Comparison Between the TSA2 and the Medoc Pathway in Assessing Thermal Leg Sensitivity
Date
2022-05
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Delaware
Abstract
Quantitative Sensory Testing (QST) is a method used to quantify somatosensory function in large
and small nerve fibers to detect sensory loss (i.e., hypoesthesia, hypoalgesia) or sensory gain (i.e.,
hyperesthesia, hyperalgesia, allodynia) that may be associated with acute and chronic pain. A set of
objective testing procedures that include both thermal and mechanical test stimuli are administered
based on a protocol. Thermal stimuli are administered with the gold standard Medoc Pathway, a
stationary and heavy piece of equipment, however, a new to the market portable Advanced
Thermosensory Stimulator (TSA2) is now available for testing with many of the same functions as
the pathway; however, it has not been tested in the lower extremity. The aim of this study is to
evaluate the agreement in thermal testing between the two machines. This is a repeated-measures two
group study with two test sessions one day apart (N=20). Thermal testing consisted of warm/cold
detection and heat/cold pain. Statistical analyses include paired t-test for mean differences, Pearson’s
correlation for agreement, intraclass correlation and coefficient alpha values, and Bland-Altman’s
plots for differences between the measurements. Mean age for participants was 32 years (SD=14.3)
and evenly split between men and women. The paired t-test revealed no significant differences
between the TSA2 and Medoc Pathway. Pearson correlations show strong correlations for thermal
pain on the TSA2 and Medoc Pathway. High alpha values were revealed on all tests conducted,
except for warm detection. Bland-Altman plots reveal agreeable data for cold detection, cold pain,
and warm pain. Warm detection displayed a distinct pattern where there were differences between the
Medoc Pathway and TSA2 when temperature rose, which might account for the low alpha value for
warm detection.
Description
Keywords
Quantitative sensory testing, Thermal testing, Thermosensory Stimulator (TSA2), Medoc Pathway