Comparison of Clinical Outcomes Between Nonoperative Treatment and Arthroscopically Assisted Stabilization in Patients With Acute Rockwood Type 5 Acromioclavicular Dislocation

Background: Currently, Rockwood type 3 acromioclavicular (AC) joint dislocations are initially treated nonoperatively, whereas surgery is recommended for Rockwood type 5 dislocations. However, multiple studies have been published favoring nonoperative approaches in patients with high-grade Rockwood injuries. Purpose: To compare the clinical and radiological outcomes of patients with acute Rockwood type 5 AC joint dislocations treated nonoperatively versus with arthroscopically assisted stabilization. Study Design: Cohort study; Level of evidence, 3. Methods: Included were 48 patients with acute Rockwood type 5 dislocation who were initially treated nonoperatively between June 2010 and June 2022 and 48 patients matched according to age, sex, affected side, and follow-up interval who underwent arthroscopically assisted coracoclavicular (CC) stabilization using a suture-button technique, with additional percutaneous AC tape cerclage. Clinical outcomes were assessed based on the Subjective Shoulder Value, Nottingham Clavicle Score, Constant score, and visual analog scale for pain. The radiographic assessment included the CC distance, CC difference ratio, and degree of horizontal instability at final follow-up (62 ± 43 months). Results: At the final follow-up, the Constant score was significantly higher in the nonoperative group ( P = .02). The operative group had significantly higher pain levels on palpation of the AC joint (1.2 ± 2.2 vs 0.19 ± 0.5 for the nonoperative group; P = .003). In the operative group, the mean CC difference ratio was significantly higher at the latest follow-up compared with postoperatively (1.3 ± 0.3 vs 0.67 ± 0.3, respectively; P < .001), whereas the CC difference ratio of the nonoperative group was significantly reduced at the latest follow-up compared with postinjury (2.0 ± 0.5 vs 2.6 ± 0.8, respectively; P < .001). The operative group had a significantly lower CC difference ratio compared with the nonoperative group at final follow-up ( P < .001). More than half of the patients (56%) who were treated operatively had a loss of reduction resulting in a Rockwood type 3 state at the latest follow-up, whereas 54% of patients treated nonoperatively had spontaneous reduction of injury severity from Rockwood type 5 to Rockwood type 3. Conclusion: Although 15% of the nonoperatively treated patients eventually required surgery, successful nonoperative treatment showed similar outcomes to initial operative treatment in patients with acute Rockwood type 5 dislocation.