3D打印可动人工颈椎假体置入治疗脊髓型颈椎病:国际首例报道

Three-dimensional printing motion-preserving cervical joint system implantation for treatment of cervical myelopathy:the first case report

背景:目前,颈椎椎体切除减压后必须施行融合手术重建颈椎的稳定性,但融合牺牲了手术节段颈椎的活动功能,同时众多文献报道融合术后存在潜在的局部应力转移、邻近节段退变等远期问题。作者在颈椎前路椎体、椎间盘次全切后保留颈椎运动单元活动功能方面做了一些研究与探索,结合3D打印技术研制出了"人工颈椎椎体-椎间盘复合体",简称可动人工颈椎。目的:探讨3D打印可动人工颈椎椎体置入治疗2例颈段脊髓压迫症患者的近期临床疗效与术后颈椎活动度保留情况。方法:为了保留椎体次全切除术后颈椎节段运动功能,2020年12月采用自主研发的3D打印可动人工颈椎椎体置入到2例因巨大椎间盘脱出行椎体次全切除的颈椎椎间缺损区。截止投稿时2021年4月共随访16周,分别于术后1,6,12,16周时采用目测类比评分及JOA评分对患者疼痛程度及神经功能恢复情况进行评估;采用动力位X射线片及三维CT等影像学技术评价植假体位置及颈椎节段运动功能保留情况,同时观察并记录患者随访期间手术相关并发症发生情况。研究经西安国际医学中心医院伦理委员会批准,伦理批件号:202012。结果与结论:(1)2例患者术后次日疼痛、麻木均明显减轻,四肢肌力部分恢复。(2)术后1,6,12,16周随访时,患者四肢肌力、目测类比评分、JOA评分均较术前明显改善,头颈部活动功能良好。随访期间未发生切口内血肿、喉返神经损伤、食管损伤、脑脊液漏、切口感染、螺钉松动等情况。(3)术后1,6,12,16周随访时,X射线片检查可见患者颈椎生理曲度恢复良好,椎间高度维持良好;3D-CT显示减压效果良好,人工椎体部件与周边颈椎骨质贴合良好;动力位X射线片可见假体终板部件在屈伸及侧屈活动时具有一定的角度开合变化,无颈椎失稳,提示假体保留了部分颈椎运动功能。(4)结果提示,可动人工颈椎椎体能够在重建颈椎稳定性的基础上保留椎间活动功能。

BACKGROUND:At present,fusion surgery must be performed to reconstruct the stability of the cervical spine after anterior cervical corpectomy.However,fusion sacrifices the mobility of the surgical segment of the cervical spine.Simultaneously,many articles report the potential long-term problems such as adjacent segment degeneration in fusion surgery.We have done some research and exploration on the preservation of cervical segmental motor function after anterior cervical corpectomy.Combined with three-dimensional printing technology,we have developed"artificial cervical vertebrae-intervertebral disc complex",referred to as the motion-preserving cervical joint system.OBJECTIVE:To explore the short-term clinical effect of three-dimensional printing motion-preserving cervical joint system implantation in the treatment of two patients with cervical spondylotic myelopathy.METHODS:In view of the loss of motor function of cervical spine segments and the degeneration of adjacent segments after traditional anterior cervical corpectomy operation,in December 2020,a self-developed three-dimensional printing motion-preserving cervical joint system implantation technology was used to treat two patients with cervical spondylotic myelopathy.The patients were followed up for 16 weeks at the time of submission(April 2021).Visual analogue scale score and JOA score were used to evaluate the patient’s pain and neurological recovery at 1,6,12,and 16 weeks after the operation.Imaging techniques such as dynamic position X-rays and three-dimensional CT were used to evaluate the position of prosthesis and the preservation of cervical spine motion function.The occurrence of surgery-related complications was observed and recorded during the patient follow-up period.This study was approved by the Ethics Committee of Xi’an International Medical Center Hospital(approval No.202012).RESULTS AND CONCLUSION:(1)The pain and numbness of the two patients were significantly reduced the next day after the operation,and the muscle strength of the limbs was partially restored.(2)At 1,6,12,and 16 weeks postoperative follow-up,the patient’s limb muscle strength,visual analogue scale score,and JOA score were significantly improved compared with preoperatively,and the head and neck movement function was good.During the follow-up,no intra-incision hematoma,recurrent laryngeal nerve injury,esophageal injury,cerebrospinal fluid leakage,incision infection,or screw loosening occurred.(3)At 1,6,12,and 16 weeks postoperative follow-up,X-ray examination showed that the cervical spine physiological curvature was well restored,and the intervertebral height was maintained well.3 D-CT showed that the prosthesis components and the cervical spine bones were in good fit.The dynamic position X-ray showed that the prosthesis endplate component had a certain angle of opening and closing changes during flexion,extension and lateral flexion,and there was no cervical spine instability,indicating that the prosthesis retained part of the cervical spine motion function.(4)It is concluded that motion-preserving cervical joint system can retain the function of intervertebral movement on the basis of reconstructing the stability of the cervical spine.