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Complex regional pain syndrome in adults: Pathogenesis, clinical manifestations, and diagnosis

Salahadin Abdi, MD, PhD
Section Editor
Jeremy M Shefner, MD, PhD
Deputy Editor
John F Dashe, MD, PhD


Complex regional pain syndrome (CRPS) is a disorder of a body region, usually of the distal limbs, which is characterized by pain, swelling, limited range of motion, vasomotor instability, skin changes, and patchy bone demineralization. It frequently begins following a fracture, soft tissue injury, or surgery.

The etiology, pathophysiology, clinical manifestations, and diagnosis of CRPS in adults are reviewed here. Other aspects of CRPS in adults and children are presented separately. (See "Complex regional pain syndrome in adults: Prevention and management" and "Complex regional pain syndrome in children" and "Evaluation of chronic pain in adults".)


The consensus definition of CRPS is as follows [1]: "CRPS describes an array of 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. The pain is regional (not in a specific nerve territory or dermatome) and usually has a distal predominance of abnormal sensory, motor, sudomotor, vasomotor, and/or trophic findings. The syndrome shows variable progression over time."

There are many older alternative names for CRPS in the literature, including reflex sympathetic dystrophy, algodystrophy, causalgia, Sudeck atrophy, transient osteoporosis, and acute atrophy of bone. Upper extremity involvement following stroke or myocardial infarction was sometimes referred to as the "shoulder-hand syndrome." In the modern era, these disorders are grouped under the single heading of complex regional pain syndrome (CRPS) [2].

Two subtypes of CRPS have been recognized [1,2]:

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Literature review current through: Dec 2017. | This topic last updated: Mar 23, 2017.
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