CRPS/RSD Overview

Complex Regional Pain Syndrome/Reflex Sympathetic Dystrophy

CRPS (complex regional pain syndrome) used to be called RSD, or reflex sympathetic dystrophy. The name was changed in the mid-1990s, but you may still hear CRPS called RSD. It is estimated that 50,000 new cases of CRPS occur each year in the United States.

People with CRPS experience intense pain in their limbs, hands, and feet, as well as changes in skin color, temperature (first warm, then cold), and loss of movement or function. In most cases, the pain is constant. For example, approximately 2 to 5% of patients with peripheral nerve injury and approximately 12 to 21% of patients with partial paralysis develop CRPS as a complication, according to the Reflex Sympathetic Dystrophy Syndrome Association (RSDSA). There may also be changes in hair and nail growth in the affected limb.

CRPS sometimes starts spontaneously, but it usually occurs after an injury—usually a fracture. While it is unusual, some patients develop CRPS after a stroke, heart attack, surgery, or other condition. The syndrome is somewhat mysterious because:

  • patients’ pain is often greater than one would expect from the injury they received (hyperalgesia),
  • patients are more sensitivity to a stimulus (hyperesthesia)
  • patients may experience pain to a non-painful event (allodynia)
  • the pain continues for months or years after an injury appears healed

Physicians and neuroscientists do not know why patients’ nervous systems malfunction and broadcast fierce pain signals, causing CRPS. In fact, there is usually a lack of a specific nerve injury (or trigger)

Despite its mysterious attributes, few doubt CRPS’s actual existence or try to write it off as a psychological phenomenon. Small children, without the skill or intent to fake such a condition, have developed CRPS. Moreover, the changes to victims’ skin, hair, nails and bones dismiss any such faulty notions.

CRPS Symptoms: Intense Pain

The main symptom of CRPS is continuous and intense pain in the feet, legs, arms, or hands. The pain gets worse over time, and frequently spreads to another extremity or area of the body. Patients often describe the pain as a burning sensation.

Other CRPS symptoms may include:

  • joint stiffness, inflammation, and swelling
  • discoloration and skin surface changes
  • swift hair growth
  • altered finger and toenails
  • trouble moving the affected arm, leg, foot, or hand


Medical experts have not yet uncovered the cause of CRPS.

Some of their theories include:

  • The neurochemical norepinephrine over-activates pain sensors for no apparent reason, or as an overreaction to an injury.
  • Inflammation damages small-fiber nerves
  • The patient’s immune system is somehow triggering the pain mechanisms.

However, experts are quick to point out that there are probably a number of events, happening together, to set off the painful responses in CRPS patients.

Does CRPS Heal?
In most cases, CPRS is a permanent condition. When CPRS is diagnosed and treated early, there is a chance it can disappear permanently. Nevertheless, with most patients the goal is to reduce the pain and slow down the symptoms. Learning how to cope with some pain and learn to live a full life with some symptoms is key to successful management.

Doctors Who Treat CRPS/RSD
If you or a loved one are living with CRPS, a neurologist or neuropsychiatrist needs to be the doctor who manages your CRPS care. You may also add a pain management specialist, rheumatologist, and other key specialists to your CPRS team. University medical centers and large teaching hospitals are often the best place to access this team of specialists.

Updated on: 08/22/18
Continue Reading:
CRPS/RSD Diagnosis