Effects of Dry Needling When Applied to the Infraspinatus Muscle in People With Chronic Shoulder Pain
Condition: Trigger Point Pain, Myofascial; Chronic Shoulder Pain
MeSH terms: Shoulder Pain; Myofascial Pain Syndromes
Study type: Interventional

Summary: 
      Up to 77% of patients with chronic shoulder pain have a trigger point (TrP) in the
      infraspinatus muscle. These TrPs can lead to pain, limitation of activities and reduced
      quality of life. Dry needling (DN) is gaining popularity as a treatment for TrPs in
      physiotherapy. However, its clinical effects remain poorly understood mechanistically and its
      neurophysiological effects little studied.

      The primary objective of this study is to determine the feasibility of a larger scale study.

      The secondary objective of this study is to to explore the immediate neurophysiological,
      biomechanical and clinical effects of DN and sham needling when applied to TrP of the
      infraspinatus muscle in people with chronic non-traumatic shoulder pain.
    

Detailed description: 
      Methodology

      In this randomized, double-blind, parallel-group trial, twenty adults with chronic
      non-traumatic shoulder pain and with a infraspinatus TrP will be recruited according to
      established criteria. Participants will be randomized into two groups: one group (n = 10)
      receiving a DN in the infraspinatus TrP and another group (n = 10) receiving a sham needling.

      Recruitment strategies

      Recruitment will be done through posters that will be posted on bulletin boards of the
      Faculty of Medicine and Health Sciences of the University of Sherbrooke and in physiotherapy
      clinics in the region. The persons interested will be invited to contact the research
      assistant in charge of the study to verify their eligibility to participate.

      Data collection procedure

      The experimental procedure will take place in a laboratory located at the Research Center on
      Aging in Sherbrooke, Quebec, Canada. Upon arrival, individuals will be greeted by a research
      assistant. Verification of the presence of TrP in the infraspinatus to confirm eligibility to
      participate will be carried out by a physiotherapist with more than 20 years of experience in
      the identification of TrPs and with the application of DN, according to the following
      procedure: Participants will be asked to lie in a decubitus lateral position on a treatment
      table and on the asymptomatic side. The upper arm will be supported on a box placed in front
      of them, so that the muscles can be relaxed, but the arm will be positioned in a and have a
      slight horizontal adduction to slightly stretch the fibers of the infraspinatus muscle.
      Manual palpation with flat fingers and perpendicular to the fibers will be used to identify
      the tight muscle band. Once a tight muscle band has been identified, the physiotherapist will
      search within this band for a contraction node, namely the TrP. Once she had identified this
      TrP with a non-toxic black Sharpie pencil, she will validate with the patient that the
      compression of this TrP reproduces local or referred pain. This pain should correspond to the
      pain patterns known to the infraspinatus according to Simons and Travell, 1999 and reproduce
      the pain known by the patient. This pain should be at least a 1/10 intensity on the visual
      analog scale (VAS). Ineligible participants will receive advices from the physiotherapist as
      well as a prescription for exercises related to their condition and a list of
      physiotherapists they can consult.

      The research assistant will explain the nature of the project to the selected participants,
      he will make sure that the participants have no contraindications to receive DN and/or for
      transcranial magnetic stimulation (TMS) examination, and he will obtain written informed
      consent. Participants will then complete a questionnaire used to collect baseline medical
      information.

      Intervention (DN and Sham)

      DN will be performed by a certified clinician, experienced with the technique. She will
      explain the purpose of the intervention and she will review the contraindications and
      precautions for DN to ensure that the procedure is safe. The technique used is recommended by
      l'Ordre professionnel de la physiothérapie du Québec (OPPQ). The clinician will insert a
      sterile disposable acupuncture needle, OPTIMED (non-silicone), 40 mm x 0.30 caliber. The
      direction of the needle will be slightly oblique, directly in the TrP and in the direction of
      the muscle fibers. The production of a twitch is expected, gliding and rotation of the needle
      may be performed to produce this effect, if necessary. The needle will be removed after the
      twitch. The same procedure will be used for the sham group, except that the needle will be
      inserted at the subcutaneous level, at the depth of the superficial adipous tissues
    

Intervention name(s): Dry needling; Sham needling (SN)
Intervention type(s): Other; Other
Intervention description(s): Intramuscular insertion of an OPTIMED 40mm x 0.3mm acupuncture needle in a trigger point of the infraspinatus muscle; Intradermal insertion of an OPTIMED 40mm x 0.3mm acupuncture needle over the infraspinatus region
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Dry needling; Infraspinatus; Neurophysiological effects