We applied internal fixation using a spring plate against an acetabular posterior wall fracture including small fragments and then evaluated the clinical and radiological results and want to understand the usefulness of the spring plate.

Fifteen patients in whom fixation was difficult using leg screws or a metal plate because of a small bone fragment, in patients with posterior wall acetabular fractures who presented in our hospital since August of 2011 to March of 2014 were enrolled. The mean age was 42.6 years (range 24-54 years) with relatively young patients, and they were followed-up for at least one year. We analyzed the rate of reduction after surgery using the classification of Matta in radiographs, and the classification of Borrelli in 3-dimensional computed tomography (CT) and clinical results were evaluated using the clinical grading system.

There were five cases of anatomical reduction, 9 cases of imperfect reduction, and 1 case of unsatisfactory reduction according to the classification of Matta. Except for one case during the follow-up period, the union of bone was successful without failure of fixation and the clinical results were 6 cases of excellence, 8 cases of good, and 1 case of failure. Articular displacement was also evaluated in postoperative CT scan according to Borrelli's criteria. The mean of gap and step off was 2.04 mm, 1.3 mm.

Use of leg screw fixation and so on in posterior wall fractures including a small fragment of the acetabular rim is not easy. However the method using spring plate fixation enables relatively accurate reduction and fixation for a small fragment and the clinical outcome showed satisfactory results.