Minimally Invasive Coracoclavicular Ligament Reconstruction With a Flip-Button Technique (MINAR): Clinical and Radiological Midterm Results

Background: Acromioclavicular (AC) joint dislocation is a frequent injury in sports. Hypothesis: A minimally invasive flip-button technique, MINAR (minimally invasive acromioclavicular joint reconstruction), will achieve good clinical and radiographic results in the surgical treatment of high-grade AC joint dislocations. Study Design: Case series; Level of evidence, 4. Methods: In this study, 96 patients with AC joint dislocation grades III through V and minimally invasive flip-button repair were identified. Radiographic assessment was performed by use of the Alexander view and by anteroposterior stress radiograph. Clinical outcomes were assessed with the Constant and Taft scores. Factors that influenced outcomes, such as age, time from trauma to surgery, and degree of dislocation, were evaluated. Results: Of the 96 patients, 83 (86.4%; 3 women and 80 men) were able to participate in clinical and radiographic follow-up. The average age of the participants was 39 years (range, 17-80 years). At a mean follow-up of 39 months (range, 12-78 months), clinical assessment revealed excellent results with a mean Constant score of 94.7 (range, 61-100). Clinical and radiological assessment using the Taft score also showed excellent results, with a mean score of 10.8 (range, 3-12). The mean time period from trauma to surgery was 6 days (range, 0-22 days), and mean duration of surgery was 48 minutes (range, 24-98 minutes). Nine patients (10.8%) underwent revision surgery due to recurrent dislocation (n = 8) or wound infection (n = 1). Radiological assessment showed that 18 patients had sustained a loss of reduction defined as subluxation of 50% of the clavicle shaft width in the vertical plane. However, there was no significant correlation (P = .254) with clinical outcome. Patient age was a relevant factor influencing outcome, as significantly higher outcome values were detected for younger patients (P = .024). No significant influence was shown for the time period from trauma to surgery (P = .336) or degree of dislocation after trauma (P = .987). Conclusion: The MINAR technique is a safe procedure and achieves good to excellent clinical and radiographic results in the surgical treatment of high-grade AC joint dislocations. Despite the simplicity of this technique, the surgeon has to overcome the learning curve to minimize the risk of recurrent dislocation.