Complex Regional Pain Syndrome (CRPS I/II, Causalgia)
According to the National Health Service (NHS), pain associated with CRPS is typically caused by an injury and is usually confined to one limb, but can spread to other parts of the body. Pain symptoms include burning, stabbing or stinging, but may also include a tingling sensation and numbness. Many CRPS patients also report symptoms of hyperalgesia (extreme sensitivity to pain) and/or allodynia (experiencing pain from a very light touch). Unlike CRPS I, CRPS II/causalgia is a painful condition arising from damage to a peripheral nerve. That results in chronic pain, generally restricted to the innervation pattern of the damaged nerve (or nerves), and generally, in a hyperalgesic state.
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