Mattei Tobias A, Teles Alisson R, Dinh Dzung H
Department of Neurosurgery, Brain and Spine Center/InvisionHealth, 400 International Drive, Buffalo, NY, 14221, USA.
Neurosurgery Unit, Hospital São José-Santa Casa de Porto Alegre, Porto Alegre, Brazil.
Eur Spine J. 2020 May;29(5):943-952. doi: 10.1007/s00586-015-4358-3. Epub 2016 Jan 5.
Zero-profile (also called self-locking, anchored or stand-alone cages) have been recently proposed as an interesting alternative for anterior cervical discectomy and fusion (ACDF), as they are supposed to reduce the rates of post-operative cage extrusion without necessarily incurring in the additional surgical time and increased rates of dysphagia associated with plating. Nevertheless, the exact indications of zero-profile anchored cages have not yet been established in the literature.
To report the first case of a vertebral body fracture between the blades of zero-profile anchored cages after ACDFs in adjacent levels and to review the available literature on hardware-related complications after multi-level ACDFs with zero-profile anchored cages.
Case report and systematic literature review.
The authors report the first case of a vertebral body fracture between the blades of zero-profile anchored cages after ACDFs in adjacent levels. The patient presented with refractory mechanical neck pain at the 1-month post-operative follow-up, ultimately requiring a posterior instrumented fusion. A comprehensive systematic literature review on the available data regarding the safety, complications as well as radiological and clinical outcomes of zero-profile anchored cages is also performed.
In the reported case, the use of zero-profile anchored cages in adjacent levels on the cervical spine led to a fracture of the vertebral body between the cages at the 1-month follow-up, with anterior avulsion of the part of the vertebral body where the blades from the two cages converged. According to the systematic literature review which included 409 patients from 10 different clinical series (with a total cumulative follow-up of approximately 535 patients-year), there were only two reported hardware-related complications after ACDF with zero-profile anchored cages, none of them involving fracture at the level of convergence of blades or screws.
Although hardware-related complications after the use of zero-profile anchored cages seem to be rare events, future biomechanical and clinical studies are warranted in order to evaluate the safety of employing such devices for the treatment of multilevel degenerative disc disease in the cervical spine.
零轮廓（也称为自锁、锚定或独立式椎间融合器）最近被提议作为颈椎前路椎间盘切除融合术（ACDF）的一种有趣替代方案，因为它们被认为可以降低术后椎间融合器脱出率，且不一定会增加手术时间和与钢板相关的吞咽困难发生率。然而，零轮廓锚定椎间融合器的确切适应证在文献中尚未明确。
报告相邻节段ACDF术后零轮廓锚定椎间融合器叶片间椎体骨折的首例病例，并回顾有关零轮廓锚定椎间融合器多级ACDF术后硬件相关并发症的现有文献。
病例报告和系统文献综述。
作者报告相邻节段ACDF术后零轮廓锚定椎间融合器叶片间椎体骨折的首例病例。患者术后1个月随访时出现难治性机械性颈部疼痛，最终需要后路器械融合术。还对有关零轮廓锚定椎间融合器的安全性、并发症以及影像学和临床结果的现有数据进行了全面的系统文献综述。
在所报告的病例中，颈椎相邻节段使用零轮廓锚定椎间融合器导致术后1个月随访时椎间融合器间椎体骨折，两个椎间融合器叶片汇聚处的椎体部分出现前方撕脱。根据系统文献综述，该综述纳入了来自10个不同临床系列的409例患者（总累积随访约535患者年），ACDF使用零轮廓锚定椎间融合器后仅报告了两例硬件相关并发症，均未涉及叶片或螺钉汇聚处的骨折。
尽管使用零轮廓锚定椎间融合器后硬件相关并发症似乎很少见，但未来仍需要进行生物力学和临床研究，以评估使用此类装置治疗颈椎多节段退变性椎间盘疾病的安全性。
