Reflex sympathetic dystrophy (RSD), also called complex regional pain syndrome (CRPS), is a chronic, painful, and progressive neurological condition that affects the skin, muscles, joints, and bones. The syndrome usually develops in an injured limb, such as a broken leg, or following surgery. However, many cases of RSD involve only a minor injury, such as a sprain. And in some cases, no precipitating event can be identified.
RSD/CRPS is characterized by various degrees of burning pain, excessive sweating, swelling, and sensitivity to touch. Pain may begin in one area or limb and then spread to other limbs. In some cases, symptoms of RSD/CRPS diminish for a period of time and then reappear with a new injury.
Two types of RSD/CRPS have been defined:
- Type 1-without nerve injury
- Type 2 (formerly called causalgia)-with nerve injury
Incidence and Prevalence of RSD/CRPS
Millions of people in the United States may suffer from RSD/CRPS. This chronic pain syndrome affects both men and women, and also occurs in children. It can occur at any age, but usually affects people between the ages of 40 and 60 years.
The National Institute of Neurological Disorders and Strokes (NINDS) reports that 2–5% of peripheral nerve injury patients and 12–21% of patients with paralysis on one side of the body (hemiplegia) develop reflex sympathetic dystrophy as a complication. The Reflex Sympathetic Dystrophy Syndrome Association of America (RSDSA) reports that the condition develops after 1–2% of bone fractures.