Comparison of hook plate alone, hook plate augmented with suture anchor, and arthroscopically-assisted tightrope fixation in the treatment of patients with acute type v acromioclavicular joint dislocations

INTRODUCTION: The best treatment for Rockwood type V acromioclavicular (AC) joint dislocation is unknown.

HYPOTHESIS: Hook plate augmented with suture anchor (HA) may have different clinical and radiological results than hook plate alone (H), and arthroscopically assisted TightRope (TR) techniques in treating acute type V AC joint dislocations.

MATERIAL AND METHODS: This retrospective study included 71 patients with acute type V AC joint dislocations between December 2010 and August 2018. Patients were categorized into three groups: H group (n=22), HA group (n=23) and TR group (n=26). We measured the coracoclavicular distance (CCD) differences and CCD ratio compared to uninjured side pre-operatively, immediately post-operatively, at 3-month and 2-year after operation. Clinical outcomes were assessed as well at the same time points. Loss of correction was determined by the CCD difference and ratio between surgical and uninjured sides.

RESULTS: The mean age and follow-up period were 41.8±24.7 years and 30.2±4.3 months, respectively. No significant differences were found in the demographic data between the three groups. The HA group presented a trend of less overcorrection but without significance compared with the H group at immediately post-operation, 3-month, and 2-year follow-up. (CCD difference: -2.4mm vs. -3.7mm, -1.6mm vs. -1.8, and 0.2mm vs -1.9mm, CCD ratio: 67.7% vs. 40.9%, 79.3% vs. 70.1%, and 100.6% vs. 86.5%, respectively). The HA group also had significantly less loss of correction compared with the TR group at 3-month and 2-year after the operation (CCD difference: -1.6mm vs. 1.6mm, 0.2mm vs. 2.4mm; CCD ratio: 79.3% vs. 122.2%, 100.6% vs. 136.1%, all p<0.05). All three methods achieved significant improvement in function and pain without inter-group differences. No coracoid-related or tunnel complications occurred.

DISCUSSION: The hook plate alone, and hook plate with suture anchor augmentation techniques provided less residual vertical instability compared to TightRope fixation at 2-year follow-up. The patient-reported functional outcomes were promising and comparable among the three groups.

LEVEL OF EVIDENCE: III, Retrospective comparative therapeutic trial.