新型3D打印个体化人工椎体在脊柱重建中的初步研究

Preliminary study on the a novel individualized 3D printing artificial vertebral body in spine reconstruction

目的探讨新型3D打印个体化人工椎体在脊柱重建中的优势,并对其重建效果进行临床评估。方法收集2017年1月至2018年12月行全椎体切除术后采用3D打印个体化人工椎体行脊柱重建的15例肿瘤患者的临床资料,其中男8例,女7例;年龄(39.5±13.4)岁(范围:20~57岁)。原发肿瘤12例,转移肿瘤3例。依据肿瘤位置及周围软组织侵及范围,采取单纯后路或前后路联合手术方式行全椎体切除,并进行3D打印人工椎体重建。分析手术时间、术中出血量、术后人工椎体稳定情况、与相邻椎体骨长入情况,手术前后神经功能改变情况、疼痛视觉模拟评分(visual analogue scale,VAS),局部控制情况及患者生存情况。结果本组15例的手术时间(412.0±166.1)min(范围:135~740 min);术中出血量(4140.0±3809.3)ml(范围:100~14000 ml);术后随访(23.2±7.0)个月(范围:12~35个月)。术前VAS评分(4.7±1.1)分,术后7 d(1.6±0.6)分,末次随访时(1.0±0.5)分,术后7 d及末次随访较术前的差异均有统计学意义(P<0.001)。术后7 d术前Frankel分级C级的3例逐渐恢复到D级,余12例D级和E级无变化,差异无统计学意义(Z=-1.732,P=0.083);术后末次随访时Frankel分级较术后7 d无明显变化。影像学表现:术后3个月时人工椎体与临近椎体已有初步的骨愈合;术后12个月时人工椎体和邻近椎体有大量骨连接形成,形成骨整合;术后24个月时可见人工椎体与邻近椎体骨整合更加确实。在随访期内人工椎体无松动移位,内固定无断裂失效。术中1例出现胸膜破裂,术后1例发生脑脊液漏,1例出现L5神经根麻痹,积极对症处理后均痊愈。1例血管内皮细胞瘤和1例上皮样血管肉瘤,分别于术后33个月和35个月死亡,1例软骨肉瘤术后16个月局部复发,服用安罗替尼治疗,肿瘤无进展,余12例无肿瘤复发及远处转移。结论利用3D打印个体化人工椎体对脊柱肿瘤切除后重建,有利于精确恢复脊柱连续性,提供更好的界面匹配,利于骨的长入,同时人工椎体植入后即刻及远期稳定性良好,可满足脊柱重建的需要。

Objective To explore the advantages of the novel individualized 3D printing artificial vertebral body in spine reconstruction and to evaluate its clinical effect.Methods From January 2017 to December 2018,the 15 patients who underwent total vertebrectomy and spine reconstruction with individualized 3D printing artificial vertebral body were analyzed retrospectively.There were 8 males and 7 females,with the mean age 39.5 years(range:20-57),including 12 primary tumors and 3 metastatic tumors.According to tumor location and surrounding soft tissue invasion range,simple posterior or combined anterior and posterior approach were used for total vertebral resection,and the defection was reconstructed by 3D printing artificial vertebral body.The operation time,intraoperative bleeding volume,postoperative stability of artificial vertebral body and bone ingrowth of adjacent vertebral body,preoperative and postoperative neurological changes,preoperative and postoperative VAS score,local control and survival of patients were analyzed.Results The mean operation time was 412.0 min(range:135-740 min),and the mean blood loss was 4140.0ml(range:100-14000 ml).The mean follow-up time was 23.2 months(range:12-35 months),and no one loss to follow-up.One case had pleural rupture,one case had cerebrospinal fluid leakage and one case had L5 nerve root palsy.All patients recovered after active symptomatic treatment.Compare with the preoperative VAS score(4.7±1.1),the differences of VAS score at 7 d postoperative and last follow-up(1.6±0.6 and 1.0±0.5)were significantly reduced(P<0.001).Three patients with Frankel grade C gradually recovered to grade D,and no change were found in grade D and Grade E patients,there was no significant improved at last follow-up.Preliminary bone growth was found between the artificial vertebral body and the adjacent vertebral body 3 months after operation.The bone growth was more obvious at 12 months post-operation,and the artificial vertebral body fused with the adjacent vertebral bodies to form bone integration.At 24 months post-operation,the integration of the artificial vertebral body was more accurate.During the follow-up period,there was no loosening or displacement of the artificial vertebral body and no failure of internal fixation.A case of hemangioendothelioma and a case of epithelioid angiosarcoma died at 33 months and 35 months postoperatively.One patient with chondrosarcoma had local recurrence at16 months post-operation.After treated with arotinib,the tumor did not progress.The other 12 patients had no tumor recurrence or distant metastasis.Conclusion After spinal tumor resection,individualized 3D printing artificial vertebral body can be used to accurate restoration of spinal continuity,and provide nice interface matching and bone growth between artificial vertebral body and the adjacent vertebral endplates.Moreover,the immediate and long-term stability of the artificial vertebral body can meet the needs of spinal reconstruction.