Complex regional pain syndrome (CRPS) is a chronic pain condition that is as complex as it is rare. When a person sustains an injury, sometimes the nerves are damaged, causing the central and peripheral nervous systems to send and receive confusing or incorrect signals to the brain. The result is pain and swelling in the arms and/or legs. For 92% of patients, this pain may start in one arm or leg and then spread to others. This condition has been classified as one of the most painful chronic pain conditions, scoring 42 out of 50 on the McGill Pain Index. This makes complex regional pain syndrome more painful than childbirth or amputation. But, what is CRPS and who does it affect?

What is CRPS?

CRPS is a chronic pain condition that causes continuous throbbing or burning pain in a limb, along with other symptoms.

Lingering pain after a traumatic event or injury is generally regarded as uncommon and serious. One such form is a condition known as complex regional pain syndrome (CRPS). This condition is most frequently found in individuals who have sustained an injury, had surgery, a stroke, or heart attack but it affects a certain limb in a way that is uncharacteristic of the injury or surgery itself. When it does occur it is most commonly experienced in middle age and affects women more than men.

Even though it is frequently associated by trauma or injury the exact cause of this condition is not clear. Complex regional pain syndrome is not consistent and not every patient who suffers from the same injury will develop the condition. In spite of being rare, patients are encouraged to understand the early signs and symptoms so treatment can begin as quickly as possible.

You can find out more about this condition in the following video.

What are CRPS symptoms?

In complex regional pain syndrome, the body is reacting to nerve damage or trauma in an amplified way. Symptoms can be minor or severe and can sometimes resolve themselves or worsen over time for no apparent reason. In addition to pain and swelling, other symptoms of complex regional pain syndrome include:

  • Tight, shiny skin. The swelling of the arms and legs can cause skin to appear thin, tight, and shiny. This may eventually cause cracks to appear if the skin is not properly cared for.
  • Muscle spasms. Uncontrollable movement in the affected limb is present in most cases.
  • Sensitivity to touch. Even things like water and vibrations can be painful for patients with complex regional pain syndrome.
  • Variations in thermoregulation. Because the nerves are not able to consistently regulate body temperature, skin may feel hot or cold in response to abnormal, inconsistent blood flow. Skin may also appear blotchy or turn bright red or blue.
  • Bone issues. Bones in the affected limb mat soften and become weaker, and the patient may experience joint stiffness and decreased range of motion.

Symptoms that are seen less frequently include dizziness and fainting. Patients will also occasionally report problems with vision and osteoporosis.

Due to the rarity and complex nature of this condition, it is extremely important that at-risk individuals watch out for these signs and symptoms. If you have experienced a traumatic injury and notice one or more of these symptoms it is important that you talk to your doctor to find out if you might be affected by complex regional pain syndrome.


Early diagnosis and treatment is critical when it comes to complex regional pain syndrome. The two most common complications that result from the condition are atrophy and muscle tightening. When it is painful to move because of the irritation and inflammation in the nerves, many patients will avoid motion all together. This eventually leads to the weakening of the bones and muscles in this area of the body. With muscle tightening, the limb becomes contracted in a fixed positon. Both of these complications are difficult to reverse.

Stages of complex regional pain syndrome

Patients may move through several stages before being diagnosed with the condition. Stage one is when burning pain at the site of injury begins. Patients may also experience sweating and change in color of the limb due to fluctuations in thermoregulation. This stage can last for several weeks.

Pain increases, as does swelling, when a patient progress to stage two. Hair growth stops, and nails may also grow brittle and develop cracks and ridges. The joints stiffen, and muscles become weaker and atrophy.

Stage three brings about irreversible changes in skin and bones. Pain increases to a level that is unbearable, and may begin to involve not only the whole limb but also spread to the rest of the body. Movement is severely limited, and occasionally bones are moved around in the affected limb due to softening. The tendons that are responsible for moving the limb begin to contract, pulling the foot or hand towards the body.

Types of complex regional pain syndrome

Complex regional pain syndrome is usually divided into two types.

In CRPS-I, there is no obvious trauma or injury to the nerves. This indicates that the condition may have originated internally, or that the body has sustained an infection that may have caused damage. CRPS-II is originated from obvious injury or trauma. Because both types have the same symptoms and treatments, some researchers are not in agreement that this division is valid or that a division is necessary at all.

Regardless, 90% of patients have clear evidence of trauma or injury. These injuries can be fractures, sprains, strains, bruises, burns, or cuts. They can also occur as a result of being in a cast or undergoing surgery. While most people sustain a broken ankle or a huge bruise and then go on to recover without developing CRPS, some have a severe reaction to the injury. There is limited connection to genetic history as a cause of CRPS. However, those with autoimmune disorders or other inflammatory responses have a higher incidence of CRPS.

Those with CRPS have a high level of cytokines, inflammatory chemicals released in reaction to some stimulus (physical or chemical). The extreme response to injury is almost like the body’s defense mechanism to the injury.

Complex regional pain syndrome involves the small fibers in the nerves. It can cause blood vessels to open wide to leak fluid into the surrounding muscle and tissue. This response causes swelling, redness, and pain. When the small fibers cause constriction, blood vessels cut off the flow of blood and cause the affected limb to feel cold and become white or blue in tone. Those patients who have conditions that affect the blood vessels may be particularly susceptible to this response.

How can I get a CRPS diagnosis?

Patients who have nerve abnormalities in the small nerve fibers seem to develop this condition more frequently.

The ends of the small nerve fibers are densely packed and very sensitive. They contribute to inflammation and abnormalities in the blood. In extreme cases, these abnormal small peripheral nerves can trigger abnormalities within the larger central nervous system, which can lead to neurological issues in brain function.

There is not a single test that indicates complex regional pain syndrome. When a patient presents for diagnosis, it is usually due to an extreme painful reaction to a light stimulus. Doctors then rely on patient reporting and history as well as their own observation to begin initial diagnostics. Thermography and X-rays can be used, as well as sympathetic nerve blocks to see if nerve damage is the cause of pain.

What Is CRPS? (Complex Regional Pain Syndrome) |

What CRPS treatments are available?

It is possible to effectively treat complex regional pain syndrome and even send the condition into remission. Most patients see the best results with a combination of pharmaceutical treatment and therapy options.

CRPS medications

Multiple medications have been used to treat and reduce the symptoms of complex regional pain syndrome. They include:

  • Over-the-counter pain relievers
  • Antidepressant medications
  • Corticosteroids
  • Bone-loss medications
  • Sympathetic nerve-blocking medication
  • Intravenous ketamine

Once a diagnosis is reached, both types of CRPS are treated in the same manner. Anticonvulsant and anti-depressant drugs seem to work well to alleviate the pain. This may have to do with the way that these drugs work on the pain receptors in the brain. Anti-inflammatory drugs and corticosteroids are utilized to reduce swelling, and doctors may prescribe opioids in extreme cases.

In some cases, patients can be prescribed higher doses or opioid medications to control the symptoms, however these treatments are typically considered a last resort after all other methods of control fail. They must be taken with caution and under the care of your pain doctor.


Other therapies that are helpful for complex regional pain syndrome include:

  • Application of heat and ice to the affected area
  • Topical creams to reduce sensitivity, such as capsaicin or lidocaine
  • Physical therapy
  • Biofeedback
  • Cutting-edge DRG stimulation

Physical therapy and counseling have been proven to work well in conjunction with one another, possibly even more effectively than any other treatment. For children and adolescents, this approach has been shown to be very effective, with one study reporting an 88% success rate in long-term pain reduction. This is good news as it allows doctors to avoid prescription drugs for younger patients.

When recurrences of the condition do occur there are usually responsible triggers such as extreme cold or intense emotional stress. If you’ve been diagnosed with complex regional pain syndrome and have been treated effectively it is critical to watch for and avoid triggers in your life wherever possible.

DRG stimulation for CRPS

DRG stimulation is a cutting-edge treatment for severe cases of CRPS. You can find out more about this procedure in the following video.

How can I prevent CRPS?

There are ways to prevent the occurrence of complex regional pain syndrome after a traumatic injury. Studies have demonstrated that people who take additional vitamin C after a fracture of the wrist have a lower risk of developing complex regional pain syndrome than those who do not. Adding this additional supplement after an injury can cause no additional harm in most cases so it is worth the extra effort.

In the cases of complex regional pain syndrome brought on by a stroke, it has also been shown that individuals who move as early as possible after the incident have a lower risk of the condition as well.

Where can I find support?

Because living with a chronic pain condition, especially one that is unpredictable and unexplainable, can be difficult there are a variety of things we recommend to ensure that you can have as normal a life as possible. CRPS is a hidden condition and since no one else can understand the severity of the pain you are experiencing it can be frustrating, to say the least. If you are dealing with the effects of complex regional pain syndrome we highly recommend seeking out a support group either in your community or online to have an outlet to discuss the shared experience of the condition.

To help maintain your emotional and mental health we also encourage you to continue with as many normal daily activities as possible to maintain a sense of normalcy in your life. Recognize the value of rest and don’t push yourself too hard physically. Stay connected with friends and family. Find joy in your hobbies. Don’t be afraid to seek professional help to cope with the emotional side effects of this condition. Self-care is often the most important piece of the puzzle when it comes to living with the effects of complex regional pain syndrome.

Finally, getting professional care from a certified pain specialist is the best way to reduce pain associated with CRPS. To find a pain specialist in your area, click the button below. They’ll be able to help you learn more about what is CRPS and how you can find treatments that work.

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