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What is complex regional pain syndrome (CRPS)?

Complex regional pain syndrome (CRPS) is a condition that causes severe pain which won't go away. It usually affects just one arm or leg and often follows an earlier injury to the limb. However, the body's reaction to the injury is much stronger than usual and may affect more of the limb than the original injury did.

Doctors sometimes make a distinction between two types of CRPS:

  • CRPS type 1 follows an injury such as a fracture or sprain but with no nerve damage – sometimes referred to as reflex sympathetic dystrophy (RSD) or Sudeck's syndrome
  • CRPS type 2 follows damage to a nerve in the limb – sometimes referred to as causalgia

Anyone can be affected by CRPS, including children. It most commonly affects the hand and wrist, foot and ankle, or knee, although sometimes the whole limb can be affected.

Should I see a doctor?

We would always recommend you see a doctor if you have pain that won't go away. CRPS is rare but it's important to get the right diagnosis so that appropriate treatments can begin. Research shows that treatment for CRPS is usually most effective when it’s started early on.


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