The optimal, final construct involves fragment specific fixation as well as plate stabilization of the posterior wall.
Fragment specific fixation will depend on the size and location of the fragments. Ideally, lag screw fixation of each fragment should occur as demonstrated in this illustration.
Screw size is determined by the fragment size, and can be 1.5 mm, 2.0 mm, 2.7 mm or 3.5 mm.
The superior posterior wall fracture fragments are commonly quite large and allow screw fixation into the sciatic buttress for excellent purchase. It is, however, common to encounter multifragmentary posterior wall fractures requiring smaller fragment fixation.
The final construct may require more than one plate (see below). Therefore, lag screw placement should be strategic so as not to block plate placement.
At times, 2.0 mm screws may be utilized to secure small peripheral posterior wall fragments. The definitive plate(s) may lie directly over these low-profile screws.