Interferential Current in Lower Back
Condition: Lower Back
Study type: Interventional

Summary: 
      In our daily clinical practice, one of the most frequent reasons for consultation
      physiotherapists is low back pain. Regardless of the origin of the problem, the approach from
      physiotherapy contemplates the reduction of pain through different procedures, among which
      all those included in electrotherapy stand out, as commented by McKenzie et al. The use of
      electric currents for therapeutic purposes is widespread and studied in the field of
      physiotherapy. However, the use of medium frequency currents, and more specifically
      interferential currents, provides participants with a series of important advantages, both
      for the patient and for the therapist.The study of low back pain in relation to treatment
      with interferential currents has a series of obstacles, among which the quantification of
      such pain and the establishment of the different parameters of the therapeutic procedure
      stand out. The first problem the investigators face are to objectify something that, in
      itself, is completely subjective: pain. In addition, pain measurement is our only guide to
      follow the evolution of the patient who suffers it. Another important problem, as discussed
      by Ward and Lucas-Toumbourou, has to do with the controversy between the different studies
      related to the treatment of low back pain with interferential currents.

      For all the above, the approach to low back pain is complex and affects the social, labor and
      economic scale of the individual and society. Low back pain is the main cause of public
      spending for welfare and work concepts. It suffers at some point in life up to 80% of the
      general population and each year generates a cost equivalent to approximately between 1.7 and
      2.1% of its gross domestic product in a European countries.

      There is a lack of valid scientific studies on some aspects of the clinical management of low
      back pain and the usual clinical practice does not seem to be based strictly on the results
      of the researches carried out. The available data suggest that there are abuses of procedures
      whose benefits and risks are uncertain, while others that have proven to be more effective,
      safe, effective and / or efficient are underutilized. For this reason, clinical practice
      guidelines for non-specific low back pain have been developed in several countries in recent
      years. Since the first clinical practice guidelines developed in America and the United
      Kingdom (Quebec Task Force in 1987. In 1994, more than 30 guides who claim to be based on
      scientific evidence have been developed.

      Electroanalgesia is a set of procedures consisting of the application of an electric current
      through electrodes placed on the skin of the patient in order to stimulate myelinated nerve
      fibers, fast driving. This activation triggers, at the central level, the implementation of
      descending analgesic systems of an inhibitory nature on nociceptive transmission, transported
      by small-caliber unmyelinated fibers. In this way, a reduction in pain is obtained. In other
      words, it is a question of carrying out a "differential" sensory stimulation,
      transcutaneously, of the tactile proprioceptive fibers, with a high speed of conduction, with
      the minimum response of the nociceptive fibers, of slow conduction, and of the efferent motor
      fibers.

      The application of medium frequency interferential currents (4,000 Hz), in addition to
      reducing the pain caused by the stimulation of thick nerve fibers, produces the normalization
      of the neurovegetative balance. According to De Domenico, this means a cushioning of the
      orthosympathetic system, which is reflected in muscle relaxation and improved circulation,
      which also helps to reduce pain.

      But the clinical impact of interferential currents on non-specific chronic low back pain
      remains poorly studied. Thus, clinical trials show some controversy and support its efficacy
      in combination with other treatments. A systematic review found that the interferential
      current demonstrates advantages over placebo and without treatment when associated with
      exercises and massages. In contrast, the European clinical practice guideline for the
      treatment of chronic low back pain concluded that there was no evidence of its effectiveness
      compared to sham intervention or placebo. However, recent studies of a randomized clinical
      trial with interferential currents on patients with nonspecific chronic low back pain report
      very favorable results in terms of the reduction of perceived pain and functional disability.
    


Intervention name(s): Interferential current
Intervention type(s): Other
Intervention description(s): interferential currents of 4,000 Hz carrier frequency, 100 Hz of AMF, for 20 minutes and with an amplitude up to the motor threshold
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment