Complex regional pain syndrome (CRPS), formerly known as reflex sympathetic dystrophy, describes chronic pain in a limb after some sort of injury. The pain is abnormal or excessive compared to how you would expect to respond to a typical injury. This pain can feel like burning, tingling, or pressure, and can be accompanied by swelling, discoloration, or changes in skin temperature. The most common causes of CRPS are fractures, sprains, burns, cuts, bruises, limb immobilization, surgery, or needle stick. It is still unknown why these injuries cause CRPS in some people but not others.
Anyone can get CRPS, but it is rare in the elderly and children under the age of 10. Complex regional pain syndrome is challenging to treat, but there are numerous treatment options for this chronic pain that are successful in helping patients reduce their pain and significantly improve their function. Nerve blocks involve injecting medicine under image guidance that block nerves that carry pain signals from different parts of the body. Spinal cord stimulation and dorsal root ganglion stimulation help to modulate pain pathways by the delivery of small doses of electricity to the spinal cord. Level I evidence (i.e. the highest level of clinical evidence for treatments) exists for both spinal cord stimulation and dorsal root ganglion stimulation in their effectiveness in treating CRPS.