Perlepe V, et al. - A total of 29 CT examinations of tibial or femoral non-unions to get 87 stacks of 7 CT reformats each in the coronal (n = 29), sagittal (n = 29) or transverse (n = 29) planes were used by the researchers in order to evaluate how many and which CT reformats of long bone non-unions should be investigated to best approximate the interpretation of a greater number of CT reformats obtained in the three orthogonal planes. For both observers, three models combining two (mid-coronal and mid-sagittal), three (mid-coronal, mid-sagittal and mid-transverse) or four (two paramedian coronal and sagittal) CT reformats had the greatest intra-class correlation coefficient. Following resampling, the two other models were statistically outperformed by the model combining the two paramedian sagittal and coronal CT reformats. Thus, of the two paramedian sagittal and coronal CT reformats, the semi-quantitative analysis was concluded as an agreeable option for the investigation of more numerous reformats.