Purpose of the study: Pelvic fractures disrupting the pelvic girdle often create a serious challenge for reduction and fixation. Type C fractures of the Tile classification provoke vertical instability. Percutaneous screw fixation under fluoroscopic control in patients positioned in dorsal decubitus enables an extension of early indications for fixation to patients with abdominal or thoracic injuries. The reduction is obtained by progressive transcondylar traction on an orthopedic table. The purpose of this study was to assess functional mid-term outcome and to analyze causes of failure.

Material and methods: From 1995 through 2003, we used the percutaneous sacroiliac screw fixation method for type C fractures in 25 patients; clinical assessment at 45 months mean follow-up was available for 22 patients. Six patients presented a bilateral lesion (C2), seven a vertical sacral fracture (C1-3), and nine sacroiliac disjunction (C1-2). One screw was inserted for ten patients, two screws for twelve. Complementary anterior osteosynthesis was performed for eight patients.

Results: The functional outcome was assessed with the Mageed score. The mean score was 801%. All patients presente satisfactory postoperative reduction (less than 10 mm residual vertical displacement). Early displacement was noted one day 10 in one patient who underwent a revision procedure. There were two late secondary displacements (one with mobilization and one with material fracture) which heal in a misaligned position. There were no iatrogenic complications (neurologic, vascular, infectious) and no cases of nonunion.

Discussion: The long-term functional results were directly related to the quality of the reduction, as previously demonstrated by Matta. In our series, the quality of the postoperative reduction was significantly correlated with time from trauma to surgery. This delay must be as short as possible (less than five days for Routt). The main complication was secondary displacement which was observed in this study among cases with a single posterior screw.

Conclusion: Percutaneous sacroiliac screw fixation provides good functional results and appears to be a safe technique if the initial reduction is satisfactory. Two posterior screws are needed to avoid secondary displacement.