Shoulder Pain
Conditions
Keywords
Dry needling, Percutaneous electrolysis, Physiotherapy, Manual therapy, Exercise
Brief summary
Dry needling (DN) and percutaneous electrolysis (PE) are minimally invasive physiotherapy techniques commonly used for the management of myofascial trigger points. DN consists of inserting a fine filiform needle into a hyperirritable area within a taut band of skeletal muscle, with the aim of eliciting local twitch responses and reducing myofascial pain. PE follows a similar needle-based approach but combines the mechanical stimulus of the needle with the application of a galvanic electrical current, producing an electrochemical reaction in the targeted tissue. Both techniques have been increasingly used in clinical practice for musculoskeletal pain conditions, including shoulder pain, although the evidence comparing their relative effectiveness remains limited. Shoulder pain is one of the most prevalent musculoskeletal disorders and is frequently associated with the presence of active myofascial trigger points. Among the shoulder muscles, the infraspinatus has been identified as a clinically relevant structure because its trigger points may reproduce referred pain patterns commonly reported by patients with shoulder symptoms and may contribute to pain, reduced strength, altered mobility, and functional disability. Previous studies have suggested that invasive treatment of infraspinatus trigger points may produce short-term improvements in pain sensitivity and shoulder-related symptoms. However, most available research has examined dry needling or percutaneous electrolysis separately, and direct comparisons between both interventions in patients with shoulder pain remain scarce. The physiological mechanisms underlying these techniques are not yet fully understood. Dry needling is thought to act through mechanical and neurophysiological mechanisms, including disruption of dysfunctional motor endplates, reduction of local nociceptive input, elicitation of local twitch responses, and activation of segmental and descending inhibitory pathways. Percutaneous electrolysis may share some of these needling-related effects, while also adding a galvanic current that may induce local biochemical changes and promote tissue recovery processes. Nevertheless, it remains unclear whether the addition of electrical current provides superior clinical effects compared with dry needling alone. Since limited research has directly compared dry needling and percutaneous electrolysis applied to active myofascial trigger points of the infraspinatus in patients with shoulder pain, the present study aimed to compare the effectiveness of both techniques as complementary interventions to manual therapy and therapeutic exercise. Specifically, this study sought to determine whether percutaneous electrolysis or dry needling produced greater short-term improvements in pain intensity and shoulder-related disability.
Interventions
Dry needling will be performed on the most symptomatic active myofascial trigger point of the infraspinatus muscle. Participants will be placed in prone, and the skin will be disinfected with 2% chlorhexidine. A sterile solid filiform needle will be inserted into the trigger point using Hong's technique, consisting of repeated fast-in and fast-out needle movements for 30 seconds, with the aim of eliciting 3-5 local twitch responses. During the 30 seconds procedure, the needle will be connected to the percutaneous electrolysis device (without current) for blinding purposes.
Percutaneous electrolysis will be applied to the most symptomatic active myofascial trigger point of the infraspinatus muscle. Participants will be positioned in prone, and the skin will be cleaned with 2% chlorhexidine. A sterile solid filiform needle will be inserted into the trigger point using a fast-in and fast-out needling approach, with the aim of eliciting 3-5 local twitch responses. During the procedure, a galvanic current of 0.3 mA was applied for 30 seconds.
Manual therapy interventions consist of soft tissue techniques targeting the upper, middle, and lower trapezius, levator scapulae, rhomboids, teres minor, and infraspinatus muscles. The pressure will be adapted to each participant's tolerance and will not exceed moderate pain intensity. Scapular mobilization techniques will be also performed in side-lying, including elevation, depression, protraction, retraction, upward rotation, and downward rotation.
The programme include assisted mobility exercises for shoulder flexion, abduction, external rotation, and internal rotation, followed by strengthening exercises for flexion, extension, abduction, internal rotation, and external rotation. Anterior and posterior shoulder capsule stretching and unloaded Codman pendulum exercises will be also included. Participants will be instructed to perform the exercises once daily until the follow-up assessment, keeping pain below 3-4 points on the visual analogue scale.
Percutaneous electrolysis will be applied to the most symptomatic active myofascial trigger point of the infraspinatus muscle. Participants will be positioned in prone, and the skin will be cleaned with 2% chlorhexidine. A sterile solid filiform needle will be inserted into the trigger point using a fast-in and fast-out needling approach, with the aim of eliciting 3-5 local twitch responses. During the procedure, a galvanic current of 3 mA was applied for 3 seconds.
Sponsors
Study design
Intervention model description
Randomized, Double-Blinded Controlled Trial
Eligibility
Inclusion criteria
* Adults * Presence of shoulder pain for at least 3 months. * Shoulder pain intensity greater than 3 points on the visual analogue scale (VAS). * Shoulder-related disability greater than 20 points on the DASH questionnaire. * Presence of at least one active myofascial trigger point in the infraspinatus muscle. * Reproduction of the patient's familiar shoulder pain during palpation of the infraspinatus trigger point. * Ability to understand the study procedures and provide written informed consent.
Exclusion criteria
* Previous shoulder surgery or traumatic shoulder injury in the affected region. * Presence of severe structural or systemic pathology affecting the shoulder region, such as fracture, tumour, infection, inflammatory disease, or neurological disorder. * Clinical signs suggestive of cervical radiculopathy or other neurological conditions that could explain the shoulder symptoms. * Use of physiotherapy treatment, invasive therapy, or analgesic/anti-inflammatory medication during the week before participation. * Contraindications to dry needling or percutaneous electrolysis, including needle phobia, anticoagulant therapy, bleeding disorders, pregnancy, pacemaker or implanted electrical devices, local skin infection, or altered skin sensitivity in the treatment area.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Pain intensity | Baseline (before the intervention on Day 1) and 7 days after the intervention | Pain intensity will be assessed using a 10-point visual analogue scale (VAS), where 0 indicates no pain and 10 represents the worst imaginable pain. Participants will be asked to rate their perceived shoulder pain before the intervention and at the 7-day follow-up. Higher scores indicated greater pain intensity. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Shoulder disability | Baseline (before the intervention on Day 1) and 7 days after the intervention | Shoulder-related disability will be evaluated using the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH). This instrument assesses the patient's ability to perform daily activities involving the upper limb. Scores range from 0 to 100, with higher scores indicating greater disability. |
| Adverse effects | From completion of the intervention on Day 1 to 7 days after the intervention | Adverse effects will be recorded by asking participants to report any undesirable symptoms or sequelae occurring during or after the interventions. These include any short- or medium-term symptoms considered intolerable by the patient or requiring additional care. |
| Interventions tolerance | Immediately after completion of the intervention on Day 1 | How patients tolerate the invasive physiotherapy procedures will be assessed using a 10-point visual analogue scale (VAS), where 0 indicated no pain and 10 represented the worst imaginable pain. Participants will be asked to rate how painful they perceived the assigned intervention. Higher scores indicated greater pain intensity. |
Countries
Spain