CRPS stands for Complex Regional Pain Syndrome. CRPS is a chronic neurological disease that can occur after injuries or surgical procedures to the upper or lower extremities. It is divided into Type I (soft tissue or bone injury) and Type II (nerve damage). Type I is often still known by the old name Morbus Sudeck.

The cause of CRPS is not fully understood to this day. After an injury, there is a dysregulation in the healing process, with inflammatory and neurogenic processes occurring, which cause various symptoms.

The symptoms are very diverse and can manifest far away from the injury site, which makes a corresponding diagnosis difficult. Typical symptoms are swelling, burning or stabbing rest pain, overheating or hypothermia, sensory disturbances with hypersensitivity, discoloration, and restrictions in mobility.