Low-Intensity Continuous Ultrasound for the Symptomatic Treatment of Upper Shoulder and Neck Pain: A Randomized, Double-Blind Placebo-Controlled Clinical Trial

Figures & data

Table 1 Patient Demographics

Patient Demographic Data
Variable	Active Ultrasound	Placebo Ultrasound	P-value
N	25	8
Sex (M/F)	9/16	3/5	0.999
Age, years	34.2 ± 13.9	30.3 ± 10.9	0.415
Height	169.8 ± 12.1	169.1 ± 9.7	0.869
Weight	75.1 ± 13.1	72.2 ± 22.4	0.737

Figure 1 The study schematic. Patients were enrolled and evaluated for baseline pain scores on day one of the studies. Two- and four-week follow-ups were included to evaluate compliance.

Figure 2 Wearable long duration ultrasound device (SAM^®, ZetrOZ Systems LLC, Trumbull, CT) bilateral placement. If patients were experiencing bilateral trigger points, a transducer was placed on each side over the trigger point. If the patient experienced unilateral trigger points, only one transducer was used. The transducer was placed over the most painful trigger point if the patient was experiencing multiple trigger points on one side.

Table 2 Primary Outcomes. The Pain Reported at Baseline and Weekly Averages. Change in Pain from Baseline and Comparison Between Groups Evaluated Using Independent t-Tests

Pain Diary Data (NRS)
Time	Active	Placebo	Between Group Mean 95% CI	P-value
Baseline	5.60 ±1.58	5.44 ±1.95	0.163 (−1.22 to 1.55)	0.81
Week 1	3.54 ±1.64	4.58 ±2.20	−1.03 (−1.65 to −0.42)	0.001
Week 2	3.26 ±1.58	4.74 ±2.39	−1.48 (−2.12 to −0.84)	<0.001
Week 3	3.09 ±1.54	3.92 ±2.10	−0.827 (−1.46 to −0.19)	0.011
Week 4	2.98 ±1.62	3.86 ±2.30	−0.87 (−1.64 to −0.106)	0.026
NRS mean change from baseline 95% CI
Week 1	−2.05 ±1.64	−0.860 ±2.21	−1.20 (−1.76 to −0.631)	0.001
	−2.76 to −1.35	−2.53 to 0.81
	p<0.001	p=0.306
Week 2	−2.34 ±1.59	−0.693 ±2.38	−1.65 (−2.23 to −1.06)	<0.001
	−3.03 to −1.65	−2.49 to 1.11
	p<0.001	p=0.443
Week 3	−2.51 ±1.55	−1.52 ±2.11	−0.989 (−1.57 to −0.410)	<0.001
	−3.18 to −1.83	−3.14 to 0.110
	p<0.001	p=0.07
Week 4	−2.61 ±1.63	−1.58 ±2.30	−1.03 (−1.71 to −0.358)	0.003
	−3.34 to −1.90	−3.40 to 0.24
	p<0.001	p=0.087

Table 3 The Pain Reported Before, 30 Minutes into the Treatment, 2 Hours into Treatment, and Post-Treatment (4 Hours). Change in Pain from Pre-Treatment and Comparison Between Groups Evaluated Using Independent t-Tests

Pain Diary Data (NRS)
Timepoint	Active	Placebo	Mean 95% CI	P-value
Pre-treatment	5.40 (±1.50)	5.22 (±2.14)	0.18 (−0.133 to 0.483)	0.26
0.5 hours	4.99 (±1.39)	4.98 (±2.13)	0.01 (−0.292 to 0.299)	0.98
2 hours	4.04 (±1.45)	4.61 (±2.08)	−0.57 (−0.865 to −0.265)	<0.001
4 hours	3.24 (±1.61)	4.34 (±2.26)	−1.10 (−1.42 to −0.764)	<0.001
NRS mean change from pre-treatment 95% CI
0.5 hours	−0.416 ±0.724	−0.237 ±0.761	−0.179 (−0.416 to −0.237)	0.008
	−0.599 to −0.218	−0.713 to 0.239
	p<0.001	p=0.328
2 hours	−1.36 ±1.14	−0.615 ±0.962	−0.747 (−1.362 to −0.615)	<0.001
	−1.55 to −1.16	−1.09 to −0.145
	p<0.001	p=0.01
4 hours	−2.16 ±1.56	−0.885 ±0.928	−1.28 (−2.16 to −0.885)	<0.001
	−2.36 to −1.95	−1.37 to −0.394
	p<0.001	p<0.001

Table 4 The Pain Reported Before, 30 Minutes into the Treatment, 2 Hours into Treatment and Post-Treatment (4 Hours). Change in Pain from Pre-Treatment and Comparison Between Groups Evaluated Using Independent t-Tests

Global Rating of Change
Time	Active	n	Placebo	n	Mean 95% CI	P-value
Week 1	2.35 ±1.96	131	0.76 ±1.89	41	1.59 (0.903 to 2.28)	<0.001
Week 2	2.84 ±2.01	117	0.53 ±2.44	43	2.31 (1.56 to 3.06)	<0.001
Week 3	3.21 ±2.45)	107	0.36 ±1.99	45	2.85 (2.03 to 3.67)	<0.001
Week 4	3.09 ±2.37)	96	0.14 ±1.93	35	2.95 (2.07 to 3.83)	<0.001
Overall	2.84 ±2.21	451	0.46 ±2.08	164	2.38 (1.99 to 2.77)	<0.001