Abstract
Chronic shoulder pain is a common and multifactorial condition. Suprascapular nerve neuropathy, although relatively uncommon, may lead to pain, weakness, and muscle atrophy as a result of extrinsic compression, trauma, or inflammation. When it occurs in the presence of glenohumeral osteoarthritis, overall shoulder function may be further compromised, complicating both diagnostic assessment and therapeutic decision-making. We report the case of a 56-year-old man with a three-year history of chronic left shoulder pain and progressive proximal weakness, despite multiple courses of physiotherapy. His only relevant precedent trauma was a traumatic brain injury 20 years earlier. Physical examination revealed atrophy of the supraspinatus and infraspinatus muscles, reduced strength in lateral elevation and external rotation, and diffuse pain during shoulder maneuvers. Plain radiographs demonstrated glenohumeral osteoarthritis without evidence of significant rotator cuff arthropathy. Ultrasound imaging showed joint effusion, a paralabral cyst, and features of advanced osteoarthritis. Electroneuromyography revealed denervation of the supraspinatus and infraspinatus muscles, consistent with suprascapular neuropathy at the suprascapular notch. Glenohumeral arthrocentesis provided only transient symptomatic relief, and the patient was subsequently referred for orthopedic evaluation for potential reverse shoulder arthroplasty. This case highlights the importance of recognizing the potential interplay between suprascapular neuropathy and glenohumeral osteoarthritis in patients presenting with chronic shoulder pain. It also emphasizes the diagnostic value of integrated imaging and electrophysiological assessment to guide appropriate management and optimize patient outcomes.