Effectiveness of Transcutaneous Electrical Nerve Stimulation in Patients With Acute Low Back Pain

Study Overview
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Brief Summary
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Introduction: Low back pain is one of the most common complaints in doctors' offices, and acute low back pain is characterized by episodes of pain with less than three weeks duration. The transcutaneous electrical nerve stimulation (TENS), based on the gate control theory of pain proposed by Melzack and Wall in 1965, has been used as an adjunctive therapy in the control of back pain, being a non-invasive, low cost, safe and easy to apply. No studies were found regarding the effectiveness of TENS in acute low back pain. Objective: To evaluate the effectiveness of TENS in pain management of patients with acute low back pain. Material and Methods: A randomized clinical trial, double-blinded and placebo-controlled. Patients were selected in the clinics of Federal de University of Sao Paulo (UNIFESP) according to the following criteria: acute low back pain, both genders, aged between 18 and 65 years, pain between 4 and 8cm in pain numeric scale (PNS) and who agreed to participate in the study. After signing the informed consent patients were randomly allocated into one of the groups: TENS group (TG) or Placebo Group (PG). In TG was applied conventional TENS with frequency and intensity variation (FIV) effect, frequency of 100 hertz, a pulse width of 60μs and intensity adjusted according to the individual baseline for each patient without causing muscular contraction. The electrodes were arranged in a cross shape in the paravertebral region (levels T12-L1 and L5 - S1). In PG the same procedures were adopted, but did not occur electrical stimulus. Patients were informed that they could or could not feel electric shocks. Treatment consisted of 10 sessions (2x / week / 5 weeks), with each session lasting 30 '. Assessments were made at the following times: T0 (baseline), T1 to T10 (the beginning and end of each session), T11 (after the last session), T30 (30 days after the last session) and T60 (60 days after the last session). Assessment tools: PNS for pain, short-form 36 (SF-36), Roland-Morris, self-assessment of improvement (Likert scale) and drug consumption (daily).

Conditions
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Low Back Pain

Intervention / Treatment
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* Device: TENS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: acute low back pain both genders aged between 18 and 65 years pain between 4 and 8cm in PNS (pain numeric scale) who agreed to participate in the study. Exclusion Criteria: Patients with pain of inflammatory, neoplastic or infectious origin, with cardiac pacemaker, previous back surgery, signs of irritation of nerve roots, vertebral fracture, which changed the physical activity in the last three months, and pregnant women

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: TENS group<br>It was applied conventional TENS with FIV effect, frequency of 100 Hertz, a pulse width of 60μs and intensity adjusted according to the individual baseline for each patient without causing muscular contraction. The electrodes were arranged in a cross shape in the paravertebral region (levels T12-L1 and L5 - S1). Treatment consisted of 10 sessions (2x / week / 5 weeks), with each session lasting 30 '. | Device: TENS<br> <br> |
| Placebo Comparator: Placebo group<br>In Placebo group the same procedures of the TENS group were adopted, but did not occur electrical stimulus. | Device: TENS<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in pain assessed by visual analog scale |  | Baseline; 1,2,3,4,5,6,7,8,9,10; 30 and 60 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in functional capacity assessed by the Roland Morris questionnaire |  | Baseline; 10; 30 and 60 days | 
| Change in self-assessment of improvement assessed by a likert scale |  | Baseline; 10; 30 and 60 days | 
| Change in Quality of life assessed by the SF-36 questionnaire |  | Baseline; 10; 30 and 60 days | 
| Change in Drug consumption assessed by the number of NSAIDs consumed |  | Baseline; 10; 30 and 60 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Transcutaneous Electric Nerve Stimulation, Pain