External fixation of fractures and fracture dislocations of the pelvis

External fixation of pelvic fracture dislocations is appropriate when reduction must be accomplished by noninvasive methods which are nonetheless capable of precise regulation. The corrective frames described can be applied with minimal trauma and are capable of orientating the necessary corrective forces in the required directions to reduce the wide variety of bony displacements and dislocations encountered in these injuries. The apparatus is flexible and the choice of particular technique and assemblies is determined by evaluating the biomechanics of the mechanism of injury and applying the appropriate antagonist forces. These forces operate in three fundamental planes: anteroposterior, lateral and vertical. The author describes and illustrates how the assembly may be used to operate in these planes and reduce and stabilise a variety of displacements encountered in fractures and fracture dislocations of the pelvis.