Complex regional pain syndrome is an uncommon form of chronic pain that usually affects an arm or leg. Complex regional pain syndrome typically develops after an injury, surgery, stroke or heart attack, but the pain is out of proportion to the severity of the initial injury, if any injury can be identified at all. Typical symptoms include prolonged or excessive pain and mild to dramatic changes in skin color, temperature, and mild to severe swelling of the affected area.

Who can get CRPS/RSD?

Women are much more likely to get CRPS, however men and children can develop this pain syndrome. The average age of affected individuals is 40 years old. Children under 5 do not develop CRPS and only in very rare cases does it develop before age 10. It is not uncommon, however, in teenagers.

Causes of CRPS/RSD

The cause of complex regional pain syndrome isn't clearly understood. Treatment for complex regional pain syndrome is most effective when started early. In such cases, improvement and even remission are possible. Neuromodulation therapy represents a great advancement in the treatment of CRPS/RSD.

Most cases (90%) of complex regional pain syndrome occur after a forceful trauma to an arm or a leg, such as a crush injury, fracture or amputation. Other major and minor traumas — such as surgery, heart attacks, burns, infections and even sprained ankles — also can lead to complex regional pain syndrome. Trauma experienced during automobile accidents sometimes may lead to an onset of this disease. Emotional stress may be a precipitating factor, as well. Limb immobilization, such as being in a cast, is also a known trigger.

It's not well understood why these injuries can trigger complex regional pain syndrome, but it may be due to a dysfunctional interaction between your central and peripheral nervous systems and inappropriate vascular and inflammatory responses. It is suspected that damage to the very small nerve fibers that communicate to blood vessels and also communicate pain messages to the central nervous system may be to blame. Molecules that are secreted from the small damaged nerve tissues are thought to contribute to inflammation and blood vessel abnormalities.p>

CRPS also affects the immune system and more commonly occurs in individuals with other inflammatory and autoimmune conditions, such as asthma.

Possible Mechanism of CRPS

Symptoms of CRPS/RSD

The hallmark symptom is prolonged and often constant pain. The pain may feel like a burning, squeezing or “pins and needles” sensation. The pain may start with just a portion of the affected limb, but can spread to affect the entire limb. In severe cases the pain and other symptoms can spread to the opposite side limb. There is often a heightened sensitivity in the affected limb to even light touch. This is called allodynia.

CRPS is also characterized by constant or intermittent changes in temperature, skin color and swelling of the affected limb. Damage to the small nerve fibers that control blood flow are to blame for these symptoms. The skin on the affected limb may change color from blue, to purple, to pale or red.

Other common features of CRPS include:

  • Changes in skin texture on the affected area. Skin may appear shiny and thin
  • Abnormal sweating in the affected area
  • Nail and hair growth changes
  • Stiffness in affected joints
  • Difficulty coordinating muscle movement
  • Abnormal movement in the affected limb, which can be fixed in an abnormal posture (dystonia)
  • Tremors or uncontrollable jerking of affected limb
Prognosis & Complications

Almost all children and teenagers will have a good recovery. Occasionally in adults, CRPS will progress in severity to leave the sufferer with unremitting pain, swelling, dysfunction and disability. Irreversible changes can occur, such as tissue wasting and muscle contracture, despite all treatment efforts. Early treatment, particularly rehabilitation, seems to lend to the best outcomes.

If complex regional pain syndrome is not diagnosed and treated early, the disease may progress to more disabling signs and symptoms. These may include:


  • Rehabilitation therapy. Will help improve blood flow and lessen circulatory symptoms. Improved strength, flexibility and function usually result. Rehabilitation can also help prevent and reverse brain changes that become associated with chronic pain patterns.
  • Pharmacological Intervention NSAIDs, corticosteroids (used early in treatment), and neuropathic pain medications are most commonly utilized. Opiod drugs are last resort.
  • Sympathetic Nerve Blocks. Many individuals report improvement in symptoms following injection of an anesthetic medication next to the spine to directly block the activity of the sympathetic nerves and to improve blood flow. This is one of the procedures that Novocur may employ to offer relief.
  • Neuromodulation Therapy. Modulating how the nerves in our body work either at the level of the spine or peripherally through Neuromodulation technology represents a dramatic improvement in treatment capability at Novocur. Dramatic alterations in CRPS symptoms can be obtained through the implantation of thin electrodes over affected nerves or nerve centers. These electrodes are programmable to achieve desired changes in the affected body part only. Novocur is a leader in this type of treatment often collaborating with Neurosurgeons to determine if this treatment may work for your CRPS/RSD.

Just Prior to Neurostimulation Treatment

Immediately Following Neurostimulation Treatment

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