Trans-sacral fixation for failed posterior fixation of the pelvic ring.

Introduction: In the treatment of certain pelvic ring pathologies (non-unions and failure of ilio-sacral screw fixation) trans-sacral fixation (i.e. fixation from iliac wing to the other traversing the body of S1) may be necessary. The purpose of our study was to describe our early experience and describe the surgical technique.

Materials And Methods: Seven cases of trans-sacral fixation were identified with a mean patient age of 49-years-old with four females and three males. The diagnosis at the time of trans-sacral fixation was failure of posterior ring fixation in four (three of which had vertical sacral fractures), mal-position of iliosacral (IS) screw in one, failure of fusion of sacroiliac (SI) joint in two. All these cases were augmented with a 4.5 mm reconstruction plate placed in tension posteriorly.

Results: At average follow up of 39 months (range 24-75), all patients achieved union. There were no neurological or vascular complications. Two patients required reoperations prior to union. Our current use for this technique is with a 8.0 mm screw (16 mm thread).

Conclusions: Initial experience with trans-sacral fixation has proven to be very effective technique to solve the most difficult problems in posterior pelvic ring fixation. We reserve its use to the following indications: nonunion/malunion of the pelvic ring, and sacral fractures.