Posterior wall acetabular fractures involving a large portion the wall's width and with extensive comminution are difficult fractures to manage operatively. Cortical substitution with a pelvic reconstruction plate and supplemental spring plates has been the traditional means of fixation for these fractures. This option, however, requires the use of multiple, unlinked plates and provides no reliable option for peripheral fixation in comminuted fragments. We describe a novel technique for operative fixation of large, comminuted posterior wall fractures using a single distal tibia pilon plate with the option for peripheral locking screw fixation and report on a series of 20 consecutive patients treated with this method.