Precise joint preserving surgery by using Three-Dimensional Printing Technology for metastatic periacetabular bone tumor: A technique note and preliminary report

Background/purpose: Complex arthroplasties for periacetabular metastatic lesions can result in complications including infection and prosthesis loosening owing to poor bone quality. A new surgical protocol has been developed as a joint-sparing surgery to avoid complications after arthroplasties. The main surgical steps are: (a) conservative and accurate tumor resection with aid of 3D printing model-assisted preoperative resection simulation and preparation of pre-contour plate, (b) reconstruction with structural bone graft through the sandwich technique for augmentation of subchondral bone.Methods: This retrospective study consisted of 6 patients (5 with metastatic bone tumors and one with multiple myeloma). The pelvic bone resection as defined by Enneking and Dunham were typed I + II in 2 patients and type II in 4 patients. The medical records, images, muscu-loskeletal tumor society (MSTS) score and visual analogue scale (VAS) were used for evaluation. Results: The mean operative time was 234 minutes, and the average surgical blood loss was 1408 mL. The mean follow-up period was 21 months. The mean VAS significantly decreased at postoperative 1-week and 1-year follow-up. There were no intraoperative or early postoperative complications. The median MSTS score during the final follow-up was 26 points (range, 14-28 points). Except for one case who experienced severe joint destruction, all the other five cases were classified as excellent or good (>15).Conclusion: With precise tumor resection and reconstruction with sandwich procedure, the joint-sparing surgery can be performed in selected patients with metastatic periacetabular tu-mors.Copyright 2022, Formosan Medical Association. Published by Elsevier Taiwan LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).