Zhang Feng, He Xi-Jing, Liu Jian-Tao, Wang Rui, Qin Jie, Zang Quan-Jin, Zhang Ting, Liu Zhi-Yu
Department of Orthopaedics, Xi'an Fourth Hospital, Xi'an 710004, Shaanxi, China.
Department of Orthopaedics, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi, China.
Zhongguo Gu Shang. 2024 Mar 25;37(3):281-7. doi: 10.12200/j.issn.1003-0034.20221073.
Mobile artificial lumbar complex (MALC) which suitable for reconstruction after subtotal lumbar resection in goats was developed,and to test stability of the complex and postoperative lumbar segmental motor function.
Eighteen male boer goats aged from 1 to 2 years old (weighted from 35 to 45 kg) were selected and divided into control group,fusion group and non-fusion group,with 6 goats in each group. According to preoperative CT scans and MRI examinations of lumbar,the goat MALC was designed and performed by 3D printed for non-fusion group. Operation was performed on three groups respectively,and only vertebral body and disc were exposed in control group. In fusion group,L part of vertebral body and the upper and lower complete disc tissues were removed,and the lumbar spine bone plate fixation was performed with titanium mesh bone grafting. In non-fusion group,vertebral body and disc were removed in the same way,and MALC was implanted. AP and lateral X-rays of lumbar vertebrae in goat were taken at 6 months after surgery,in order to understand whether the plant was dislocated,displaced and fractured. Biomechanical tests were performed on the specimens by mechanical instrument to measure range of motion (ROM) of L,L,L intervertebral space and the overall ROM of L lumbar vertebrae.
MALC of lumbar vertebra was designed by 3D printing,and its component artificial vertebrae and upper and lower artificial end plates were manufactured. The semi-spherical structure was fabricated by precision lathe using high-crosslinked polyethylene material,and the prosthesis was assembled. Postoperative AP and lateral X-rays of lumbar vertebra at 6 months showed the implant position of implant and MALC were good without displacement and dislocation. In vitro biomechanical test of lumbar vertebrae specimens:(1) There were no statistical significance in ROM of lumbar intervertebral space flexion and extension,lateral flexion and rotation on L and L,between non-fusion group and control group (>0.05),while ROM of fusion group was significantly reduced compared with the other two groups (<0.05). There were no significant difference in ROM of L intervertebral flexion and extension,lateral flexion and rotation between non-fusion group and control group (>0.05),while fusion group was significantly increased compared with the other two groups (<0.001). (2) There was no significant difference in overall lumbar ROM of L (> 0.05).
The individual MALC could restore intervertebral height of lumbar vertebra while maintaining the stability of lumbar vertebra and re-establishing motor function of lumbar space.
研制适合山羊腰椎次全切除术后重建的可移动人工腰椎复合体（MALC），并测试该复合体的稳定性及术后腰椎节段运动功能。
选取18只1～2岁雄性波尔山羊（体重35～45 kg），分为对照组、融合组和非融合组，每组6只。根据术前山羊腰椎CT扫描和MRI检查结果，为非融合组设计并通过3D打印制作山羊MALC。分别对三组进行手术，对照组仅暴露椎体和椎间盘。融合组切除部分椎体及上下完整椎间盘组织，采用钛网植骨行腰椎椎板固定。非融合组以同样方式切除椎体和椎间盘，植入MALC。术后6个月拍摄山羊腰椎正侧位X线片，了解植入物是否脱位、移位及骨折。用机械仪器对标本进行生物力学测试，测量L、L、L椎间隙的活动度（ROM）及L腰椎的整体ROM。
通过3D打印设计出腰椎MALC，制作出其组成部分人工椎体及上下人工终板。采用高交联聚乙烯材料经精密车床加工制成半球形结构，组装假体。术后6个月腰椎正侧位X线片显示植入物及MALC植入位置良好，无移位和脱位。腰椎标本体外生物力学测试：（1）非融合组与对照组L、L椎间隙屈伸、侧屈及旋转ROM比较，差异无统计学意义（>0.05），融合组与其他两组比较，ROM显著降低（<0.05）。非融合组与对照组L椎间隙屈伸、侧屈及旋转ROM比较，差异无统计学意义（>0.05），融合组与其他两组比较，ROM显著增加（<0.001）。（2）L腰椎整体ROM比较，差异无统计学意义（>0.05）。
个体化MALC在维持腰椎稳定性及重建腰椎节段运动功能的同时，可恢复腰椎椎间隙高度。
