Suprascapular Nerve Block and Proprioception in Hemiplegic Shoulder Pain: A Randomized Controlled Study

Hemiplegic shoulder pain is one of the most common painful complications following stroke, with a reported prevalence ranging from 16% to 84%. Its etiology is multifactorial and primarily includes musculoskeletal pathologies such as adhesive capsulitis, bicipital tendinitis, subacromial bursitis, shoulder subluxation, and rotator cuff disorders. Pain that may be present even at rest or during passive movement, along with reduced shoulder range of motion, represents the leading clinical complaint. Therefore, the main goal of treatment is to reduce pain, increase joint range of motion, and consequently enhance participation in rehabilitation and functional capacity. Suprascapular nerve block is a widely used intervention to reduce pain and improve shoulder range of motion in patients with hemiplegic shoulder pain. Proprioceptive and nociceptive receptors embedded in the glenohumeral joint capsule and surrounding ligaments play a crucial role in joint stability, and the suprascapular nerve provides major innervation to these structures. Despite its widespread use to facilitate rehabilitation and improve outcomes, the effects of suprascapular nerve block on shoulder joint proprioception and the subsequent impact of potential proprioceptive changes on rehabilitation outcomes have not yet been investigated. This study is designed as a prospective, controlled, investigator-blinded, parallel-group clinical trial. Fourteen stroke patients aged 18-80 years with hemiplegic shoulder pain will be enrolled and randomized into two groups. After baseline assessment (T0), one group will receive a suprascapular nerve block followed by a standardized physical therapy program, while the control group will receive the same physical therapy program alone. Follow-up assessments will be performed at 2 hours post-intervention (T1, intervention group only), at the end of the 3-week rehabilitation program (T2), and at week 7 (T3). The primary objective of this study is to evaluate the effect of suprascapular nerve block on shoulder joint proprioception in stroke patients with hemiplegic shoulder pain. Secondary objectives include assessing its effects on pain intensity, shoulder range of motion, post-stroke motor recovery, stroke-specific quality of life, and upper extremity physical function and symptoms. The null hypothesis is that suprascapular nerve block does not impair shoulder joint proprioception in patients with post-stroke hemiplegic shoulder pain.