[Application of navigation in the fractured spine].

OBJECTIVE

Computer navigation is used in patients with spine fractures to optimize the accuracy of pedicle screws and thereby reduce intra- and postoperative complications, such as injuries to vessels, nerves and accompanying structures. In addition, the ideal screw length and diameter for each pedicle can be detected to ensure optimal stability.

INDICATIONS: Intraoperative navigation is suitable for the treatment of spine fractures, which require dorsal stabilization or fusion. It is primarily used for dorsal procedures ranging from the cervical to lumbar/sacral spine.

CONTRAINDICATIONS: Computer navigation relies on rigid fixation of the dynamic reference base (DRB) at the spinous process. Failure of DRB fixation is the major contraindication for navigation in the spine.

SURGICAL TECHNIQUE: After acquisition of an intraoperative three-dimensional (3D) scan, a digital relation between the anatomy and the 3D scan is established with the navigation system and its infrared camera. Pedicle screws are planned percutaneously with a calibrated pointer. In the next step K‑wires (or screws) are implanted after the pedicles are drilled with a calibrated drill guide. After implantation, an additional 3D scan is performed to verify accurate K‑wire placement.

POSTOPERATIVE MANAGEMENT: Postoperative management does not differ compared to nonnavigated procedures.

RESULTS

Intraoperative navigation in combination with modern imaging systems leads to very high accuracy for pedicle screws. Immediate intraoperative control of K‑wires as well as screws and fracture reduction can avoid revision surgery. Image guidance can reduce radiation exposure for the surgical team.