Transiliac Internal Fixator

Abstract

The transiliac internal fixator is a posterior bridging stabilization device and an alternative to posterior bridging plate osteosynthesis and transsacral bar fixation. The principle of this technique is to insert one pedicle screw in each ilium and connect them with a transverse rod. The pedicle screws can be inserted in the cranio-caudal or in the posterior-anterior direction. In the first version, pedicle screws are inserted in the posterior ilium 1–2 cm cranial to the superior posterior iliac spine parallel to the posterior gluteal line in a cranio-caudal direction. In the second version, the screws are inserted from the superior posterior iliac spine and directed towards the anterior inferior iliac spine. Coverage of the implants by the fascia is an important factor to avoid soft tissue problems. The internal fixator provides angular stable fixation of the broken hemipelvis to the intact one. It is suitable for the treatment of simple unilateral osteoporotic sacral fractures in the central, transforaminal or alar region of the sacrum. The biomechanical performance was tested in a single leg stance model and showed no significant differences with three competitive options for treatment. In a prospective study including 31 patients, none of the 62 pedicle screws inserted into the ilium in a cranio-caudal direction was positioned incorrectly. There were no neuro-vascular lesions, one case of loosening of a pedicle screw and two superficial wound infections. The clinical follow-up showed a sufficient mechanical stability of the fixations in all patients despite immediate weight-bearing as tolerated. No loss of reduction or secondary dislocation occurred. Transiliac internal fixation is a technically easy, less invasive and safe method for the fixation of unilateral fragility fractures of the sacrum.