[Precision of navigation-assisted surgery of the thoracic and lumbar spine].
The goal of these studies was to evaluate the accuracy of in vivo and in vitro application of CT- and C-arm-based navigation at the thoracic and lumbar spine. With CT based navigation, 82 pedicle screws were consecutively inserted, 53 into the thoracic and 29 into the lumbar spine. Seven (13%) perforations were detected at the thoracic spine and two (7%) at the lumbar spine. Additionally, minor perforations below the thread depth were seen in six (11%) thoracic and in two (7%) lumbar instrumentation. With C-arm-based navigation, 74 screws were consecutively placed into 38 thoracic and 36 lumbar pedicles. Perforations were noted in ten (26%) thoracic and four (11%) lumbar implants. Minor perforations were observed in another nine (24%) thoracic and ten (28%) lumbar pedicles. The observer-independent and standardized in vitro study based on a transpedicular 3.2-mm drill hole aiming a 4-mm steel ball in a plastic bone model showed pedicle perforations of the drill canal only in thoracic vertebrae, 1 of 15 in CT-based and 3 of 15 in C-arm navigation. The quantitative calculation of the smallest distance between the central line through the drill canal and the center of the steel ball resulted in 1.4 mm (0.5-4.8 mm) for the CT-based navigation at the thoracic spine and in 1.8 mm (0.5-3 mm) at the lumbar spine. For the C-arm based navigation the distance was 2.6 mm (0.9-4.8 mm) for the thoracic spine and 2 mm (1.2-3 mm) for the lumbar spine. In our opinion, the clinical results of the comparative accuracy of CT- and C-arm-based navigation in the present study showed moderate advantages of the CT-based technique in the thoracic spine, whereas CT- and C-arm based navigation had comparable perforation rates at the lumbar pedicle. The results of the experimental study correlated with the clinical data.
Arand
M
M
Abteilung für Unfallchirurgie, Hand- und Wiederherstellungschirurgie, Universität, Ulm. markus.arand@medizin.uni-ulm.de
Schempf
M
M
Hebold
D
D
Teller
S
S
Kinzl
L
L
Gebhard
F
F
D001860:Bone Plates / Q000706:statistics & numerical data; D001863:Bone Screws / Q000706:statistics & numerical data; D004869:Equipment Safety / Q000706:statistics & numerical data; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D008432:Mathematical Computing; D008953:Models, Anatomic; D011183:Postoperative Complications / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*; D013673:Technology Assessment, Biomedical / Q000706:statistics & numerical data*; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D036542:Tomography, Spiral Computed / Q000295:instrumentation*