Proprioceptive Neuromuscular Facilitation vs Conventional Therapy With Ultrasound-Guided Corticosteroid Injections for Subacromial Bursitis

• Ultrasound-Guided Corticosteroid Injections plus PNF (Drug): Participants in this group receive a combined interventional and rehabilitative treatment. Initially, all patients undergo a cycle of three ultrasound-guided subacromial corticosteroid injections (metilprednisolone 40 mg) administered once weekly to reduce inflammation and pain. Following the injection phase, participants complete a structured physiotherapy program based on Proprioceptive Neuromuscular Facilitation (PNF), consisting of supervised sessions aimed at improving shoulder mobility, muscle strength, coordination, and neuromuscular control through specific movement patterns and facilitation techniques.
• Ultrasound-Guided Corticosteroid Injections plus Conventional Physiotherapy (Drug): Participants in this group receive a combined interventional and rehabilitative treatment. Initially, all patients undergo a cycle of three ultrasound-guided subacromial corticosteroid injections (metilprednisolone 40 mg) administered once weekly to reduce inflammation and pain. Following the injection phase, participants complete a conventional physiotherapy program consisting of supervised sessions including passive and active mobilization exercises, muscle strengthening, stretching, and proprioceptive training aimed at improving shoulder mobility, function, and overall physical performance.

Primary outcomes

• Pain intensity measured by the Numeric Rating Scale (NRS) [Baseline, 2 weeks, 1 month, 3 months, and 6 months]: Pain intensity was assessed using the Numeric Rating Scale (NRS), ranging from 0 (no pain) to 10 (worst imaginable pain), where higher scores indicate greater pain. Patients rated their average pain over the previous 24 hours at each timepoint (baseline and follow-up).

Secondary outcomes

• Upper limb function (DASH) [Baseline, 2 weeks, 1 month, 3 months, and 6 months]: Upper limb function was assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, a self-reported measure ranging from 0 to 100, where higher scores indicate greater disability. Participants completed the questionnaire at baseline and follow-up timepoints.
• Health-related quality of life (EQ-5D-3L Index) [Baseline, 2 weeks, 1 month, 3 months, and 6 months]: Health-related quality of life was assessed using the EuroQol 5 Dimensions 3 Levels (EQ-5D-3L) Index, ranging from values below 0 (health states worse than death) to 1 (full health), where higher scores indicate better health status. The index was derived from patient responses to the EQ-5D-3L descriptive system at each assessment timepoint.
• Perceived health status (EQ-VAS) [Baseline, 2 weeks, 1 month, 3 months, and 6 months]: Perceived health status was assessed using the EuroQol Visual Analogue Scale (EQ-VAS), ranging from 0 (worst imaginable health) to 100 (best imaginable health), where higher scores indicate better perceived health. Patients self-reported their health status at each assessment timepoint.
• Shoulder Range of Motion (ROM) [Baseline, 2 weeks, 1 month, 3 months, and 6 months]: Shoulder range of motion was assessed using a goniometer, measuring active movements (flexion, abduction, and external rotation) in degrees. Higher values indicate better joint mobility. Measurements were performed at each assessment timepoint.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Adults aged ≥ 18 years
* Diagnosis of chronic shoulder pain (duration ≥ 3 months)
* Pain intensity ≥ 4 on the Numeric Rating Scale (NRS)
* Body Mass Index (BMI) < 30 kg/m²
* Ability to understand and provide written informed consent

Exclusion Criteria:

* Severe cognitive impairment (Mini-Mental State Examination < 24) or inability to provide informed consent
* Severe cardiovascular or cerebrovascular diseases
* History of neurological or psychiatric disorders
* Active oncological disease
* Rheumatoid arthritis
* Previous shoulder arthroplasty
* Severe osteoporosis
* Use of oral analgesics, intra-articular injections, physiotherapy, or physical therapies within 15 days prior to enrollment;

• Study Protocol and Statistical Analysis Plan (PDF, 2026-03-22)