Table 1.

Mean ± SD of micro-CT, gravimetric, and CAD volumes of the tibial inserts

Insert type	Micro-CT volume (mm3)	Gravimetric volume (mm3)	CAD volume (mm3)	Scaling factor
CR	27,644 ± 64 (0.64%)	27,738 ± 52 (0.3%)	27,822	0.99786
PS	31,951 ± 139 (0.11%)	32,036 ± 56 (0.2%)	31,985	0.99964

The mean percent difference from the CAD volume is listed for the micro-CT and gravimetric volumes. Scaling factor refers to the linear scaling factor isotropically applied to reduce the CAD geometry to equal the mean volume of the scanned geometries. No SD exists for the CAD volumes, because there was only one CAD file; CAD = computer-aided design; CR = cruciate-retaining; PS = posterior-stabilized.