3D printed hemipelvic prosthesis for treatment of pelvic malignant tumors resected via sacroiliac joint / 中华骨科杂志

ABSTRACT

Objective:To analyze the surgical techniques, surgical indications and early clinical effects of 3D printed hemipelvic prostheses in the reconstruction of pelvic malignant tumors resected by the sacroiliac joint.Methods:From January 2016 to March 2020, a retrospective analysis of 9 patients with malignant tumors involving pelvis I+II or I+II+III region were treated with sacroiliac joint osteotomy and 3D printed pelvic prosthesis reconstruction. There were 7 males and 2 females; their age was 51.1±10.5 years (range 27-66 years). Among them, 5 cases were chondrosarcoma, 1 case was pleomorphic undifferentiated sarcoma, 2 cases were metastatic renal cell carcinoma, and 1 case was metastatic primitive neuroectodermal tumor. Resection of pelvic area I+II or I+II+III were according to the extent of tumor involvement. During the resection of pelvic I region, osteotomy was done through sacroiliac joint surface, and 3D printed hemipelvic prosthesis that fits the sacral auricular surface was used for reconstruction. Postoperative imaging examination was used to evaluate the acetabular rotation center deviation of the pelvic prosthesis; the International Bone Tumor Society (Musculoskeletal Tumor Society, MSTS) function score was used for functional evaluation; the patient's oncology outcome and postoperative complications were evaluated.Results:All 9 patients successfully completed the operation. The operation time was 3.5-6 hours, with an average of 4.5 hours. The intraoperative blood loss was 800-3 000 ml, with an average of 1 400 ml. 3 patients underwent resection and reconstruction of pelvis I+II area, 4 patients underwent pelvic resection and reconstruction of I+II+III area, 2 patients underwent pelvic I+II+III area combined with proximal femur resection and reconstruction; all patients were followed up. The follow-up time was 6-50 months, with an average of 16 months. At the last follow-up of 9 patients, the MSTS score was 12-26, with an average of 20.2; the postoperative rotation center horizontal displacement distance was 10.67±7.12 mm, and the vertical displacement was 8.56±4.22 mm. One case of metastatic cancer was found to have multiple metastases throughout the body during chemotherapy 3 months after surgery, and died in 7 months after surgery; 1 case of pelvic metastatic renal cell carcinoma developed multiple metastases within one and a half years after surgery, controlled by targeted drugs, and survived with the tumor; the rest seven cases had no recurrence at the surgical site and no distant metastasis was found.Conclusion:The semipelvic prosthesis with 3D printed auricular surface has potential advantages in reconstructing the bone defect of the pelvis I+II or I+II+III area after the sacroiliac joint osteotomy. The short-term efficacy is relatively satisfactory, and the long-term efficacy remains to be further observed.