Introduction: Electric Quantitative Sensory Testing (eQST) studies have shown that central sensitization plays a key role in the maintenance [1] and development [2] of chronic pain. At present, the electrodes used for eQST measurements produce non-specific, deep stimulation of the skin and underlying structures. For eQST, however, it is deemed advantageous to more selectively stimulate cutaneous nociceptors [3]. Recently, the CutaStim has been developed to stimulate the epidermal skin more selectively during electric pain sensitivity measurements [4]. The present study aims to explore the performance of the CutaStim during eQST measurements.
Methods: CutaStim electrodes were produced according to large-scale production principles. The CutaStim realizations were then tested with chronic pain (CP, N=11) patients and healthy subjects (HC, N=18) at the Roessingh Rehabilitation Centre and compared to the results obtained with the Red Dot 2560 (conventionally used electrode, RD). Participants were measured two times, wherein the measurements were approximately one week apart from each other. The Medical Ethics Committee Twente approved all experimental procedures.
Results: The CS was found to have a lower test-retest reliability in the HC (0.134, 95% CI [-0.516 0.702]) and CP (0.454, 95% CI [-0.579 0.951]) groups as compared to the RD electrode (HC: 0.768, 95% CI [0.30 0.94], CP: 0.828, 95% CI [0.281 0.973]). At the retest, the pain threshold measured with the CutaStim was found to statistically lower with the CP as compared to the HC group. No differences in EPT between the HC and CP groups were established when measured with the RD electrode.
Conclusion: Overall, it can be concluded that the CutaStim did not perform as expected. A potential explanation for these results is that an eQST measurement with the CS does not result in an obvious transition from a non-nociceptive to a nociceptive stimulus, which is what defines the pain threshold. From this study, it is concluded that in the presently used setting, the CS is not an improvement for eQST measurements. More measurements should however still be performed to better interpret the findings. Future research should focus on acquiring this additional data and finding an explanation for the present results.
REFERENCES
[1] M. Curatolo, M. Müller, A. Ashraf, A. Y. Neziri, K. Streitberger, O. K. Anderson and L. Arendt-Nielsen, „Pain Hypersensitivity and Spinal Nociceptive Hypersensitivity in Chronic Pain,” Pain, vol. 156, nr. 11, pp. 2373-2382, 2015.
[2] A. Wright, P. Moss, K. Sloan, R. J. Beaver, J. B. Pedersen, G. Vehof, H. Borge, L. Maestroni and P. Cheong, „Abnormal Quantitative Sensory Testing is Associated With Persistent Pain One Year After TKA,” Clinical Orthopaedics and Related Research, vol. 473, nr. 1, pp. 246-254, 2015.
[3] C. D. Morch, K. Hennings and O. K. Anderson, „Estimating nerve excitation thresholds to cutaneous electrical stimulation by finite element modeling combined with a stochastic nerve fiber model,” Medical & Biological Engineering & Computing, vol. 49, nr. 4, pp. 385-395, 2011.
[4] R. ten Berge, „Development of the CutaStim electrode,” University of Twente, BSS, Enschede, 2014.
| Period | 25 Jan 2019 |
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| Event title | 7th Dutch Bio-Medical Engineering Conference, BME 2019 |
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| Event type | Conference |
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| Conference number | 7 |
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| Location | Egmond aan zee, NetherlandsShow on map |
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| Degree of Recognition | Regional |
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- Quantitative Sensory Testing
- Central Sensitization
- Chronic Pain