Clinical Outcomes of Arthroscopy‐Assisted Modified Triple Endobutton Plate Fixation in Rockwood Type III Acute Acromioclavicular Joint Dislocation: A Retrospective Study

OBJECTIVE: The common triple Endobutton plate (CTEP) fixation is a lengthy procedure that is associated with high failure rates. Therefore, we used arthroscopy to improve the Endobutton fixation method by shortening the duration of surgery and reducing operative complications. This study explored the safety and effectiveness of arthroscopy‐assisted modified triple Endobutton plate (MTEP) fixation in Rockwood type III managing acute acromioclavicular joint (ACJ) dislocation. METHODS: This was a retrospective single‐center study involving 73 patients with Rockwood type III acute ACJ dislocation treated between January 2016 and January 2021. The 73 patients were classified into three groups, the acromioclavicular hook plate (ACHP) group (22 cases), CTEP group (24 cases) and MTEP group (27 cases), based on the type of surgical treatment they received. Clinical outcome data from the patient records, including the Constant–Murley score (CMS), American Shoulder and Elbow Surgeons score (ASES) and University of California at Los Angeles shoulder rating scale score (UCLA), were retrospectively reviewed. The scores were assessed before surgery and at the third and twelfth month after surgery. The clavicle‐coracoid (CC) distance on the affected side was estimated from imaging scans taken before surgery, on the second day after surgery, and within the third and twelfth month after surgery. The student's t‐test was used to compare normally distributed data for independent samples, while homogeneity of variance test was used to compare normally distributed data among multiple groups. Non‐normally distributed data were compared using Mann–Whitney rank‐sum tests. RESULTS: There were no differences in age, gender, body mass index (BMI), dislocated side, trauma etiology, and duration of follow‐up among the three groups. There was also no significant difference in the duration of surgery between the ACHP and MTEP groups, although the duration in the two groups was shorter than in the CTEP group (P < 0.05). The duration of hospitalization for the MTEP group was significantly shorter than for the CTEP group which was in turn shorter than for the ACHP group (both P < 0.05). There was no significant difference in postoperative CMS, ASES, and UCLA scores between the CTEP and MTEP groups but the score for the two groups differed significantly from those of the ACHP group (all Ps < 0.05). In addition, there was no significant difference in CC distance among the three groups after surgery (P > 0.05). CONCLUSION: Arthroscopic reconstruction of the coracoclavicular ligament using MTEP fixation to manage acute Rockwood type III ACJ dislocation is minimally invasive, and is associated with rapid functional recovery, few complications and satisfactory early clinical results.