The accuracy of 3D fluoroscopy-navigated screw insertion in the upper and subaxial cervical spine.
OBJECTIVE
Due to better primary stability and repositioning options, pedicle screws are increasingly used during posterior stabilization of the cervical spine. However, the serious risks generally associated with the insertion of screws in the cervical spine remain. The purpose of this study is to examine the accuracy of pedicle screw insertion with the use of 3D fluoroscopy navigation systems, also accounting for various spine levels.


METHODS
Data of 64 patients were collected during and after screw implantation (axial and subaxial) in the cervical spine. 207 screws were implanted from C1 to C7 and analyzed for placement accuracy according to postoperative CT scans and following the modified Gertzbein and Robbins classification.


RESULTS
The accuracy of most of the inserted screws was assessed as grade 2 according to the modified Gertzbein and Robbins classification. 93.9% of the screws implanted at C1 or C2, and 78.51% of the screws implanted at levels C3-C7 showed placement accuracy grade 2 or better, indicating pedicle wall perforation of <2 mm. Overall, seven complications were observed. In three cases, the vertebral artery was affected, leading to one fatality. Surgical revision was necessary once because of Magerl screw misplacement and three times due to impaired wound healing. No radicular symptoms resulted from screw malposition.


CONCLUSIONS
Axial and subaxial screws can be inserted with a high grade of accuracy using 3D fluoroscopy-based navigation systems. Nevertheless, while this useful innovation helps to minimize the risks of misplacement, the surgery is still a challenge, as arising complications remain severe.
Department of Orthopedic and Trauma Surgery, University Hospital of Cologne, Kerpener Strasse 62, 50937, Cologne, Germany. jan.bredow@uk-koeln.de.
J
J
Bredow
Department of Orthopedic and Trauma Surgery, University Hospital of Cologne, Kerpener Strasse 62, 50937, Cologne, Germany.
J
J
Oppermann
Department of Radiology, University Hospital of Cologne, Cologne, Germany.
B
B
Kraus
Institute of Medical Statistics, Informatics and Epidemiology, University Hospital of Cologne, Cologne, Germany.
P
P
Schiller
Department of Trauma, Orthopedic and Hand Surgery, Vinzenz-Pallotti Hospital, Bergisch Gladbach, Germany.
G
G
Schiffer
Department of Orthopedics, Medical Center City Aachen GmBH, Wuerselen, Germany.
R
R
Sobottke
Department of Orthopedic and Trauma Surgery, University Hospital of Cologne, Kerpener Strasse 62, 50937, Cologne, Germany.
P
P
Eysel
Department of Spine Surgery, KLINIK am RING, Cologne, Germany.
T
T
Koy
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001863:Bone Screws; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery*; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D025321:Surgery, Computer-Assisted; D055815:Young Adult
Accuracy of screw insertion; Cervical spine; Complications in cervical spine surgery; Navigated screw insertion; Spine surgery