Complex regional pain syndrome is a type of intense chronic pain. The pain is usually felt in the arms or legs, and sometimes in the hands or feet.

CRPS usually starts after an injury, but can also develop after surgery, a stroke, or a heart attack. Complex regional pain syndrome isn’t common, and doctors don’t know what causes it.

The pain is much worse than would be expected for the injury. It can get worse over time, and may spread to other parts of the body.

Common symptoms of complex regional pain syndrome are:

  • Intense burning or throbbing pain
  • Stiffness and swelling in the affected joints
  • Changes in skin temperature ranging from sweaty to cold
  • Changes in skin color and texture
  • Changes in growth of hair and nails
  • Sensitivity to cold or touch
  • Extreme skin sensitivity
  • Swelling and stiffness in the affected area
  • Muscle spasms and weakness
  • Decreased ability to move the affected body part