Prevalence of chronic pain after traumatic spinal cord injury: a systematic review

Published studies have reported widely divergent estimates of the prevalence of chronic pain among individuals with (traumatic) spinal cord injury (SCI). To develop an estimate based on a synthesis of the research, we used searches of MEDLINE, CINAHL, PsycINFO, and other bibliographic databases and an ancestor search to identify articles published since 1966 in any language that reported a pain prevalence rate for at least 30 subjects with certain or likely traumatic SCI. Data on sample makeup, study quality indicators, and pain prevalence were abstracted independently by two researchers. A total of 42 studies reported pain prevalence rates that ranged from 26% to 96%, with a fairly even spread between these extremes. The reported rate did not appear to be related to study quality. Pain prevalence in the combined samples did not appreciably differ between males and females, those with complete versus incomplete SCI, and those with paraplegia versus tetraplegia. We conclude that too much heterogeneity was present in the reports to calculate a post-SCI pain prevalence rate using meta-analytic methods. Further research is needed to determine whether rates are related to sample makeup (e.g., average subject age), research methods used (e.g., telephone interview vs self-report instruments), or even the definition of "chronic" pain.