Aim: The aim of this study was to evaluate the effectiveness of endobutton coracoclavicular fixation in treating Rockwood Type III acromioclavicular joint disruptions by assessing pain reduction, shoulder function recovery, and complication rates. Materials and Methods: Five patients with chronic Type 3 Rockwood injury of the acromioclavicular joint, all with normal shoulder function pre-injury and aged over 18, were included. Each patient underwent preoperative evaluation with the Constant-Murley shoulder score and imaging (X-rays and MRI) to confirm injury type. Surgery was performed using a #5 first-generation Tight Ropeendobutton system under general anesthesia, with the clavicle secured to the coracoid process. Postoperative care included pain management and functional assessment at follow-up using the Constant-Murley score. Results: The sample consisted of three males (60%) and two females (40%), with 80% having left-sided injuries. The most common injury mechanism was trauma (60%). Outcome ratings indicated that 80% of patients achieved excellent results, with one case rated as good. Pain levels decreased significantly from a preoperative VAS mean of 5.0 ± 1.00 to 1.0 ± 0.00 (p = 0.001), while the Constant Murley score improved from a mean of 40 ± 3.29 preoperatively to 88 ± 1.87 at three months (p = 0.001). Only one patient developed adhesive capsulitis, while no cases of infection, implant breakage, or neurovascular injury were observed. Conclusion: Endobutton coracoclavicular fixation appears to be a safe and effective option for Rockwood Type III AC joint injuries, with significant pain reduction and functional improvement. Further large-scale studies are recommended to confirm these findings.