Kolcun John Paul G, Ghobrial George M, Crandall Kenneth M, Chang Ken Hsuan-Kan, Pacchiarotti Giacomo, Wang Michael Y
Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, Florida.
Department of Neurological Surgery, National Yang-Ming University School of Medicine, Taipei, Taiwan.
Int J Spine Surg. 2019 Aug 31;13(4):321-328. doi: 10.14444/6044. eCollection 2019 Aug.
We have previously reported the use of a minimally invasive allograft-filled expandable meshed-bag containment system in the lumbar spine. Subsidence has not been reported with this device. In this retrospective case series, we describe subsidence after lumbar interbody fusion using this device, with 12-month minimum radiographic follow-up.
Consecutive adult patients that underwent 1- or 2-level interbody fusion with at least 1 year of follow-up were included in this study. Preoperative, postoperative, and final follow-up lumbar radiographs were analyzed to measure disc height at the anterior and posterior margins of the disc space, as well as the neuroforaminal height.
Forty-one patients were identified, with a mean age of 63.4 years (± 11.8). A total of 61 levels were treated, with successful fusion observed in 54 levels (88.5%). The mean radiographic follow-up was 24.3 months (± 11.2). The mean disc height pre- and postoperatively was 6.9 mm (± 3.2) and 10.1 mm (± 2.9, < .001), respectively. The mean disc height at final follow-up was 8.3 mm (± 2.4). Average disc height subsidence was 1.8 mm (± 1.7, < .001). Overall, average disc height increased by a net 1.3 mm (± 2.5, < .001). The mean neuroforaminal height pre- and postoperatively was 18.0 mm (± 3.3) and 20.7 mm (± 3.6, < .001), respectively. The mean neuroforaminal height at final follow-up was 19.2 mm (± 3.4). Average neuroforaminal height subsidence was 1.3 mm (± 3.4, = .012). Overall, average neuroforaminal height increased by a net 1.7 mm (± 2.8, = .004). No significant difference in subsidence was observed between 1- and 2-level surgeries.
An expandable allograft containment system is a feasible alternative for lumbar interbody fusion. Due to its biologic and mechanical nature, the surgeon using such constructs should account for an anticipated average of 18% loss of interbody height due to subsidence during the bony remodeling/fusion process.
我们之前报道过在腰椎使用一种微创的同种异体骨填充可扩张网袋容纳系统。尚未有关于该装置下沉的报道。在这个回顾性病例系列中，我们描述了使用该装置进行腰椎椎间融合术后的下沉情况，至少有12个月的影像学随访。
本研究纳入了连续接受1或2节段椎间融合且至少随访1年的成年患者。分析术前、术后及最终随访时的腰椎X线片，以测量椎间隙前缘和后缘的椎间盘高度以及神经孔高度。
共确定41例患者，平均年龄63.4岁（±11.8）。共治疗61个节段，54个节段观察到成功融合（88.5%）。影像学平均随访时间为24.3个月（±11.2）。术前和术后的平均椎间盘高度分别为6.9mm（±3.2）和10.1mm（±2.9，P<0.001）。最终随访时的平均椎间盘高度为8.3mm（±2.4）。平均椎间盘高度下沉为1.8mm（±1.7，P<0.001）。总体而言，平均椎间盘高度净增加1.3mm（±2.5，P<0.001）。术前和术后的平均神经孔高度分别为18.0mm（±3.3）和20.7mm（±3.6，P<0.001）。最终随访时的平均神经孔高度为19.2mm（±3.4）。平均神经孔高度下沉为1.3mm（±3.4，P=0.012）。总体而言，平均神经孔高度净增加1.7mm（±2.8，P=0.004）。1节段和2节段手术之间在下沉方面未观察到显著差异。
可扩张同种异体骨容纳系统是腰椎椎间融合的一种可行替代方案。由于其生物学和力学特性，使用这种结构的外科医生应考虑到在骨重塑/融合过程中由于下沉预计椎间高度平均损失18%。
