Central poststroke pain: A systematic review

Background Physical, psychological, and/or social impairment can result after a stroke and can be exacerbated by pain. One type of pain after stroke, central poststroke pain, is believed to be due to primary central nervous system mechanisms. Estimated prevalence of central poststroke pain ranges widely from 8% to 55% of stroke patients, suggesting a difficulty in reliably, accurately, and consistently identifying central poststroke pain. This may be due to the absence of a generally accepted definition. Aim We aimed to clarify the role of thalamic strokes and damage to the spinothalamic pathway in central poststroke pain patients. Also, we aimed to gain a current understanding of anatomic substrates, brain imaging, and treatment of central poststroke pain. Summary of review Two independent reviewers identified 10,144 publications. Based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, we extracted data from 23 papers and categorized the articles' aims into four sections: somatosensory deficits, pathway stimulation, clinical trials, and brain imaging. Conclusions Our systematic review suggests that damage to the spinothalamic pathway is associated with central poststroke pain and this link could provide insights into mechanisms and treatment. Moreover, historical connection of strokes in the thalamic region of the brain and central poststroke pain should be reevaluated as many studies noted that strokes in other regions of the brain have high occurrence of central poststroke pain as well.