Staudt Michael D, Rabin Doron, Baaj Ali A, Crawford Neil R, Duggal Neil
1Department of Clinical Neurological Sciences, London Health Sciences Centre, Western University, London, Ontario, Canada.
2St. Luke's University Health Network, Bethlehem, Pennsylvania.
J Neurosurg Spine. 2018 Nov 1;29(5):515-524. doi: 10.3171/2018.3.SPINE171248. Epub 2018 Aug 31.
OBJECTIVEThere are limited data regarding the implications of revision posterior surgery in the setting of previous cervical arthroplasty (CA). The purpose of this study was to analyze segmental biomechanics in human cadaveric specimens with and without CA, in the context of graded posterior resection.METHODSFourteen human cadaveric cervical spines (C3-T1 or C2-7) were divided into arthroplasty (ProDisc-C, n = 7) and control (intact disc, n = 7) groups. Both groups underwent sequential posterior element resections: unilateral foraminotomy, laminoplasty, and finally laminectomy. Specimens were studied sequentially in two different loading apparatuses during the induction of flexion-extension, lateral bending, and axial rotation.RESULTSRange of motion (ROM) after artificial disc insertion was reduced relative to that in the control group during axial rotation and lateral bending (13% and 28%, respectively; p < 0.05) but was similar during flexion and extension. With sequential resections, ROM increased by a similar magnitude following foraminotomy and laminoplasty in both groups. Laminectomy had a much greater effect: mean (aggregate) ROM during flexion-extension, lateral bending, and axial rotation was increased by a magnitude of 52% following laminectomy in the setting of CA, compared to an 8% increase without arthroplasty. In particular, laminectomy in the setting of CA introduced significant instability in flexion-extension, characterized by a 90% increase in ROM from laminoplasty to laminectomy, compared to a 16% increase in ROM from laminoplasty to laminectomy without arthroplasty (p < 0.05).CONCLUSIONSForaminotomy and laminoplasty did not result in significant instability in the setting of CA, compared to controls. Laminectomy alone, however, resulted in a significant change in biomechanics, allowing for significantly increased flexion and extension. Laminectomy alone should be used with caution in the setting of previous CA.
关于在先前颈椎关节成形术（CA）背景下进行翻修后路手术的影响，相关数据有限。本研究的目的是在分级后路切除的情况下，分析有无CA的人体尸体标本的节段生物力学。
将14个尸体颈椎（C3 - T1或C2 - 7）分为关节成形术组（ProDisc - C，n = 7）和对照组（完整椎间盘，n = 7）。两组均进行了连续的后路结构切除：单侧椎间孔切开术、椎板成形术，最后是椎板切除术。在屈伸、侧弯和轴向旋转过程中，在两种不同的加载装置中对标本进行顺序研究。
人工椎间盘植入后，在轴向旋转和侧弯时，相对于对照组，活动范围（ROM）减小（分别为13%和28%；p < 0.05），但在屈伸时相似。随着连续切除，两组在椎间孔切开术和椎板成形术后ROM增加幅度相似。椎板切除术的影响更大：在CA情况下，椎板切除术后屈伸、侧弯和轴向旋转时的平均（总计）ROM增加了52%，而无关节成形术时增加了8%。特别是，在CA情况下进行椎板切除术会在屈伸时引入显著的不稳定，其特征是从椎板成形术到椎板切除术ROM增加了90%，而无关节成形术时从椎板成形术到椎板切除术ROM增加了16%（p < 0.05）。
与对照组相比，在CA情况下，椎间孔切开术和椎板成形术不会导致显著的不稳定。然而，单独的椎板切除术会导致生物力学的显著变化，使屈伸明显增加。在先前有CA的情况下，应谨慎使用单独的椎板切除术。
