Classification of Galeazzi fracture based on direction of radial displacement. A, Type I, apex volar, fractures are caused by axial loading of forearm in supination, which results in dorsal displacement of radius and volar dislocation of distal ulna. B, Type II, apex dorsal, fractures are caused by axial loading of forearm in pronation, resulting in anterior displacement of radius and dorsal dislocation of distal ulna.