Percutaneous Neuromuscular Electrical Stimulation in Patients With Chronic Low Back Pain

Chronic low back pain is a common musculoskeletal condition affects the general population. Low back pain constitutes a major burden to health care system and society. Several authors have found that the deep abdominal muscles and multifidus are affected in low back pain. Dry needling has shown improve the cross-sectional area of the multifidus. Percutaneous electrical nerve stimulation has shown reduce pain in several conditions. There are not studies that had investigated the impact of percutaneous neuromuscular electrical stimulation (PNMES) in the deep muscles in patients with chronic low back pain.

Hypothesis: PNMES in the multifidus muscle plus motor control exercise program in patients with chronic low back pain is better than sham PNMES plus exercise and transcutaneous electrical nerve stimulation (TENS) plus exercise

Randomized, double-blind, placebo controlled clinical trial, using percutaneous neuromuscular electrical stimulation (PNMES). PNMES is technique to provide a transcutaneous electrical nerve stimulation current throughout needling filaments place close to the nerve.

Study Aims:

Aim #1: The primary aim of the study is to compare the effect of the short, medium and long-term of PNMES on muscle activation (increased cross-sectional area in activation) and the function of multifidus and abdominal transverse muscle in patients with chronic low back pain with random assignment to four treatments: PENS plus motor control exercise program or Sham PNMES (introducing the needle) plus motor control exercise program or Transcutaneous Electrical Nerve Stimulation (TENS) plus motor control exercise program or Sham PNMES (without inserting the needle) plus motor control exercise program.

Aim #2: The secondary aim of the study is to compare the effect of the short, medium and long-term of PNMES on pain as measured by visual analogue scale (VAS), chronic Pain Grade Questionnaire, pressure pain threshold (PPT), area and distribution of pain, conditioned pain modulation and temporal summation in patients with chronic low back pain with random assignment to four treatments: PNMES plus motor control exercise program or Sham PNMES (introducing the needle) plus motor control exercise program or Transcutaneous Electrical Nerve Stimulation (TENS) plus motor control exercise program or Sham PNMES (without inserting the needle) plus motor control exercise program.

Aim #3: To compare the effect of the short, medium and long-term of PNMES on disability as measured by Oswestry Disability Index, strength and quality of life with random assignment to four treatments: PENS plus motor control exercise program or Sham PNMES (introducing the needle) plus motor control exercise program or Transcutaneous Electrical Nerve Stimulation (TENS) plus motor control exercise program or Sham PNMES (without inserting the needle) plus motor control exercise program.

Aim #4: To estimate the immediate effects of the PNMES technique after the first session.

Aim #5: To determine if psychological factors (anxiety, depression, kinesiophobia and catastrophism) change with any of the treatments and if is related with the primary and secondary outcomes.

Aim #6: To evaluate the change perceived by the patient measured with Global Rating of Change Scale (GROC).

Aim Aim #7: Validation of placebo groups by assessing patient blindness

Eligibility Criteria:
Inclusion Criteria:

- Low back pain more than 90 days of evolution

Exclusion Criteria:

* Spondylarthrosis
* History of fractures, luxations, surgery and/or musculoskeletal disorders in low back and lower limb.
* Leg pain or neuropathic pain (LANSS \<12).
* Neurological disorders, inflammatory and/or degenerative diseases.
* Having received as treatment techniques that involve needles on the previous 6 months to study enrollment or having received percutaneous electrical stimulation as a treatment before.
* Physiotherapy treatment in the last 4 weeks.
* Specific lumbar pathology, fibromyalgia, unstable cardiovascular diseases, pregnant women or under suspect of pregnancy.
* Contraindications of needle's insertions: anticoagulant therapy, needle phobia, diabetes, hypothyroidism, lymphoedema, muscular diseases).
* Contraindications of electrical current.
* Drugs: morphine or opioids drugs.
* Depression
* Judicial dispute