title: Distinct quantitative sensory testing profiles in nonspecific chronic back pain subjects with and without psychological trauma.
abstract: Psychological trauma is associated with an increased risk for chronification of nonspecific chronic back pain (nsCLBP) independent of posttraumatic stress disorder (PTSD). However, the mechanisms underlying the role of psychological trauma in nsCLBP are less clear than in PTSD. Therefore, this study considered whether psychological trauma exposure (TE) is accompanied by specific alterations in pain perception. The study included 56 participants with nsCLBP and TE (nsCLBP-TE), 93 participants with nsCLBP without TE (nsCLBP-W-TE), and 31 pain-free controls. All participants underwent a thorough clinical evaluation. The standardized quantitative sensory testing protocol of the "German Research Network on Neuropathic Pain" was used to obtain comprehensive profiles on somatosensory functions in painful (back) and non-painful areas (hand). The protocol consisted of thermal and mechanical detection as well as pain thresholds, vibration thresholds, and pain sensitivity to sharp and blunt mechanical stimuli. Psychological trauma was validated by structured clinical interview. Trauma-associated symptom severity, anxiety, and depressive symptomatology were assessed by self-report questionnaires. Differences in somatosensory function were seen only for pressure pain thresholds. Compared with controls, nsCLBP-TE revealed hyperalgesia generalized in space with lower thresholds in painful and non-painful areas, whereas nsCLBP-W-TE demonstrated localized alterations with decreased thresholds only in the pain-affected area of the back (P ≤ 0.006). Our findings suggest an augmented central pain processing in nsCLBP-TE (alterations in painful and non-painful areas), whereas nsCLBP-W-TE show only local changes (alterations only in the painful area) suggesting regional sensitization processes. This finding might explain why TE without PTSD is associated with an increased prevalence of chronic pain.
authors: Department of General Internal Medicine and Psychosomatics, Medical Hospital, University of Heidelberg, Heidelberg, Germany Department of Neurophysiology, Centre for Biomedicine and Medical Technology Mannheim (CBTM), University of Heidelberg, Heidelberg, Germany.
authors: Jonas
authors: J
authors: Tesarz
authors: Andreas
authors: A
authors: Gerhardt
authors: Sabine
authors: S
authors: Leisner
authors: Susanne
authors: S
authors: Janke
authors: Rolf-Detlef
authors: RD
authors: Treede
authors: Wolfgang
authors: W
authors: Eich
mesh_terms: D001416:Back Pain / Q000150:complications* / Q000175:diagnosis* / Q000523:psychology; D016022:Case-Control Studies; D059350:Chronic Pain; D005260:Female; D006801:Humans; D006930:Hyperalgesia / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D017288:Pain Threshold / Q000502:physiology*; D011312:Pressure; D011569:Psychiatric Status Rating Scales; D011581:Psychological Tests; D000067073:Psychological Trauma / Q000150:complications* / Q000175:diagnosis*; D011788:Quality of Life; D018709:Statistics, Nonparametric; D015599:Trauma Severity Indices; D014732:Vibration