A new set of reference data on the trunk for male and female healthy subjects is presented and applied to patients with postherpetic neuralgia.
Age- and gender-matched reference values are essential for the clinical use of quantitative sensory testing (QST). To extend the standard test sites for QST—according to the German Research Network on Neuropathic Pain—to the trunk, we collected QST profiles on the back in 162 healthy subjects. Sensory profiles for standard test sites were within normal interlaboratory differences. QST revealed lower sensitivity on the upper back than the hand, and higher sensitivity on the lower back than the foot, but no systematic differences between these trunk sites. Age effects were significant for most parameters. Females exhibited lower pressure pain thresholds (PPT) than males, which was the only significant gender difference. Values outside the 95% confidence interval of healthy subjects (considered abnormal) required temperature changes of >3.3–8.2 °C for thermal detection. For cold pain thresholds, confidence intervals extended mostly beyond safety cutoffs, hence only relative reference data (left-right differences, hand-trunk differences) were sufficiently sensitive. For mechanical detection and pain thresholds, left-right differences were 1.5–2.3 times more sensitive than absolute reference data. The most sensitive parameter was PPT, where already side-to-side differences >35% were abnormal. Compared to trunk reference data, patients with postherpetic neuralgia exhibited thermal and tactile deficits and dynamic mechanical allodynia, mostly without reduced mechanical pain thresholds. This pattern deviates from other types of neuropathic pain. QST reference data for the trunk will also be useful for patients with postthoracotomy pain or chronic back pain.
aDepartment of Neurophysiology, Center for Biomedicine and Medical Technology Mannheim (CBTM), Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
bDepartment of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr University Bochum, Bochum, Germany
cDivision of Neurological Pain Research and Therapy, Department of Neurology, Universitaetsklinikum Schleswig-Holstein, Campus Kiel, Germany
dDepartment of Neurology, Technische Universität, München, Germany
eDepartment of Neurology, University Medical Centre, Johannes Gutenberg-University, Mainz, Germany
fDepartment of General Internal Medicine and Psychosomatics, University Hospital Heidelberg, Heidelberg, Germany
gDepartment of Biological and Clinical Psychology, Institute of Psychology, Friedrich Schiller University, Jena, Germany
hDepartment of Pain Medicine, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH Bochum, Ruhr University Bochum, Bochum, Germany
* Corresponding author. Address: Department of Neurophysiology, Center for Biomedicine and Medical Technology Mannheim (CBTM), Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Str. 13-17, Mannheim 68167, Germany. Tel.: +49 621 383 9926.
1 These authors contributed equally to this study.
2 DFNS steering committee.
Received 11 September 2013
Received in revised form 31 December 2013
Accepted 5 February 2014
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