other Supportive Care. BMJ 1999; 319: 175-8

5. http://www.uptodate.com/contents/patient-information-arthritis-and-exercise?source=search_result&selectedTitle=1~10 (accessed 25 July 2011)

This article is a collaborative effort by Dr Yeap Swan Sim together with MSD and is supported by the Arthritis Foundation of Malaysia. This article is for educational purposes only.