The effects of TENS,interferential stimulation,and combined interferential stimulation and pulsed ultrasound on patients with disc herniation-induced radicular pain

Abstract

BACKGROUND:

Electrotherapy is part of a physician’s toolbox for treating various musculoskeletal conditions, including radicular pain, but the preferred modality is yet unclear.

OBJECTIVE:

To compare the short-term efficacy of three electrotherapeutic modalities in relieving lumbar disc herniation (LDH)-induced radicular pain.

METHODS:

Fourteen patients with LDH-induced radicular pain attended a single session of electrotherapy, which included four 10-min consecutive treatments: transcutaneous electrical nerve stimulation (TENS), interferential (IF) stimulation, a combined treatment with pulsed ultrasound and IF current (CTPI), and a sham control. Treatments were randomized and the straight leg raise (SLR) degree was measured immediately before and after each treatment.

RESULTS:

Each of the three active modalities significantly improved the SLR score. The most prominent improvement was observed in the CTPI condition, followed by IF and, finally, TENS. The sham stimulation did not affect the SLR scores.

CONCLUSIONS:

A single session with either TENS, IF current or CTPI is sufficient to improve the range of motion and degree of radicular pain associated with LDH. CTPI appears to be the most effective modality of the three, possibly due to greater penetration efficiency of the induced current. The effects of a long-term treatment schedule are yet to be identified.

Keywords

Transcutaneous electric nerve stimulation straight leg raise interferential current combined pulsed ultrasound and interferential current disc herniation nerve root irritation

1. Background

Lumbar disc herniation (LDH) is the localized displacement of disc material, usually in L–S1, beyond the normal margins of the intervertebral disc space [1]. This condition is a major contributor to low-back pain (affecting around 9% of the population worldwide [2]) and is considered the most common cause of nerve-root irritation (NRI), which affects 1–5% of the population annually [3]. NRI typically causes nerve inflammation [4] which, upon movement of or tension on the nerve root, may induce radicular leg pain: a wide (7–9 cm) band of lancinating pain along the lower limb [5].

Patients with LDH-induced NRI are typically offered various conservative (i.e., nonsurgical) first-line treatments before surgery (e.g., discectomy) is considered [6]. One such conservative treatment, which is usually applied as part of a multimodal treatment program, is electrotherapy, namely, placing electrode pads on the skin to electrically stimulate deeper tissues [7]. While numerous studies support the use of electrotherapy for a wide variety of indications [7, 8, 9, 10, 11, 12], its efficacy in relieving NRI-induced pain is not entirely clear. Several (mostly methodological) reasons appear to account for this lack. First, when electrotherapy is examined as part of a multimodal treatment program (e.g., in [13, 14]), its unique contribution to pain relief cannot be isolated. Second, most previous studies employed either transcutaneous electrical nerve stimulation (TENS) [13, 15, 16, 17, 18, 19] or interferential (IF) current stimulation [14, 20], two of the most commonly used electrotherapeutic modalities [7, 21], while only a handful of studies examined other modalities [15, 18]. Third, most previous studies of electrotherapy in the context of LDH-induced radicular pain employed subjective measures of pain, such as a visual analog scale (VAS) or questionnaires [14, 15, 16, 17, 18, 19, 20], while only a few studies [13] used more objective measures of pain. Thus, taken together, still lacking are systematically comparative and controlled studies, which directly compare between the efficacies of various electrotherapeutic modalities by using more objective measures of radicular pain.

To fill these lacunae, the current study aimed to systematically compare the efficacies of widely used electrotherapeutic currents in instantaneously relieving LDH-induced radicular pain. We focused on three electrotherapeutic modalities: TENS, IF current, and a combined therapy with pulsed ultrasound and IF current (CTPI), a common modality in most electrostimulation devices which has shown some clinical utility in the context of fibromyalgia [8, 22, 23, 24]. Notably, CTPI has been demonstrated to penetrate deeper into the tissue than TENS and IF-induced currents [25]; as the NRI associated with LDH and radicular pain is a relatively deep pathology (usually located 3.7–4.4 cm deep within the tissue [26]), and the high penetration efficiency of CTPI may be especially beneficial for relieving LDH-induced radicular pain.

As a relatively reliable measure of the radicular pain and of the typical reduction in the range of motion associated with LDH, we used the straight leg raise (SLR) test, a simple-to-use, reliable and, at least to some degree, clinically relevant measure of the integrity and mobility of neuronal structures [27, 28, 29, 30]. Notably, this test is considered to have high intra- and inter-rater reliability (namely, 0.95–0.98 [31] and 0.67–0.97 [32], respectively) and is used by 97.9% of physiotherapists to assess pain in patients with LDH-induced radicular pain [21]. During the SLR test, the leg of the patient is raised passively by the experimenter, such that traction is exerted onto the sciatic nerve, lumbo-sacral nerve roots, and dura, thus moving the nerve roots through their intervertebral foramina for distances up to several millimeters [33]. The recorded SLR score is the degree of hip flexion required to elicit the recurrence of symptoms (mean detectable change has been reported to range between 1.50 ${}^{\circ}$ [31] and 5.7 ${}^{\circ}$ [34]), which is highly correlated with LDH pathology and is, therefore, suitable for evaluating LDH-induced radicular pain [28, 35, 36].

2. Methods

2.1 Participants

This study included 14 adult participants (eight males and six females; mean age 53.5 years, SD $=$ 8.2 years, range 41–69 years; Table 1), who were diagnosed, using MRI scans and clinical assessments, with a single-level LDH with NRI between L4 and S1. All participants demonstrated a positive SLR result [37] and reported radicular pain to the leg, for which they were treated at the pain clinic of Sheba Medical Center, Tel HaShomer (Ramat Gan, Israel). All participants were screened for typical electrotherapy contraindications [7] and for a history of traumatic brain injury or systemic diseases that may affect sensation.

Table 1
Selected demographic data, stimulation intensities (Stim; in mA) at each active stimulation condition, and the SLR scores (in degrees) before (pre) and after (post) applying each stimulation modality

Demographics				Sham		TENS			IF			CTPI
Name	Gender	Age	Pain years ${}^{1}$	Pre	Post	Stim	Pre	Post	Stim	Pre	Post	Stim	Pre	Post
AS	M	60	4	62	63	14	60	68	18	60	72	12	62	78
AB	F	49	3	53	57	45	50	70	37	50	75	23	53	85
FE	M	69	2	32	30	65	32	42	63	34	43	30	34	58
MA	M	45	1	55	59	8.5	55	70	9	57	76	11	55	83
BK	M	62	0.5	55	57	32	53	63	27	53	68	27	57	80
PM	F	53	0.7	36	35	17	33	41	20	35	45	26	35	47
SS	F	46	4	22	26	23	20	23	23	18	27	23	22	38
AA	M	59	3	33	30	17	32	40	14	30	47	16	32	50
SD	M	54	6	30	30	66	30	38	62	30	43	44	30	44
TA	M	42	1.5	32	34	27	33	37	30	32	38	17	32	40
SH	M	41	3	33	32	28	33	33	27	33	37	20	32	39
YB	F	61	2.5	17	19	11	15	22	9	15	26	16	17	40
RG	F	55	0.5	43	43	25	42	42	22	42	48	8	42	58
HR	F	53	12	30	32	35	35	50	51	30	40	35	35	65

Notes: ${}^{1}$ Number of years of suffering pain due to the reported LDH-induced NRI.

2.2 Study design

The participants were recruited by contacting doctors at the Sheba Medical Center Pain Clinic, who performed the initial screening and obtained the initial consent to participate in the study. Each candidate participant was then contacted by phone and briefed about this study, and those who agreed to participate were sent (by fax or e-mail) a written explanation and a copy of the informed consent form. Upon arrival at the Pain Clinic, the participants were briefed, signed the informed consent form, and completed a short demographic questionnaire. Shortly after the experimental session, all participants received a pre-scheduled epidural lumbar injection under x-ray at the Pain Clinic. The study complied with the Declaration of Helsinki and was approved by the Human Ethics Committee of Sheba Medical Center and Tel Aviv University.

The entire experimental session took place in a dedicated closed and quiet room at the Pain Clinic and lasted about 2 h in total. First, the participant was instructed to lie supine and the initial SLR score (SLR ${}_{\textit{pre}}$ ) was measured, as described below. Then, the participant was asked to lie prone and new adhesive stimulating surface electrodes were attached to the skin according to the planned modality (four conditions altogether, randomized across participants; see below). For each stimulation condition except Sham, the current applied through the stimulating electrodes was first increased in 2 mA increments until the sensation threshold was reached, and then it was increased further, using the same staircase method [38], until the participant indicated the beginning of perceiving a painful stimulus. This current was defined as the individual pain threshold of the participant, and the stimulating currents throughout the experiment (Table 1) were always induced at 90% of this threshold. In each condition, the active or Sham stimulation was applied for 10 min, after which the participant was again asked to lie supine to measure the post-treatment SLR score (SLR ${}_{\textit{post}}$ ). Following a 15-min washout period, the electrode configuration was modified according to the next pre-defined stimulation condition and the procedure was repeated until all four conditions were applied (Fig. 1).

Figure 1.

Experimental timeline. Prior to the experimental session (pre-session), the participants were screened by the Pain Clinic doctors for LDH-induced NRI (according to MRI scans and clinical evaluations) with radicular pain and a positive SLR response. On the day of the experiment, all participants were briefed and completed an informed consent form and a demographic questionnaire. Next, prior to applying each stimulation modality (pre-treatment), the SLR score was measured (SLRpre) by an observer blind to the conditions of the experiment and the pain threshold for the selected modality (except sham) was measured by the experimenter. During the subsequent treatment phase, the selected modality (TENS, IF, CTPI, or sham, randomized across participants) was applied for 10 min, after which (post-treatment) the SLR score was again measured (SLRpost) by the observer. Following a 15-min washout phase, the process (pre- to post-treatment, curved arrow) was repeated until all four conditions were tested.

2.3 SLR measurements

The SLR scores were recorded immediately before and immediately after the application of each of the four stimulation conditions, which yielded the $\Delta$ SLR score (i.e., SLR ${}_{\textit{post}}$ – SLR ${}_{\textit{pre}}$ , presented in degrees of maximum leg raise). The degree of maximum leg raise was measured with a Saunders digital inclinometer (The Saunders Group Inc., USA), which was attached to the thigh of the symptomatic leg using a custom-built device made of flexible dried leather and adjustable Velcro straps (Fig. 2A). The measurements on the inclinometer were read to the experimenter by an independent observer (usually the person accompanying the participant) who was blind to the applied stimulation condition. Each score reported below is the arithmetic average of three consecutive SLR tests performed at 1-min intervals. The variability between the three successive measurements at each time point was negligible (data not shown).

Figure 2.

(A) The inclinometer used in this study to measure the SLR score, attached to the thigh of the participant using a custom-built device made of flexible leather and Velcro straps (insert). (B–C) Electrode placement for TENS (A), IF (B), and CTPI (C). Circles indicate the average LDH level across participants.

2.4 Stimulation

The stimulation electrodes were either 5 $\times$ 9 cm (for the TENS, IF, and Sham conditions) or 7.5 $\times$ 13 cm (for the CTPI condition) adhesive pad electrodes (ValuTrode CF5090; Axelgaard, Fallbrook, CA, USA), coated with a MultiStick conducting hydrogel (Axelgaard). The electrode pads were placed on the skin at the height of the herniated disc (see below) and the wires were connected to a Sonopuls 491 electrotherapeutic stimulator (Enraf-Nonius, Rotterdam, The Netherlands). To maintain consistency across trials, the same stimulation frequencies (30 Hz; amplitude-modulated in the IF and CTPI conditions) and pulse durations (250 $\mu$ s, resulting in a 125 $\mu$ s phase duration) were used in all active stimulation conditions. These electrotherapeutic parameters were previously shown to be effective in reducing pain [38].

The TENS condition included the application of biphasic symmetrical currents through two electrode pads positioned dorsally on the paravertebral muscles, at the height of the herniated disc (Fig. 2B). One electrode pad was placed on each side of the spinous process (1 cm lateral to the spinous process), such that the middle of each pad was placed at the level of the herniated disc. The IF condition included the application of amplitude-modulated sinusoidal currents (4 kHz carrier frequency) through two pairs of electrode pads, positioned in the most commonly used IF configuration [7], in which each two adjacent electrode pads are positioned 2 cm apart, such that the herniated disc is directly between the four stimulating pads (Fig. 2C). The CTPI condition included the application of a pre-modulated IF current (4 kHz carrier frequency) through the ultrasound treatment head (5 cm ${}^{2}$ ), which was coated with an ultrasound coupling gel (Intelect Ultrasound Gel, Chattanooga Medical Supply Inc., Chattanooga TN, USA) and placed on the spinous process at the level of the herniated disc. The ultrasonic waves were delivered at 1.2 W/cm ${}^{2}$ on a 20% duty cycle with a 1 MHz frequency, and the cutaneous electrode pad (used to close the circuit) was placed on the abdomen at the same level of the ultrasound head (Fig. 2D). Finally, the Sham condition included the same electrode placement as in the IF condition (Fig. 2C), but without applying active currents.

2.5 Statistical analyses

A power analysis was conducted in Statistica (ver. 12) to indicate the appropriate sample size for this study, based on the results of a pilot experiment. This analysis indicated that, under the assumption that SLR differences between the four test conditions will exceed 3 ${}^{\circ}$ , 14 participants are required for a 0.05-level significance at 80% power. A similar number of participants was used in previous studies of the efficiency, reliability, and validity of various relevant tools (including SLR), e.g. [29, 39] and others.

Due to the relatively low sample size and non-normal distribution of our data, we used the related-samples Friedman’s two-way analysis of variance by rank (a non-parametric test) with the Benjamini-Hochberg correction for multiple testing (FDR $<$ 0.05). We compared (1) the SLR scores before and after the stimulation, for each treatment condition, and (2) the $\Delta$ SLR between the different test conditions. Significance level was set to 0.05 in all tests, and all analyses were conducted with SPSS version 25.

3. Results

Selected demographic data, the applied stimulation intensities in each condition, and the SLR scores before and after applying each stimulation are shown in Table 1. A Friedman’s non-parametric test indicated that, whereas the Sham condition did not significantly affect the SLR score ( $\chi$ 2 $=$ 1.333, $p=$ 0.248), all other conditions increased the SLR score significantly (comparing before vs. after: TENS: $\chi$ 2 $=$ 12.000, $p=$ 0.001; IF: $\chi$ 2 $=$ 14.000, $p<$ 0.001; CTPI: $\chi$ 2 $=$ 14.000, $p<$ 0.001; Fig. 3).

Figure 3.

SLR scores before and after applying each stimulation modality. Bars indicate mean $\pm$ SD. NS $=$ not significant, ${}^{**}p<$ 0.01, ${}^{***}p<$ 0.001 (pairwise comparisons using two-sided Friedman’s non-parametric test, $n=$ 14).

Comparing the $\Delta$ SLR scores between the different experimental conditions revealed that the improvement was the greatest in the CTPI condition, followed by IF, TENS and, finally, Sham stimulation (mean $\pm$ SD: 19.1 $\pm$ 7.8, 11.9 $\pm$ 5.7, 8.3 $\pm$ 5.7, and 1.0 $\pm$ 2.3, respectively, $p<$ 0.05 for all pairwise comparisons; Table 2, Fig. 4). These differences were not due to differences in stimulation intensity, which did not differ significantly between the three active stimulation conditions (TENS: 29.5 $\pm$ 18.1 mA, IF: 29.4 $\pm$ 17.8 mA, and CTPI: 22.0 $\pm$ 9.9 mA; $\chi^{2}=$ 3.64, $p=$ 0.162). Notably, in the CTPI group, six participants (43%) showed a robust improvement ( $>$ 20) and three participants (21%) showed a very robust improvement $($ >25).

Table 2

Multiple pairwise comparisons (two-sided Friedman’s non-parametric test with a Benjamini – Hochberg correction) of the $\Delta$ SLR scores between the different stimulation conditions

		TENS	IF	CTPI
Sham	Z	$-$ 1.90	$-$ 3.57	$-$ 5.93
	$p$	0.057	$<$ 0.0001	$<$ 0.0001
TENS	Z		1.68	4.03
	$p$		0.092	$<$ 0.0001
IF	Z			$-$ 2.34
	$p$			0.019

Figure 4.

$\Delta$ SLR scores for each of the four test conditions. The boxplots indicate the median (horizontal line), first and third quartiles (bottom and top box boundaries, respectively), and 5th and 95th percentiles (bottom and top whiskers, respectively). ${}^{*}p<$ 0.05, ${}^{***}p<$ 0.001 (two-sided Friedman’s non-parametric test, $n=$ 14).

4. Discussion

This study aimed to test and compare between the efficacies of three widely available electrotherapeutic modalities in improving LDH-induced radicular pain, as reflected by the SLR scores. We found that an active (but not sham) 10-min electrotherapeutic stimulation is sufficient to significantly improve SLR scores, a finding with both diagnostic and, possibly, clinical relevance [30]. A comparison between the three active modalities revealed that (a) CTPI induced the greatest improvement in SLR, followed by IF and, finally, TENS; and (b) as compared with the Sham stimulation, both CTPI and IF stimulation significantly improved the SLR scores, while the TENS only induced a borderline significant difference. Thus, our findings suggest that, among the three active modalities tested in the current study, CTPI may be the most suitable for potentially relieving LDH-induced radicular pain, while the effects of TENS are more equivocal. Notably, similar results were previously reported in the context of fibromyalgia [8], which is the main context in which CTPI has been examined to date.

To the best of our knowledge, this study is the first to systematically examine the change in SLR scores in response to specific electrotherapeutic modalities. Thus, the degree of improvement in the SLR scores (namely, 8.3 ${}^{\circ}$ for TENS, 11.9 ${}^{\circ}$ for IF stimulation, and 19.1 ${}^{\circ}$ for CTPI, with a maximum improvement of 32 ${}^{\circ}$ in one participant) cannot be directly compared with the results of previous studies. However, the improvement in SLR scores following CTPI application is comparable to or better than the improvement reported following other treatments, including some invasive procedures. For example, Medrik-Goldberg, Lifschitz [40] reported a 7 ${}^{\circ}$ improvement following a lidocaine injection; Kim, Hong [41] reported a 34 ${}^{\circ}$ improvement following a radiofrequency focal ablation (an invasive procedure); Meszaros, Olson [39] reported a 12.4 ${}^{\circ}$ improvement following a lumbar traction treatment of 60% of the body weight; Tambekar, Sabnis [42] reported a 15.3 ${}^{\circ}$ improvement following a manual treatment (Mulligan’s); and Demirel, Yorubulut [13] reported a 20.5 ${}^{\circ}$ improvement following 15 sessions of combined treatment that comprised hot-packs, deep-tissue massages, TENS, ultrasound, exercises, and lumbar traction.

Although deciphering the physiological mechanisms underlying the therapeutic effects of surface-induced electrical currents is beyond the scope of this study, several speculations can be raised. First, LDH is very often accompanied by local inflammation and by inflammation-associated physiological changes (edema, impaired microcirculation, etc. [43]), which induce the radicular pain [44]. Thus, although the effects of electrotherapy on such peripheral physiological processes are controversial [45, 46, 47], it is possible that the stimulation reduced the severity of local inflammation around the herniated disc [45, 48, 49], which decreased the radicular pain. In the case of CTPI, the ultrasound itself may have further reduced inflammation and swelling [7, 47]. Second, various pharmacological and physiological evidence supports a central activation theory for the reduction of pain by electrotherapeutic currents [50, 51, 52, 53], and various types of spinal and/or supra-spinal receptors are known to be involved in electrotherapy-induced antihyperalgesia, including opioid [51, 52], serotoninergic [54], and cholinergic [55] receptors. Notably, the relative degree to which each of the three stimulation modalities improved the SLR scores is concomitant with the degree to which each of these modalities was shown to effectively penetrate biological tissues (namely, the penetration efficiency of CTPI is the highest of the three, while that of TENS is the lowest [25]). As the inflammation in LDH is relatively deep within the tissue, it is plausible that, as compared with more superficial currents, currents that penetrated deeper into the tissue (a) better reduced the LDH-induced inflammation, e.g., by stimulating the paravertebral muscles and reducing edema [56]; and (b) recruited more deep-tissue afferents to further reduce pain [57]. However, more direct mechanistic studies of these and other peripheral and central mechanisms are required to determine whether these speculations are valid.

The unique design of our study, in which all participants received all the types of treatment in a single, randomized 2 h session, increased the participation rate and enabled us to minimize inter- and intra-individual variability. However, while this design enabled us to directly compare between the different modalities, it also necessitated some methodological compromises, which should be considered when interpreting our findings and designing future studies. First, since all treatments were conducted during the same session, we only studied short-term post-stimulation effects; similar long-term effects are also possible and could be mediated, e.g., through a gradual but consistent reduction of inflammation, especially if the treatments were repeated periodically (e.g., 2–3 times a week) as part of a long-term treatment program. These speculations must be tested empirically, and an optimal protocol should be developed. Second, restricting the session to 2 h limited both the number of modalities that could be examined and the stimulation and washout durations. Thus, while we chose to test only three electrotherapeutic modalities and a sham control, future studies should also test other modalities (and, possibly, other types of sham controls; see below) and, especially, the combination of TENS with ultrasound stimulation. In addition, prolonging the stimulation and washout durations would have been methodologically preferable, although it would also increase the session duration and the inter- and intra-subject variability, and lying supine for longer durations during the washout phase might be especially uncomfortable, and even painful, for patients with NRI. Third, due to the need to randomize the treatment modalities, some participants received the sham stimulation after they had already experienced an active stimulation modality. As the physical sensation of active stimulation is quite different from that of a sham stimulation, these patients were probably aware of the fact that they were given a sham treatment, thus compromising our ‘control’ condition. Indeed, while previous studies reported a ‘placebo effect’ when comparing the efficacy of electrotherapy in ‘real’ versus ‘control’ groups, in which case the participants cannot differentiate between the active and sham stimulation [58], such an effect was not observed in our study. Fourth, while the observer in our study was blind to the treatment condition, the experimenter who performed the SLR test was not – which could potentially bias the results. Finally, while we adhered to the sample size indicated by a preliminary power analysis, the sample size is still relatively small and should be increased in future studies.

5. Conclusions

We tested the short-term efficacy of three widely used electrotherapeutic stimulation modalities (TENS, IF stimulation, and CTPI) in improving SLR scores in patients with LDH-induced radicular pain. We found that a single 10 min stimulation session improved the SLR scores in all three modalities, and that CTPI induced the greatest improvement, followed by IF stimulation and, finally, TENS. Further studies are required to elucidate the mechanisms underlying the improvement in SLR and to examine the ability of other stimulation modalities, treatment protocols, and treatment programs to improve the SLR scores.

Footnotes

Acknowledgments

This work was conducted as part of a PhD thesis by EA, submitted to Tel Aviv University. The authors thank Dr. Ram Gal for his helpful comments on the manuscript.

Conflict of interest

The authors report no conflicts of interest.

Funding

There are no funders to report for this study.

References

Kreiner

Hwang

Easa

Resnick

Baisden

Bess

, et al. An evidence-based clinical guideline for the diagnosis and treatment of lumbar disc herniation with radiculopathy. Spine J. 2014; 14(1): 180-91.

Hoy

March

Brooks

Blyth

Woolf

Bain

, et al. The global burden of low back pain: estimates from the Global Burden of Disease 2010 study. Ann Rheum Dis. 2014; 73(6): 968-74.

Frymoyer

. Back pain and sciatica. N Engl J Med. 1988; 318(5): 291-300.

Wartenberg

. The signs of Brudzinski and of Kernig. J Pediatr. 1950; 37(4): 679-84.

Bogduk

. On the definitions and physiology of back pain, referred pain, and radicular pain. Pain. 2009; 147(1-3): 17-9.

Arts

Kursumovic

Miller

Wolfs

JFC

Perrin

Van de Kelft

, et al. Comparison of treatments for lumbar disc herniation: Systematic review with network meta-analysis. Medicine (Baltimore). 2019; 98(7): e14410.

Bellew

Michlovitz

Nolan

. Jr. Michlovitz’s Modalities for Therapeutic Intervention: FA Davis; 2016.

Almeida

Roizenblatt

Benedito-Silva

Tufik

. The effect of combined therapy (ultrasound and interferential current) on pain and sleep in fibromyalgia. Pain. 2003; 104(3): 665-72.

Auchstaetter

Luc

Lukye

Lynd

Schemenauer

Whittaker

, et al. Physical Therapists’ Use of Functional Electrical Stimulation for Clients With Stroke: Frequency, Barriers, and Facilitators. Physical Therapy. 2016; 96(7): 995.

10.

Machado

Santana

Tacani

Liebano

. The effects of transcutaneous electrical nerve stimulation on tissue repair: A literature review. Can J Plast Surg. 2012; 20(4): 237-40.

11.

Rushton

. Electrical stimulation in the treatment of pain. Disability and Rsehabilitation. 2002; 24(8): 407-15.

12.

Fuentes

Armijo Olivo

Magee

Gross

. Effectiveness of interferential current therapy in the management of musculoskeletal pain: a systematic review and meta-analysis. Phys Ther. 2010; 90(9): 1219-38.

13.

Demirel

Yorubulut

Ergun

. Regression of lumbar disc herniation by physiotherapy. Does non-surgical spinal decompression therapy make a difference? Double-blind randomized controlled trial. J Back Musculoskelet Rehabil. 2017; 30(5): 1015-22.

14.

Moustafa

Diab

. Extension traction treatment for patients with discogenic lumbosacral radiculopathy: a randomized controlled trial. Clin Rehabil. 2013; 27(1): 51-62.

15.

Ratajczak

Hawrylak

Demidas

Kuciel-Lewandowska

Boerner

. Effectiveness of diadynamic currents and transcutaneous electrical nerve stimulation in disc disease lumbar part of spine. J Back Musculoskelet Rehabil. 2011; 24(3): 155-9.

16.

Pop

Austrup

Preuss

Niedzialek

Zaniewska

Sobolewski

, et al. Effect of TENS on pain relief in patients with degenerative disc disease in lumbosacral spine. Ortop Traumatol Rehabil. 2010; 12(4): 289-300.

17.

Franca

FJR

Callegari

Ramos

LAV

Burke

Magalhaes

Comachio

, et al. Motor Control Training Compared With Transcutaneous Electrical Nerve Stimulation in Patients With Disc Herniation With Associated Radiculopathy: A Randomized Controlled Trial. Am J Phys Med Rehabil. 2019; 98(3): 207-14.

18.

Ghoname

White

Ahmed

Hamza

Craig

Noe

. Percutaneous electrical nerve stimulation: an alternative to TENS in the management of sciatica. Pain. 1999; 83(2): 193-9.

19.

Ramos

LAV

Callegari

França

FJR

Magalhães

Burke

Carvalho

APdMC,

et al. Comparison between transcutaneous electrical nerve stimulation and stabilization exercises in fatigue and transversus abdominis activation in patients with lumbar disk herniation: A randomized study. Journal of Manipulative and Physiological Therapeutics. 2018; 41(4): 323-31.

20.

Werners

Pynsent

Bulstrode

. Randomized trial comparing interferential therapy with motorized lumbar traction and massage in the management of low back pain in a primary care setting. Spine (Phila Pa 1976). 1999; 24(15): 1579-84.

21.

Bombardier

. Physical therapy management of low back pain: an exploratory survey of therapist approaches. Phys Ther. 2001; 81(4): 1018-28.

22.

Çıtak-Karakaya

Akbayrak

Demirtürk

Ekici

Bakar

. Short and long-term results of connective tissue manipulation and combined ultrasound therapy in patients with fibromyalgia. Journal of Manipulative and Physiological Therapeutics. 2006; 29(7): 524-8.

23.

Moretti

Marcondes

Provenza

Fukuda

Vasconcelos

Roizenblatt

. Combined therapy (ultrasound and interferential current) in patients with fibromyalgia: once or twice in a week? Physiotherapy Research International. 2012; 17(3): 142-9.

24.

Waschl

Morrissey

Rugelj

. The Efficacy of Ultrasound-facilitated Electrical Stimulation as an Adjunct to Exercise in Treating Chronic Neck and Shoulder Pain. Journal of Musculoskeletal Pain. 2014; 22(1): 78-88.

25.

Ariel

Ratmansky

Levkovitz

Goor-Aryeh

. Efficiency of Tissue Penetration by Currents Induced by Three Electrotherapeutic Techniques: A Comparative Study Using a Novel Deep-Tissue Measuring Technique. Phys Ther. 2019; 99(5): 540-8.

26.

Satoskar

Goel

Mehta

Goel

. Quantitative morphometric analysis of the lumbar vertebral facets and evaluation of feasibility of lumbar spinal nerve root and spinal canal decompression using the Goel intraarticular facetal spacer distraction technique: A lumbar/cervical facet comparison. J Craniovertebr Junction Spine. 2014; 5(4): 157-62.

27.

Dixon

Keating

. Variability in straight leg raise measurements. Physiotherapy. 2000; 86(7): 361-70.

28.

Koury

Scarpelli

. A manual therapy approach to evaluation and treatment of a patient with a chronic lumbar nerve root irritation. Phys Ther. 1994; 74(6): 548-60.

29.

Chow

Adams

Herbert

. Straight leg raise test high reliability is not a motor memory artefact. Aust J Physiother. 1994; 40(2): 107-11.

30.

Camino Willhuber

Piuzzi

. Straight Leg Raise Test. StatPearls. Treasure Island (FL), 2019.

31.

Boyd

. Measurement properties of a hand-held inclinometer during straight leg raise neurodynamic testing. Physiotherapy. 2012; 98(2): 174-9.

32.

Boland

Adams

. Effects of ankle dorsiflexion on range and reliability of straight leg raising. Australian Journal of Physiotherapy. 2000; 46(3): 191-200.

33.

Thelander

Fagerlund

Friberg

Larsson

. Straight leg raising test versus radiologic size, shape, and position of lumbar disc hernias. Spine (Phila Pa 1976). 1992; 17(4): 395-9.

34.

Ekedahl

Jönsson

Frobell

. Fingertip-to-Floor Test and Straight Leg Raising Test: Validity, Responsiveness, and Predictive Value in Patients With Acute/Subacute Low Back Pain. Archives of Physical Medicine and Rehabilitation. 2012; 93(12): 2210-5.

35.

Supik

Broom

. Sciatic tension signs and lumbar disc herniation. Spine (Phila Pa 1976). 1994; 19(9): 1066-9.

36.

Xin

Zhang

Fan

. Significance of the straight-leg-raising test in the diagnosis and clinical evaluation of lower lumbar intervertebral-disc protrusion. J Bone Joint Surg Am. 1987; 69(4): 517-22.

37.

Troup

. Biomechanics of the lumbar spinal canal. Clin Biomech (Bristol, Avon). 1986; 1(1): 31-43.

38.

Defrin

Ariel

Peretz

. Segmental noxious versus innocuous electrical stimulation for chronic pain relief and the effect of fading sensation during treatment. Pain. 2005; 115(1): 152-60.

39.

Meszaros

Olson

Kulig

Creighton

Czarnecki

. Effect of 10%, 30%, and 60% body weight traction on the straight leg raise test of symptomatic patients with low back pain. J Orthop Sports Phys Ther. 2000; 30(10): 595-601.

40.

Medrik-Goldberg

Lifschitz

Pud

Adler

Eisenberg

. Intravenous lidocaine, amantadine, and placebo in the treatment of sciatica: a double-blind, randomized, controlled study. Reg Anesth Pain Med. 1999; 24(6): 534-40.

41.

Kim

Hong

Lee

. Two-year clinical outcomes of radiofrequency focal ablation using a navigable plasma disc decompression device in patients with lumbar disc herniation: efficacy and complications. J Pain Res. 2018; 11: 2229-37.

42.

Tambekar

Sabnis

Phadke

Bedekar

. Effect of Butler’s neural tissue mobilization and Mulligan’s bent leg raise on pain and straight leg raise in patients of low back ache. J Bodyw Mov Ther. 2016; 20(2): 280-5.

43.

Govind

. Lumbar radicular pain. Aust Fam Physician. 2004; 33(6): 409-12.

44.

Goupille

Jayson

Valat

Freemont

. The role of inflammation in disk herniation-associated radiculopathy. Semin Arthritis Rheum. 1998; 28(1): 60-71.

45.

Kim

Lee

Kim

Baik

. Anti-Inflammatory Effects of Step Electrical Stimulation on Complete Freund’s Adjuvant (CFA) Induced Rheumatoid Arthritis Rats. J Nanosci Nanotechnol. 2019; 19(10): 6546-53.

46.

Burgess

Immins

Swain

Wainwright

. Effectiveness of neuromuscular electrical stimulation for reducing oedema: A systematic review. J Rehabil Med. 2019; 51(4): 237-43.

47.

Baumert

, Jr. Acute inflammation after injury. Quick control speeds rehabilitation. Postgrad Med. 1995; 97(2): 35-6, 9, 42 passim.

48.

do Carmo Almeida

Dos Santos Figueiredo

Barbosa Filho

de Abreu

Fonseca

FLA

Adami

. Effects of Transcutaneous Electrical Nerve Stimulation on Proinflammatory Cytokines: Systematic Review and Meta-Analysis. Mediators Inflamm. 2018; 2018: 1094352.

49.

Fang

Liang

Fang

. Transcutaneous electrical nerve stimulation attenuates CFA-induced hyperalgesia and inhibits spinal ERK1/2-COX-2 pathway activation in rats. BMC Complement Altern Med. 2013; 13: 134.

50.

Melzack

Wall

. Pain mechanisms: a new theory. Science. 1965; 150(3699): 971-9.

51.

Kalra

Urban

Sluka

. Blockade of opioid receptors in rostral ventral medulla prevents antihyperalgesia produced by transcutaneous electrical nerve stimulation (TENS). J Pharmacol Exp Ther. 2001; 298(1): 257-63.

52.

Sluka

Deacon

Stibal

Strissel

Terpstra

. Spinal blockade of opioid receptors prevents the analgesia produced by TENS in arthritic rats. J Pharmacol Exp Ther. 1999; 289(2): 840-6.

53.

Sluka

Walsh

. Transcutaneous electrical nerve stimulation: basic science mechanisms and clinical effectiveness. J Pain. 2003; 4(3): 109-21.

54.

Radhakrishnan

King

Dickman

Herold

Johnston

Spurgin

, et al. Spinal 5-HT(2) and 5-HT(3) receptors mediate low, but not high, frequency TENS-induced antihyperalgesia in rats. Pain. 2003; 105(1-2): 205-13.

55.

Radhakrishnan

Sluka

. Spinal muscarinic receptors are activated during low or high frequency TENS-induced antihyperalgesia in rats. Neuropharmacology. 2003; 45(8): 1111-9.

56.

Vena

Rubianto

Popovic

Fernie

Yadollahi

. The Effect of Electrical Stimulation of the Calf Muscle on Leg Fluid Accumulation over a Long Period of Sitting. Sci Rep. 2017; 7(1): 6055.

57.

Radhakrishnan

Sluka

. Deep tissue afferents, but not cutaneous afferents, mediate transcutaneous electrical nerve Stimulation – Induced antihyperalgesia. The Journal of Pain. 2005; 6(10): 673-80.

58.

Khadilkar

Odebiyi

Brosseau

Wells

. Transcutaneous electrical nerve stimulation (TENS) versus placebo for chronic low-back pain. Cochrane Database Syst Rev. 2008; (4): CD003008.

The effects of TENS,interferential stimulation,and combined interferential stimulation and pulsed ultrasound on patients with disc herniation-induced radicular pain

Abstract

BACKGROUND:

OBJECTIVE:

METHODS:

RESULTS:

CONCLUSIONS:

Keywords

1. Background

2. Methods

2.1 Participants

Table 1 Selected demographic data, stimulation intensities (Stim; in mA) at each active stimulation condition, and the SLR scores (in degrees) before (pre) and after (post) applying each stimulation modality

2.5 Statistical analyses

3. Results

5. Conclusions

Footnotes

Acknowledgments

Conflict of interest

Funding

References

Table 1
Selected demographic data, stimulation intensities (Stim; in mA) at each active stimulation condition, and the SLR scores (in degrees) before (pre) and after (post) applying each stimulation modality