[Pullout resistance of conventional pedicle screw implantation in comparison to fluoroscopic computer-assisted technique].
OBJECTIVE
Aim of the study was to compare pullout resistance of pedicle screws after conventional and fluoroscopic computer-assisted implantation in the cadaveric thoracic and lumbar spine.


METHODS
Pedicle screws were inserted in a total of 10 vertebrae of different human specimens: 10 screws were placed using conventional technique (group 1) and 10 screws were inserted with fluoroscopic computer-assisted system contralaterally (group 2). Then pedicle screws were evaluated for biomechanical axial pullout resistance.


RESULTS
Mean pullout force was 232 N (range 60-600 N) in group 1 and 353 N (range 112-625 N) in group 2. The difference was significant (p=0,0425).


CONCLUSIONS
Fluoroscopic navigated implantation of pedicle screws increases the pullout strength in thoracic and lumbar cadaveric spines as compared with conventional methods.
Linhardt
O
O
Orthopädische Klinik der Universität Regensburg, Bad Abbach. o.linhardt@asklepios.de
Perlick
L
L
Renkawitz
T
T
Matussek
J
J
Plitz
W
W
Grifka
J
J
D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D001864:Bone Wires; D002102:Cadaver; D003627:Data Interpretation, Statistical; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D008159:Lumbar Vertebrae / Q000601:surgery; D008297:Male; D008875:Middle Aged; D013131:Spine / Q000601:surgery*; D025321:Surgery, Computer-Assisted; D013904:Thoracic Vertebrae / Q000601:surgery