Evaluation of the Efficacy of 3D-Printed Hemipelvic Prosthesis Replacement Surgery in the Treatment of Enneking Stage Ⅱ+Ⅲ Malignant Pelvic Tumors

Zhang Qiang; Du Junwei; Wu Junshen; Jiang Renbing

Abstract：Objective To assess the therapeutic efficacy of 3D-printed hemipelvic endoprosthesis replacement in managing Enneking stage Ⅱ+Ⅲ pelvic malignant tumors and evaluate the safety and functional outcomes associated with preserving the anterior inferior iliac spine during the surgical procedure.Methods This retrospective study encompassed a cohort of 25 patients diagnosed with Enneking stage Ⅱ+Ⅲ pelvic malignant tumors who underwent 3D-printed hemipelvic endoprosthetic replacement surgery at our institution from January 2018 to January 2020.The patient demographics included 11 males and 14 females,with ages ranging from 17 to 77 years,yielding a mean age of(49.96±9.73)years.The tumor histologies comprised 11 cases of conventional osteosarcoma,6 of chondrosarcoma,3 of telangiectatic osteosarcoma,3 of Ewing's sarcoma,1 case of metastatic paraganglioma originating from the lumbar spine,and 1 case of metastatic renal clear cell carcinoma.Based on the surgical approach adopted,patients were categorized into two groups:a study group(10 patients)where the anterior inferior iliac spine was preserved during surgery,and a control group(15 patients)where it was not retained.Intraoperative metrics,such as surgical duration and blood loss,were recorded for both groups.Prosthetic acetabular rotation center displacement was evaluated using imaging techniques.Postoperative assessments were performed utilizing the musculoskeletal tumor society(MSTS)score,Harris hip function score,and hospital for special surgery(HSS)knee function score.Furthermore,oncological outcomes,including recurrence rates and survival data,were analyzed.Complications encountered during and after surgery were also documented and analyzed.Results The follow-up period for all patients ranged from 16 to 27 months,averaging at(21.92±3.40)months.Analysis revealed no statistically significant differences in surgical duration or intraoperative blood loss between the study group(with preserved anterior inferior iliac spine)and the control group(without preservation)(P＞0.05).However,at both postoperative and final follow-up assessments,the study group demonstrated significantly higher MSTS functional scores,Harris hip scores,and HSS knee scores compared to the control group,with statistically significant differences observed(P＜0.05).Notably,the comparison of acetabular prosthetic rotation center offset between the two groups at the last follow-up did not yield statistically significant differences(P＞0.05).Postoperative complications included 3 cases of surgical site infections and 2 instances of fat liquefaction necrosis around the incision site,all of which resolved with appropriate treatment.During the last follow-up,one patient with pelvic metastatic tumor was diagnosed with liver metastasis one year after surgery.This patient was managed with targeted therapy and remained alive with the tumor under control.No instances of tumor recurrence or metastasis were observed in the remaining patients.Conclusion Our study concludes that 3D-printed hemipelvic prosthesis surgery represents a safe and effective therapeutic approach for managing Enneking stage Ⅱ+Ⅲ pelvic malignant tumors.Furthermore,the preservation of the anterior inferior iliac spine and associated muscle attachment points during surgery is pivotal in facilitating optimal functional recovery of the hip and knee joints,as evidenced by the superior functional outcomes observed in the study group.This surgical technique offers a promising option for improving both oncological outcomes and quality of life for patients with complex pelvic malignancies.