Complex regional pain syndrome

Complex regional pain syndrome (CRPS), formerly known as reflex sympathetic dystrophy (RSD), is a chronic pain condition characterized by severe, persistent pain that is often out of proportion to the severity of the initial injury. The syndrome is believed to be caused by damage to, or malfunction of, the peripheral and central nervous systems.

Symptoms

The primary symptom of CRPS is prolonged severe pain that may be constant. It has been described as "burning," "pins and needles" sensation, or as if someone were squeezing the affected limb. The pain may spread to the entire arm or leg, even though the initial injury might have been only to a finger or toe. In some cases, pain can even travel to the opposite extremity. There is often increased sensitivity in the affected area, known as allodynia, in which normal contact with the skin is experienced as very painful.

Causes

The exact cause of CRPS is unknown, but it is thought to result from an injury to or an abnormality of the peripheral and central nervous systems. CRPS typically occurs as a result of a trauma or an injury. CRPS occurs in two types, CRPS-I and CRPS-II, with the same symptoms but different causes. CRPS-I (formerly known as reflex sympathetic dystrophy syndrome) can follow an illness or injury that didn't directly damage the nerves in the affected limb. About 90 percent of people with CRPS have CRPS-I. CRPS-II (previously called causalgia) follows a distinct nerve injury. Many cases of CRPS result from forceful trauma to an arm or a leg, such as a crush injury, fracture or amputation.

Treatment

While there is no cure for CRPS, treatment can be effective if started early. In such cases, improvement and even remission are possible. The goal of treatment is to relieve painful symptoms so that people can resume their normal lives. The following therapies are often used:

• Rehabilitation therapy: An exercise program to keep the painful limb or body part moving can improve blood flow and lessen the circulatory symptoms. Additionally, working with a physical therapist can help patients to improve the mobility and function of the affected region.
• Psychotherapy: CRPS and other painful and disabling conditions often are accompanied by mental health conditions, such as depression and PTSD. Psychotherapy can help patients to learn coping techniques and help them to adhere to their rehabilitation program.
• Medications: Several different classes of medication have been reported to be effective for CRPS, particularly when used early in the course of the disease.

See also

• Chronic pain
• Neuropathic pain
• Pain management