Complex Regional Pain Syndrome (CRPS)

Imagine a condition that comes on mysteriously and results in not only incredible pain but also physical and sensory changes to the skin itself. Complex regional pain syndrome is a rare but excruciatingly painful condition that is challenging to diagnose and as complex to treat as its name would suggest. Here’s what you should know.

What is complex regional pain syndrome?

Complex regional pain syndrome (CRPS) causes tremendous and often debilitating pain. Known also as Sudeck’s atrophy, causalgia, reflex sympathetic dystrophy (RDS), shoulder-hand syndrome, post-traumatic dystrophy, and reflex neurovascular dystrophy, CRPS is a chronic pain and sensory condition that typically affects the upper and lower extremities (arms and legs).

Nerve damage in the affected extremity causes the brain to send confusing and incorrect pain signals. The resulting condition is ranked as one of the most painful chronic pain conditions, more painful than amputation and childbirth.

Complex regional pain syndrome symptoms

Complex regional pain syndrome symptoms need not all be present, but many people experience most of the following:

  • Skin discoloration
  • Consistent pain that lasts for three months or more, described as throbbing or burning
  • Increased sensitivity to cold or pressure
  • Swelling in the affected extremities
  • Rapid temperature changes (i.e., feeling cold one minute and hot or sweaty the next)
  • Changes in hair or nail growth
  • Increased joint immobility or inflexibility
  • Muscular spasms
  • Muscular atrophy (i.e. loss of muscular tone or strength)
  • Impaired mobility in the affected body part(s)

The two hallmark symptoms of complex regional pain syndrome are allodynia and hyperalgesia. Allodynia is when pain is produced by a stimulus that is not usually painful (e.g., when a breeze blows across your skin). In hyperalgesia, a normally painful stimulus causes much more irritation and pain than would be typically produced (so a minor scratch would feel like a deep gouge).

Both allodynia and hyperalgesia occur as a mixed-up interaction between the peripheral nervous system (PNS) and the central nervous system (CNS). Local tissue injury and inflammation activate the PNS, which sends signals through the spinal cord and to the brain. There is an increase in the excitability of neurons within the CNS so that normal inputs from the PNS begin to produce abnormal responses.

Low-threshold sensory fibers activated by light touch excites neurons in the spinal cord that normally only respond to noxious (painful), or more severe, stimuli. As a result, an input that would normally produce a harmless sensation now produces significant pain.

Women are more likely to suffer than men, with the average age of sufferers of both gender between the ages of 40-60.

Some researchers also believe that emotional distress can increase the severity of symptoms. Over time, if CRPS is not treated, symptoms can become irreversible.

What causes complex regional pain syndrome?

There are two types of CRPS with similar signs and symptoms that are differentiated by their causes.

  • Type I: CRPS I is the most common type and likely occurs due to trauma to an area. This type also produces vasomotor disturbances (changes in skin color and temperature, like a hot flash).
  • Type II: CRPS II occurs after a direct and specific nerve injury and is much less common.

CRPS often occurs after trauma to an arm or leg. Major traumas include car accidents, penetrating wounds, and crush injuries. Other traumas can include surgery, infection, and fractures, all of which can lead to complex regional pain syndrome.

Do I have CRPS?

As with many pain conditions, it can be hard to get a diagnosis. To start, your physician performs a physical examination to look for tenderness over certain areas as well to assess any limitations in movement. They will evaluate the extent of your restricted movements, the amount of pain produced, and your sensory function.

Depending on your medical history, your physician may also order an X-ray, CT scan, MRI, or bone scan. This looks for soft tissue injury or trauma as well as any bone fractures that might be causing symptoms.

In some cases, certain types of trauma should automatically be referred for evaluation by a pain specialist. Distal radial fractures increase the chances of CRPS occurring by 10%, a small percentage but mighty when other risk factors are also present.

Because complex regional pain syndrome is rare and ultimately incurable, timely diagnosis is important to help your manage symptoms and provide relief.

What complex regional pain syndrome treatments work?

Arizona Pain offers treatments for complex regional pain syndrome, many of which are not found anywhere else in the Valley. These treatments are individualized to each patient and include the following.

crps treatments

Physical therapy

In order to decrease or prevent functional limitations, your doctor may recommend physical therapy and occupational therapy in conjunction with other treatments.

Physical therapy focuses on exercising the affected limbs, improving range of motion and strength.


Biofeedback teaches patients with CRPS to have a better awareness and familiarity with their body.

When they recognize the physical symptoms of pain (i.e., increased heart rate and sweating) they can respond with specific techniques designed to provide relief.

Support groups

Living with a chronic pain condition can be extremely difficult. People with CRPS have an exceptionally difficult time because others do not understand the amount of pain that they experience. In some cases, CRPS is an invisible illness that others just don’t understand.

A CRPS support group know what you’re going through and can help you feel supported as you seek treatment.

Complementary medicine

Therapeutic massage and acupuncture are treatments that we offer at Arizona Pain for stress relief and relaxation.

Pharmacological treatments

Important, pharmacological treatments for medical management of CRPS can be membrane stabilizing drugs or NSAIDs.

Sympathetic nerve blocks

With this procedure, your doctor inserts a small, fine needle through the skin to the origins of the sympathetic nervous system. When the nerves are blocked, pain relief can be dramatic for some individuals.

Procedures that focus on the face and upper extremities include the stellate ganglion block and brachial plexus nerve block. Lumbar sympathetic nerve blocks are commonly useful for CRPS in the lower extremities.

Infusion techniques

This procedure involves inserting a small catheter through a needle into the epidural space or directly next to damaged nerves.

Local anesthetic and other medicines are often given through the catheter for extended time periods. By blocking the nerves continuously with an infusion, pain relief can be dramatic and long-lasting.

Spinal cord stimulation (SCS)

Spinal cord stimulation uses tiny electrodes implanted within the epidural space close to the spinal cord. The electrodes release a small electrical current to the spinal cord that inhibits pain transmission, thereby providing pain relief.

In one small-scale study of military personal with CRPS, the use of SCS was positively correlated with a significant decrease in pain and a decreased use of opioids.

Peripheral nerve stimulation

This method involves your doctor placing tiny electrodes close to the affected nerves. The electrodes release a small electrical current that inhibits pain transmission and provides pain relief.


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