What is complex regional pain syndrome?

Complex regional pain syndrome (CRPS) is a chronic health problem that causes long-lasting pain. Normally, pain is short-term and goes away as the body heals. But with this condition, pain doesn't fade with time. Instead, ongoing pain might get worse instead of better as days and weeks pass.

There are 2 types of CRPS:

• Type-I CRPS is not tied to a direct nerve injury.

• Type-II CRPS occurs after a nerve injury.

What causes complex regional pain syndrome?

Experts aren't sure what causes this syndrome. But they believe that nerve damage is involved. In most cases, the condition occurs after some type of injury to the affected area. But this is not always the case.

Healthcare providers view this disease as an abnormal response by the body. The nerve endings that control pain in an injured part of the body may become too sensitive to the chemical messengers carried by the sympathetic nervous system. These chemical messengers are called catecholamines. They may stimulate the pain and other symptoms. The roles of inflammation and the immune system are also being studied.

What are the symptoms of complex regional pain syndrome?

If you have this syndrome, you may have these symptoms:

• Persistent, burning pain in an arm, leg, hand, foot, or other part of your body

• Mild or severe pain

• Swelling

• Sweating

• Dramatic changes in skin color and skin temperature

• Muscle strength and movement that are less than normal

• Stiffness in affected joints

How is complex regional pain syndrome diagnosed?

There is no specific test to diagnose this syndrome. Your healthcare provider can diagnose it based on your health history, such as having an injury and the symptoms you have. Other conditions can cause similar symptoms. So a careful physical exam is important. Sometimes tests are done to rule out some of these other health problems. Certain tests can help determine if autonomic nerves are injured and linked to the pain.

Autonomic nerve tests can be done to confirm a problem with these nerves. This testing can measure blood flow and sweating among other things.

Your healthcare provider may suggest a sympathetic nerve block. This can help find out if your sympathetic nervous system is causing your pain. It involves injecting an anesthetic into the nerves near the spine. If the nerve block helps your pain, your provider may give you a series of nerve blocks for ongoing relief.

How is complex regional pain syndrome treated?

This syndrome has no cure. But sometimes the symptoms get better or stop on their own. Some evidence suggests early treatment, particularly with physical therapy, can help limit the disease. But this has not yet been proven in studies.

Treatment focuses on easing the pain. It may include:

• Pain medicines

• Antidepressants

• Antiseizure medicines

• Oral steroid medicines

• Sympathetic nerve blocks

• Physical therapy

• Electrical stimulation of the spinal cord or certain nerves

In severe cases, your healthcare provider may inject medicines directly into the fluid around the spinal cord. But it is not clear how well these treatments work.

Living with complex regional pain syndrome

The outcome in CRPS can vary a lot. So it is important that it is diagnosed and treated as soon as possible. You will then have the best chance for a full recovery. Follow your healthcare provider's instructions for taking pain medicines and doing physical therapy or exercising if it is part of your treatment plan.

Physical therapy and exercise that keeps the painful limb or body part moving can often improve blood flow and ease symptoms. It can also help improve the affected limb’s flexibility, strength, and function. If needed, occupational therapy can help you learn new ways to work and do daily tasks.

CRPS can cause emotional or psychological issues for those affected and their families. People with this problem might have depression, anxiety, or posttraumatic stress disorder. All of these can make the pain seem worse and make rehabilitation efforts harder. Let your healthcare provider know how you are feeling. There are often ways to help.

Some other types of therapies have been used to treat other painful conditions. These include behavior changes, acupuncture, chiropractic treatment, relaxation methods, such as biofeedback, progressive muscle relaxation, and guided motion therapy. It is not clear if they are helpful for this syndrome. Talk with your healthcare provider before starting any new type of treatment.

When should I call my healthcare provider?

If you have this syndrome and are being treated, talk with your healthcare provider about when you should call.

Your provider will likely advise you to call if any of your symptoms get worse or if you develop any new symptoms.

Some people with this condition might need strong pain medicines. These can have their own side effects, such as drowsiness, confusion, or changes in consciousness. Let your healthcare provider know if you have these or any other symptoms while taking pain medicines. Your doses might need to be adjusted.

Key points about complex regional pain syndrome

• CRPS is a chronic health problem that causes long-lasting pain. It is often caused by an overreaction in the body to a physical injury.

• Symptoms include constant pain ranging from mild to severe. You may also sometimes have swelling, sweating, and changes in skin color and temperature in the affected area.

• CRPS might go away on its own over time. But in some people, the symptoms can last or even get worse. Common treatments are pain medicines, physical therapy, electrical nerve stimulation, and injections of an anesthetic into the nerves.