Evaluation of Inadequate Response to Ultrasound-Guided Subacromial Corticosteroid Injection in Shoulder Impingement Syndrome

Evaluation of Inadequate Response to Ultrasound-Guided Subacromial Corticosteroid Injection in Shoulder Impingement Syndrome: Treatment Failure or Central Sensitization?

The aim of this study is to investigate the impact of central sensitization in patients with shoulder impingement syndrome who have shown an inadequate response to ultrasound-guided subacromial corticosteroid injection. Additionally, the patients' pain perception and emotional state will be evaluated, and the relationships between these factors and the treatment response will be analyzed.

Seventy-two patients aged 18-75, who applied to the Physical Therapy and Rehabilitation outpatient clinic at Beylikdüzü State Hospital, diagnosed with shoulder impingement syndrome based on magnetic resonance imaging (MRI), and who received ultrasound-guided corticosteroid injection, will be included in the study. No additional interventions or procedures will be performed for the research. These patients, who were previously assessed and treated in the outpatient clinic, will be invited for a follow-up examination at the 4th week after the injection. During the follow-up, their response to the treatment will be evaluated using the Visual Analog Scale (VAS). A reduction of less than 50% on the VAS by the end of the 4th week will be considered an inadequate response. Patients with inadequate and good responses will be divided into two groups and assessed for central sensitization, pain perception, and emotional state. Central sensitization will be evaluated using the Central Sensitization Inventory (CSI), and hyperalgesia will be assessed using an algometer to measure pressure-pain threshold. Additionally, the Pain Catastrophizing Scale and the Hospital Anxiety and Depression Scale will be used to determine the patients' emotional state and pain perception.

Inclusion Criteria:

• Patients aged 18-65.
• Diagnosed with shoulder impingement syndrome.
• Received ultrasound-guided subacromial corticosteroid injection.
• Experienced shoulder pain for at least 6 months.

Exclusion Criteria:

• History of surgery or fracture in the shoulder or related areas.
• Presence of an active infection.
• Received shoulder injection within the last 6 months.
• Underwent physical therapy for the shoulder in the last 6 months.
• Presence of other musculoskeletal or neurological conditions that could cause shoulder pain (e.g., cervical disc herniation, stenosis, moderate to severe osteoarthritis, adhesive capsulitis, rheumatologic pathologies, infectious joint diseases).