Reflex Sympathetic Dystrophy Syndrome (RSDS)

What Is It?

Reflex sympathetic dystrophy syndrome (RSDS) is a severe, painful and long-lasting condition that usually involves one arm or leg. This condition has been called many other names, including algodystrophy, causalgia, shoulder-hand syndrome, Sudeck's atrophy and transient osteoporosis. In 1995, the name was changed officially to complex regional pain syndrome, or CRPS, although this name change has not been accepted universally.

The problem in RSDS is severe, constant, burning pain in the affected arm or leg.

The condition can be triggered by damage to nerve fibers in tissue that was injured in some way, but the cause of this syndrome remains unknown. Experts believe that in RSDS, nerves become overly sensitive. Painful signals become more painful, and common stimuli such as light touch and temperature changes also are experienced as pain.

This condition usually starts after an injury or other event, such as trauma, a fracture, an infection, surgery, a Stroke or wearing a plaster cast. Often, the injury that triggers reflex sympathetic dystrophy syndrome is very mild compared with the pain that follows it. However, the condition also can follow more severe injury or paralysis. The pain often is not limited to the area that was injured. The earliest described cases were among Civil War soldiers in whom gunshot wounds that healed were followed over days to weeks by severe pain in arms or legs.

This condition can occur at any age and is relatively rare. It is most common in people between the ages of 40 and 60, but it is being diagnosed more frequently in children and adolescents. Researchers estimate that 12 percent to 21 percent of adults with paralysis on one side of the body and about 5 percent of adults with nerve injuries will develop reflex sympathetic dystrophy syndrome.

In children with RSDS, girls are affected about two to four times more often than boys.

Symptoms

Symptoms of RSDS can include:

• Intense pain, throbbing, burning and swelling, usually in the hand or foot
• Shiny, thin skin around the affected area
• Initially increased but later diminished hair over the affected area
• Brittle, thickened nails
• Dry and withered skin
• Skin that feels warmer or cooler than usual
• Skin that changes color
• Increased sweating

The condition can progress through three stages, although not everyone goes through every stage. In the earliest stage, days to weeks after an injury, the limb can become dry, hot, red and painful. Even the lightest touch or the slightest movement can cause excruciating pain. At this point, RSDS can be mistaken for , infection, or another disorder, and your doctor may not be able to identify the problem.