What Is Complex Regional Pain Syndrome (CRPS)?
Learn more about this painful nerve problem that can cause limited use of the injured area.
Complex regional pain syndrome (CRPS) is a rare disorder of the sympathetic nervous system. It used to be called reflex sympathetic dystrophy (RSD). It causes chronic severe burning pain in the arms, fingers, palm of hand, shoulder, or legs. If not treated, the pain and weakness may lead to limited use of that body part.
There are 2 types. They only vary depending on if you have had nerve injury. Both have the same symptoms and outcome. They are:
CRPS type 1. This is if you have no past nerve injury.
CRPS type 2. This is if you have had nerve injury. CRPS type 2 used to be called causalgia.
What causes CRPS?
The cause of CRPS is not known. An injury may cause CRPS. It can be something minor, such as a sprain or a cut. Or it may be more severe, such as a bone break. Or it may be linked to a surgery, such as carpal tunnel release. As you’re healing, you may feel new, severe pain in the injured area. That pain may spread through the injured limb. Over time, other symptoms may appear.
Symptoms of CRPS
If you aren’t treated soon, the symptoms of CRPS can get worse or change over time. Below are symptoms that can occur in the body part that is affected.
Early-stage CRPS
Symptoms include:
Ongoing, severe, burning pain
Sensitive to touch (pain from physical contact that normally is not painful)
Swollen, blotchy, reddish, or purple skin
Stiff joints
Change in temperature of the body part
Abnormal sweating in the body part or nearby areas
Late-stage CRPS
Symptoms include:
Skin that appears shiny and thin
Loss of muscle strength
Changes in hair and nail growth
Ridges in skin look flatter than normal
Shrinking of the affected limb
Constant swelling of the foot or hand
Spreading to other limbs
Abnormal movements of the limb, such as poor coordination, tremor, and movements you can't control