Histological examination of a retrieved custom-made 3D-printed titanium vertebra: Do the fine details obtained by additive manufacturing really promote osteointegration?

Purpose In the present report it is described the design, the manufacturing and the successful surgical implant of one of the first 3D custom titanium vertebra realized with Additive Manufacturing technique and its use for the spinal reconstruction after en-bloc resection for primary osteogenic sarcoma. Methods Clinical case presentation and the design of the 3D custom titanium vertebra was reported. It was also described the complex procedures adopted to evaluate the retrieved device from the histological point of view, as a tumor relapse hit the patient, one year after the reconstruction procedure. Results The histological evaluation confirmed that the resection technique exerts an important role in promoting bone formation: vertebral body osteotomies favored the reconstruction procedure and maximized the contact area between host bone/vertebral prosthesis thus favoring the bone tissue penetration and device colonization. Conclusion The sharing of these results is very important as they represent the starting point for improving the knowledge starting from the evidence obtained in a challenging clinical condition and with post-operative treatments that could be never reproduced in preclinical model.