Background: Acromioclavicular (AC) joint dislocations account for 12% of shoulder girdle injuries. While endobutton fixation provides vertical stability in Rockwood type III and V dislocations, augmentation with suture anchors may improve overall fixation, reducing complications and improving outcomes.

Objectives: This study prospectively evaluates functional and radiological outcomes following combined endobutton and suture anchor fixation in patients with acute Rockwood III and V AC joint dislocations, assessing shoulder function and complication profiles at 12 months postoperatively.

Methods: Fifteen patients (9 females, 6 males) with acute (<7 days) Rockwood III/V dislocations underwent surgery using a double endobutton construct reinforced with a suture anchor. Mean age was 46.9 ± 11.1 years. Outcomes were measured using the Constant-Murley Score (CMS), American Shoulder and Elbow Surgeons (ASES) score, Visual Analog Scale (VAS) for pain, Simple Shoulder Test (SST), and Acromioclavicular Joint Instability (ACJI) score before surgery and at 12 months post-op. Radiological evaluation assessed reduction maintenance. Statistical analysis utilized paired t-tests and Wilcoxon signed-rank tests.

Results: Using Wilcoxon signed-rank test, significant improvements were observed in CMS (p < 0.001), ASES (p < 0.001), VAS (p = 0.001), and SST (p = 0.006) scores at 12 months postoperatively. The ACJI score showed a non-significant change (p = 0.095). Radiological reduction was maintained in 66.7% (10/15) patients; complications included no issues in 53.3%, residual pain in 20%, and stiffness in 26.7%.