Dry Needling on Myofascial Trigger Points in Older Adults With Nonspecific Shoulder Pain

Efficacy of Dry Needling on Myofascial Trigger Points in Adults Over 65 Years Old With Non-specific Shoulder Pain: Single Blind Randomized Controlled Clinical Trial

Background: Non-specific shoulder pain has a high prevalence in older adults and provokes functional alterations. Besides, there are difficulties for its clinical diagnosis, lack of effectiveness in the treatment and not much evidence is found regarding invasive physical therapy techniques in this population. Purpose: To determine the efficacy of a single physical therapy intervention with deep dry needling on latent and active myofascial trigger points in older adults with non-specific shoulder pain. Methods: Pilot Study, Single Blind Randomized Controlled Clinical Trial on 60 subjects aged 65 and over, will be diagnosed with nonspecific shoulder pain. The study will be approved by the Clinical Research Ethics Committee of the area. Sample will be recruited at their home and at a care center, and randomly will be distributed in Experimental Group (n=30), which will be received a session of Deep Dry Needling on an active and a latent Myofascial Trigger Points of the infraspinatus muscle; and Control Group (n=30), receiving a session of Deep Dry Needling only on an active Myofascial Trigger Point. A blind examiner will be evaluated Pain Intensity, Pain Pressure Threshold (anterior deltoid; extensor carpi radialis brevis) and Grip Strength, before, immediately after intervention and after a week of treatment.

a single session of physical therapy intervention which will be consisted on Deep Dry Needling of the active MTrP most hyperalgesic to palpation of the infraspinatus muscle homolateral to painful shoulder

The same treatment described above for the Control Group, combined with the Deep Dry Needling of the most hyperalgesic latent MTrP, both located in the infraspinatus muscle homolateral to the painful shoulder.

Pain Intensity was measured with the Numerical Rating Scale (NRS) of 11 points (interval of 0-10), where 0 corresponds to no pain and 10 corresponds to the worst pain imaginable. In order to show a parametric analysis of the obtained data, a graphical representation of 11 spaces describes levels for the discrimination of the patient. The subjects will be asked to determine the subjective pain intensity of the painful shoulder using a finger.

Pressure Pain Threshold (PPT) will be measured with a WAGNER FDK/FDN Series Force Dial Fisher type analogue algometer (Wagner Instruments, Greenwich, USA) which varies between 0-10 kg/cm2. After indicating the most hyperalgesic latent Myofascial Trigger Point (MTrP) of anterior deltoid muscle (located in referred pain area and with the same C5-6 segmentary innervation levels), examiner will determine PPT of such point.

Maximum grip strength, defined as the maximum isometric muscular force in kg used in the manual pressure of a hydraulic dynamometer, will be measured with a JAMAR type hydraulic manual analogical dynamometer with an interval of 0-90kg to objectify the weakness of latent Myofascial Trigger Points (MTrPs) of the forearm. According to the fatigability of older adults, a single measurement will be performed to measure the manual grip strength.

Pressure Pain Threshold (PPT) will be measured with a WAGNER FDK/FDN Series Force Dial Fisher type analogue algometer (Wagner Instruments, Greenwich, USA) which varies between 0-10 kg/cm2. After indicating the most hyperalgesic latent Myofascial Trigger Point (MTrP) of extensor carpi radialis brevis muscle (located in referred pain area and with the same C5-6 segmentary innervation levels), examiner will determine PPT of such point.

Pain Intensity was measured with the Numerical Rating Scale (NRS) of 11 points (interval of 0-10), where 0 corresponds to no pain and 10 corresponds to the worst pain imaginable. In order to show a parametric analysis of the obtained data, a graphical representation of 11 spaces describes levels for the discrimination of the patient. The subjects will be asked to determine the subjective pain intensity of the painful shoulder using a finger.

Pressure Pain Threshold (PPT) will be measured with a WAGNER FDK/FDN Series Force Dial Fisher type analogue algometer (Wagner Instruments, Greenwich, USA) which varies between 0-10 kg/cm2. After indicating the most hyperalgesic latent Myofascial Trigger Point (MTrP) of anterior deltoid muscle (located in referred pain area and with the same C5-6 segmentary innervation levels), examiner will determine PPT of such point.

Maximum grip strength, defined as the maximum isometric muscular force in kg used in the manual pressure of a hydraulic dynamometer, will be measured with a JAMAR type hydraulic manual analogical dynamometer with an interval of 0-90kg to objectify the weakness of latent Myofascial Trigger Points (MTrPs) of the forearm. According to the fatigability of older adults, a single measurement will be performed to measure the manual grip strength.

Pressure Pain Threshold (PPT) will be measured with a WAGNER FDK/FDN Series Force Dial Fisher type analogue algometer (Wagner Instruments, Greenwich, USA) which varies between 0-10 kg/cm2. After indicating the most hyperalgesic latent Myofascial Trigger Point (MTrP) of extensor carpi radialis brevis muscle (located in referred pain area and with the same C5-6 segmentary innervation levels), examiner will determine PPT of such point.

Inclusion Criteria: people aged 65 or over with uni or bilateral non-specific shoulder pain and with at least one active and one latent MTrP in the infraspinatus homolateral to the painful shoulder Exclusion Criteria: prior diagnosis of myopathy or neuropathy; cognitive deficit in the medical record; cervical spine, rotator cuff tendons or glenohumeral joint problems in the medical record; corticoid infiltration or local anaesthetic during the previous year or during follow-up; surgical procedure affecting the upper limb or preceding cervical; ingestion of antiaggregant, anti-coagulant, analgesic or anti-inflammatory medication or abusive substances in the week prior to treatment and during follow-up were excluded from the study