Biologic and synthetic ligament reconstructions achieve better functional scores compared to osteosynthesis in the treatment of acute acromioclavicular joint dislocation.

To systematically review the outcomes of surgical treatments of acute acromioclavicular joint dislocation. Studies were identified by electronic databases (Ovid, PubMed). All studies reporting functional and radiological outcomes of surgical treatments of acute acromioclavicular joint dislocations were included. Following data were extracted: authors and year, study design, level of evidence, number of patients, age, classification of acromioclavicular joint dislocation, time to surgery, surgical technique, follow-up, clinical and imaging outcomes, complications, and failures. Descriptive statistics was used, when a data pooling was not possible. Comparable outcomes were pooled to generate summary outcomes reported as frequency-weighted values. Quality appraisal was assessed through the MINORS checklist. One hundred and thirty-three studies were included for a total of 4473 shoulders. Mean age of participants was 36.9 years. Mean follow-up was 42.06 months. Arthroscopy showed better ASES (p < 0.0001) and lower VAS pain score (p = 0.0249) compared to an open approach. Biologic and synthetic reconstructions demonstrated better results over osteosynthesis techniques. Biologic techniques showed overall better Constant (p = 0.0001) and DASH (p = 0.0215) scores, while synthetic reconstruction showed better UCLA score (p = 0.0001). Among suture buttons, triple button showed overall better results in Constant (p = 0.0001) and VAS (p = 0.0001) scores, while better results in DASH score (p = 0.0003) were achieved by 2 double button techniques. Overall, the level of evidence was low. Biological and synthetic reconstructions achieved better functional scores compared to osteosynthesis. Among suture buttons, the triple button showed better functional performance. IV.