A Prospective Randomized Study Comparing Glenohumeral and Subacromial Corticosteroid Injections in the Management of Primary Frozen Shoulder

This prospective randomized comparative study evaluated the clinical efficacy of glenohumeral (GH) versus subacromial (SA) corticosteroid injections in managing primary frozen shoulder. The study was conducted at a tertiary care center in North India between 2023 and 2025. Sixty patients aged 20-70 years with stage 1 primary frozen shoulder, unresponsive to at least six weeks of conservative treatment, were included. Participants were randomly allocated to receive either a GH or SA injection containing triamcinolone, lidocaine, and saline. Each followed a standardized home-based exercise program. Outcomes were assessed at baseline and at 4, 8, and 12 weeks post-injection using the visual analogue scale (VAS), Constant-Murley score, and shoulder range of motion (ROM) parameters. These included forward (FWD) flexion, abduction, and internal and external rotation. Both GH and SA injections resulted in statistically significant improvements across all parameters over time (p < 0.0001). Comparative analysis revealed no significant difference between groups in pain relief, activities of daily living (ADLs), or internal rotation. However, GH injections showed significantly superior improvement in FWD flexion, abduction, and external rotation compared with SA injections. The findings suggest that both injection sites are effective for pain relief and functional improvement in primary frozen shoulder. Intra-articular GH injections may offer greater benefits for restoring specific shoulder movements, particularly those most affected by capsular fibrosis.