Complex regional pain syndrome (CRPS) is a condition that causes extreme pain to an individual, usually on one limb, such as one arm or one leg but it can also spread to the entire body. It has been named ‘complex’ because there is a lot about it that is still unknown. People who have CRPS often acquired the symptoms from an injury, but it can also develop after a surgery, stroke or heart attack. It is an uncommon form of chronic pain.
What are the symptoms of CRPS?
The main sign of CRPS is the intense pain experienced in the affected area of the body. This is often in the limbs, such as the arm or foot. Sometimes the pain remains localized in the limb, but other times it can spread throughout the body. What sets apart pain from CRPS is the intensity, whereby the pain is more intense than is supposed to be experienced from the injury. The pain should also last for a few months before it can be distinguished from normal pain due to the injury.
Most people with CRPS describe the pain as a throbbing or burning pain, similar to the pins and needles sensation. The pain is also continuous with some intermittent periods of less pain that may be exacerbated by physical or emotional stress. The signs and symptoms of CRPS vary from one person to the other and they also tend to change over time.
In some patients, the signs and symptoms of CRPS tend to get worse over time, spread to other body parts and the affected limb may also undergo changes like skin changes, color changes, hair and nail changes, etc. These changes are often irreversible. On the other hand, in some patients, CRPS signs and symptoms tend to resolve on their own.
As the person continues to suffer from CRPS, pain clinic specialists can diagnose other symptoms such as:
An increased sensitivity (allodynia) – the person’s skin can become so sensitive that even a light touch or change in temperature can cause pain,
- Changes in skin temperature – sometimes the skin surface can become very hot and other times very cold. The skin surface will also become sweaty or dry depending on temperature,
- Changes in skin color – the skin will often turn a bright red and other times even blue,
- Swelling of the area where the pain is located,
- Muscle weakness,
- Muscle spasms around the area of the injury,
- Muscle atrophy,
- Softening and thinning of bones especially in the most affected area,
- Tenderness of the joint and stiffness,
- Joint swelling,
- Changes in hair and nail growth,
- Difficulties walking and moving the affected part of the body, etc.
What causes CRPS?
The most common trigger for CRPS is trauma, which accounts for 90% of CRPS cases. However, there is still no explanation why some people develop CRPS while others don’t even though they may experience the same trauma. Other triggers include surgery and even a needle prick from an injection. One of the explanations for this is an overly excessive response to injury, similar to what you see in a person with allergies.
Another pain doctor’s theory for CRPS surrounds the involvement of nerve damage, seeing how the condition may develop to affect other parts of the body beyond where the injury occurred. The theory is backed by peripheral nerve damage seen in those suffering from CRPS. When the peripheral nerves are injured, it is possible for the injury to spread to the central nervous system, causing pain in other areas of the body.
Due to the damaged nerve, the blood vessels that had dilated to produce the inflammatory response are unable to constrict, and the muscles and tissues become deprived of oxygen and then start to become damaged. This is what causes the subsequent symptoms.
Diagnosis and treatment
Three phase bone scan can be done to confirm CRPS. A negative test does not rule out CRPS. Ultimately, the diagnosis is based on the signs and symptoms that the patient presents with. Once the diagnosis is made, treatment involves pain relief medications, physical therapy, and psychological support since there is no cure for CRPS.
Common medications used for the treatment of CRPS include over the counter painkillers, antidepressants, anticonvulsants, corticosteroids, bone loss medications, etc.