What is chronic regional pain syndrome?

Complex regional: Pain syndrome is what i believe you are asking about. This is a chronic condition, but the letters crps stand for complex regional pain syndrome. This is a tough disease process which can occur after any nerve injury, stroke, injury, even a heart attack which accounts for almost 15%.It has been thought to be sympathetically driven, has three stages, and causes immense pain usually in a single limb.

NIH Definition: Complex regional pain syndrome (CRPS) is a chronic (lasting greater than six months) pain condition that most often affects one limb (arm, leg, hand, or foot) usually after an injury. CRPS is believed to be caused by damage to, or malfunction of, the peripheral and central nervous systems. CRPS 1 is without a confirmed nerve injury and CRPS 2 is when there is a confirmed associated nerve injury.