The Efficacy of Low-level Laser on Cervical Myofascial Pain Syndrome
Condition: Myofacial Pain Syndromes
MeSH terms: Myofascial Pain Syndromes; Fibromyalgia; Facial Neuralgia; Syndrome; Facial Pain; Somatoform Disorders
Study type: Interventional

Summary: 
      Objective: To compare the effectiveness of application of low-level laser therapy (LLLT) to
      trigger points and traditional acupoints for patients with cervical myofascial pain syndrome
      (MPS).

      Design: A single-blinded, randomized, placebo-controlled trial Setting: University
      rehabilitation hospital Participants: One hundred and twenty one patients with cervical MPS
      Intervention: The investigators performed this experiment using low level 810-nm gallium
      aluminum arsenide (Ga-Al-As) laser. One hundred participants were randomly assigned to four
      treatment groups, including (1) acupoint therapy (2) acupoint control (3) trigger point
      therapy and (4) trigger point control groups.

      Main Outcome measures: The investigators evaluated the patient's visual analogue scale (VAS)
      pain scores, pressure pain threshold and cervical range of motion (ROM) before and after the
      therapy.
    

Detailed description: 
      Low level laser therapy (LLLT) has been promoted since 1960s. It was clinically applied on
      neurological, musculoskeletal and soft tissue disorders, with the effects such as
      acceleration of wound healing, edema reduction in human flexor tendon injuries, improvement
      of morning stiffness, and pain relief in rheumatoid arthritis and lateral epicondylitis. As
      for relief of musculoskeletal pain, however, the effect of LLLT is controversial. Some
      studies reported that LLLT was a safe and effective treatment for relief of musculoskeletal
      pain, while others considered LLLT as ineffective in treating certain musculoskeletal
      diseases.

      LLLT has been used to stimulate traditional acupoints, which is denoted as laser acupuncture.
      In addition to pain relief, laser acupuncture has been reported to be effective in a variety
      of disorders such as intractable hiccups,enuresis, as well as weight reduction. Nevertheless,
      the underlying mechanisms and modes of application of laser acupuncture remain unclear.

      There has been evidence that needle acupuncture on traditional acupoints or trigger points
      may ease neck pain. However, needle acupuncture has some limitations because it is an
      invasive procedure with risk of infection or pneumothorax. Besides, some patients were not
      able to tolerate the discomfort from needle manipulation during acupuncture therapy.

      LLLT is a type of non-invasive painless therapy and hence a good alternative to needle
      acupuncture. LLLT has been used to treat neck pain since 1981 and demonstrated significant
      reduction of pain intensity and improvement of cervical range of motion (ROM) in patients
      with cervical myofascial pain syndrome (MPS). In most of the studies on LLLT and cervical
      MPS, trigger points were chosen as the application area domain for LLLT. However, there is no
      report yet to compare the effectiveness of LLLT on trigger points and traditional acupoints.

      In the present single-blinded, randomized, controlled study, the investigators aimed to
      investigate the effectiveness of application of LLLT to the trigger points and traditional
      acupoints in patients with cervical MPS. The outcome measurement was pain relief and the
      improvement of cervical ROM, on which the findings could provide in-depth understanding of
      the therapeutic mechanism of LLLT and further allow more flexible options of clinical
      application.
    

Intervention name(s): low-level laser therapy
Intervention type(s): Other
Intervention description(s): An infrared (the low-level laser, class IIIb) gallium aluminum arsenide (Ga-Al-As) diode laser device (MediUm-TECH Medizingeräte GmbH, Germany) with a wavelength of 810nm and a maximum power output of 150mW in the continuous wave mode
Other intervention name(s): low-power laser therapy
Allocation: Randomized
Intervention model: Factorial Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: laser therapy; myofascial pain syndrome; acupoint; trigger point; range of motion