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[Intraoperative CT-based spinal navigation: the initial 295 implants experience].

INTRODUCTION
The authors describe the system of spinal navigation based on intraoperative CT imaging and the results of an initial series of patients.


MATERIAL AND METHODS
Spinal screws inserted during 50 surgical procedures in the period between November 2012 and October 2013 were evaluated for insertion accuracy, intraoperative complications and the accessibility of the method for the selected spinal level.


RESULTS
Out of the total of 295 screws inserted throughout all the spinal levels from C0 to S1, only 4 (1.3%) pedicle screws were found to be incorrectly inserted: a single L5 screw breached the lower cortex of the pedicle, two thoracic pedicular screws penetrated the anterior margin of the vertebral body not exceeding 3 mm of the shaft length, and a single C3 pedicle screw penetrated the upper vertebral body end-plate. None of these complications caused morbidity or required re-operation. Intraoperative CT imaging together with the navigation procedure increased the time of surgery by 30 minutes on average and patient radiation exposure during the initial and accuracy control CT scan was increased.


CONCLUSION
Our initial experience has shown that the CT-based computer-assisted spinal navigation system is a precise surgical modality. It enables higher accuracy in spinal screw positioning, resulting in lower surgical morbidity and increased safety for the patient. This benefit should outweigh the longer operation time as well as a higher radiation exposure of the patients.