Isolated posterior column fractures are rare and are usually associated with a posterior dislocation of the hip.
Posterior column fractures originate at the greater sciatic notch, pass through the roof or weight bearing dome and exit through the obturator ring. The result is a complete detachment of the posterior column.
The fracture is usually displaced posteriorly, medially, and in internal rotation, as the posterior column rotates about the ischial tuberosity.
Further details on posterior column fractures are provided in section Characteristics of elemental fracture types.
A summary of diagnosing the fracture classification based on x-ray and CT images is presented in section Patient assessment.
The section Radiology of the intact acetabulum provides explanation of the radiologic landmarks.
The section Characteristics of elemental fracture types provides further information on the radiology of posterior column fractures.
X-ray image of posterior column fracture, courtesy of C Sancineto