Both syndromes are also characterized by autonomic dysfunction, which presents with temperature changes (usually localized, but can be global), cyanosis, and/or edema.The patient may also experience localized swelling; extreme sensitivity to nonpainful stimuli such as wind, water, noise, and vibrations; extreme sensitivity to touch (by themselves, other people, and even light clothing or bedding/blankets); abnormally increased sweating (or absent sweating); changes in skin temperature (alternating between overly warm and cold); changes in skin colouring (from white and mottled to bright red or reddish-violet); changes in skin texture (waxy, shiny, thin, tight skin); softening and thinning of bones; joint tenderness or stiffness; changes in nails and hair (delayed or increased growth, brittle nails/hair that easily break); muscle spasms; muscle loss (atrophy); tremors; dystonia; allodynia; hyperalgesia; and decreased/restricted ability and painful movement of affected body part. Drop attacks (falls), almost fainting, and fainting spells are infrequently reported, as are visual problems.The symptoms of CRPS vary in severity and duration. Since CRPS is a systemic problem, potentially any organ can be affected. Symptoms may change over time, and they can vary from person to person. The more dynamic symptoms, especially vascular aspects (edema, temperature) and location of pain, can change numerous times a day.Previously, CRPS was considered to have three stages however more recent studies suggest people affected by CRPS do not progress through sequential stages and the staging system is no longer in wide use. Growing evidence instead points towards distinct sub-types of CRPS. Cause
Complex regional pain syndrome is uncommon, and its cause is not clearly understood.
Complex regional pain syndrome (CRPS) is any of several painful conditions that are characterized by a continuing (spontaneous and/or evoked) regional pain that is seemingly disproportionate in time or degree to the usual course of any known trauma or other lesion. Usually starting in a limb, it manifests as extreme pain, swelling, limited range of motion, and changes to the skin and bones. It may initially affect one limb and then spread throughout the body; 35% of affected people report symptoms throughout their whole bodies. Two types exist: reflex sympathetic dystrophy (RSD) and causalgia. Having both types is possible. Classification
The classification system in use by the International Association for the Study of Pain (IASP) divides CRPS into two types. It is recognised that people may exhibit both types of CRPS. Signs and symptoms
Clinical features of CRPS have been found to be inflammation resulting from the release of certain proinflammatory chemical signals from the nerves, sensitized nerve receptors that send pain signals to the brain, dysfunction of the local blood vessels ability to constrict and dilate appropriately, and maladaptive neuroplasticity.The signs and symptoms of CRPS usually manifest near the injury site. The most common symptoms are extreme pain, including burning, stabbing, grinding, and throbbing. The pain is out of proportion to the severity of the initial injury. Moving or touching the limb is often intolerable. With diagnosis of either CRPS types I or II, patients may develop burning pain and allodynia.