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Disease Profile

Complex regional pain syndrome

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset

All ages



G90.5 G90.6


Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

CRPS; Reflex sympathetic dystrophy


Nervous System Diseases


Complex regional pain syndrome (CRPS) is a chronic pain condition that mainly affects the arms, legs, hands, and feet, but may involve the entire body. CRPS symptoms often begin after surgery or an injury.[1] The main feature of CRPS is continuous, intense pain that is out of proportion to the severity of the injury. The pain gets worse over time and often spreads throughout the entire affected area.[2] Other symptoms may include color and temperature changes of the skin over the affected area; skin sensitivity; sweating; and swelling.[1] The underlying cause of CRPS is often not known. Two classifications of CRPS have been recognized based on causalgia. Type I (also known as reflex sympathetic dystrophy), in which there is no evidence of peripheral nerve injury and Type II, in which peripheral nerve injury is present. Treatment aims to relieve pain and often includes different interventions such as topical or oral medications; physical therapy; and/or a sympathetic nerve block.[2][3]


Complex regional pain syndrome (CRPS) usually develops after an injury, surgery, stroke or heart attack.[4] The key symptom of CRPS is continuous, intense pain that is out of proportion to the severity of the injury. The pain gets worse over time. CRPS most often affects one of the arms, legs, hands, or feet, and the pain often spreads throughout the entire affected arm or leg.[2] Other signs and symptoms may include:[4]

  • sensitivity to touch or cold
  • swelling of the painful area
  • changes in skin temperature, color, and/or texture
  • joint stiffness and swelling
  • muscle weakness and/or muscle spasms

Symptoms may change over time and vary from person to person. In some people, signs and symptoms of go away on their own. In others, symptoms can persist for months to years.[4]

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
80%-99% of people have these symptoms
Limb pain
30%-79% of people have these symptoms
Abnormality of hair growth
Dry skin
Edema of the upper limbs
Fluid accumulation in upper limbs
Involuntary movements
Involuntary muscle contractions
Pedal edema
Fluid accumulation in lower limbs
Lower leg swelling

[ more ]

Slow-growing nails
Trophic changes related to pain


The underlying cause of complex regional pain syndrome (CRPS) is not well understood. In most cases it occurs after an illness or injury that did not directly damage the nerves in the affected area (Type I). In some cases, it occurs after a specific nerve injury (Type II). The exact trigger of CRPS after an injury is not known, but it may be due to abnormal interactions between the central and peripheral nervous systems, and/or inappropriate inflammatory responses.[3]


Treatment of complex regional pain syndrome (CRPS) involves a multidisciplinary approach with the aim of controlling pain symptoms. It has been suggested that when treatment is started within a few months of when symptoms begin, improvement or remission may be possible.[3]

A combination of therapies is usually necessary including medications, physical and occupational therapy, interventional procedures, and psychosocial/behavioral management. 

Medications may include:

  • Oral and topical pain relievers
  • Antidepressants or anticonvulsants (which are sometimes used to treat pain)
  • Corticosteroids
  • Bone-loss medications
  • Sympathetic nerve-blocking medications
  • Intravenous anesthetics (Ketamine)
  • Intravenous immunoglobulin

Interventional procedures may include:

Other therapies may include applying heat or cold; electrical nerve stimulation; and biofeedback.[2][3]

Psychosocial and behavioral aspects of CRPS should be addressed, and it has been suggested that people with chronic CRPS should have a thorough psychological evaluation. This may be followed by cognitive-behavioral pain management, including relaxation training with biofeedback.[5]

Unfortunately, published research studies validating the efficacy of these treatment options are limited and no single drug or therapy (or combination) has shown consistent, long-lasting improvement.[2][3]

For more information on treatment options for CRPS, view information from the Reflex Sympathetic Dystrophy Association of America (RSDSA).


Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

    Social Networking Websites

      Learn more

      These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

      Where to Start

        In-Depth Information

        • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
        • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
        • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
        • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
        • PubMed is a searchable database of medical literature and lists journal articles that discuss Complex regional pain syndrome. Click on the link to view a sample search on this topic.


          1. Telltale Signs and Symptoms of CRPS/RSD. Reflex Sympathetic Dystrophy Syndrome Association of America (RSDSA). 2015; https://rsds.org/telltale-signs-and-symptoms-of-crpsrsd/.
          2. NINDS Complex Regional Pain Syndrome Information Page. NINDS. November 3, 2015; https://www.ninds.nih.gov/disorders/reflex_sympathetic_dystrophy/reflex_sympathetic_dystrophy.htm.
          3. Salahadin Abdi. Complex regional pain syndrome in adults: Prevention and management. UpToDate. Jan 06, 2016; https://www.uptodate.com/contents/complex-regional-pain-syndrome-in-adults-prevention-and-management.
          4. Complex regional pain syndrome. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/complex-regional-pain-syndrome/basics/definition/con-20022844. Accessed 11/11/2014.
          5. Bruehl, S and Chung OY. Psychological and Behavioral Aspects of Complex Regional Pain Syndrome Management. Clinical Journal of Pain. June, 2006; 22(5):430-437. https://journals.lww.com/clinicalpain/Abstract/2006/06000/Psychological_and_Behavioral_Aspects_of_Complex.5.aspx.
          6. David D. Sherry. Complex regional pain syndrome in children. UpToDate. Waltham, MA: UpToDate; November, 2014; Accessed 11/11/2014.

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