INTRODUCTION Dynamic stabilization of the spine has been performed since the 1990s with the double purpose of restoring spinal segmental stability and allowing residual movement at the operated level. When we take into account the different motion-preserving devices and the spinal areas where they are applied, we can identify three categories of spinal implants: anterior cervical, anterior lumbar, and posterior lumbar. However, as in all prosthetic procedures performed in orthopedic surgery, the life span of a joint replacement device is a central topic of discussion, and this is true also for spinal dynamic devices, being revision surgery a complex procedure in specific cases. MATERIALS AND METHODS We performed a literature review on the different dynamic spinal implants and the most common causes of failure, providing clinical cases as illustrative options for revision surgery. RESULTS The review of the literature showed a 11.3% to 22.6% revision rate in posterior lumbar dynamic systems, with a peak of 40.6% in case of adjacent segment disease. In lumbar TDRs, infection and severe dislocations are the most frequent causes of anterior revisions, while posterior pedicle screw fixation could be a suitable option in minimal subsidence or TDR displacement. An algorithm for the planning of revision surgery is proposed. CONCLUSIONS Surgical revision of spinal dynamic implants could be a demanding surgery especially in anterior approaches. Anterior cervical revision remains globally safe, but careful preoperative evaluation of vessels and ureter are suggested to avoid intraoperative complications in the lumbar spine. In posterior revision, a proper sagittal alignment of the spine should be restored. These slides can be retrieved under Electronic Supplementary Material.

中文翻译：

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脊柱动力植入物的翻修手术：文献综述和算法建议。

简介自1990年代以来，就一直在进行脊柱的动态稳定，其双重目的是恢复脊柱节段的稳定性，并在手术时允许残余运动。当我们考虑到不同的运动保持装置和应用它们的脊椎区域时，我们可以识别出三类脊柱植入物：前颈椎，前腰椎和后腰椎。但是，正如在整形外科手术中执行的所有修复手术一样，关节置换装置的使用寿命是讨论的中心话题，对于脊柱动力装置也是如此，在特定情况下翻修手术是一项复杂的手术。材料和方法我们对不同的动力性脊柱植入物和最常见的失败原因进行了文献综述，提供临床案例作为翻修手术的说明性选择。结果文献综述显示，后腰椎动力系统的翻修率为11.3％至22.6％，在邻近节段疾病的情况下最高为40.6％。在腰部TDR中，感染和严重脱位是前翻的最常见原因，而后椎弓根螺钉固定可能是最小下陷或TDR移位的合适选择。提出了修复手术计划的算法。结论脊柱动力植入物的外科手术修订可能是一项艰巨的手术，尤其是在前路手术中。颈椎前路翻修总体上仍是安全的，但建议对血管和输尿管进行术前仔细评估，以避免术中腰椎并发症。在后修订中，应恢复脊柱的正确矢状对齐。这些幻灯片可以在电子补充材料下找到。