Abstract
BACKGROUND: Acromioclavicular (AC) joint dislocations are common in young, active adults, and restoring both vertical and horizontal stability remains a challenge. Although the single-button technique provides effective coracoclavicular (CC) fixation, its ability to maintain horizontal stability is limited. This study aimed to compare the clinical and radiological outcomes of the single- and double-button fixation techniques in the surgical management of acute AC joint dislocations. METHODS: A retrospective comparative study was conducted on 43 patients (21 single-button, 22 double-button) with Rockwood type III and V AC joint dislocations treated between 2017 and 2021. Radiological evaluation included CC and AC distance measurements on standardized Zanca and Alexander radiographs. Functional assessment was performed using the Constant-Murley and DASH scores at a minimum follow-up of six months. Complications were also recorded. Statistical analysis was performed using independent-sample t-tests and Fisher's exact test, with p < 0.05 considered significant. RESULTS: Postoperative CC distance difference was 0.29 ± 0.47 mm in the double-button group and 2.09 ± 1.52 mm in the single-button group. Postoperative AC distance difference was 0.87 ± 0.73 mm and 4.31 ± 1.65 mm, respectively. These differences were statistically significant (p = 0.001 and p < 0.001). Constant and DASH scores were comparable between groups (p > 0.05). Although overall complication rates did not differ significantly, arthrosis and implant failure were observed more frequently in the single-button group. CONCLUSION: The double-button technique demonstrated superior radiological vertical and horizontal stability compared with the single-button method, without compromising functional outcomes at six months. These findings represent short-term radiological results, and further studies with longer follow-up are required to determine whether improved horizontal stability translates into better long-term joint function and degeneration. LEVEL OF EVIDENCE: Level III - Retrospective Comparative Study.