Fracture mapping of displaced partial articular fractures of the radial head

Recognition of patterns of traumatic elbow instability helps anticipate specific fracture characteristics and associated injuries. The objective of this study was to assess the association of fracture line distribution and location of displaced partial articular radial head fractures with specific patterns of traumatic elbow instability using fracture mapping techniques.

Fracture line distribution and location of 66 acute displaced partial articular radial head fractures were identified using quantitative 3-dimensional computed tomography reconstructions that allowed reduction of fracture fragments and a standardized method to divide the radial head into quadrants with forearm in neutral position. Based on qualitative and quantitative assessment of fracture maps, the association between fracture characteristics of displaced partial articular radial head fractures and specific elbow fracture patterns was determined.

In partial articular radial head fractures, the highest fracture line intensity was located in the anterolateral quadrant near the center of the radial head. Fracture location corresponded with fracture line distribution; most fractures involved the anterolateral quadrant (n = 65; 98%), whereas parts of the posteromedial quadrant were involved in a minority of the fractures (n = 10; 15%). The association of fracture line distribution and location with overall fracture patterns of the elbow, as depicted on fracture maps, was not statistically significant.

Fracture maps demonstrated no association between fracture line distribution and location of displaced partial articular fractures of the radial head and overall specific patterns of traumatic elbow instability, suggesting a common fracture mechanism that involves the anterolateral part of the radial head in most patients.