Compassionate use of a custom 3D-printed sacral implant for revision of failing sacrectomy: case report.

Reconstruction of the spinopelvic continuity after sacral resection for primary sacral tumors remains challenging. Complex anatomical and biomechanical factors of this transition zone may be addressed with the advancement of 3D-printed implants. Here, the authors report on a 67-year-old patient with a sacral chordoma who initially underwent total en bloc sacrectomy followed by standard spinopelvic reconstruction. Pseudarthrosis and instrumentation failure of the lumbosacral junction construct subsequently developed. A custom 3D-printed sacral prosthesis was created using high-resolution CT images. Emergency Food and Drug Administration approval was obtained, and the custom device was implanted as a salvage reconstruction surgery. Made of porous titanium mesh, the custom artificial sacrum was placed in the defect based on the anticipated osteotomic planes and was fixed with a screw-rod system along with a fibular bone strut graft. At the 18-month follow-up, the patient was disease free and walking short distances with assistance. CT revealed excellent bony incorporation into the graft.The use of a custom 3D-printed prosthesis in spinal reconstruction has been rarely reported, and its application in sacral reconstruction and long-term outcome are novel. While the implant was believed to be critical in endowing the region with enough biomechanical stability to promote healing, the procedure was difficult and several key learning points were discovered along the way.