Ultrasound muscle backscatter reduction rate at 20° beam steering accurately distinguished hypertonic from normal muscles in young (AUC 0.89) and middle-aged (AUC 0.80) adults (p<0.01).
Observational (n=125)
Do ultrasound backscatter parameters accurately assess upper trapezius muscle hypertonicity in adults?
Ultrasound backscatter reduction rate at 20° beam steering can reliably distinguish hypertonic from normal upper trapezius muscles in young and middle-aged adults.
Effect estimate: AUC 0.89 (young), 0.80 (middle-aged)
p-value: p=<0.01
Objectives To investigate the feasibility of ultrasound backscatter parameters in assessing upper trapezius muscle (UTM) hypertonicity. Methods We prospectively measured pixel intensity on B-mode ultrasound images of UTM and adjacent subcutaneous tissue (SUBC) using Image J histogram, and calculated backscatter reduction rate and anisotropy following beam steering at 5°, 10°, 15°, and 20° from 0°. We analyzed differences in backscatter parameters of UTM and SUBC between three age groups using one-way analysis of variance (ANOVA), between normal and hypertonic UTMs using paired t-test, diagnostic performances of backscatter parameters for determining ≥ mild hypertonic UTM using area under receiver operating characteristic curve (AUC), and inter- and intra-observer reliability in measuring pixel intensity using intraclass correlation coefficient (ICC) and Blant-Altman analysis. Results We recruited 125 adult subjects (39 with normal UTM, 86 with hypertonic UTM) in three age groups (young age: 18-44y; middle age: 45-64y; old age: ≥65y). Differences in backscatter parameters between normal and hypertonic UTM were significant in young and middle-aged groups (p0.05). AUC of muscle backscatter reduction rate at beam steering 20° for determining ≥ mild hypertonicity was 0.89, 0.80, and 0.64 in young, middle-aged, and old-aged participants, respectively. ICCs of observer reliability for measuring pixel intensity were > 0.80. Conclusions The muscle backscatter reduction rate at beam steering 20° can distinguish hypertonic muscles from normal muscles in young and middle-aged with good intra- and inter-operator reliability. Muscle backscatter reduction rate in adults decreases with aging and the occurrence of hypertonicity.
Gao et al. (Fri,) conducted a observational in Upper trapezius muscle hypertonicity (n=125). Ultrasound backscatter parameters vs. Normal upper trapezius muscle was evaluated on Diagnostic performance for determining ≥ mild hypertonic upper trapezius muscle (AUC 0.89 (young), 0.80 (middle-aged), p=<0.01). Ultrasound muscle backscatter reduction rate at 20° beam steering accurately distinguished hypertonic from normal muscles in young (AUC 0.89) and middle-aged (AUC 0.80) adults (p<0.01).