PEMF Therapy in Shoulder Tendinopathy

Shoulder tendinopathies are a common cause of pain, functional limitation, and reduced quality of life, with a significant impact on daily activities. Their clinical presentation is heterogeneous, involving not only structural and functional impairments but also activity limitations and participation restrictions.

Conservative management remains the first-line approach and typically includes multimodal rehabilitation programs incorporating balneophysiotherapy, exercise therapy, and physical modalities. Although these interventions are widely used and have demonstrated clinical benefits, the optimal combination of therapeutic modalities remains a subject of ongoing research.

Pulsed electromagnetic field (PEMF) therapy delivered via the Super Inductive System (SIS) is a non-invasive intervention with potential analgesic, neuromodulatory, and regenerative effects. However, evidence regarding its additional benefit when integrated into standard multimodal rehabilitation programs for shoulder tendinopathies is still limited.

Given the multifactorial nature of shoulder tendinopathies, a multidimensional assessment approach is required. This study is based on the framework of the International Classification of Functioning, Disability and Health (ICF) and aligned with OMERACT recommendations, allowing a comprehensive evaluation of clinical outcomes across multiple domains.

The aim of this study is to compare the effectiveness of PEMF therapy delivered via SIS, integrated into a multimodal rehabilitation program, with standard balneophysiotherapy in patients with shoulder tendinopathies.

Participants are allocated to either a control group receiving standard treatment or an experimental group receiving the same rehabilitation program supplemented with PEMF (SIS) therapy. Clinical outcomes, including pain intensity, shoulder function, pressure pain threshold, muscle strength, psychological status, depressive symptoms, and quality of life, are assessed at three time points: T0 (baseline, at admission), T1 (immediately after completion of the 10-day treatment program), and T2 (3 months after treatment completion). The follow-up assessment aims to evaluate the maintenance of therapeutic effects over time.

This study seeks to determine whether the addition of PEMF (SIS) therapy provides superior outcomes within a multimodal rehabilitation strategy and supports a personalized, multidimensional approach to the management of shoulder tendinopathies.

• Nanopulsed Electromagnetic Field Therapy (SIS) (Device): Nanopulsed electromagnetic field therapy is delivered using the Super Inductive System (SIS) device applied to the affected shoulder. The intervention is administered daily over a two-week period, with a total of 10 sessions. Each session lasts approximately 10-15 minutes. The therapy delivers high-intensity electromagnetic pulses with adjustable frequency and intensity, aiming to reduce pain, stimulate tissue regeneration, and improve functional outcomes.
• Balneophysiotherapy (Other): The intervention is based on the region's specific natural therapeutic resources and is conducted under continuous medical supervision. The treatment program includes saline therapeutic baths combined with exercise therapy and applications of sapropelic therapeutic mud, administered daily over a two-week period, five days per week. In addition, patients receive electrotherapy according to a standardized protocol, including magnetotherapy, interferential current therapy, and therapeutic ultrasound. The rehabilitation program also incorporates massage therapy and individualized therapeutic exercises.

Primary outcomes

• Pain intensity assessed by Visual Analog Scale (VAS) [Baseline (T0), immediately after the 10-day treatment period (T1), and 3 months after treatment completion (T2).]: Pain intensity will be measured using the Visual Analog Scale (VAS). Participants were asked to rate their current pain intensity by marking a point on a 100-mm horizontal line, where 0 indicates "no pain" and 100 indicates "worst pain imaginable." The score was recorded in millimeters (mm). Outcome range and interpretation: Minimum value: 0; Maximum value: 100. Higher scores indicate worse pain intensity.

Secondary outcomes

• Shoulder function assessed by Shoulder Pain and Disability Index (SPADI) [Baseline (T0), immediately after the 10-day treatment period (T1), and 3 months after treatment completion (T2).]: Shoulder pain and disability were assessed using the Shoulder Pain and Disability Index (SPADI), a self-administered questionnaire consisting of two domains: pain (5 items) and disability (8 items). Each item is scored on a scale from 0 to 10, with higher scores indicating greater pain and functional impairment. The total SPADI score is expressed as a percentage (0-100%).
• Pressure Pain Threshold (PPT) assessed by digital algometry [Baseline (T0), immediately after the 10-day treatment period (T1), and 3 months after treatment completion (T2).]: Pressure pain threshold will be measured using a digital algometer at standardized anatomical points of the shoulder. The mean value of repeated measurements will be recorded.
• Range of motion (ROM) assessed by goniometry [Baseline (T0), immediately after the 10-day treatment period (T1), and 3 months after treatment completion (T2).]: Active range of motion of the shoulder (flexion, abduction, external rotation, internal rotation) will be measured using a goniometer.
• Muscle strength assessed by dynamometry [Baseline (T0), immediately after the 10-day treatment period (T1), and 3 months after treatment completion (T2).]: Shoulder muscle strength was assessed using a handheld dynamometer. Measurements were performed for key shoulder movements, and values were recorded in kilograms. Higher values indicate greater muscle strength.
• Psychological status assessed by Hospital Anxiety and Depression Scale (HADS) [Baseline (T0), immediately after the 10-day treatment period (T1), and 3 months after treatment completion (T2).]: Psychological status was assessed using the Hospital Anxiety and Depression Scale (HADS), which consists of 14 items divided into two subscales: anxiety (HADS-A) and depression (HADS-D), each containing 7 items. Participants rated how they had been feeling over the previous week. Each item is scored on a 4-point Likert scale ranging from 0 to 3. Subscale scores were calculated by summing the relevant item scores and are reported as unitless values. Outcome range and interpretation: HADS-A (Anxiety): Minimum value: 0; Maximum value: 21. Higher scores indicate greater anxiety severity. HADS-D (Depression): Minimum value: 0; Maximum value: 21. Higher scores indicate greater depressive symptom severity.
• Depression severity assessed by Patient Health Questionnaire-9 (PHQ-9) [Baseline (T0), immediately after the 10-day treatment period (T1), and 3 months after treatment completion (T2).]: Depression severity will be assessed using the Patient Health Questionnaire-9 (PHQ-9), a self-administered questionnaire consisting of 9 items scored from 0 to 3. Total scores range from 0 to 27, with higher scores indicating greater severity of depressive symptoms.
• Quality of life assessed by EQ-5D-5L [Baseline (T0), immediately after the 10-day treatment period (T1), and 3 months after treatment completion (T2).]: Quality of life was assessed using the EQ-5D-5L questionnaire, which evaluates five dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension has five levels of severity. Higher scores indicate poorer quality of life.

Sex: All, ages: 18 Years to 70 Years

Inclusion Criteria:

* Adults aged between 18 and 70 years.
* Patients with chronic shoulder pain lasting more than 3 months, of non-traumatic origin, persistent despite prior conservative treatment.
* Clinical diagnosis of shoulder tendinopathy and/or subacromial pain syndrome based on medical history and physical examination.
* Presence of shoulder pain and functional limitation confirmed by clinical assessment and baseline functional evaluation (SPADI).
* Ability to comply with the treatment protocol and attend scheduled follow-up assessments.
* Provision of written informed consent prior to participation.

Exclusion Criteria:

* Full-thickness rotator cuff tears with surgical indication.
* Recent major shoulder trauma (within the last 6 months).
* Active systemic inflammatory or rheumatologic diseases.
* Presence of metallic implants in the treatment area or implanted electronic devices (e.g., pacemaker).
* Neurological disorders affecting the upper limb.
* Contraindications to balneotherapy (e.g., severe cardiovascular disease, renal failure, severe dermatological conditions).
* Decompensated chronic diseases at the time of enrollment (cardiovascular, hepatic, renal, respiratory, or neurological).
* Skin lesions at the site of treatment application.
* Pregnancy or breastfeeding.
* Active neoplastic disease.
* Decompensated psychiatric disorders.
* History of hypersensitivity to natural therapeutic factors used in balneotherapy.
* Refusal to participate or inability to provide informed consent.

• Alexandra-Ecaterina Ciota, MD, Principal investigator, Balneal and Rehabilitation Sanatorium Techirghiol