6533b7cffe1ef96bd12597e2

RESEARCH PRODUCT

Vergleich radiologischer Verfahren zur präoperativen Beurteilung der Verankerungsfestigkeit von Wirbelsäulenimplantaten

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description

PURPOSE To compare three techniques with regards to their ability to estimate pull out strength of spinal fusion hardware. MATERIAL AND METHODS VDS-screw fixation strength in 50 human cadaveric vertebral bodies was approximated by means of pull out force measurement. Bone quality was assessed by Dual X-ray Absorptiometry (DXA). Quantitative Computed Tomography (QCT) and T2*-relaxation time. For each of these techniques, correlation with axial pull out force strength was investigated. RESULTS Highest correlation was found for cancellous bone density measured by QCT (r = 0.72; p < 0.001). Immediately followed by DXA (r = 0.70; p < 0.001), which involves all bone components. Inverted T2*-relaxation time (r = 0.55; p < 0.001) and cortical bone density (QCT) correlated just slightly with pull-out force strength. CONCLUSIONS Absorptiometrical techniques like QCT and DXA are most appropriate to estimate VDS-screw fixation strength preoperatively.