3D打印个体化人工椎体在多节段脊柱肿瘤切除后脊柱稳定性重建中的应用

The effect of 3D printed individualized artificial vertebra on spinal stability reconstruction after multi-level spinal tumor resection: an exploratory clinical study

中文关键词:  脊柱肿瘤  3D打印  多节段全椎体切除术  人工椎体

英文关键词:Spinal tumor  3D printing  Multilevel vertebrectomy  Artificial vertebral body

中文摘要:

  【摘要】 目的：探讨3D打印个体化人工椎体在多节段脊柱肿瘤切除后脊柱稳定性重建中应用的安全性和有效性。方法：回顾性分析2017年5月~2019年12月在我院行多节段脊柱肿瘤全切并行3D打印人工椎体脊柱稳定性重建的患者9例，其中男性3例，女性6例；年龄25~64岁，平均41.7±10.5岁，随访18.3±11.4个月（6~36个月）。9例均为原发肿瘤：T5~T7骨母细胞瘤术后复发1例，T7~T8上皮样血管肉瘤1例，T10~T11未分化小圆细胞肉瘤1例，T11~L1软骨肉瘤1例，骨巨细胞瘤5例（T6~T8共2例，T2~T3、T4~T5、T11~L1各1例）。依据肿瘤位置及周围软组织侵袭程度，采取单纯后路手术方式8例，前后路联合手术方式1例行多节段全椎体切除，并通过激光选区融化技术构建个体化3D打印人工椎体进行脊柱稳定性重建。记录手术时间、出血量，通过术后X线片（1个月、3个月、6个月、12个月）及CT（6个月、12个月、24个月）定期复查，之后每6个月复查1次。应用Brantigan & Steffee脊柱融合分级评估人工椎体稳定性、界面骨融合情况，手术前及术后1周进行Frankel神经功能评分及疼痛视觉模拟（visual analogue scale，VAS）评分。术后定期观察肿瘤是否复发生原位复发、远处转移以及患者生存情况。结果：所有患者均成功接受多节段脊柱肿瘤切除3D打印人工椎体脊柱稳定性重建术，其中2个节段椎体切除4例，3个节段椎体切除5例。患者手术时间433.3±174.6min（235~740min），术中出血量4816.7±3221.2ml（1000~14000ml）。术前的VAS评分4.1±1.1分，术后7d患者的VAS评分1.2±0.4分，差异具有统计学意义（P<0.001）。术前Frankel分级为D级的3例患者术后7d时有2例恢复到E级，1例无明显变化，6例E级患者无明显变化。随访期内3D打印人工椎体与邻近椎体匹配情况良好，无松动、下沉及移位，同时未出现断钉、断棒等内固定失败情况。术后6个月，人工椎体与邻近椎体接触紧密，开始出现界面骨长入，术后12个月，人工椎体与邻近椎体出现骨性连接，发生骨性融合。随访期内7例患者无肿瘤复发转移，1例软骨肉瘤患者术后16个月局部复发，安罗替尼治疗后肿瘤无恶化，1例上皮样血管肉瘤患者全身多发转移于术后18个月死亡，患者中位生存期18个月。结论：3D打印个体化人工椎体可以满足多节段脊柱肿瘤切除后脊柱稳定性重建的要求，精确恢复椎体连续性，精准匹配相邻椎体，自身孔隙结构利于骨的长入，是一种多节段脊柱肿瘤切除后理想的脊柱稳定性重建方法。

英文摘要:

  【Abstract】 Objectives: To investigate the safety and effectiveness of 3D printed individualized artificial vertebra on spinal stability reconstruction after multi-level spinal tumor resection. Methods: From May 2017 to December 2019, 9 patients who underwent multi-level total vertebrectomy and spinal reconstruction using individualized 3D printed artificial vertebralbody were analyzed retrospectively. There were 3 males and 6 females, with a mean age of 41.7±10.5 years(range, 20-57). 9 primary tumors were included. Based on the tumor location and surrounding soft tissue invasion range, posterior approach(8 cases) and combined anterior and posterior approach(1 case) were adopted for total vertebral resection, with 3D printed artificial vertebral body for reconstruction. The mean follow-up period was 18.3±11.4 months(range, 6-36 months). 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, metastasis and survival of patients were collected and analyzed. Meanwhile, according to Brantigan & Steffee classification of spinal fusion, X-ray(1 month, 3 months, 6 months, 12 months, and every 6 month) and CT(6 months, 12 months, 24 months, and every 6 month) were used to evaluate the stability of artificial vertebral body and bone fusion during the follow-up. Results: All 9 patients were successfully treated with 3D printed artificial vertebral body reconstruction, among them 4 cases underwent 2 levels vertebrectomy and 5 cases underwent 3 levels vertebrectomy. The mean operation time was 433.3 minutes(range, 235-740 minutes), and the mean blood loss was 4816.7ml(range, 1000-14000ml). Compared to the preoperative VAS score(4.1±1.1), the score at 7 days postoperative(1.2±0.4) was significantly reduced(P<0.001). At 7 days postoperatively, for the 3 patients of Frankel grade D before operation, except 1 with no obvious change, the other 2 gradually recovered to grade E, and no obvious change was found in 6 grade E patients. During the follow-up, there was no loosening or displacement of the artificial vertebral body and no failure of internal fixation. Preliminary bone growth was found between the artificial vertebral body and the adjacent vertebral body 6 months after operation. The bone growth was more obvious at 12 months postoperatively, and the artificial vertebral body was fused with the adjacent vertebral bodies to form bone integration. There was no tumor recurrence and metastasis in 7 patients. One patient with chondrosarcoma developed local recurrence at 16 months after operation. A case of epithelioid angiosarcoma died at 18 months postoperatively. The median survival time was 18 months. Conclusions: 3D printed individualized artificial vertebral body can meet the requirements of spinal stability reconstruction after resection of multi-level spinal tumors. It can effectively restore the continuity of the spine, and precisely match the adjacent vertebral bodies. In addition, its own pore structure is conducive to bone growth. Therefore, it is an ideal spinal reconstruction method after multi-level spinal tumor resection.