Complex regional pain syndrome: observations on diagnosis, treatment and definition of a new subgroup.

Several definitions and sets of diagnostic criteria of complex regional pain syndrome have been proposed, but to date none has been accepted completely. This article presents a specific subtype of the disease, called 'chronic, refractory complex regional pain syndrome' which is extremely severe, disabling and resistant to treatment. It also emphasizes difficulties with diagnosing complex regional pain syndrome because of its variable clinical presentation and diagnostic criteria being insufficiently precise. The necessity to distinguish between criteria for clinical use and for scientific purposes is suggested with a proposal of practical guideline for diagnosing acute complex regional pain syndrome. A review of treatments for complex regional pain syndrome is presented, with opinion on their effectiveness: good in an early stage, less well in chronic and generally poor in the chronic, refractory subtype.