Effects of Percutaneous Electrical Stimulation in Patients With Chronic Supraspinatus Tendinopathy

Effects of Percutaneous Electrical Stimulation Combined With a Therapeutic Exercise Program in Patients With Chronic Supraspinatus Tendinopathy

The aim of this clinical trial is to evaluate the effects of two percutaneous stimulation techniques-Percutaneous Electrical Stimulation (PENS) and Percutaneous Electrolysis (PE)-combined with a therapeutic exercise (TE) program for the shoulder joint complex, on pain and function in individuals with chronic supraspinatus tendinopathy.

The main question this study seeks to answer is: Would incorporating percutaneous electrical stimulation (PENS) of the axillary and suprascapular nerves and galvanic percutaneous stimulation (PE) of the supraspinatus tendon into a therapeutic exercise (TE) program for the shoulder joint complex improve therapeutic outcomes in terms of pain, function, and upper limb disability? Based on an exercise program in all groups, researchers will compare the efficacy of active PENS and PE, as well as placebo, in all their combinations.

Participants will undergo a 12-week exercise program, during which they will receive four sessions (one session per week) of active percutaneous electrical stimulation or a placebo during the first month.

Participants will:

• Visit the center on four separate occasions for results measurement.
• Keep a session log to verify adherence to the exercise program.

Study Overview

• Status: Not yet recruiting
• Conditions: Supraspinatus Tendinopathy
• Intervention / Treatment: Procedure: EP + PENS + ET; Procedure: EP + PENS placebo + ET; Procedure: EP placebo + PENS + ET; Procedure: EP placebo + PENS placebo + ET

Detailed Description

Four study groups will be established, constituting the arms of the clinical trial.

Intervention Group 1 (EP + PENS + TE)

This group will consist of individuals with chronic supraspinatus tendinopathy who will receive a treatment consisting of four sessions of percutaneous electrical stimulation (one session per week) using a dual approach: applied to the supraspinatus tendon (using the electrical EP modality-percutaneous electrolysis) and to the axillary and suprascapular nerves (using the electrical PENS modality), together with a therapeutic exercise (TE) program aimed at strengthening the shoulder joint complex.

For the localization of the target structures in the affected shoulder-the supraspinatus tendon and the axillary and suprascapular nerves-a Logiq E R8 ultrasound device (General Electric®) with an L4-12T-RS transducer will be used.

The electrical stimulation program (EP and PENS) will be applied once per week for four weeks. The exercise program will be carried out for 12 weeks at home, with a supervised process of instruction and guidance regarding both the exercises and the prescribed dosage. To ensure treatment safety, particularly in the case of percutaneous electrical stimulation, a protocol for reporting and monitoring adverse effects will be implemented and maintained until 30 days after the last intervention.

EP will be performed using the EPTE® Bipolar system under ultrasound guidance, with the probe positioned longitudinally over the supraspinatus tendon. A needle (negative electrode) from Agupunt® (Barcelona, Spain), measuring 0.30 × 40 mm, will be inserted percutaneously at an approximate angle of 45° relative to the patient's surface. A 5 × 5 cm adhesive electrode (positive electrode) will be placed along the tendon-muscle pathway to close the electrical circuit. A continuous current of 350 µA intensity will be applied for 80 s, with three electrical charge deposits in different trajectories within the structurally affected area of the supraspinatus tendon. This microcurrent-level intensity produces a minimal electrical sensation that is barely perceptible and not associated with pain.

The patient will be placed in the supine position, with the upper limb in internal rotation and the hand positioned between the ipsilateral gluteus and the treatment table. If the patient is unable to maintain this position due to the pathology itself, the upper limb will be placed in the most tolerable position of shoulder internal rotation.

PENS will be applied immediately afterwards using the EPTE® Bipolar system under ultrasound guidance. For identification of the axillary nerve, the ultrasound probe will be placed longitudinally along the humerus over the middle-posterior deltoid muscle. For identification of the suprascapular nerve, the probe will be placed longitudinally over the supraspinatus muscle in order to visualize, from superficial to deep, the trapezius muscle, the supraspinatus muscle, and the suprascapular nerve within the supraspinous fossa. The patient will be placed in the prone position with the shoulders at 90° of abduction and the elbows flexed.

In both cases, an Agupunt® needle (Barcelona, Spain) measuring 0.30 × 60 mm will be inserted percutaneously at an approximate angle of 45°-55° relative to the patient's surface and positioned as close as possible to the nerve. In this case, since a symmetrical biphasic current without polar charge is used, each electrode will be connected to a needle to close the circuit.

To confirm the correct placement of the needle, each nerve will be stimulated using a pointer with several electrical pulses at a frequency of 5 Hz. Needle placement will be considered adequate if electrical stimulation with the pointer produces a visible muscle contraction in the innervated muscles. Subsequently, the circuit will be connected and a symmetrical biphasic rectangular current will be applied at a frequency of 12 Hz for 16 minutes, with an intensity adjusted to produce the strongest possible muscle contraction without causing pain.

The 12-week home-based exercise program aims to restore pain-free mobility and improve shoulder stability through exercises designed to strengthen the rotator cuff and scapular muscles. It consists of three phases and a total of 16 exercises, which will be progressively combined to complete the training sequence. The exercises for each phase will be provided to participants in written and audiovisual formats. Patients will perform three sessions per week. Exercise adherence will be recorded using an exercise diary.

This program was designed following two systematic reviews of clinical trials conducted by our research group, with several objectives: to categorize the types of exercises used in therapeutic programs, with a particular focus on those performed with elastic bands; and to evaluate the effects of home-based exercise programs compared with supervised exercise in patients with chronic rotator cuff tendinopathy.

Several in-person instruction, learning, and supervision sessions will be conducted throughout the intervention period, coinciding with the electrical stimulation sessions. With the assistance of the physiotherapist and audiovisual materials, each patient will learn the exercises and the methodology, practice them, and resolve any questions that may arise.

To facilitate adherence and performance of the program at home, participants will receive a list of exercises with a QR code linking to a video demonstrating the exercises to be performed in each phase. In this way, the patient will only need to play the video and imitate the exercises according to the prescribed regimen. In addition, they will receive an information sheet describing the progression across phases and the technical details: (i) maximum pain level during exercise and during the following 24 hours ≤ 5/10; and (ii) perceived exertion level associated with exercise repetitions equal to 7/10 on a numerical scale.

According to this latter condition, a mixed repetition model will be used, in which participants will perform a single set of up to 15 repetitions, always maintaining a value of 7/10 according to the Rating of Perceived Effort (RPE) scale. These thresholds do not directly correspond to percentages of one-repetition maximum (1RM), but they have been considered valid for prescribing therapeutic exercise in patients with pain. Load will be adjusted according to the reference indicated by modifying the tension and resistance of the elastic band. In any case, if the patient reports a higher perceived exertion or pain level, the load will be adjusted to maintain the values within the indicated range.

Intervention Group 2 (EP + placebo PENS + TE)

Patients assigned to this group will receive four EP sessions under the same conditions described in the previous group, together with four placebo PENS sessions. Likewise, the electrical stimulation program (EP and placebo PENS) will be applied once per week. The exercise program will also be carried out for 12 weeks (three sessions per week) and will include the same guidance and learning process described in the previous group.

In the case of placebo PENS, the patient position and procedure will be identical to those described in Group 1, although without the application of electrical current. The needle will be connected to the stimulation device with the same treatment duration but without intensity adjustment, so that the device light and the acoustic signal at the end of treatment will occur in the same way. This placebo method has been used in other studies with simulated percutaneous stimulation.

Intervention Group 3 (placebo EP + PENS + TE)

Patients assigned to this group will receive four placebo EP sessions and four PENS sessions under the conditions described in the previous group. Similarly, the electrical stimulation program (placebo EP and PENS) will be applied once per week. The exercise program will also be performed for 12 weeks (three sessions per week) and will include the same guidance and learning process described in the previous group.

In the case of placebo EP, the patient position and procedure will be identical to those described in Group 1, although without the application of electrical current. The needle will be connected to the stimulation device with the same treatment duration but without intensity adjustment, so that the device light and the acoustic signal at the end of treatment will occur in the same way. This placebo method has been used in other studies with simulated percutaneous stimulation.

Control Group (placebo EP + placebo PENS + TE)

Patients assigned to this group will receive four placebo EP sessions and four placebo PENS sessions under the same conditions described in Experimental Group 1. Likewise, the placebo electrical stimulation program will be applied once per week. The exercise program will also be performed at home for 12 weeks (three sessions per week) and will include the same guidance and learning process described in the previous group.

In the case of placebo EP and placebo PENS, the patient position and procedure will also be identical, but without the application of electrical current. The needles will be connected to the stimulation device for the same treatment duration but without intensity adjustment, so that the device light and the acoustic signal at the end of treatment will occur in the same way.

• Study Type: Interventional
• Enrollment (Estimated): 64
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: José-Vicente Toledo-Marhuenda, Ph D; Phone Number: 9260 Ext. +0034 965919260; Email: josetoledo@umh.es

Study Locations

• Spain
  • Alicante
    • San Vicent del Raspeig, Alicante, Spain, 03690
      • Centro de Fisioterapia VToledo.
      • Contact: Antonio Riera-Lara, Physiotherapist; Phone Number: +0034 96567369 +0034 96567369; Email: informacion@fisioterapiavtoledo.com
      • Contact: Sergio-Iván Fernández-Lorente, Physiortherapist; Phone Number: +0034 96567369 +0034 96567369; Email: informacion@fisioterapiavtoledo.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Subjects attending the shoulder unit of the traumatology and orthopedic surgery service at Clínica HLA Vistahermosa (TraumaVist) who are clinically diagnosed with supraspinatus tendinopathy (M75.1 Rotator cuff tendinopathy - ICD-10), according to the following criteria (Desmeules et al., 2025).

  • Participants of both sexes, aged between 18 and 65 years, diagnosed with chronic supraspinatus tendinopathy, or any of the related terms, provided they also meet the conditions detailed below.
  • Painful symptoms associated with the insertion area of the supraspinatus tendon, present for at least 3 months, of non-traumatic origin, which increase with palpation (score equal to or greater than 3/10 on a numerical pain scale) and with resisted movements, and not associated with signs of nerve root irritation.
  • Structural changes in the supraspinatus tendon (tendinosis), observed via ultrasound or MRI, and confirmed by a specialist physician.
  • Positive results in at least 2 of the 5 assessment tests: Hawkins-Kennedy, Neer, Jobe, painful arc of motion, and resisted external rotation.
  • Attend the center, referred by a specialist in traumatology and orthopedics, with a prescription for physiotherapy treatment.

Exclusion Criteria:

• Individuals with any of the following circumstances will be excluded:

  • Intratendinous calcification in the supraspinatus muscle.
  • Partial or complete tear of any rotator cuff structure.
  • Serious illnesses, diabetes, or systemic inflammatory disease.
  • Pregnant women (at any stage of pregnancy).
  • Presence of concomitant pathology in the affected shoulder joint complex at the time of recruitment (previous trauma, capsulitis, fracture and dislocation, history of surgery, entrapment neuropathies, among others).
  • Regular analgesic or anti-inflammatory pharmacological treatment, including corticosteroid injections in the area, within the 6 months prior to recruitment.
  • Difficulty understanding and following the intervention program, in any of its modalities (percutaneous electrical stimulation and exercises). • Individuals with belonephobia (fear of needles), or a contraindication for the application of either percutaneous electrical stimulation technique (EP or PENS).
  • High scores on the Tampa - TSK-11 kinesiophobia scale (≥36 points).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention group 1 (EP + PENS + ET); Percutaneous Electrolysis (EP) + Percutaneous Electrical Nerve Stimulation (PENS) + Therapeutic Exercise (ET)	Procedure: EP + PENS + ET; Percutaneous Electrolysis (EP) + Percutaneous Electrical Nerve Stimulation (PENS) + Therapeutic Exercise (ET)
Active Comparator: Intervention group 2 (EP + PENS placebo + ET); Percutaneous Electrolysis (PE) + Percutaneous Electrical Nerve Stimulation (PENS - placebo) + Therapeutic Exercise (ET)	Procedure: EP + PENS placebo + ET; Percutaneous Electrolysis (PE) + Percutaneous Electrical Nerve Stimulation (PENS - placebo) + Therapeutic Exercise (ET)
Active Comparator: Intervention group 3 (EP placebo + PENS + ET); Percutaneous Electrolysis (EP - placebo) + Percutaneous Electrical Nerve Stimulation (PENS) + Therapeutic Exercise (ET)	Procedure: EP placebo + PENS + ET; Percutaneous Electrolysis (EP - placebo) + Percutaneous Electrical Nerve Stimulation (PENS) + Therapeutic Exercise (ET)
Active Comparator: Control group (EP placebo + PENS placebo + ET); Percutaneous Electrolysis (EP - placebo) + Percutaneous Electrical Nerve Stimulation (PENS - placebo) + Therapeutic Exercise (ET)	Procedure: EP placebo + PENS placebo + ET; Percutaneous Electrolysis (EP - placebo) + Percutaneous Electrical Nerve Stimulation (PENS - placebo) + Therapeutic Exercise (ET)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain Intensity	The Numerical Pain Rating Scale (NPRS) will be used to estimate pain intensity. This scale assigns a number between 0 (no pain) and 10 (worst possible pain) (Farrar et al., 2001). Using this instrument, the patient will rate the intensity of the pain they feel at the worst time of day and the average level of pain experienced over the past week. This easy-to-complete, quick, and simple scale has shown a Minimal Detectable Change (MDC) of 1.3 to 2.8 points in patients with musculoskeletal problems and 1.7 points in subacromial pain syndrome.	- Baseline (T0) - 4 initial weeks - (T1) - 12 initial weeks - (T2) - 24 initial weeks - (T3)
Pressure Pain Threshold (PPT)	The test will be performed using a mechanical pressure algometer at specific study points to determine the amount of pressure applied at which the sensation of pressure changes to pain. The patient will be seated in a comfortable and relaxed position. The procedure consists of applying the tip of the algometer perpendicular to the skin and maintaining a pressure that will be progressively increased until the pain threshold is reached. Subjects will be instructed to signal when this pressure pain threshold (PPT) is exceeded. The physiotherapist will take three measurements, with a 30-second rest period between each measurement, calculating the average value in kg.. Measurements will be taken on the affected side, in the subacromial space region (treatment area), in the upper trapezius muscle (midpoint between the neck and shoulder muscle fibers), in the ventral part of the middle head of the deltoid muscle (segmental area), and in the tibialis anterior muscle,	- Baseline (T0) - 4 initial weeks - (T1) - 12 initial weeks - (T2) - 24 initial weeks - (T3)
Function	The Constat-Murley (CM) questionnaire is a commonly used, specific instrument for assessing overall shoulder joint function (Roy et al., 2010). The maximum score is 100 points, with 90 to 100 considered excellent, 80 to 89 good, 70 to 79 fair, and below 70 poor, although scores may vary with age. This tool includes a subjective assessment of the patient's pain and ability to perform daily activities (35 points), and an objective assessment of mobility and strength through physical examination (65 points). Its use has been specifically validated in shoulder arthroplasty, rotator cuff repair, adhesive capsulitis, and proximal humerus fractures. This tool has shown a Minimal Detectable Change (MDC) of 11.6 points in patients with subacromial impingement.	- Baseline (T0) - 4 initial weeks - (T1) - 12 initial weeks - (T2) - 24 initial weeks - (T3)
Disability	The Shoulder Pain and Disability Index (SPADI) focuses on the degree of pain or disability caused by shoulder problems during the past week. It is a self-administered questionnaire consisting of two dimensions: one for pain and one for functional activities. The pain dimension comprises five questions about the severity of pain. Functional activities are assessed with eight questions, designed to measure the degree of difficulty a person has performing various activities of daily living that require the use of the upper extremities. The patient answers the questions using a visual analog scale (from 0 to 10), both in the pain dimension (0 equals no pain and 10 equals the worst pain imaginable) and in the disability dimension (0 equals no difficulty and 10 equals so difficult that help was required). In patients with subacromial pain syndrome, this questionnaire has shown a Minimal Detectable Change (MDC) of 20.5 points.	- Baseline (T0) - 4 initial weeks - (T1) - 12 initial weeks - (T2) - 24 initial weeks - (T3)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall Perception of Clinical Change	The overall change rating will be obtained using an 11-point scale, used to estimate the clinical change perceived by the patient. Participants will be asked to rate the overall perceived change in their shoulder pain condition, from the start of the study to the present, based on three possible options: worse, no change, or better. If participants indicate worse, they will be asked how much worse on a 5-point scale (from much worse to slightly worse). Similarly, if participants indicate better, they will be asked how much better on a 5-point scale (from slightly better to much better). The minimum clinically significant change is 2 points.	- Baseline (T0) - 4 initial weeks - (T1) - 12 initial weeks - (T2) - 24 initial weeks - (T3)
Kinesiophobia	The Tampa Scale for Kinesiophobia (TSK-11) is a widely used instrument to assess fear of movement or re-injury. The abbreviated version is the most common in current clinical practice and consists of 11 items, to which the patient responds on a 4-point Likert scale, indicating their level of agreement with the statements. The range is from 11 to 44 points (minimal: ≤ 22 points; low: 23-28 points; moderate: 29-35 points; and high: ≥ 36 points). The resulting instrument demonstrates good reliability (internal consistency and stability) and validity (convergent and predictive), with the advantage of its brevity. A high score indicates extreme fear of movement, while a low score indicates insignificant fear of movement. This scale has been used in various clinical contexts, especially to assess fear of movement in patients with chronic musculoskeletal pain, including shoulder pain.	- Baseline (T0) - 4 initial weeks - (T1) - 12 initial weeks - (T2) - 24 initial weeks - (T3)
Perceived self-efficacy with pain	A 10-item Pain Self-Efficacy Questionnaire will be used to assess patients' confidence in performing daily activities while experiencing pain, in this case, shoulder pain. The Pain Self-Efficacy Questionnaire (PSEQ-10) is a reliable and valid tool for the point assessment of self-efficacy in people with chronic shoulder pain (Medina et al., 2025). Findings suggest a moderate association between pain self-efficacy, chronic shoulder pain, and disability. This variable is considered to modulate the results after treatment, and even has implications for patients' functioning in their daily lives.	- Baseline (T0) - 4 initial weeks - (T1) - 12 initial weeks - (T2) - 24 initial weeks - (T3)
Adherence to the exercise program	Adherence to the prescribed exercise program will be assessed using, on the one hand, an exercise diary documenting the completion of scheduled sessions and, on the other hand, the Exercise Adherence Rating Scale (EARS). This is a 6-item instrument designed for this purpose. The items are scored using an ordinal response scale (from 0 = strongly agree to 4 = strongly disagree). The six items are summed, and items with positive statements (items 1, 4, and 6) are scored in reverse. Higher scores indicate greater adherence (0 to 24). The scale would be completed at the end of the intervention (12 weeks) and at the end of the follow-up period. The exercise session diary will allow for the calculation of the percentage of training sessions completed by the subject in each intervention group. Regarding the total number of sessions between T0 and T3 (36 sessions - 3 sessions per week, for 12 weeks). A minimum of 12 completed sessions, equivalent to 4 weeks of in	- Baseline (T0) - 4 initial weeks - (T1) - 12 initial weeks - (T2) - 24 initial weeks - (T3)

Collaborators and Investigators

• Sponsor: Universidad Miguel Hernandez de Elche
• Investigators: Principal Investigator: José-Vicente Toledo-Marhuenda, Ph D, Miguel Hernández University. Faculty of Medicine

Publications and helpful links

General Publications

• Arias-Buria JL, Cleland JA, El Bachiri YR, Plaza-Manzano G, Fernandez-de-Las-Penas C. Ultrasound-Guided Percutaneous Electrical Nerve Stimulation of the Radial Nerve for a Patient With Lateral Elbow Pain: A Case Report With a 2-Year Follow-up. J Orthop Sports Phys Ther. 2019 May;49(5):347-354. doi: 10.2519/jospt.2019.8570. Epub 2019 Jan 18.
• Augustyn D, Paez A. The effectiveness of intratissue percutaneous electrolysis for the treatment of tendinopathy: a systematic review. S Afr J Sports Med. 2022 Jan 1;34(1):v34i1a12754. doi: 10.17159/2078-516X/2022/v34i1a12754. eCollection 2022.
• Arulkumar S,Neuchat EE,Ly E,Ly AI,Fahimipour K,Desai MJ
• Arias-Buría JL,Truyols-Domínguez S,Valero-Alcaide R,Salom-Moreno J,Atín-Arratibel MA,Fernández-de-Las-Peñas C
• Albright-Trainer B, Phan T, Trainer RJ, Crosby ND, Murphy DP, Disalvo P, Amendola M, Lester DD. Peripheral nerve stimulation for the management of acute and subacute post-amputation pain: a randomized, controlled feasibility trial. Pain Manag. 2022 Apr;12(3):357-369. doi: 10.2217/pmt-2021-0087. Epub 2021 Nov 11.
• Albert-Lucena D, Navarro-Santana MJ, Lopez-de-Uralde-Villanueva I, Diaz-Arribas MJ, Valera-Calero JA, Fernandez-de-Las-Penas C, Plaza-Manzano G. Immediate effects of percutaneous electrical nerve stimulation in patients with lateral elbow pain. Physiother Theory Pract. 2024 Dec;40(12):2783-2794. doi: 10.1080/09593985.2023.2296063. Epub 2023 Dec 26.
• Abat F, Valles SL, Gelber PE, Polidori F, Stitik TP, Garcia-Herreros S, Monllau JC, Sanchez-Ibanez JM. [Molecular repair mechanisms using the Intratissue Percutaneous Electrolysis technique in patellar tendonitis]. Rev Esp Cir Ortop Traumatol. 2014 Jul-Aug;58(4):201-5. doi: 10.1016/j.recot.2014.01.002. Epub 2014 May 10. Spanish.
• Abat F,Sánchez-Sánchez JL,Martín-Nogueras AM,Calvo-Arenillas JI,Yajeya J,Méndez-Sánchez R,Monllau JC,Gelber PE
• Abat F,Diesel WJ,Gelber PE,Polidori F,Monllau JC,Sanchez-Ibañez JM

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: March 18, 2026
• First Submitted That Met QC Criteria: March 25, 2026
• First Posted (Actual): March 27, 2026

Study Record Updates

• Last Update Posted (Actual): March 27, 2026
• Last Update Submitted That Met QC Criteria: March 25, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Chronic pain; Therapeutic exercise; Percutaneous Electrical Nerve Stimulation; Percutaneous Electrolysis; Shoulder tendinopathy
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Chronic Pain
• Other Study ID Numbers: JVT004

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

IPD Plan Description

To conduct the study, project registration will be requested from the Ethics and Research Committee of the Dr. Balmis University General Hospital of Alicante. The data collected will be used exclusively for the described study and will not be shared with any other healthcare provider. Each patient will be informed of the data to be collected and the purpose for which it will be used, and will have the right to access, modify, object to, cancel, port, and limit the processing of their data at any time.

In accordance with the principles of the Spanish Organic Law on the Protection of Personal Data, the identification of participants will be protected with a unique study identification number, which will be electronically recorded in a separate database to safeguard confidentiality. The file will be stored with double password protection. Therefore, it will not be necessary to register the file with the Spanish Data Protection Agency.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No