mason classification of radial head fractures
Type Description
I Fissure or marginal sector fractures with <2mm displacement
II Marginal sector fractures including <30% of the radial head with >2mm displacement
III All have comminutions involving the entire head of the radius, subtyped as
III A Fracture of the entire radial neck, with the head completely displaced from the shaft
III B Articular fracture involving the entire head, consisting of more than two large fragments
III C Fracture with a tilted and impacted articular segment
IV Comminuted fracture with elbow dislocation
