Accuracy of external measurements of 3-dimensional (3D) printed biomodels of the canine radius used in an in-hospital setting.

The objective of this study was to determine if biomodels printed on a fused deposition modeling (FDM) device from computed tomography (CT) data are accurate by comparing external measurements to the native bone, considering that the clinical usefulness of the printed biomodels in an in-hospital setting depends on their verified accuracy and consistency. Using canine cadaveric radii previously stripped of all soft tissues, 7 parameters of the actual bone and the 3-dimensional (3D) printed biomodels were measured and compared to determine how accurately the models represent the cadaveric bone. A total of 28 canine radii were collected, in which the landmarks for measurements were established. Radiographs were then taken to determine the frontal center of rotation of angulation (CORA) and CT scans were carried out. Finally, a 3D virtual reconstruction was done and converted into a stereolithography (STL) format file, from which 2 biomodels were printed per bone. Measurements for biomodels were compared for equivalence to cadaveric measurements. For the 7 measured parameters, the mean difference between biomodel and cadaveric parameters ranged from an increase of +0.66% in cranial-caudal proximal (CrCdP)-CORA to a decrease of -1.32% in distal width of the radius. For all 7 measured parameters, measurements for biomodels were statistically equivalent to their corresponding cadaveric bone (P < 0.001). The 7 measured parameters in the 3D models printed with an FDM device were not significantly different than those in the original bone. In fact, these measurements closely approximated original bone measurements (within 1.5%); therefore, validating their application in future presurgical planning for various orthopedic procedures.