3D Computer tomography for measurement of femoral position in acl reconstruction

Abstract

Objective: To validate intra- and inter-class correlation coefficients of a transparent 3D-TC protocol and investigate relationships between different axial rotations. Methods: Twenty unilateral knee TCs (iSite - Philips) were evaluated by means of a transparent 3D-TC OsiriX Imaging Software (v.3.9.4), 3D MPR protocol. Mathematical model of femoral tunnel projections acquired on vertical and horizontal rotations from -20 to +20 degrees. Height (h'/H) and length (t'/T) of tunnel projections have been analyzed by the Bernard and Hertel's method. Statistics: power of study=80%, ICC, ANOVA, p>0.05 (SPSS-19). Results: Transparent 3D-TC showed high reliability of both intra-observer (h'/H=0.941; t'/T=0.928, p>0.001) and inter-observer (h'/H=0.921; t'/T=0.890, p>0.001) ICC. ACL Length (t'/T) and Height (h'/H) projections were statistically different on vertical and horizontal rotations: p=0.01 and p>0.001, respectively. Conclusion: This new transparent 3DTC protocol is an accurate and reproducible method that can be applied for ACL femoral tunnel or footprint measurement with high ICC reliability.