3D打印金属假体重建下肢骨干恶性骨肿瘤切除术后骨缺损

The treatment of 3D-printed metal prostheses on bone defect of malignant bone tumors in lower limbs

目的探讨3D打印金属假体重建下肢骨干恶性骨肿瘤切除术后骨缺损的早期疗效。方法回顾性分析2019年3月至2022年3月郑州大学附属肿瘤医院采用3D打印个体化金属假体置换重建34例下肢骨干恶性骨肿瘤切除术后骨缺损的患者资料,男23例、女11例,年龄(19.1±15.2)岁(范围7~80岁),其中22例患者年龄<18岁。病变位于股骨近端3例、股骨中远端15例、胫骨近端10例、胫骨远端6例;骨肉瘤24例、Ewing肉瘤6例、未分化肉瘤2例、骨纤维肉瘤1例、恶性骨巨细胞瘤1例。随访并记录切口愈合情况、有无假体周围断裂及无菌性松动、假体-骨界面愈合情况、双下肢是否不等长、术后并发症等。采用实体瘤疗效评价标准(response evaluation criteria in solid tumor,RECIST)评价肿瘤转归,采用美国肌肉骨骼肿瘤协会(Musculoskeletal Tumor Society,MSTS)93功能评分评价下肢功能。结果所有患者手术均顺利完成,34例患者病变长度(125.5±35.4)mm(范围70~240 mm)、截骨长度(160.2±33.9)mm(范围80~275 mm)。肿瘤均未累及术前设计的截骨面。定制假体均安装牢固,与保留关节面一侧匹配紧密。术后2例出现局部切口脂肪液化、4例出现切口浅表感染,经清创及抗生素治疗后愈合。1例胫骨远端骨肉瘤患者假体-骨界面愈合较差,术后2个月出现严重假体周围感染致假体植入失败,经去除假体、控制感染及使用Ilizarov技术牵拉成骨治疗后感染控制,局部成骨可;其余33例患者假体-骨界面愈合良好。术后7个月,1例患者假体接触面局部骨质有局限吸收,但金属假体及螺钉未松动;其余患者均未发生感染及假体松动、断裂等并发症。术后所有患者均存活且获得随访,随访时间(13.8±5.6)个月(范围7~27个月),无一例发生截骨端肿瘤复发,但5例发生肺转移。16例患者出现双下肢不等长,其中10例长度差<2 cm、3例为2~5 cm、3例超过5 cm。除1例因感染而取出假体外,其余33例患者术后MSTS 93评分为(24.9±2.2)分(范围19~28分),评价为优26例、良7例。根据RECIST标准,34例患者中26例完全缓解、5例疾病进展、3例疾病稳定。结论3D打印金属假体重建是治疗下肢恶性骨肿瘤切除术后骨缺损的有效方式之一,该方法安全可靠,早期疗效满意。

Objective To investigate the early and middle term clinical efficacies of 3D-printed metal prostheses in the reconstruction of bone defects after osteotomy in malignant bone tumors.Methods A total of 34 patients with malignant bone tumors of lower extremity femur and tibia who underwent 3D printing individualized metal prosthesis replacement surgery in the Department of Bone and Soft Tissue of Affiliated Cancer Hospital of Zhengzhou University from March 2019 to March 2022 were retrospectively analyzed.There were 23 males and 11 females,with an average age of 19.1±15.2 years(range,7-80 years).There were 22 children and adolescents younger than 18 years old.There were 3 cases in the proximal femur,15 cases in the middle and distal femur,10 cases in the proximal tibia and 6 cases in the distal tibia.According to the final pathological diagnosis,24 cases of osteosarcoma,6 cases of Ewing's sarcoma,2 cases of undifferentiated sarcoma,1 case of osteosarcoma,and 1 case of malignant giant cell tumor of bone were enrolled in this study.Postoperative complications,wound healing,periprosthetic fracture and aseptic loosening,tumor outcome(evaluated by tumor control evaluation criteria),and length difference of lower limbs were recorded.Response evaluation criteria in solid tumor(RECIST)was used to evaluate tumor outcomes.Prosthetic-bone interface healing was evaluated postoperatively,and the function was evaluated based on Musculoskeletal Oncology Society(MSTS)93.Results The length of lesions was 70-240 mm in 34 patients,with an average of 125.5±35.4 mm.The length of osteotomy was 80-275 mm,with an average of 160.2±33.9 mm.No tumor was found on the osteotomy surface.The customized prosthesis was firmly installed and closely matched with the side of the preserved articular surface.There were 2 patients with local incision fat liquefaction and 4 patients with superficial wound infection,which healed after debridement and antibiotic treatment.One distal tibia osteosarcoma case developed severe periprosthetic infection 2 months after surgery,resulting in prosthesis implantation failure,limb movement pain and poor ankle function.After removal of the prosthesis,infection control and osteogenesis with the Ilizarov technique,the infection was completely controlled and local osteogenesis was possible.The remaining 33 patients had a good prosthetic-bone interface union.One case was found to have localized bone resorption on the contact surface of the prosthesis 7 months after operation,but the metal prosthesis and screws were not loose.The incisions healed well in other patients,without infection,prosthesis loosening,fracture or other complications.All patients survived and were followed up for 13.8±5.6 months(range,7-27 months).During the follow-up,there was no recurrence of tumor at the osteotomy end in all patients,but 5 patients developed lung metastasis.At the end of the last follow-up,all patients survived.Among them,16 patients had unequal length of lower limbs,including 10 cases within 2 cm,3 cases between 2-5 cm,and 3 cases over 5 cm.With the exception of one patient whose prosthesis was removed due to infection,the MSTS 93 of the other patients was 24.9±2.2(range,19-28),and were rated as excellent in 26 cases and good in 7 cases.According to the RECIST evaluation criteria,26 of 34 patients had complete response,5 had disease progression,and 3 had stable disease.Conclusion 3D printed metal prosthesis is one of the effective methods for the treatment of bone defects after resection of malignant bone tumors in lower limbs,which is safe,reliable and has satisfactory early curative effect.