NAVIGATED REDUCTION AND FIXATION OF ACETABULAR FRACTURES

Abstract

Acetabular and pelvic fractures are amongst the most challenging to treat, still requiring major open surgery. The operations to reduce and fix them entail lengthy operative time, significant blood loss and use of ionising radiation.

We report on the initial stages of developement of a minimally invasive method for navigated reduction and percutaneous fixation of acetabular fractures (NRFA). A commercial navigation platform (Acrobot Ltd.) will be adapted for use with this technique. CT based planning will be used to identify the correct realignment of the the bone fragments, which will then be reduced percutaneously with the aid of two tracked arms attached to the navigation system. Schanz pins, which are inserted in pre-operatively planned sites in each fragment using safe trajectories, are handled as joysticks to manipulate the fracture under computer assistance. Registration of the fragments after insertion of the joysticks will be carried out by means of fluoroscopic images of the AP and Judet views of the fractured acetabulum. Once reduction is achieved by following on-screen instructions, the joysticks are held in place by a custom clamping system connected to one of the arms, while the other is used for percutaneous insertion of column screws.

This technique is potentially suitable for a number of acetabular fractures which include transverse, anterior column, posterior column, T-fractures and some associated both columns fractures. These constitute over 50% of Letournel’s and 60% of Matta’s original series of acetabular fractures. Furthermore, this percutaneous technique could reduce bleeding, wound complications, hospital stay and cost of treatment. Intra operative ionising radiation would be greatly reduced for both patients and the surgeons.

Adequate training with the use of this software may provide a greater number of surgeons the capability to surgically treat these complex fractures.