Complex regional pain syndrome (CRPS) is a condition characterized by pain lasting for a minimum of six months.
In most cases of complex regional pain syndrome, a single limb is affected. An injury often triggers the pain. There are two types complex regional pain syndrome and the symptoms are similar. The types include:
- Type 1: This happens following an injury or illness that did not directly cause nerve damage in the affected limb. Also referred to as reflex sympathetic dystrophy syndrome, this type affects about 90 percent of people with CRPS.
- Type 2: This type happens after a distinct nerve injury. It may also be called causalgia.
The cause of this condition is not completely understood. Experts believe that central or peripheral nervous system abnormalities may play a role. An injury might also trigger this condition. In most cases, complex regional pain syndrome develops after an injury or trauma.
The symptoms tend to vary greatly and can change over time. It is possible for the condition to spread elsewhere in the body. The symptoms may include:
- Throbbing and burning pain that is continuous
- Swelling in the painful area
- Skin color changes, ranging from blue or red to white and mottled
- Nail and hair growth changes
- Muscle spasms, weakness, tremors and loss
- Sensitivity to cold and touch
- Skin temperature changes that alternate between cold and sweaty
- Skin texture changes, such as thinning, tenderness, and shininess
- Joint swelling, stiffness, and damage
- A reduction in the ability to move the affected limb
It is possible for patients to experience symptoms that are more disabling if they do not seek prompt treatment. Muscle contractures are possible. This can cause the fingers, toes, feet or hands to contract into a fixed position. Loss of mobility may cause bones, muscles, and skin to weaken and deteriorate.
There is not a specific test doctors can use to definitively diagnose this condition. Instead, they might perform some diagnostic testing along with a physical exam to diagnose a patient with CRPS. The following tests might be done:
- Bone scan to look for bone changes
- Sympathetic nervous system testing to look for disturbances
- MRI to look for tissue changes
- X-rays to determine if the bones have mineral loss in the later stages
There are medications and therapies that can help to improve a patient’s symptoms. The following medications may be considered:
- Pain relievers to reduce discomfort
- Corticosteroids to improve mobility and decrease inflammation
- Sympathetic nerve-blocking drugs to block pain fibers
- Anticonvulsants and antidepressants to reduce pain
- Bone-loss medications to reduce bone loss
- Intravenous ketamine to alleviate pain
There are also therapy options to help improve a patient’s mobility and reduce their pain and other discomfort. Therapies can include:
- Physical therapy
- Transcutaneous electrical nerve stimulation
- Spinal cord stimulation
- Heat therapy
- Mirror therapy
The prognosis for this condition varies greatly. Some people go into spontaneous remission while others continue to have symptoms long-term.