A pilot study using Tissue Velocity Ultrasound Imaging (TVI) to assess muscle activity pattern in patients with chronic trapezius myalgia

Table 1 Univariate analysis of the measured variables.

	All (N = 24)		Controls		TM		Statistics
Group			(N = 11)		(N = 13)
Variables	Mean	Std	Mean	Std	Mean	Std	(p-values)
Velocity (cm/s)
Velocity Mean bpp	-0.08	0.06	-0.06	0.06	-0.09	0.06	0.361
Velocity Mean app	-0.08	0.08	-0.09	0.11	-0.08	0.05	0.569
Velocity diff mean	0.00	0.02	0.03	0.05	0.01	0.01	0.459
Velocity RMS bpp	0.13	0.07	0.11	0.06	0.14	0.08	0.494
Velocity RMS app	0.14	0.10	0.17	0.13	0.12	0.06	0.776
Velocity diff RMS	0.01	0.03	0.06	0.07	0.03	0.10	0.082
Strain rate (%/s)
Strain rate Mean bpp	0.22	0.09	0.23	0.09	0.21	0.08	0.865
Strain rate Mean app	0.27	0.13	0.31	0.14	0.23	0.10	0.186
Strain rate diff mean	0.05	0.04	0.08	0.05	0.02	0.19	0.150
Strain rate RMS bpp	0.28	0.10	0.29	0.11	0.28	0.10	0.910
Strain rate RMS app	0.32	0.16	0.38	0.18	0.27	0.12	0.167
Strain rate diff RMS	0.04	0.06	0.09	0.07	0.01	0.02	0.106
Strain (% compared with rest)
Strain Max bpp	64.10	22.51	62.35	22.83	65.59	23.06	0.691
Strain Max app	55.87	23.68	60.25	25.72	52.16	22.16	0.424
Strain diff max	8.24	1.17	2.11	2.89	13.42	0.90	0.424
Strain Mean bpp	33.08	11.97	32.32	10.15	33.72	13.71	0.608
Strain Mean app	30.95	13.42	33.68	14.66	28.63	12.38	0.459
Strain diff mean	2.13	1.45	1.36	4.51	5.09	1.32	0.331
Strain RMS bpp	39.37	12.46	39.20	12.57	39.52	12.88	0.820
Strain RMS app	34.26	17.03	39.41	17.39	29.90	16.10	0.167
Strain diff RMS	5.11	4.58	0.21	4.82	9.62	3.22	0.150

Comparisons are made between the Trapezius myalgia (TM) and a healthy control group without pain with respect to pain/exercise provocation. The following acronyms are used: before pain provocation (bpp), after pain provocation (app), Max = maximum value, RMS = Root mean square value, Diff = Difference between the value before, and after pain provocation (result is given in absolute value). The results of the statistical analyses between the two groups are given at the far right. The result shows no significant differences on groups level

ISSN: 1471-2474