• PURPOSE
    • To perform a systematic review of the available literature on clinical and radiographic outcomes after surgical treatment for acromioclavicular (AC) joint instability.
  • METHODS
    • A systematic review was performed according to PRISMA guidelines. Inclusion criteria were AC joint and coracoclavicular (CC) ligament reconstruction outcomes, English language, human studies, more than 10 patients in the study and a 2-year minimum follow-up. Exclusion criteria were animal studies, cadaveric studies, clinical studies without reported follow-up period or patient-reported outcomes, clinical studies of nonoperative treatment, AC reconstructions with concurrent lateral clavicle fracture, editorial articles, abstracts, presentations, reviews, case reports, and surveys.
  • RESULTS
    • The systematic review identified 34 studies (939 patients) after inclusion and exclusion criteria application. Postoperative American Shoulder and Elbow Surgeons (ASES) scores ranged from 93.8 to 96, 81.8 to 97.8, and 88.1 for free tendon graft, suspensory devices, and modified Weaver-Dunn techniques, respectively. Postoperative Constant scores were 76.4 to 96.0, 82.6 to 97.8, 85.9 to 97.0, 81 to 96 and 83.0 to 94.6 for free tendon graft, suspensory devices, synthetic ligament devices, modified Weaver-Dunn, and hook plate/K-wires techniques, respectively. All treatment modalities improved patient outcomes; however, hook plates and K-wires had the highest rate of complications (26.3%). Unplanned reoperation rates were 1.2%, 2.8%, 0.9%, 5.4%, and 2.6% in free tendon graft, suspensory devices, synthetic ligament devices, modified Weaver-Dunn, and hook plate/K-wires techniques, respectively.
  • CONCLUSIONS
    • Comparable subjective outcomes after surgical treatment of AC joint instability was reported for all modalities, with relatively low unplanned reoperation rates. Treatment with hook plate/K-wires was associated with the highest complication rates, and modified Weaver-Dunn had the highest unplanned reoperation rates. LEVEL OF EVIDENCE: Level IV, systematic review of Level I-IV studies.