Reflex Sympathetic Dystrophy
Complex regional pain syndrome (CRPS), formerly Reflex Sympathetic Dystrophy or Causalgia, is a chronic progressive disease characterized by severe pain, swelling, and changes in the skin. It often affects an arm or a leg and may spread to another part of the body and is associated with dysregulation of the autonomic nervous system resulting in multiple functional loss, impairment, and disability. Though treatment is often unsatisfactory, early multimodal therapy can cause dramatic improvement or remission of the syndrome in some patients. The International Association for the Study of Pain has proposed dividing CRPS into two types based on the presence of nerve lesion following the injury.
Causalgia
A burning pain often associated with trophic skin changes in the hand or foot, caused by peripheral nerve injury. It may be aggravated by the slightest stimuli or it may be intensified by the emotions. It usually begins several weeks after the initial injury and the pain is described as intense, with patients sometimes taking elaborate precautions to avoid any stimulus that they know could cause a flare-up of symptoms.
Phantom Limb Pain
A phantom limb is the sensation that an amputated or missing limb (even an organ, like the appendix) is still attached to the body and is moving appropriately with other body parts. Approximately 60 to 80% of individuals with an amputation experience phantom sensations in their amputated limb, and the majority of the sensations are painful. Phantom sensations may also occur after the removal of body parts other than the limbs, e.g. after amputation of the breast, extraction of a tooth (phantom tooth pain) or removal of an eye (phantom eye syndrome). The missing limb often feels shorter and may feel as if it is in a distorted and painful position. Occasionally, the pain can be made worse by stress, anxiety, and weather changes. Phantom limb pain is usually intermittent. The frequency and intensity of attacks usually declines with time.