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

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.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, musculoskeletal tumor society (MSTS) score and visual analogue scale (VAS) were used for evaluation.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).With precise tumor resection and reconstruction with sandwich procedure, the joint-sparing surgery can be performed in selected patients with metastatic periacetabular tumors.