Orthopedic Surgery Service, Department of Surgery, Madigan Army Medical Center, 9040A Fitzsimmons Ave., Tacoma, WA 98467, USA.
Spine J. 2009 Nov;9(11):910-5. doi: 10.1016/j.spinee.2009.08.459.
Minimally invasive spine surgery continues to be a growing trend for orthopedic and neurosurgical spinal interventions. Technological advances have allowed surgeons to perform L5-S1 fusions via posterolateral or anterior approaches through less invasive techniques. The development of the AxiaLIF system (TranS1, Inc., Wilmington, NC) is predicated on the application of minimally invasive techniques to attain fusion at L5-S1 and L4-S1 levels with a novel corridor of approach, described as the presacral "safe zone."
The authors describe an alternative approach for removing a L5-S1 transsacral implant that was placed through a percutaneous paracoccygeal approach using the presacral safe zone. The purpose of this technical note is to demonstrate that use of the previous percutaneous presacral tract, as recommended by the manufacturer, is not mandatory. In cases of anterior pseudarthrosis following this device, a paramedian retroperitoneal approach to L5-S1 not only allows for adequate visualization for revision but also provides adequate and safe caudal exposure over the sacral promontory to remove the implant through its previous osseous path.
STUDY DESIGN/SETTING: This technical note highlights the concerns for revision of the AxiaLif (TranS1) screw through the presacral scarred tract.
The AxiaLif (TranS1), used in this case is an alternative method to anterior, posterior, or transforaminal lumbar interbody fusion. Removal of this implant for pseudarthrosis was performed through a paramedian retroperitoneal approach with caudal extension. After anterior discectomy, the AxiaLif screw was removed via manipulation through the disc space and delivered through the sacrum. This was followed by complete discectomy and bone grafting of the voids left in the L5 and sacral vertebral bodies. Standard anterior lumbar interbody reconstruction was then performed using a polyetheretherketone implant followed by revision of the pedicle screw construct posteriorly.
Preoperative symptoms were resolved in the immediate postoperative period secondary to the immediate stability afforded by the revision of the loose implants. Fusion was achieved within 6 months and confirmed with fine-cut computed tomography images.
This novel technique of avoiding a scarred down presacral corridor in the hands of surgeons unfamiliar with the technique allows for safe removal of the AxiaLif (TranS1) implant coupled with revision to anterior lumbar interbody fusion through the same incision.
微创脊柱手术在骨科和神经外科脊柱介入治疗中仍是一种不断发展的趋势。技术的进步使外科医生能够通过经皮后路或前路微创技术进行 L5-S1 融合。AxiaLIF 系统（TranS1，Inc.，北卡罗来纳州威尔明顿）的开发基于微创技术在 L5-S1 和 L4-S1 水平上实现融合的应用，其采用了一种新的入路通道，称为经骶前“安全区”。
作者描述了一种通过经皮骶旁旁正中入路应用经骶前安全区移除 L5-S1 经骶植入物的替代方法。本技术说明的目的是证明制造商推荐的先前经皮骶前通道的使用并非强制性的。在该设备后出现前假关节的情况下，经旁正中腹膜后入路至 L5-S1 不仅可以为翻修提供充分的可视化，还可以在骶骨岬上方提供充分和安全的尾侧暴露，通过先前的骨道移除植入物。
研究设计/设置：本技术说明强调了对经骶前瘢痕通道修正 AxiaLif（TranS1）螺钉的关注。
在此病例中使用的 AxiaLif（TranS1）是一种替代前路、后路或经椎间孔腰椎融合术的方法。通过经旁正中腹膜后入路进行尾侧延长以移除该植入物用于治疗假关节。在进行前路椎间盘切除术后，通过椎间盘间隙进行操作并通过骶骨输送移除 AxiaLif 螺钉。随后进行彻底的椎间盘切除和填充 L5 和骶骨椎体遗留的空洞的骨移植。然后使用聚醚醚酮植入物进行标准的前路腰椎椎间融合重建，随后对后路的椎弓根螺钉结构进行修正。
术后即刻，由于翻修后提供的即刻稳定性，术前症状得到缓解。在 6 个月内实现融合，并通过精细切割计算机断层扫描图像确认。
对于不熟悉该技术的外科医生，避免在手中使用经骶前瘢痕通道的新技术允许安全移除 AxiaLif（TranS1）植入物，并通过相同的切口进行前路腰椎椎间融合重建。
