Is One Trial Sufficient to Obtain Excellent Pressure Pain Threshold Reliability in the Low Back of Asymptomatic Individuals? A Test-Retest Study

Abstract

The assessment of pressure pain threshold (PPT) provides a quantitative value related to the mechanical sensitivity to pain of deep structures. Although excellent reliability of PPT has been reported in numerous anatomical locations, its absolute and relative reliability in the lower back region remains to be determined. Because of the high prevalence of low back pain in the general population and because low back pain is one of the leading causes of disability in industrialized countries, assessing pressure pain thresholds over the low back is particularly of interest. The purpose of this study study was (1) to evaluate the intra- and inter- absolute and relative reliability of PPT within 14 locations covering the low back region of asymptomatic individuals and (2) to determine the number of trial required to ensure reliable PPT measurements. Fifteen asymptomatic subjects were included in this study. PPTs were assessed among 14 anatomical locations in the low back region over two sessions separated by one hour interval. For the two sessions, three PPT assessments were performed on each location. Reliability was assessed computing intraclass correlation coefficients (ICC), standard error of measurement (SEM) and minimum detectable change (MDC) for all possible combinations between trials and sessions. Bland-Altman plots were also generated to assess potential bias in the dataset. Relative reliability for both intra- and inter- session was almost perfect with ICC ranged from 0.85 to 0.99. With respect to the intra-session, no statistical difference was reported for ICCs and SEM regardless of the conducted comparisons between trials. Conversely, for inter-session, ICCs and SEM values were significantly larger when two consecutive PPT measurements were used for data analysis. No significant difference was observed for the comparison between two consecutive measurements and three measurements. Excellent relative and absolute reliabilities were reported for both intra- and inter-session. Reliable measurements can be equally achieved when using the mean of two or three consecutive PPT measurements, as usually proposed in the literature, or with only the first one. Although reliability was almost perfect regardless of the conducted comparison between PPT assessments, our results suggest using two consecutive measurements to obtain higher short term absolute reliability.

Preclinical Signs of a Temporomandibular Disorder in Female Patients With Episodic Cervicogenic Headache Versus Asymptomatic Controls: A Cross‐Sectional Study

“…A trial was performed on the right arm before actually starting. Measurements were executed twice (intratester intraclass correlation coefficient .86‐.99) in a standardized order to avoid temporal summation: (1) left temporalis (posterior, anterior, central), (2) left tibialis anterior, (3) right tibialis anterior, and (4) right temporalis (posterior, anterior, central) . Averages of two measurements on each point were calculated and used for further analysis.…”

Trunk kinematics and low back pain during pruning among vineyard workers—A field study at the Chateau Larose-Trintaudon

“…Pressure pain sensitivity of the lower back region was assessed by measuring PPT over 14 anatomical locations in the low back region (Fig 2) of the vineyard-workers [33,34]. For the analysis, the 7 anatomical locations placed to the left side of the spinal processes have been grouped as P left , the 7 anatomical locations placed to the right side of the spinal processes have been grouped as P right and the 14 locations placed to the left of the spinal processes have been grouped as P all .…”

“…The examiner measured PPT a constant slope of 30 kPa/s, 3 times on each anatomical location. The mean of 3 PPT measurements of all 14 locations was used for data analysis [33,34,39]. PPT were collected during one session lasting approx.…”

“…Then, a sensitivity analysis using a median split to equally separate into 2 groups our sample of vineyard-workers [33,34,42,43] was performed for all cut-off angle to assess whether LBP intensity or pressure pain sensitivity was different between vineyard-workers below or above the median split. Finally, scatter plots were generated to assess the relationship between the combined duration of forward bending and trunk rotation with LBP intensity and pressure pain sensitivity.…”

“…Such analysis can be complemented by measurements of pressure pain thresholds over the low back. Consequently, assessing pressure pain sensitivity over locations of the low back offers an interesting and reliable [33,34] opportunity to investigate and visualize the associations of trunk forward bending, trunk rotation and pain sensitivity.…”