Polymyalgia Rheumatica
Polymyalgia rheumatica (PMR) is an inflammatory condition that causes pain and stiffness in the shoulders and the hips. The pain and stiffness is usually much worse in the mornings and fatigue is also quite common.
The cause of PMR is not well understood. Some theories propose that it might be caused by an external factor like a virus that stimulates the immune system to behave in an undesirable way.
In about half of people who get PMR, it’s a self-limited disease, which means it goes away by itself after a few months to a couple of years. In others, PMR can be more chronic (long-term) and can linger for much longer.
Similarities to Other Diseases
PMR is sometimes mistaken for another type of inflammatory arthritis called rheumatoid arthritis(RA). RA can also start in the joints of the shoulders, causing pain and stiffness. RA isn’t like PMR because in RA other joints usually become affected over time, and because RA is a chronic (long-term) condition known to be an autoimmune disease. Polymyalgia rheumatica only affects the joints surrounding the shoulders and the hips.
A variety of other conditions can sometimes act like PMR, but are not related to any type of arthritis at all. These include some types of cancer, heart infections, and thyroid conditions.
Who Gets PMR
People who develop PMR are older than 50. Women are more likely to get PMR than men.
PMR can also occur with another condition called Giant Cell Arteritis, which is commonly known as temporal arteritis. About 15 out of every 100 people with PMR also have temporal arteritis.
Understanding PMR
Symptoms
Intense Pain and Stiffness
Polymyalgia rheumatica (PMR) tends to come on suddenly, sometimes overnight. People with the disease often develop an intense pain and stiffness in the shoulders and hips over a few days.
The stiffness tends to be worse after a period of rest and in the morning, which can make it difficult for people with PMR to get out of bed and get dressed.
In some people with PMR, the stiffness gets better once the joints have had a chance to get “worked out”. In others, the pain and stiffness can last all day. This can make sleeping uncomfortable, and most people who develop PMR suffer from significant fatigue.
Temporal Arteritis
About 15 of every 100 people with PMR that also have temporal arteritis (Giant Cell Arteritis) may experience those symptoms as well.
People with temporal arteritis have inflammation of the arteries along one or both sides of the head (along the temples). This can lead to sensitivity, headaches, or twinges of pain along the temples, and in more severe cases it can cause blurry vision or even vision loss.
Diagnosis
Polymyalgia rheumatica (PMR) is best diagnosed by a physician familiar with the condition. This is often a rheumatologist, a type of doctor that is an expert in arthritis and autoimmune disease.
Many diseases can look like PMR so a careful assessment is important. For example, rheumatoid arthritis (RA), some types of cancer, heart infections, and thyroid conditions can cause fatigue and stiffness in areas including the shoulders and hips.
To diagnose PMR, a physician will start by taking a complete history. The disease can be suspected in older patients with a history of pain in the shoulder and hip regions, along with morning stiffness and fatigue. The physician will then perform a thorough physical examination to exclude other conditions. Finally, they will often order blood tests, x-rays, and possibly other types of tests to support the diagnosis.
Common Tests for PMR
Blood Tests
Looking for inflammation: PMR is an inflammatory arthritis so these tests are expected to have abnormal results. Common tests include a Complete Blood Count (CBC), Erythrocyte Sedimentation Rate (ESR), and C-Reactive Protein (CRP).
Looking for other diseases: It is important to rule out other inflammatory diseases when diagnosing PMR. Blood tests including rheumatoid factor, ANA, TSH (thyroid test), and CK (muscle enzyme) should be measured.
Scans
X-rays help rule out other forms of arthritis and confirm a diagnosis of PMR.
Causes
Scientists aren’t sure what causes PMR or why it is a self-limited disease (a disease that goes away on its own) in about half of people but can last much longer and behave like a chronic (long-term) disease in others.
Some theories propose that it might be caused by an external factor like a virus that stimulates the immune system to behave in an undesirable way. If that’s the case, scientists aren’t sure why some people get it but others don’t.
Whatever the cause, PMR causes inflammation in the joints and structures surrounding the joints of the shoulders and hips.
Treatments
Treatment of polymyalgia rheumatica (PMR) usually involves medications to address inflammation as well as physical therapy to keep the joints moving properly. The disease can often by fully and effectively treated with the right therapy, which means it’s possible for people affected by the disease to return to their normal day-to-day lives.
It’s important to treat the disease early to protect and restore a maximum range of motion in the shoulders and hips. If a person with untreated PMR changes their habits and stops using their sore joints in certain ways due to pain and stiffness, the limited movement can lead to contracture, a type of permanent damage involving shortening of the affected muscle or joint.
Physical Therapy and Exercise Treatments for PMR
Physical therapy and the right sorts of exercise can improve the pain and stiffness that people with PMR experience in their shoulders and hips. This treatment helps protect the joints by strengthening the muscles around them and should be done daily to achieve maximum benefit.
Daily exercise can also be helpful in reducing fatigue and any possible emotional distress of the disease.
A trained arthritis physiotherapist can help design an exercise program to return a patient’s shoulders and hips to their full range of motion.
Medications for PMR
Corticosteroids (prednisone)
Prednisone is the main medication used to treat PMR. It works by fighting the inflammation caused by PMR. In most people, symptoms are noticeably better within 24 hours. In some people, their stiffness completely disappears after just one dose.
Once the symptoms of the disease are under control, the dose of prednisone is tapered (gradually reduced). People with PMR usually have to continue taking a low dose of prednisone for at least 1 year to prevent the inflammation from returning.
Stopping prednisone can be difficult for some people because the inflammation can return if it’s stopped too soon. In such cases, doctors might recommend other medications such as NSAIDs or DMARDs to make it easier.
When used for long periods of time, corticosteroids can have side effects. People who take corticosteroids for 3 months or longer are advised to take a daily calcium and vitamin D supplement to protect their bones. Sometimes other medications are also recommended for bone protection. Patients should discuss the risks and benefits of using prednisone with their doctor.
NSAIDs
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) help reduce the inflammation caused by PMR and can also help to reduce pain. They are usually not as effective as prednisone for the initial treatment of PMR, but might be prescribed in addition to prednisone to treat cases that still have symptoms even after being treated with prednisone.
NSAIDs can also help reduce the dose of prednisone in patients who have been taking that medication for a long time.
Analgesics (Pain Killers)
Analgesic medications only control pain, and do nothing to control PMR or prevent further joint damage. Analgesics can range from simple things like acetaminophen (Tylenol) to more potent narcotics like morphine.
DMARDs
Disease Modifying Anti-Rheumatic Drugs (DMARDs) are medications that are frequently used for other types of inflammatory arthritis such as rheumatoid arthritis. Certain DMARDs such as methotrexate or plaquenil can help some patients being treated for PMR reduce their dose of prednisone to help minimize its side effects.