In the last decades, several interspinous process devices were designed as a minimally invasive treatment option for spinal stenosis. In order to minimise surgical trauma, interspinous process devices were recently discussed as an alternative posterior fixation in vertebral interbody fusions. Therefore, the purpose of this study was to evaluate the effect of a newly designed interspinous device with polyester bands (PBs) on range of motion (RoM) and centre of rotation (CoR) of a treated motion segment in comparison with an established interspinous device with spikes (SC) as well as with pedicle screw instrumentation in lumbar fusion procedures. Flexibility tests with an applied pure moment load of 7.5 Nm were performed in six monosegmental thoracolumbar functional spinal units (FSUs) in the following states: (a) native, (b) native with PB device, (c) intervertebral cage with PB device, (d) cage with SC and (e) cage with internal fixator. The resulting RoM was normalised to the native RoM. The CoR was determined of X-ray images taken in maximal flexion and extension during testing. In flexion and extension, the PB device without and with the cage reduced the RoM of the native state to 58% [standard deviation (SD) 17.8] and 53% (SD 15.7), respectively. The SC device further reduced the RoM to 27% (SD 16.8), while the pedicle screw instrumentation had the most reducing effect to 17% (SD 17.2) (p < 0.01). In lateral bending and axial rotation, the interspinous devices had the least effect on the RoM. Compared to the native state, for all instrumentations the CoR showed a small shift towards cranial. In the anterior-posterior direction, the SC device and the pedicle screw instrumentation shifted the CoR towards the posterior wall. The interspinous devices significantly reduced the RoM in flexion/extension, while in axial rotation and lateral bending only the internal fixator had a significant effect on the RoM.

中文翻译：

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棘突间装置的功能和射线照相评估，作为腰椎椎间融合手术的辅助手段。

在过去的几十年中，几种棘突间处理装置被设计为脊椎狭窄的微创治疗选择。为了使外科手术创伤最小化，最近讨论了棘突间装置作为椎体椎间融合器的一种后路固定方法。因此，本研究的目的是评估新设计的带有聚酯带（PBs）的棘突间器械与已建立的棘突间器械相比，对经治疗的运动节段的运动范围（RoM）和旋转中心（CoR）的影响在腰椎融合手术中使用尖钉（SC）以及椎弓根螺钉器械。在以下状态下的六个单节胸腰椎功能性脊柱神经节单位（FSU）中进行了7.5 Nm的纯力矩载荷下的柔韧性测试：（a）天然，（b）PB装置天然，（c）带PB装置的椎间笼，（d）带SC的笼和（e）带内部固定器的笼。将生成的RoM标准化为本地RoM。测定在测试过程中以最大屈曲和伸展度拍摄的X射线图像的CoR。在弯曲和伸展过程中，不带和带笼的PB设备分别将原始状态的RoM降低到58％[标准偏差（SD）17.8]和53％（SD 15.7）。SC设备将RoM进一步降低到27％（SD 16.8），而椎弓根螺钉器械的最大降低效果是17％（SD 17.2）（p <0.01）。在横向弯曲和轴向旋转中，棘突间装置对RoM的影响最小。与原始状态相比，所有仪器的CoR均显示出向颅骨的微小变化。在前后方向上 SC设备和椎弓根螺钉器械将CoR移向后壁。棘突间装置显着降低了RoM的屈曲/伸展，而在轴向旋转和横向弯曲时，仅内部固定器对RoM产生了显着影响。