Replacement with 3D-printed custom-made hemipelvic prosthesis for primary malignancy involving the pubis / 中华创伤骨科杂志

ABSTRACT

Objective:To observe the short-term efficacy of 3D-printed custom-made hemipelvic prosthesis in the treatment of primary malignant bone tumors of the pubis.Methods:From June 2017 to May 2019, a total of 5 patients with pubic primary malignant tumor received type Ⅲ hemipelvectomy and reconstruction with a 3D-printed custom-made hemipelvic prosthesis at Department of Orthopedics, West China Hospital. They were 3 males and 2 females with an average age of 36.3 years (range, from 26 to 46 years). Of them, 3 underwent resection of the upper pubic ramus and 2 resection of both pubic rami. All their tumors were chondrosarcomas, with one case of Enneking stage Ⅱa and 4 cases of Enneking stage Ⅱb. Preoperative CT/MRI image fusion was used to determine the tumor-free resection margin, design guide templates for osteotomy and prosthesis, and simulate surgical procedures. A total of 5 3D-printed custom-made hemipelvic prostheses were designed, including 3 ones with an intramedullary stem to preserve partial pubis and 2 ones with a non-intramedullary stem not to preserve the pubis. The functional recovery was assessed by Musculoskeletal Tumor Society (MSTS) scores. The prosthetic position and osseointegration were evaluated by imaging examination. Oncological outcomes and complications were recorded.Results:R0 resection and precise reconstruction were accomplished in all patients. Their intraoperative blood loss ranged from 300 to 3, 700 mL (mean, 1, 680 mL), operation time from 180 to 430 min (mean, 294 min), and follow-up time from 13 to 29 months (mean, 20.6 months). All the 5 patients were alive with no evidence of disease or tumor recurrence. The functional MSTS scores at the final follow-up ranged from 29 to 31 (mean, 29.8). One male patient complained of erectile dysfunction. Fretting wear around the prosthetic stem was found in 3 patients while bone wear on the normal pubic side in 2. Osseointegration was observed in all patients with no complications like deep infection, prosthesis dislocation, prosthetic or screw breakage.Conclusion:Since 3D-printed custom-made hemipelvic prostheses can result in fine short-term efficacy for pubic primary malignant bone tumors, they may be a reliable method to reconstruct pelvic malignant tumors.