Lateral compression fracture of the pelvis represents a heterogeneous group of complex 3D patterns of displacement

Although clinical and radiological criteria exist to direct the non-operative and operative treatment of other types of pelvic injuries, none exist for lateral compression (LC) fractures. The purpose of this study is to describe the patterns of injury in LC fractures through quantitative 3D radiographic analysis. It is hypothesised that LC fractures represent a spectrum of injuries with a combination of translational and rotational displacements. CT data from 60 patients with unilateral lateral compression fractures were obtained. Quantification of translations and rotations of the fractures was performed using 3D visualisation software. Fractures initially diagnosed as LC actually represent a spectrum of displacement patterns, ranging from a minimally displaced hemipelvis to complex combinations of displacements. Fractures were grouped based on pattern of rotation and translation into 5 distinct groups. 3D analysis of displacement patterns demonstrated a complexity in LC fractures which may explain the variations seen in outcomes associated with this injury.