Complex Regional Pain Syndrome


What is Complex Regional Pain Syndrome?

By Lisa Hurley


Complex Regional Pain Syndrome (CRPS) is a rare, progressive,  neuropathic condition related to peripheral nerve injuries. It is considered to be the most painful chronic pain condition known to modern medicine.  CRPS has historically been known as Algodystrophy, Causalgia, Neurodystrophy, Post-traumatic Dystrophy, Reflex Neurovascular Dystrophy (RND), Reflex Sympathetic Dystrophy (RSD), and Sudek’s Atrophy, however the International Association for the Study of Pain has standardized the name to Complex Regional Pain Syndrome in order to simplify and standardize diagnoses but you will sometimes still hear the disorder called by these alternate terms today.


The precise number of CRPS sufferers is unknown, however estimates that the syndrome affects 26 of every 100,000 people. Although CRPS can occur anywhere in the body, it is most frequently diagnosed in the extremities such as arms, hands, legs, and feet.

Pain Image 1

What causes CRPS?

In most cases, the condition is caused by some form of physical trauma to the body that adversely affects the peripheral nervous system. For example crush injuries, blunt or sharp-force trauma, prolonged immobilization, surgery, amputations, fractures, falls, strokes, heart attacks, or even bad sprains can result in a patient developing Complex Regional Pain Syndrome.

There are still some cases of CRPS that are not the result of either trauma or an identifiable nerve injury. These are most often attributed to an exaggerated immune system or inflammatory response.

Are there risk factors?

According to the National Library of Medicine at the U.S. National Institue of Health (NLM/NIH), risk factors for the condition can include ACE-inhibitor therapy, asthma, elevated intracast pressure, migraine, menopause, and osteoporosis. In addition, smokers are likely to have a higher risk factor vs. non-smokers.

Who gets CRPS?

There are no known age, gender, or genetic restrictions on who can develop CRPS, but the condition occurs most frequently in people ranging in age from the mid-30s to early 40s, and is three times more likely to occur in women than men. CRPS is rare among very young children (under 5 years old), and in the elderly (over 70 years old).

Types of CRPS

There are two major forms of CRPS: Type 1 and Type 2. Both types occur most frequently in the extremities of the body, although there have been cases of the condition spreading to other areas. The main difference between the two forms lies in how they develop:

     Type 1 CRPS occurs after an injury or illness that did not directly damage the nerves in the affected limb; that is, trauma occurs remotely from the affected area. This form of the condition used to be known as Reflex Sympathetic Dystrophy Syndrome. This is the most frequently occurring form of the condition.

     Type 2 CRPS results from a direct injury to a major nerve of the affected limb. This form of the condition used to be known as Causalgia, and is more rare than Type 1.

What are the symptoms of CRPS?

As its name implies, Complex Regional Pain Syndrome is characterized by a variety of symptoms, including but not limited to pain (clearly), sensory disturbances, autonomic disorders, inflammatory responses, trophic changes, and motor dysfunction:

  • Pain
  • Burning, neuropathic, dull, spontaneous and/or constant. Sometimes triggered by movement, pressure, or loud noises.
  • Sensory Disturbances
  • Allodynia, or pain from stimuli that ordinarily would not cause pain. Allodynia can be tactile, thermal, or mechanical.
  • Hyperalgesia (Patient becomes more sensitive to painful stimuli due to the use of opiod pain medication.)
  • Hypersensitivity of the skin, even to very light touch/sensation from stimuli such as air or feathers.
  • Autonomic Disorders
  • Color changes is skin (very red, or very pale).
  • Hyperhidrosis (excessive sweating) and other changes in perspiration.
  • Cold, clammy skin on the affected limb.
  • Abnormal blood flow to the skin of the affected area
  • Inflammatory Responses
  • Increased temperature.
  • Edema.
  • Swelling.
  • Erythema (reddening of the skin).
  • Trophic Changes
  • Hair growth markedly increases or decreases.
  • Nails become thick and brittle nails.
  • Skin becomes smooth, clammy, thin, mottled.
  • Fibrosis.
  • Osteoporosis.
  • Acute arthritis.
  • Motor Dysfunction
  • Muscle weakness and stiffness.
  • Reduced range of motion.
  • Tremor.
  • Stiffness.
  • Atrophy.
  • Dystonia (involuntary muscle spasm).
  • Loss of the ability to move the affected limb.

What are the Stages of CRPS

The syndrome typically develops in three phases:


Stage 1 usually begins a few days after the trauma, injury or surgery, and lasts up to six months. It is characterized by:

  • extreme pain
  • a burning or aching sensation
  • edema
  • accelerated growth of the nails and hair
  • changes in skin color & temperature


Stage 2 usually begins three to six months after the initial onset of pain, and lasts for about six months. Symptoms             during this phase include:

  • increased, constant pain
  • reduced muscle tone
  • joint stiffness
  • rigid, thinning nails
  • osteoporosis


Stage 3 typically starts six to twelve months after the initial experience of pain. This stage can last for years, and there is     also the possibility that the condition might resolve and reappear later. This phase is characterized by:

  • Stiffer joints
  • Pain over a wider area of the body
  • A plateau in pain intensity
  • Stiffness/immobility of the affected limb
  • Additional loss of muscle tone
  • Contractures
  • Cool, thin, dry skin

What does CRPS pain feel like?

In terms of intensity, CRPS pain is ranked 42 out of 50 on the McGill Pain Scale—more painful than having a finger amputated without anesthesia.

In terms of sensation, many CRPS sufferers describe the pain as being significantly out of proportion to the original injury. The pain is also described as intense, burning, and constant.


What Treatments are available for CRPS?


Treatment protocols for Complex Regional Pain Syndrome typically involve a synergistic combination of physical and occupational therapy, pain management/medical therapy, and psychological therapy, designed to reduce pain, increase mobility/function, and improve quality of life. This partial list of some therapies that have been used can serve as a reference that patients can use when consulting with their medical team:

  • Physical/Occupational Therapy
  • Contrast baths
  • TENS (Transcutaneous Electrical Nerve Stimulation)
  • Massage
  • Stretching
  • Ultrasound therapy
  • Isometric strengthening exercises
  • Gradual weight bearing/stress loading
  • Aquatic Therapy
  • Mirror-Box Therapy
  • Lymphatic drainage
  • Desensitization therapy
  • Endurance training
  • Functional training
  • Acupuncture
  • Medical Therapy
  • Opioids
  • Cortico-steroids
  • NSAIDs
  • OTC pain medications
  • Intravenous ketamine
  • Anti-convulsants
  • Nerve-blockers
  • Anti-depressants such as SSRIs and TCAs
  • Sodium-channel blockers
  • Calcium-channel blockers
  • Sleeping aids
  • Topical analgesics
  • Spinal cord stimulation
  • Psychological Therapyfriends
    Chronic, intense pain can have an adverse impact on a patient’s mood, and quality of life, as it can be emotionally burdensome to deal with the effects of the pain. Psychological therapy should therefore be included as a part of a patient’s treatment regimen as early as possible after diagnosis.
  • Talk therapy
  • Cognitive Behavioral Therapy (CBT)
  • Alternative Therapies
  • Meditation
  • Relaxation techniques

Is there a Cure?

There is no known cure for Complex Regional Pain Syndrome, but early diagnosis and a well-planned, multi-disciplinary treatment protocol can make a positive difference. In addition, having a strong support network can help. Staying connected to loved ones, joining a support group, and participating in talk therapy can help patients cope.



Lisa Hurley is a writer, Reiki practitioner, and certified sun-seeker. She is originally from Barbados, and now lives in Jersey City, New Jersey with her Jack Russell terrier King. She also happens to have an invisible illness (uveitis), and a chronic pain condition. She is passionate about helping other chronic pain warriors find the information they need to navigate their struggles, and feel stronger, more supported, and less alone.
Lisa’s educational background includes a Bachelor’s in French, Spanish & Linguistics from the University of the West Indies, a Master’s in Music Business from New York University, and a Mini-MBA™ in Social Media from Rutgers University.
If you’d like to connect with Lisa, you can find her on Instagram, Facebook, and LinkedIn.



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