EMG Activity Before, During and After Dry Needling
Condition: Neck Pain
MeSH terms: Neck Pain
Study type: Interventional

Summary: 
      An experimental study will be conducted to evaluate the effect of a single dry needling
      session on surface EMG activity (primary outcome measure), muscle tone, elasticity, stiffness
      and pain (secondary outcome measures) of the upper trapezius, in female office workers with
      trapezius myalgia.
    

Detailed description: 
      Neck-shoulder pain is a frequent problem in office workers . These complaints are often
      related to myofascial problems of neck and shoulder muscles in which the upper trapezius is
      frequently involved. Trapezius myalgia (TM) is characterized by pain, palpable stiffness and
      tenderness of the upper part of the trapezius muscle. Several studies show that myofascial
      trigger points (MTrP) have an important role in the development and maintenance of myofascial
      pain.

      Trigger points are defined as hyperirritable nodules in a contracture of skeletal muscle
      fibers.

      The pathophysiology of MTrPs is still unclear but several hypothesis exist. The most
      plausible explanation is that, due to sustained postures or repetitive low-level tasks, a
      sustained irritation of motor end plates with an excessive release of acetylcholine arises.
      This may lead to a persistent sarcomere contraction, leading to an impaired blood
      circulation, a reduced oxygenation and energy depletion, sensitizing nociceptors and causing
      pain.

      Dry needling (DN) is a myofascial treatment technique, in which a thin, solid filiform needle
      is inserted directly into the MTrP. During dry needling, local twitch responses (LTR) can be
      elicited. These are involuntary contractions of muscle fibers, leading to muscle relaxation,
      an increase in blood flow, recovery of the muscle metabolism and thus a reduction of pain and
      stiffness.

      In this experimental study, 25 female office workers with trapezius myalgia are recruited
      from several work places with predominantly computer based tasks. These subjects have to
      perform at least 20 hours a week of computer work and this since at least one year. Subjects
      are included based on online questionnaires, a clinical examination of neck an shoulder and
      the presence of MTRP 2 in the upper trapezius. All participants will receive information and
      have to sign an informed consent form.

      Participants will be subjected to baseline assessment which involves measuring resting
      surface EMG activity, muscle tone, stiffness, elasticity and pain. Then, subjects have to
      perform a computer task during 20 minutes while surface EMG activity will be measured every 5
      minutes. After this computer task, all measurements will be repeated. After a resting period
      of 10 minutes, baseline measurements are repeated, followed by a computer task of 20 minutes
      and repetition of the same assessment. After this computer task, a single dry needling
      session of MTrP 2 of the upper trapezius will be performed bilaterally. During this
      treatment, surface EMG activity will be measured to captivate the EMG activity during local
      twitch responses.

      This is followed by repeating the same measurements 1 and 10 minutes after dry needling.
    

Intervention name(s): Dry needling
Intervention type(s): Procedure
Intervention description(s): Dry needling (DN) is a myofascial treatment technique, in which a thin, solid filiform needle is inserted directly into the MTrP. During dry needling, local twitch responses (LTR) can be elicited. These are involuntary contractions of muscle fibers, leading to muscle relaxation, an increase in blood flow,recovery of the muscle metabolism and thus a reduction of pain and stiffness.
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Other
Keywords: Dry needling; office workers; myofascial pain; electromyography