For fixation of small osteochondral fracture fragment which was difficult to fix with ordinary fixation device in comminuted acetabular posterior wall fracture, we employed a modified 3.5mm one thired tubular plate that was shaped into so-called hooked spring plate. During operation, one end of a plate with two to five hole is flattened for a lenght of 1cm. The flattened end is fashioned into two spikes by trimming the end to the adjacent screw holes with a wire cutter. The resultant spikes are bent to 90 with respect to the plate. The residual proteion of the plates is contoured with convex bow with respect to the surface of the bone. The hooks are placed either through the capsule and around the edge of the fragment or they are embedded into the fragment itself. Six consecutive patients undergoing Kocher-Langenbeck approach for open reduction with internal fixation of posterior wall acetabular fracture(7/91-1.93) were reviewed.