Double-button technique for the treatment of high degree AC-joint dislocations

Background: To evaluate clinical and radiological outcomes of Rockwood Type-V Acromioclavicular joint (AC-joint) dislocations, surgically treated with a double button device, within 5 days after trauma.

Methods: Eighty-six patients (80 males, 6 females) operated under radiological guidance with the Zip-Tight® fixation device were evaluated. The mean age of these patients was 37.9 years old (18-60). Radiological evaluation measuring Clavicle-coracoid (CC) distance was performed. Clinical evaluation was made by Acromioclavicular Joint Instability score (ACJI) and Simple Shoulder Test (SST).

Results: The average Follow-up (FU) was 24.2 months (12-32). The mean CC distance was 8.5 mm after surgery, and at the last FU it was 8.9 mm (not significant). Clinical outcomes at the last FU were; mean ACJI score: 84.7. Mean SST score: 11.5. Thirty-six patients (41.9%) present some degree of horizontal displacement of the clavicle (mean ACJI score: 73.5) and 50 patients (58.1%) did not present displacement (mean ACJI score: 95.2). This difference was statistically significant (p<0.001). There were no significant differences in either subjective (pain, tenderness, daily live activities and cosmesis) or in strength parameters between these groups.

Conclusion: The surgical treatment of high degree AC-joint dislocation using double-button device provides a stable fixation and satisfactory clinical and radiological results at intermediate-term FU.

Keywords: Acromioclavicular dislocation, double-button fixation, outcomes, shoulder surgery