OBJECTIVE: To propose a new system for classifying proximal humeral neck fractures, and to evaluate intra- and interobserver agreement using the Neer system that is the most commonly used in the area and the Arbeit Gemeinschaft für Osteosynthesefragen system created by an European group, and a new classification system proposed by the authors of this study. METHODS: A total of 56 patients with proximal humeral fractures were selected, and submitted to digitized simple radiography in antero-posterior shoulder and scapular profile. Radiographs were analyzed by three observers at time one, and then three and six weeks later. The kappa coefficient modified by Fleiss was used for the analysis. RESULTS: The mean intra-observer Kappa agreement index (k=0.687) of the new classification, was higher than both the Neer classification (k=0.362) and the Arbeit Gemeinschaft für Osteosynthesefragen (k=0.46). The mean interobserver Kappa agreement index (0.446) of the new classification, also had better results than both the Neer classification (k=0.063) and the Arbeit Gemeinschaft für Osteosynthesefragen (k=0.028). CONCLUSION: the new classification considering bone compression had higher results for intra- and interobserver compared to the Neer system, and the Arbeit Gemeinschaft für Osteosynthesefragen system.
Shoulder fractures; Observer variation
