External fixation of pelvic fracture ex vivo

Cranial dislocations of the fractured hemipelvis is the most difficult component to reduce and control by external fixation. The stabilizing effect of several external frames was studied using a cadaver pelvis. Single frames, double frames, trapezoid frames and double trapezoid frames were mounted in three pin units on each anterior iliac crest. Successively increasing the number of transverse connecting rods increased the stability of the construction. Wiring of the symphysis had the same effect, when constructions with one or two transverse rods were used. Double fixation sites of the pin units in the anterior pelvis added only marginally to the stability. The highest rigidity was achieved using a circumferential frame with pin units in both anterior and posterior iliac crests.