Chronic shoulder pain affects quality of life and is often associated with central sensitization, leading to treatment resistance. Pulsed radiofrequency (PRF) of the suprascapular nerve, which innervates 70% of the shoulder joint, is a promising therapy for nociceptive and neuropathic pain. This study evaluates the effects of PRF on central sensitization and neuropathic pain in chronic shoulder pain. Clinical assessments will be conducted at baseline, 1 month, and 3 months post-treatment to determine PRF's potential in reducing central sensitization and improving shoulder function.

Chronic shoulder pain is a prevalent musculoskeletal condition affecting quality of life, with an incidence of 18-26% in the general population. Its prevalence has doubled over the past 40 years. Pain sensitization, independent of etiology, is frequently observed in patients with musculoskeletal shoulder pain and can lead to poorer clinical outcomes even after primary disease treatment. Chronic pain development involves both peripheral and central sensitization mechanisms, with central sensitization characterized by amplified pain signaling and reduced inhibitory pathway activity. This can result in pain persistence independent of tissue damage and resistance to treatment.

Conventional treatments for chronic shoulder pain include physiotherapy, nonsteroidal anti-inflammatory drugs (NSAIDs), and intra-articular steroid injections. However, these may not provide sufficient long-term analgesia, and some patients develop treatment-resistant chronic pain. Recently, pulsed radiofrequency (PRF) treatment applied to the suprascapular nerve, responsible for 70% of the sensory innervation of the shoulder joint, has gained attention for its efficacy in reducing both nociceptive and neuropathic pain. PRF modulates neural activity without causing thermal damage and may have the potential to reduce central sensitization. However, its effects on central sensitization and neuropathic pain mechanisms remain insufficiently studied.

This study aims to evaluate the impact of suprascapular nerve PRF on central sensitization and neuropathic pain in chronic shoulder pain. Clinical assessments will be conducted at baseline, 1 month, and 3 months post-treatment to examine changes in central sensitization, neuropathic pain, and shoulder function. This study seeks to determine whether PRF can serve as an effective alternative in chronic shoulder pain management by reducing central sensitization and improving quality of life.

Inclusion Criteria:

• Chronic shoulder pain persisting for at least 3 months
• Radiologically confirmed shoulder lesions, including:

Rotator cuff tendinopathy Adhesive capsulitis Bursitis Osteoarthritis

• At least two positive provocation tests (Neer, Hawkins, Jobe tests)
• Shoulder pain resistant to conservative treatments, including:

Nonsteroidal anti-inflammatory drugs (NSAIDs) Physical therapy Corticosteroid injections

Exclusion Criteria:

• Traumatic shoulder pain (e.g., fractures, dislocations)
• History of shoulder surgery
• Active inflammation or rheumatic diseases affecting the shoulder, including:

Rheumatoid arthritis Polymyalgia rheumatica Ankylosing spondylitis

• Cervical radiculopathy
• Central nervous system diseases, such as:

Multiple sclerosis Stroke Spinal cord injury

Chronic shoulder pain persisting for at least 3 months