Invasive Techniques in Trigger Points (ITTP)

Myofascial pain syndrome (MPS) is present in up to 87% of the patients that present pain. MPS usually presents painful myofascial trigger points (MTrPs). One methodology used to quantify the pain in MPS is the algometry, which measures the pressure pain threshold (PPT). Invasive techniques in physiotherapy have become popular in the last years due to their clinical efficacy and evidence. Percutaneous Microelectrolysis (MEP®) and dry needling are techniques that are already in use for this syndrome. MEP® is a technique that employs a galvanic current up to 990 microAmperes, which is applied percutaneously with an acupuncture needle connected to the cathode. It is also known as low intensity percutaneous electrolysis. The aim of this study is to compare the effects in pain and muscle tone (measured with algometry and surface electromyography) of invasive techniques. Healthy subjects between 18 to 48 years old, both sex, presenting MTrPs in upper trapezius will be recruited. The secondary objectives are to determine the discomfort degree of each technique and if it is better to use MEP® with a fixed dose or with an algorithm in which the dose varies. The hypothesis, according to our previous studies, is that MEP® generates higher changes in PPT.

Dynamic low intensity percutaneous electrolysis will be applied in the upper trapezius trigger point with a fixed dose.

Static low intensity percutaneous electrolysis will be applied in the upper trapezius trigger point with a fixed dose.

Low intensity percutaneous electrolysis will be applied in the upper trapezius trigger point with an algorithm-based dose.

An acupuncture needle of 0.3 x 25 mm will be introduced perpendicularly into the upper trapezius trigger point. A movement with the needle will be done at 1 Hz for 120 seconds.

Cathodic low intensity percutaneous electrolysis will be applied through an acupuncture needle of 0.3 x 25 mm in the upper trapezius trigger point. A movement with the needle will be done at 1 Hz with an intensity of 600 micro-Amperes. If the patient refers discomfort, the procedure will be stopped and resumed totalling 120 seconds (total dose of 72 mC).

An acupuncture needle of 0.3 x 25 mm will be introduced perpendicularly into the upper trapezius trigger point for 120 seconds.

Cathodic low intensity percutaneous electrolysis will be applied through an acupuncture needle of 0.3 x 25 mm in the upper trapezius trigger point. The therapy will be done statically with an intensity of 600 micro-Amperes. If the patient refers discomfort, the procedure will be stopped and resumed totalling 120 seconds (total dose of 72 mC).

Cathodic low intensity percutaneous electrolysis will be applied through an acupuncture needle of 0.3 x 25 mm in the upper trapezius trigger point. The therapy will be done statically, at 600 micro-Amperes. If the patient refers discomfort, the procedure will be stopped and resumed. Treatment will finish when the patient does not refer any discomfort for a period longer than 60 seconds. Total dose in mC will be registered.

An acupuncture needle of 0.3 x 25 mm will be introduced perpendicularly up to 3 mm deep into the upper trapezius trigger point for 120 seconds.

Algometry is used to measure the Pressure Pain Threshold (PPT). PPT is defined as the minimum force applied which induces pain. It will be applied in the Myofascial Trigger points.

Algometry is used to measure the Pressure Pain Threshold (PPT). PPT is defined as the minimum force applied which induces pain. It will be applied in the Myofascial Trigger points.

Algometry is used to measure the Pressure Pain Threshold (PPT). PPT is defined as the minimum force applied which induces pain. It will be applied in the Myofascial Trigger points.

Algometry is used to measure the Pressure Pain Threshold (PPT). PPT is defined as the minimum force applied which induces pain. It will be applied in the Myofascial Trigger points.

Algometry is used to measure the Pressure Pain Threshold (PPT). PPT is defined as the minimum force applied which induces pain. It will be applied in the Myofascial Trigger points.

Electromyography (EMG) is used to measure muscular electrical activity at rest to determine the basal tone. Peak voltage and root mean square (RMS) voltage will be informed.

Electromyography (EMG) is used to measure muscular electrical activity at rest to determine the basal tone. Peak voltage and root mean square (RMS) voltage will be informed.

Electromyography (EMG) is used to measure muscular electrical activity at rest to determine the basal tone. Peak voltage and root mean square (RMS) voltage will be informed.

Electromyography (EMG) is used to measure muscular electrical activity at rest to determine the basal tone. Peak voltage and root mean square (RMS) voltage will be informed.

Electromyography (EMG) is used to measure muscular electrical activity at rest to determine the basal tone. Peak voltage and root mean square (RMS) voltage will be informed.

Electromyography (EMG) is used to measure muscular electrical activity at maximum voluntary contraction to determine the recruitment. Peak voltage and RMS voltage will be informed.

Electromyography (EMG) is used to measure muscular electrical activity at maximum voluntary contraction to determine the recruitment. Peak voltage and RMS voltage will be informed.

Electromyography (EMG) is used to measure muscular electrical activity at maximum voluntary contraction to determine the recruitment. Peak voltage and RMS voltage will be informed.

Electromyography (EMG) is used to measure muscular electrical activity at maximum voluntary contraction to determine the recruitment. Peak voltage and RMS voltage will be informed.

Electromyography (EMG) is used to measure muscular electrical activity at maximum voluntary contraction to determine the recruitment. Peak voltage and RMS voltage will be informed.

To determine how unpleasant the procedure is, the visual analog scale (VAS) will be used. Expresed in centimeters. Minimum value: 0 Maximum value: 10 A higher score implicates a worse outcome.

To determine how unpleasant the post-needling soreness is, a pain diary with the visual analog scale (VAS) will be used. The patient will register the pain intensity in the needle area. Expresed in centimeters. Minimum value: 0 Maximum value: 10 A higher score implicates a worse outcome.

Four times per day (in the morning, before lunch, in the afternoon, and in the evening) during the seven days following intervention.

To determine the amount of electric charge applied, the millicoulombs (mC) informed in the MEP device will be recorded.

Inclusion Criteria: Neck pain during the last 6 months Presence of a palpable taut band in the upper trapezius Presence of a hypersensitive tender spot in the taut band, with local or referred pain elicitation in response to compression PPT less than 3 Kg/cm2 Exclusion Criteria: Previous cervical and/or shoulder surgical intervention. Phobia to needles. Temporomandibular disorders. Medicated with anticoagulants Still receiving a treatment for the myofascial trigger points (Physical therapy, NSAIDs, etc.) Diagnosis of fibromyalgia. Radiculopathies and/or radicular pain Whiplash related neck pain Migraines Dizziness Endocrinal diseases Being pregnant Cancer