What Is Complex Regional Pain Syndrome (CRPS)?

Managing Chronic Pain Symptoms in CRPS Types 1 and 2

Complex regional pain syndrome (CRPS) is a neurological condition that can be life-altering, causing long-term pain and inflammation. Marked by symptoms of pain, swelling, muscle weakness, burning sensations, and changes in skin temperature, the chronic or ongoing pain of CRPS can lead to depression and feelings of isolation.

CRPS typically occurs after a nerve injury or other trauma. The symptoms of CRPS can vary and be quite painful. Often, it is difficult to diagnose CRPS. Diagnosis is based on meeting a set of criteria, but there is no known test for the syndrome.

Although CRPS can be unpredictable, there are ways to manage the pain and other symptoms.

Continue reading to learn the types of CRPS, how to manage the pain, criteria for diagnosis, treatment options, long-term effects of the syndrome, and how to assemble a team of professionals to help with care.

An illustration of a person suffering from leg pain from Complex Regional Pain Syndrome (CRPS).

Illustration by Michela Buttignol for Verywell Health

Types of Complex Regional Pain Syndrome (CRPS)

CRPS has two types. Both types occur after an injury, illness, or medical event such as surgery, stroke, or heart attack.

CRPS Type 1

In CRPS type 1, there is no specific nerve damage after the initial event. Most cases of CRPS are type 1. People with type 1 can experience a myriad of symptoms that can be constant or come and go.

These symptoms include:

  • Burning or pins and needles sensations
  • Sudden pain
  • Pain that occurs with a light touch
  • Long-lasting pain after a small pain like a pinprick
  • Pain while using affected limbs
  • Swelling in the affected area
  • Skin color changes—blotchiness, blue, purple, gray, pale or red
  • Changes in sweating—patches of increased sweating or no sweating
  • Changes in hair and nail growth
  • Bone changes
  • Weakness in affected limbs
  • Tremor
  • Dystonia, an abnormal posture due to involuntary muscle contraction

 CRPS Type 2

CRPS type 2 is associated with damage to a specific nerve. Symptoms of type 2 are similar to type 1, but the origin of the pain may be easier to detect.

Progression of CRPS

CRPS develops in two phases. The first phase is the acute, or short term, phase with symptoms such as inflammation and pain. The second phase is the chronic phase and is marked by changes in soft tissues and bone, which can lead to disability.

Injuries Associated With CRPS

Injuries that may damage the nerves are more prone to developing CRPS. Several injuries are commonly associated with CRPS. These include but aren’t limited to:

 Theories About Causes

Though CRPS typically develops after a trauma or injury, the underlying cause is not fully known. A variety of factors seem to contribute to the complex nature of CRPS. These include:

  • Inflammation: Inflammation of the tissues, nerves, and brain may all play a part in developing CRPS. Trauma to the skin, bones, and connective tissue triggers an inflammatory response that appears to be exaggerated in CRPS. Inflammation may also occur in the brain and spinal cord and is thought to be another contributor.
  • Autonomic system: The sympathetic nervous system, responsible for the fight-or-flight response, does not function properly in people with CRPS, causing increased pain, higher heart rate, and changes in skin temperature.
  • Central nervous system and brain changes: In CRPS, it is believed that parts of the brain rewire themselves in a way that produces more pain after the initial trauma.
  • Psychological factors: People with CRPS who had pain and depression were found to experience more disability. While mental health issues do not predict whether someone develops CRPS, it has been shown that people who experience more life events have a higher probability of developing CRPS.
  • Autoimmunity: Some evidence shows that CRPS may involve an an autoimmune response, in which the immune system mistakenly attacks the body instead of protecting it from foreign invaders like viruses and bacteria.

Other Risk Factors 

Other risk factors may make someone more susceptible to developing CRPS. These include:

  • Females, especially those who are postmenopausal (time after menopause, when menstrual periods have stopped for 12 straight months)
  • Experiencing a dislocated ankle or fracture
  • Having a limb immobilized, such as being in a cast
  • Experiencing unusually high levels of pain during the early phases of a trauma or injury
  • Genetics, in that people who have family members with CRPS may be more at risk for developing the syndrome
  • Smoking
  • Experiencing prior nerve damage
  • Poor circulation
  • Diabetes
  • Autoimmune disorders

A Note on Gender and Sex Terminology

Verywell Health acknowledges that sex and gender are related concepts, but they are not the same. To reflect our sources accurately, this article uses terms like “female,” “male,” “woman,” and “man” as the sources use them.

How CRPS Gets Diagnosed

No single test is sufficient to diagnose CRPS. A healthcare provider will take a history of symptoms and look for other signs to meet specific criteria. These are known as the Budapest criteria, developed during a workshop on CRPS in Budapest in 2003.

To be diagnosed with CRPS, a person must meet all four of the following criteria:

1) Have continuous pain that is disproportionate to the original injury or trauma.

2) Have at least one symptom in three or more of these categories:

  • Sensory: Extreme sensitivity to touch, pain from a situation that normally wouldn’t produce pain, such as a feather touching the skin
  • Vasomotor: Inconsistent temperatures of the skin (like a cold right arm and hot left arm), changes in skin color, asymmetric skin discoloration
  • Sudomotor: Swelling, increased sweating, asymmetric sweating
  • Motor: Weakness, decreased range of motion, shaking or tremor, dystonia, changes in the skin, nails, and hair, such as pitting of the nails and hair overgrowth

3) Have at least one sign present during evaluation in two or more of the same categories listed above; a healthcare provider must see that two or more of these symptoms are present during the evaluation

4) Have no other diagnosis that could better explain the current symptoms and signs

A Difficult Diagnosis

Because CRPS is diagnosed based on a set of criteria and symptoms come and go, the unpredictable nature of the syndrome makes it difficult for many people to receive a timely diagnosis. The diagnostic criteria weren’t developed until 1994 and were revised in 2010. Until that point, CRPS had other names, such as reflex sympathetic dystrophy syndrome.

CRPS Treatment Approaches

While there is no cure for CRPS, treatment options are available to help manage chronic pain and other symptoms. These include:

  • Therapy: Physical and occupational therapy can help with mobility and maintenance of day-to-day functions such as getting dressed.
  • Medications: Neuropathic pain, or pain caused by nerve damage, can be treated with a variety of medications. These include Neurontin (gabapentin), tricyclic antidepressants, and Tegretol (carbamazepine). For muscle stiffness or spasticity, Ozobax (baclofen) can help.
  • Steroids: In some cases, steroids can help with pain caused by inflammation. Long-term steroid treatment, however, is not recommended.
  • Nerve block: Pain not relieved by therapy and medication may be treated with a nerve block, a procedure that blocks pain from specific nerves.
  • Nerve stimulation: This procedure stimulates the affected nerve or surrounding nerves, such as those in the spinal cord, to block pain signals.

Chronic Pain Management in CRPS

Due to the complex nature of CRPS, often multiple treatments are required. Managing chronic pain becomes a top priority for people living with the syndrome to improve their quality of life and minimize distress.

Pain management is accomplished with a variety of options, including medications, physical therapy, nerve blocks, and nerve stimulation.

Bisphosphonates are a class of drugs typically used for osteoporosis that have been proven to help with CRPS pain in some Italian studies. Some of these medications, such as neridronate and clodronate, are not available to people in the United States.

Long-Term Effects of CRPS

While most people with CRPS will improve over time, others may still live with some level of pain. The severity of CRPS depends on the severity of the original injury. Young people and healthy adults with good circulation and healthy eating habits often have less severe cases and frequently recover fully.

People who smoke, have diabetes, or who have previously been treated with chemotherapy may have a more difficult time recovering.

Severe or long-lasting cases can be disabling, making it difficult to carry out everyday tasks. Chronic or long-term cases can also affect mental health.

Finding a Multidisciplinary CRPS Team 

Living with CRPS can affect the emotional, social, and physical aspects of life. Finding a multidisciplinary team can help you live well with the syndrome. Consider the following:

  • Finding a provider who can assess and diagnose CRPS is a great start for the CRPS team. This person can point you in the right direction to help you manage all aspects of living with CRPS.
  • Physical and occupational therapists can help with the physical aspects of the disease. They can provide exercises to manage pain and mobility and tools to help navigate tasks of daily living.
  • A pain specialist can help with managing the pain.
  • A mental health professional can help you cope with the emotional drains and stresses of living with chronic pain and provide coping tools to help adapt to a new normal.
  • Finding a support group in person or online can also be helpful.

Summary

CRPS is a neurological condition that can cause chronic pain and other symptoms. CRPS typically develops after an injury or trauma. There are two types of CRPS—type 1 and type 2. Type 1 is not associated with damage to a specific nerve; type 2 is associated with specific nerve damage.

Symptoms of the syndrome include pain, a heightened response to touch, burning sensations, changes in hair and nail growth, loss of movement, and muscular and bone changes.

While the origin of CRPS is not fully known, there is some understanding that inflammation, the sympathetic nervous system, brain changes, and autoimmunity may all play a part in the development of the disorder.

Genetics may also play a part in the disease. Females, people who have experienced an ankle fracture, smoking, experiencing high levels of pain at the onset of the injury, and having a cast or immobilized limb are all factors that can increase the likelihood of developing CRPS.

CRPS is often hard to diagnose and is done through the Budapest criteria. Treatment may include therapy, medications, nerve blocks, and nerve stimulation.

Although there is no cure for CRPS, it often improves over time. Having a care team to manage the effects of the syndrome can help improve the quality of life with the syndrome.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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