Classification of proximal humerus fractures according to pattern recognition is associated with high intraobserver and interobserver agreement.

Background: The Mayo-Fundación Jiménez Díaz (FJD) classification for proximal humerus fractures aims to identify specific fracture patterns and apply displacement criteria to each pattern. The classification includes 7 common fracture patterns: isolated fractures of the greater or lesser tuberosity, fractures of the surgical neck, impacted fractures involving head rotation in a varus and posteromedial direction or in valgus, and fractures where the humeral head is dislocated (head dislocation), split (head splitting), or depressed (head impaction). The purpose of this study was to evaluate the intraobserver and interobserver agreement of the Mayo-FJD classification system using plain radiographs (xR) and computed tomography (CT).