Delineate the different stages of CRPS.
CRPS is usually described in three different stages.
· Stage 1: acute or hyperemic stage. This stage occurs within days to weeks of the initial injury and is signifi-cant for a predominance of severe burning or lancinating pain. It is notable for signs of sympathetic blockade; thus the area affected is red, warm, and dry. Hyperesthesia, an exaggerated response to stimuli, and allodynia, a painful response to non-painful stimuli, are prominent symp-toms of this stage. Treatments instituted during stage 1 have the best prognosis for a cure.
· Stage 2: dystrophic stage. This stage occurs weeks to months after the initial insult. The signs and symptoms of this stage are consistent with sympathetic hyperex-citability. The area involved is pale or cyanotic and cool. Burning pain associated with hyperesthesia and allody-nia is again very common. Although treatments in this stage can be successful, the longer the duration of the symptoms the poorer the prognosis.
· Stage 3: atrophic stage. This stage occurs months to years after the initial injury. Atrophy of the tissues in the involved area occurs because of prolonged vasoconstric-tion caused by increased sympathetic discharge over time. Burning and hyperesthesia become less prominent and trophic changes predominate. The skin in the area becomes smooth and glassy and the hair begins to fall out. The nails become brittle and the muscles atrophic. The bones in the area show a classic patchy demineral-ization on radiography known as Sudeck’s atrophy of the bone. The prognosis for pain relief and functionality is very poor at this point.
It is common for a patient not to experience all three stages of the syndrome. Stages may be skipped or the pro-gression may be halted with appropriate therapy.