What Is Complex Regional Pain Syndrome?

If you are one of the unfortunate few that suffers from complex regional pain syndrome or CRPS, then you have probably struggled with uncertainty about what caused your condition and how long it will continue to afflict you. The good news is that doctors can readily diagnose CRPS, and early treatment can lead to more optimal outcomes.

Complex regional pain syndrome is a pain condition that typically lasts six months or longer.  This condition often affects only one limb and most often follows an injury or surgical procedure.  While some cases involve only mild symptoms and may resolve on their own, in many others, the symptoms are severe and chronic. Some patients may never fully recover—although new treatments are offering a greater chance of recovery—and may experience disability.

CRPS Symptoms

Complex regional pain syndrome is often preceded by an injury in the limb that results in a prolonged and disproportionate burning or “pins and needles” sensation.  This pain may spread to other parts of the limb and, in some cases, even to another limb.  This condition may present as allodynia, in which superficial contact with the skin of the affected area is painful.

The most common symptoms of complex regional pain syndrome include:

  • Skin may appear shiny and thin
  • Abnormal perspiration patterns around the affected area
  • Hair and nails may grow abnormally
  • Affected joints may be stiff
  • Difficulty moving the affected limb
  • Tremors or jerky motions

Causes of CRPS

Although the exact mechanism of complex regional pain syndrome is not fully understood, it is believed that CRPS patients have an abnormal peripheral nervous system.  Peripheral nerves carry impulses to and from the central nervous system.

Many of the more common symptoms associated with complex regional pain syndrome are consistent with peripheral neural anomalies. The red, swollen skin that many CRPS sufferers exhibit may result from over-dilation of blood vessels, allowing fluid to seep into surrounding tissue. Conversely, improper nerve impulses may also trigger blood vessel constriction which results in white or bluish skin.

Another reason peripheral nervous system anomalies is suspected is that there are often immune system issues present in CRPS patients. In many cases, there are high levels of cytokines, an inflammatory response to injury or tissue damage. Furthermore, CRPS is more likely to occur among people suffering from inflammatory or auto-immune conditions.

Diagnosing Complex Regional Pain Syndrome

There is at present no definitive test for CRPS. Most clinicians will make a diagnosis based on a physical evaluation and a thorough analysis of the patient’s medical history. Your doctor is most likely to consider a diagnosis of complex regional pain syndrome if there has been an injury to the affected limb.

It is also important to get tested for some or all of the following conditions so as to rule them out:

  • Lyme disease
  • Arthritis
  • Vein blockage
  • Small fiber polyneuropathies
  • Generalized muscle diseases
  • Nerve entrapment

In some circumstances, an MRI may confirm the presence of excess bone resorption, a telltale sign of CRPS.

It is important to get diagnosed as soon as possible, as earlier intervention is more likely to produce better outcomes. In general, younger people are more likely to fully recover.

Treatments for Complex Regional Pain Syndrome

There are many possible treatment options for complex regional pain syndrome sufferers. 

  • Physical therapy—a consistent exercise program can improve limb strength, flexibility and function. This can counteract some symptoms by promoting blood flow as well as limit changes to the architecture of the brain that often accompany chronic pain. Occupational therapy may also be able to help patients learn new ways to perform common or work-related tasks while still impeded by CRPS.
  • Medications—many drugs have been used to treat complex regional pain syndrome, but there is no FDA-approved drug program specifically for CRPS.  In most cases, your physician may recommend one or more of the following compounds and monitor your progress while on them.
    • NSAIDs-– non-steroidal anti-inflammatory drugs like aspirin, ibuprofen, and naproxen may alleviate pain symptoms
    • Botox—botulinum toxin has helped soothe overactive peripheral nerves
    • Opioids—for patients with more serious pain symptoms, more potent pain killers like opioids may be necessary.  However, opioids should be a last resort and used only for short periods of time.
    • Anti-depressants or anti-seizure drugs—some patients respond well to gabapentin, pregabalin, amitriptyline, nortriptyline, and duloxetine which have proven effective for neuropathy.
  • Psychotherapy—many complex regional pain syndrome patients also experience anxiety, stress and depression which may make pain symptoms stronger. Psychotherapy can help reduce the intensity of these secondary conditions, making the CRPS more manageable.
  • Peripheral nerve stimulation– this procedure places an electrical stimulator near the peripheral nerve. The device produces a weak current that stimulates the peripheral nerve and blocks pain impulses to the brain.
  • Sympathetic nerve block—while not supported by medical evidence, some patients have found pain relief from sympathetic nerve blocks.  A sympathetic nerve block involves an injection of anesthesia into the spine.
  • Spinal cord stimulation—this procedure places an electrical stimulator near the spine.  The device produces a weak current that stimulate spinal nerves and block pain impulses to the brain.
  • Surgical sympathectomy—this procedure is only for CRPS patients who have tried all other therapies without success.  A surgical sympathectomy destroys the nerves producing the pain sensations. In many cases, this may actually worsen CRPS symptoms.

The Future of CRPS Treatment

Many of the current treatments for complex regional pain syndrome are intended to remedy the symptoms like chronic pain, but as more research into CRPS is completed, new treatment options should become available.

Of the most promising fields of research are peripheral nerve damage studies. The most common precursor for CRPS is limb trauma including bone fractures, so there is some evidence that inflammation may play a strong role in the onset of complex regional pain syndrome.

There is also interest in why children and teens are more likely to fully recover from CRPS. This suggests that there may be some developmental mechanisms that ward off CRPS.

Article written by: Dr. Robert Moghim – CEO/Founder Colorado Pain Care

M.D. Disclaimer: The views expressed in this article are the personal views of Robert Moghim, M.D. and do not necessarily represent and are not intended to represent the views of the company or its employees.  The information contained in this article does not constitute medical advice, nor does reading or accessing this information create a patient-provider relationship.  Comments that you post will be shared with all visitors to this page. The comment feature is not governed by HIPAA and you should not post any of your private health information.