Complex regional pain syndrome
Complex regional pain syndrome (CRPS) describes a rare condition characterized by chronic pain following an injury. The pain is disproportionate to the severity of the injury and involves additional symptoms.
- Presents with severe pain, autonomic, trophic, and motor abnormalities.
- Usually start after an injury (typically crush-type, of the upper or lower limb), amputation, ischemic event (stroke, MI), or cancer.
- The pathophysiology is poorly understood, but it is related to abnormal peripheral and central sensory sensitization, increased sympathetic activity, and the release of certain neuropeptides that contribute to local inflammation.
Classification
CRPS is classified into two types, based on the injured tissue:
- CRPS type I. Bones and soft tissues. Also known as algodystrophy (algo = pain, dystrophy = malnutrition), reflex sympathetic dystrophy, and Sudeck's atrophy.
- CRPS type II. Nerve tissue. Also known as causalgia.