Comparison of the effects of ultrasound-guided suprascapular nerve block and intra-articular shoulder injection on pain, functional status and range of motion in patients with adhesive capsulitis: Randomized, controlled trial

Background Adhesive capsulitis (AC) is a common shoulder disorder. Ultrasound-guided intra-articular injection (IAI) and suprascapular nerve block (SSNB) are frequently used interventions for AC treatment; however, their comparative effectiveness remains unclear. Objective To compare the effects of SSNB and IAI on pain, functional status, and shoulder range of motion in patients with AC. Methods In this prospective, randomized, controlled, assessor-blinded trial, patients with AC were assigned to either ultrasound-guided IAI or SSNB. Both groups received the same injectable and a home-based exercise program. Outcome measures included the Shoulder Pain and Disability Index (SPADI), Visual Analog Scale (VAS), and passive shoulder ROM. Assessments were performed at baseline, on the 10th day, and at the 3rd month after treatment. ClinicalTrials.gov NCT05909462. Results Both groups showed significant improvements in pain, functional status, and shoulder range of motion over time (all p < 0.001). Compared with the IAI group, SSNB resulted in significantly greater improvements in SPADI Total and SPADI Disability scores, movement-related pain, shoulder flexion, and abduction at both the 10-day and 3-month follow-up assessments (all p < 0.05). In contrast, improvements in resting pain, shoulder extension, internal rotation, and external rotation were comparable between the groups. Conclusion Both ultrasound-guided IAI and SSNB were effective in the management of adhesive capsulitis. However, SSNB was associated with greater improvements in movement-related pain, shoulder function, and shoulder flexion and abduction, with these benefits maintained at both the early and mid-term follow-up assessments.