High-Frequency Impulse Therapy for Treatment of Chronic Back Pain: A Multicenter Randomized Controlled Pilot Study

Figures & data

Figure 1 HFIT Device.

Notes: HFIT device (left), HFIT device worn on model (right).

Abbreviation: HFIT, high-frequency impulse therapy.

Table 1 Baseline Characteristics

	Treatment (N=17)	Control (N=19)	Total (N=36)
Age (years)
Mean ± SD	54.0 ± 15.7	53.9 ± 16.2	53.9 ± 15.7
Min – Max	30.0–75.0	26.0–80.0	26.0–80.0
Sex – freq (%)
Male	3 (17.6%)	6 (31.6%)	9 (25.0%)
Female	13 (76.5%)	13 (68.4%)	26 (72.2%)
Race – freq (%)
White	13 (76.5%)	18 (94.7%)	31 (86.1%)
Non-white	4 (23.5%)	1 (5.3%)	5 (13.9%)
Weight (lbs)
Mean ± SD	186 ± 59.5	182 ± 39.0	184 ± 49.1
Length of pain (years)
Mean ± SD	12.2 ± 6.72	12.1 ± 10.0	12.1 ± 8.80
6MWT (meters)
Mean ± SD	337 ± 93.9	358 ± 63.1	348 ± 78.7
TUG (seconds)
Mean ± SD	13.2 ± 2.9	12.5 ± 1.8	12.9 ± 2.4
NRS Pain
Mean ± SD	7.5 ± 0.8	7.5 ± 1.0	7.5 ± 0.9
ODI
Mean ± SD	40.9 ± 10.2	43.1 ± 16.5	42.1 ± 13.8
PGIC
Mean ± SD	4.3 ± 0.8	4.2 ± 0.6	4.2 ± 0.7

Abbreviations: SD, standard deviation; 6MWT, Six Minute Walk Test; TUG, Timed Up and Go; NRS, Numerical Rating Scale; ODI, Oswestry Disability Index.

Figure 2 Flowchart.

Table 2 Assessment of Outcomes Over Time

Measure	Timepoint	Effect Size (95% CI)	p-value
6MWT	Day 1 After	0.03 (−0.30, 0.30)	p = 0.4370
	Week 1	0.21 (−0.11, 0.51)	p = 0.1036
	Week 2	0.33 (0.02, 0.61)	p = 0.0238*
	Week 3	0.32 (0.01, 0.59)	p = 0.0302*
	Week 4	0.31 (0.01, 0.60)	p = 0.0350*
TUG	Day 1 After	0.18 (0.15, 0.48)	p = 0.1479
	Week 1	0.28 (0.05, 0.56)	p = 0.0506
	Week 2	0.23 (0.11, 0.54)	p = 0.0908
	Week 3	0.30 (0.04, 0.57)	p = 0.0393*
	Week 4	0.22 (0.12, 0.49)	p = 0.1024
NRS Pain	Day 1 Before	0.003 (−0.32, 0.33)	p = 0.5129
	Day 1 After	0.22 (−0.53, 0.12)	p = 0.0971
	Week 1	0.26 (−0.52, 0.08)	p = 0.0635
	Week 2	0.34 (0.02, 0.58)	p = 0.0227*
	Week 3	0.11 (0.25, 0.47)	p = 0.2524
	Week 4	0.41 (0.10, 0.67)	p = 0.0071*
ODI	Week 1	0.12 (−0.22, 0.44)	p = 0.7607
	Week 2	0.02 (−0.36, 0.32)	p = 0.4623
	Week 3	0.09 (−0.26, 0.39)	p = 0.7016
	Week 4	0.22 (0.11, 0.49)	p = 0.1011
PGIC	Week 1	0.43 (0.12, 0.71)	p = 0.0057*
	Week 2	0.26 (−0.06, 0.55)	p = 0.0591
	Week 3	0.19 (−0.12, 0.49)	p = 0.1302
	Week 4	0.34 (0.04, 0.62)	p = 0.0223*

Notes: Mann–Whitney U-test of timepoint versus first timepoint. *p<0.05; Cohen’s metric for effect sizes: 0.2 - small, 0.5 - medium, 0.8 – large.

Abbreviations: 6MWT, Six Minute Walk Test; TUG, Timed Up and Go; NRS, Numerical Rating Scale; ODI, Oswestry Disability Index; PGIC, Patient Global Impression of Change.

Figure 3 Longitudinal mean scores for outcomes.

Notes: (A) 6MWT, (B) TUG, (C) NRS Pain, (D) ODI, (E) PGIC, (F) Device Usage; Error bars show standard errors.

Abbreviations: 6MWT, Six Minute Walk Test; TUG, Timed Up and Go; NRS, Numerical Rating Scale; ODI, Oswestry Disability Index; PGIC, Patient Global Impression of Change.