Correlation Between Skin Temperature Over Myofascial Trigger Points in the Upper Trapezius Muscle and Range of Motion, Electromyographic Activity, and Pain in Chronic Neck Pain Patients

Abstract

ObjectiveThe purpose of this study was to assess the correlation between skin temperature over a myofascial trigger point in the upper trapezius muscle and range of motion of the cervical spine, electromyographic activity, and pain in patients with chronic neck pain. MethodsThis is a single-blind cross-sectional study. Forty participants of both sexes, aged 18 to 45 years, with chronic neck pain and myofascial trigger points in the upper trapezius muscle were included in the study. The participants were assessed using the Numeric Rating Scale, the Neck Disability Index, infrared thermography, algometry, fleximetry, and electromyographic activity. ResultsA positive association was observed between skin temperature to the right with the range of motion of cervical flexion (r = 0.322, P = .043), the median frequency of isometrics to the right (r = 0.341, P = .032), and the median frequency of rest to the left (rs = 0.427, P = .006); as were a negative association between skin temperature to the right and the root mean square of rest to the right (rs = -0.447, P = .004), and a positive association of skin temperature to the left with the median frequency of isometrics to the right (r = 0.365, P = .020), and the median frequency of rest to the left (rs = 0.573, P < .001). ConclusionPatients with chronic neck pain who had reduction of skin temperature over myofascial trigger points in the upper trapezius muscle had reduced cervical range of motion for flexion, reduced median frequency at rest and during isometric contraction, and increased root mean square at rest.