CRPS

 Complex regional pain syndrome (CRPS) describes an array of painful conditions that are characterised by a continuing (spontaneous and/ or evoked) limb pain that is seemingly disproportionate in time or degree to the usual course of any known trauma or other lesion. CRPS had been divided into three stages of progression based on the duration of symptoms. 

Stage I (Acute stage, 0-3 months): It is characterised primarily by pain/ sensory abnormalities (eg: hyperalgesia, allodynia), signs of vasomotor dysfunction and prominent edema.

Stage II (Dystrophic stage, 3-9 months): It is characterised by more marked pain/ sensory dysfunction, continues evidence of vasomotor dysfunction with development of significant motor/ trophic changes.

Stage III (Atrophic stage, 9-18 months): It is characterised by decreased pain/ sensory disturbance, continued vasomotor disturbance and markedly increased motor/ trophic changes.

Reference: Harrison’s principles of internal medicine, 21st edition