Reconstruction of the spinopelvic stability after total en bloc sacrectomy using a 3D-printed sacral endoprosthesis

English Keywords:Total en bloc sacrectomy  3D printing  Endoprosthesis  Reconstruction of spinopelvic stability

English Abstract:

  【Abstract】 Objectives: To assess the value of 3D-printed sacral endoprosthesis in reconstruction of spinopel-vic stability after total en bloc sacrectomy(TES). Methods: 42 patients who underwent TES in our hospital between January 2015 and December 2018 were retrospectively reviewed. The patients were divided into three groups according to reconstructive option: an endoprosthesis group(14 patients), a combined reconstruction group(19 patients) treated with non-endoprosthetic combined reconstruction including anterior spinal column fixation, and a spinopelvic fixation(SPF) only group(9 patients). Spinopelvic stability(pain and motor function score), implant survival(IS)(failure rate and survival) and surgical safety(operative time, blood loss and perioperative complication rate) in the endoprosthesis group were assessed and compared with those of the other two groups. Results: The mean overall follow-up period was 33.6±14.2 months. In the endoprosthesis group, the mean surgical time and intraoperative hemorrhage was 394.6±128.0min and 3250.0±1711.4ml, respectively. Perioperative complications occurred in two patients. During the final follow-up, 13 patients could walk without aids and 12 patients without using analgesics. Imaging evidence of implant failure was found in 4 patients, including 2 patients who required reoperation. One of these, who had a local recurrence, underwent reoperation without removing the prosthesis due to the solid bone-endoprosthetic osseointegration. And the endoprosthesis of the other patient was removed in reoperation. The mean IS was 49.3(95% confidence interval 40.8-57.9) months. Compared with the other two groups, the endoprosthesis group showed satisfactory spinopelvic stability and IS, which were similar to those of combined reconstruction group(pain score, 2.4±0.8 vs 2.3±0.7, P=0.59; motor function score, 2.4±0.6 vs 2.2±0.7, P=0.44; implant failure rate, 14.3% vs 5.3%, P=0.56; IS, 49.3 vs 59.4 months, P=0.28) and significantly better than those of SPF group(pain score, 2.4±0.8 vs 1.7±1.0, P=0.028; motor function score, 2.4±0.6 vs 1.3±0.7, P=0.001; implant failure rate, 14.3% vs 66.7%, P=0.023; IS, 49.3 vs 28.6 months, P=0.01), with no significantly prolonged operative time, no greater intraoperative haemorrhage or higher perioperative complication rate. Conclusions: The use of 3D-printed endoprosthesis for reconstruction after TES provides reliable spinopelvic stability and IS without endangering the surgical safety.