CRPS also called reflex sympathetic dystrophy syndrome, is a chronic pain condition in which high levels of nerve impulses are sent to an affected site. Experts believe that CRPS happens because of dysfunction in the central or peripheral nervous systems. CRPS usually affects an arm or a leg and typically develops after an injury, a surgery, a stroke or a heart attack. The pain is out of proportion to the severity of the initial injury.
CRPS is uncommon, and its cause isn’t clearly understood. Treatment is most effective when started early. In such cases, improvement and even remission are possible.
Signs and symptoms
- Continuous burning or throbbing pain, usually in your arm, leg, hand or foot
- Sensitivity to touch or cold
- Swelling of the painful area
- Changes in skin temperature — alternating between sweaty and cold
- Changes in skin color, ranging from white and blotchy to red or blue
- Changes in skin texture, which may become tender, thin or shiny in the affected area
- Changes in hair and nail growth
- Joint stiffness, swelling and damage
- Muscle spasms, tremors, weakness and loss (atrophy)
- Decreased ability to move the affected body part
Symptoms may change over time and vary from person to person. Pain, swelling, redness, noticeable changes in temperature and hypersensitivity (particularly to cold and touch) usually occur first.
Over time, the affected limb can become cold and pale. It may undergo skin and nail changes as well as muscle spasms and tightening. Once these changes occur, the condition is often irreversible.
CRPS occasionally may spread from its source to elsewhere in your body, such as the opposite limb.
In some people, signs and symptoms of CRPS go away on their own. In others, signs and symptoms may persist for months to years. Treatment is likely to be most effective when started early in the course of the illness.
Causes
The cause of CRPS isn’t completely understood. It’s thought to be caused by 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, with similar signs and symptoms, but different causes:
- Type 1 : Also known as reflex sympathetic dystrophy (RSD), this type occurs after an illness or injury that didn't directly damage the nerves in your affected limb. About 90% of people with CRPS have type 1.
- Type 2 : Once referred to as causalgia, this type has symptoms similar to those of type 1. But type 2 CRPS occurs after a distinct nerve injury.
Many cases of CRPS occur after a forceful trauma to an arm or a leg. This can include a crushing injury or a fracture.
Other major and minor traumas — such as surgery, heart attacks, infections and even sprained ankles — also can lead to CRPS.
It’s not well understood why these injuries can trigger CRPS. Not everyone who has such an injury will go on to develop CRPS. It might be due to a dysfunctional interaction between your central and peripheral nervous systems and inappropriate inflammatory responses.
How Is Complex Regional Pain Syndrome Treated?
Because there is no cure for CRPS, the goal of treatment is to relieve painful symptoms associated with the disorder. Therapies used include psychotherapy, physical therapy, and drug treatment, such as topical analgesics, narcotics, corticosteroids, osteoporosis medication, antidepressants, osteoporosis medicines, and antiseizure drugs.
Other treatments include:
- Sympathetic nerve blocks : Stellate ganglion block and Lumbar sympathetic nerve block are sympathetic blocks that are performed in the neck and low back respectively. These blocks can provide significant pain relief for some people.
- Surgical sympathectomy : This surgical technique involves destroying the nerves involved in CRPS. Some experts believe it has a favorable outcome, while others feel it makes CRPS worse. The technique should be considered only for people whose pain is dramatically but temporarily relieved by selective sympathetic blocks.
- Spinal cord stimulation : This technique, in which electrodes are placed next to the spinal cord, offers relief for many people with the condition.
