What Outcome Measures Are Reported in the Management of Acromioclavicular Joint Injuries?

BACKGROUND: Lack of uniformity in reported outcomes makes comparisons between acromioclavicular joint (ACJ) injury studies challenging. Knowledge of common outcome measures and standardization will help orthopaedic surgeons report and compare outcomes more consistently. PURPOSE: To identify the most commonly reported outcome measures for ACJ injuries. STUDY DESIGN: Systematic review. METHODS: A systematic review was performed to identify all English-language original articles assessing any type of management of ACJ injuries (acute and chronic) in PubMed and Scopus from 2007 to 2017. Review articles, meta-analyses, studies with less than 5 patients, pediatric studies, technique articles, and biomechanical studies were excluded. The 100 top orthopaedic journals in the English literature were selected for review. Included studies were assessed for patient characteristics and the use of outcome variables, including range of motion (ROM), strength, patient-reported outcomes (PROs), satisfaction, return to work, return to sport, and complications. RESULTS: A total of 605 unique articles were identified; 92 met the inclusion criteria. The average number of ACJ injuries per study was 37, with a mean weighted patient age of 36 years (range, 20.1-57.3 years). The mean follow-up was 36 months (range, 5-290 months). Acute injuries were reported in 59% of studies. ROM and strength measurements were reported in 22.8% and 5.4% of studies. Sixteen different PRO instruments were used. The most commonly reported measures were Constant score (75%), visual analog scale for pain (VAS-pain; 33%) score, American Shoulder and Elbow Surgeons (ASES) score (21%), Simple Shoulder Test (SST) score (19%), and University of California Los Angeles (UCLA; 17%) shoulder score. An average of 2.5 outcome measures per study were reported. The use of 4 or more outcome scores was associated with publication in higher–impact factor journals. CONCLUSION: Inconsistent reporting of multiple outcome measures is present in the ACJ injury literature. The best scoring system for assessing ACJ injury and treatment has not yet been agreed upon. Until improved scoring systems come into general use, we recommend that future literature on ACJ injuries use at least 4 outcome scores and include the commonly used outcome measures (Constant, VAS-pain, ASES, and SST scores) to enable future comparison of patient outcomes across publications.