Results from a US Investigational Device Study of Adhesive Capsulitis Embolization (ACE) in the treatment of Shoulder Pain: The ACE Study.

Purpose To evaluate the safety and efficacy of arterial embolization to relieve shoulder pain secondary to Adhesive Capsulitis (AC). Methods and materials 20 patients (18F, 2M: Mean age 51y) with AC resistant to > 30 days of conservative treatment were enrolled in a multi-center prospective study. Adhesive Capsulitis Embolization (ACE) was performed with 75 or 200 um spherical particles. Subjects were assessed before and after the procedure with MRI, VAS (0-100 mm), Single Assessment Numeric Evaluation (SANE, 0-100), and American Shoulder and Elbow Surgeons (ASES, 0-100) scores. Adverse Events (AEs) were recorded at all follow-up time points. Results Hypervascularity was identified and embolization was technically successful in all patients with 83 arteries embolized in 20 patients. Baseline VAS, SANE, and ASES scores before the procedure were 89.2 mm, 27.2, and 30.9 mm, respectively. 1 (n=19), 3 (n=18), and 6 (n=12) months follow-up demonstrated significant improvements: 1 mo VAS (Δ Mean = -31.8, p = 1.2E-11), SANE (Δ Mean = 22.1, p = 1.8E-8), and ASES (Δ Mean = 14.2, p = 4.3E-5): 6 mon VAS (Δ Mean = -62.1, p = 7.0E-11) SANE (Δ Mean = 55.4, p = 4.1E-10), and ASES (Δ Mean = 44.5, p = 1.8E-6). Due to the coronavirus pandemic, the study was ended early and six patients did not complete the 6-month follow-up. No major adverse events were noted. Conclusion Interim findings suggest that arterial embolization is safe and effective for patients with AC refractory to conservative treatment.