Quantitative sensory testing in the German Research Network on Neuropathic Pain (DFNS): Reference data for the trunk and application in patients with chronic postherpetic neuralgia

Abstract

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.

Assessment and manifestation of central sensitisation across different chronic pain conditions

“…A given assessment from a patient can then be compared with controls in the database using Z-scores to judge if an individual patient has a sensory abnormality (Rolke et al, 2006;Pfau et al, 2014).…”

Pre-surgery physiotherapy and pain thresholds in patients with degenerative lumbar spine disorders

“…When CPT in reference data had the broad normal range 32-0°C in most age groups (128,129), that difference in degrees at end-points had minor influence on the result.…”

“…In paper I the data from the participants' somatosensory profiles were compared with reference data obtained from healthy subjects from studies by the German Research Network on Neuropathic Pain (DFNS) (128,129). In order to do the comparisons, all QST data were standardized by Z-transformation, in which each QST value is matched for age and gender in the reference values (89).…”

Effects of cold stimulation on cardiac-vagal activation: Randomized controlled trial with healthy participants (Preprint)

“…Methods for HR reduction are equally of interest to athletes who need to speed up their return to homeostasis after physical exertion e.g [22,26,37]. Various scientific disciplines, e.g.…”

“…Cold temperatures were determined by corroborating indexes from pain studies e.g. [26] and studies on post exercise recovery experiments using CWFI e.g. [25,37].…”