3D打印金属支撑假体联合关节面自体骨植骨治疗股骨远端CampanicciⅠ、Ⅱ级骨巨细胞瘤的早期随访研究

Early clinical outcomes of three-dimensional printed metal-supported prosthesis combined with articular surface autogenous bone graft for campanicci gradeⅠorⅡgiant cell tumor of the distal femur

目的报道一种具有良好生物相容性和骨整合能力的3D打印金属支撑假体及9例临床应用结果。方法2018年6月至2021年1月,9例股骨远端CampanacciⅠ级或Ⅱ级骨巨细胞瘤(giant cell tumor of bone,GCTB)患者进行了扩大病灶内刮除术,然后采用3D打印金属支撑假体结合关节面下自体骨植骨重建。术前对膝关节疼痛、功能和软骨下骨的完整性进行评估作为基线资料,根据每例患者的三维CT数据为其定制假体。术后对所有患者定期随访膝关节术后疼痛、膝关节功能、软骨下骨层的厚度、宿主骨与自体植骨愈合情况、自体植骨及宿主骨在假体表面骨长入情况,以评估临床和影像学预后。结果患者术后随访18~42个月,平均(30.8±7.5)个月。术前受影响的软骨下骨比例和软骨下骨厚度分别为(31.8±9.6)%(18.2%~50.2%)和(2.2±0.8)mm(1.2~4.0 mm)。末次随访时,膝关节视觉模拟评分(visual analogue scale,VAS)低于术前[0 vs.(4.8±2.2)分];美国骨肿瘤协会(Musculoskeletal Tumor Society,MSTS)评分显著高于术前[(26.7±2.4)vs.(18.8±3.7)分];膝关节屈曲范围较术前改善[(122.8±9.1)°vs.(108.3±6.1)°]。此外,末次随访时,患者平均软骨下骨厚度增加到(10.9±1.3)mm(9.1~12.1 mm)。末次随访时,患者活动范围(range of motion,ROM)、VAS评分、MSTS评分、软骨下骨层厚度与术前比较差异均有统计学意义(P<0.001)。所有患者软骨下植骨与宿主骨愈合,假体表面骨长入良好。无肿瘤局部复发或肺部远处转移;无术后并发症发生。结论3D打印金属支撑假体重建较传统的骨水泥重建具有独特的优势,如良好的生物相容性、骨整合能力和软骨下骨保护,采用3D打印金属支撑假体联合关节面下自体骨植骨治疗股骨远端CampanacciⅠ级或Ⅱ级GCTB患者的早期临床疗效满意。

Objective Giant cell tumor of bone(GCTB)is a primary junctional tumor of the long bones around the knee with localized invasive properties,and it tends to invade the subchondral bone area in the distal femur.The current reconstructive approach for its cavity bone defects is mainly bone cement filling combined with subarticular surface autogenous bone grafting,but the main drawback of this solution is the lack of protection of the subchondral bone area.For this purpose,we designed and fabricated a 3D-printed metal-support prosthesis with good biocompatibility and osseointegration,which allows effective reconstruction of the tumor cavity while protecting the subchondral bone.Methods From June 2018 to January 2021,9 patients with distal femoral Campanacci gradeⅠorⅡGCTB underwent expanded intralesional curettage followed by reconstruction with 3D-printed metal-supported prosthesis combined with subarticular surface autogenous bone graft.Preoperative assessment of knee pain,function and subchondral bone integrity was performed as baseline information,and a custom prosthesis was made for each patient based on his or her 3D-CT data.Postoperatively,all patients were followed up periodically for postoperative knee pain,knee function,thickness of the subchondral bone layer,healing of the host bone with the autologous implant,and bone ingrowth of the autologous implant and host bone on the surface of the prosthesis to assess clinical and imaging prognosis.Results All patients were followed up for 18 to 42 months(mean,30.8±7.5 months).The preoperative percentage of affected subchondral bone and subchondral bone thickness were(31.8±9.6)%(range:18.2%-50.2%)and(2.2±0.8)mm(range:1.2-4.0 mm),respectively.At the final follow-up,the knee VAS score was lower[0 vs.(4.8±2.2)];the MSTS score was significantly higher[(26.7±2.4)vs.(18.8±3.7)];and the range of knee flexion was improved[(122.8±9.1)°vs.(108.3±6.1)°]as compared with that before surgery.In addition,the mean subchondral bone thickness of patients increased to(10.9±1.3)mm(range:9.1-12.1 mm)at the last follow-up.At the final follow-up,patients’ROM,VAS scores,MSTS scores,and subchondral bone thickness were statistically different compared to the data preoperative(P<0.001).In all patients,the subchondral bone graft healed with the host bone and the bone on the surface of the prosthesis grew in well.There was no local recurrence of tumor or distant metastasis to the lung;no postoperative complications occurred.Conclusions 3D-printed metalsupported prosthesis reconstruction has unique advantages over traditional cemented bone reconstruction,such as good biocompatibility,osseointegration ability and subchondral bone protection.The early clinical outcomes of patients with Campanacci gradeⅠor gradeⅡGCTB of the distal femur treated with 3D-printed metal-supported prosthesis combined with subarticular surface autogenous bone graft are satisfactory.