The purpose of our study is to compare the radiographic and clinical outcomes with respect to acromioclavicular (AC) joint dislocation depending on the surgical method: Hook plate (HP) versus TightRope (TR).

Between May 2009 and May 2012, 51 patients with Rockwood type III-V lesions received clinical and radiographic follow-up. Patients were divided into two groups according to the surgical methods (HP: n=32; TR: n=19). Radiological follow-up included comparative coracoclavicular distance (CCD) measurements as a percentage of the uninjured shoulder. For clinical follow-up, a standardized functional shoulder assessment with the Constant score, University of California at Los Angeles (UCLA) score, and Korea shoulder score (KSS) were carried out.

Comparing the functional results, no differences were observed between the two groups (Constant score: HP, 78.5; TP, 81.4; UCLA score: HP, 29.2; TP, 29.9; KSS: HP, 79.2; TP, 80.7). Time to restoration of the range of motion (ROM) above shoulder level was longer in the HP group than in the TR group. However, the ROM at 1 year postoperation and final follow-up revealed similar results between the two groups. The AC joints were well reduced in both groups, the CCD increased to 44.7% in the HP group and to 76.5% in the TR group at the final follow-up; however, no one was significantly superior to the others. Furthermore, there were 8 cases (25.0%) and 5 cases (26.3%) of AC joint arthritis in the HP group and TR group, respectively. However, the observed AC joint arthritis has a poor correlation between clinical symptom and radiological results in both groups.

Both HP and TR fixation could be a recommendable treatment option in acute unstable AC joint dislocation. Both groups showed excellent radiologic and functional results at the final visit. Moreover, there was no significant difference in statistics, except for the time to restoration of ROM above shoulder level.