Biomechanical Changes of Degenerated Adjacent Segement and Intact lumbar Spine after lumbosacral Topping-off surgery: A Three-dimensional Finite Element Analysis

Abstract Background: Previous studies have revealed positive effect of Topping-off technique on upper adjacent segment after fusion surgery, while for the cases with fusion surgery on L5-S1 segment, owning maximal range of motion, and pre-exsiting degenerated upper adjacent disc, it is necessary to clarify the superiority of Topping-ff technique and the effect exerted on the lumbar spine. Methods: A young healthy male volunteer was selected for thin-slice CT scanning. Then the image information was imported into the computer to establish the whole lumbar spine model as the health model. The medium degeneration model of intervertebral disc was established by changing the material properties of L4-S1 disc on the basis of the health model, and the fusion model and Topping-off model were respectively established on the basis of the degenerated model. The variation trend of ROM of L2-L5 and the stress changes of L4-L5 intervertebral disc, nucleus pulposus and facet joints were calculated respectively. Results: The L4-L5 ROM of fusion model increased significantly but the ROM of L2-L3 and L3-L4 segments did not change significantly. Compared with the degenerated model, L4-L5 activity of the Topping-off model decreased, and ROM of the L2-L3 and L3-L4 increased to some extent in the flexion and extension positions. the stress on the disc, nucleus pulposus and facet joint of the fusion model L4-L5 increased in four positions of flexion, extension, rotation and bending compared with the degenerated model, while the fiber stress on the Topping-off model decreased significantly in all four positions. Conclusion: Topping-off technology can decrease the stress and ROM of the adjacent upper degenerated segment, and increase the ROM of other upper segments, thereby delaying the degeneration of upper adjacent segments and compensating the lumbar spine mobility.

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Biomechanical Changes of Degenerated Adjacent Segment and Intact lumbar Spine after lumbosacral Topping-off surgery: A Three-dimensional Finite Element Analysis

10.21203/rs.2.14571/v3 ◽

2020 ◽

Author(s):

Liangliang Cao ◽

Yumei Liu ◽

Wei Mei ◽

Jian-guang Xu ◽

Shi Zhan

Keyword(s):

Lumbar Spine ◽

Intervertebral Disc ◽

Nucleus Pulposus ◽

Adjacent Segment ◽

Fusion Model ◽

Fusion Surgery ◽

Flexion Extension ◽

Spine Mobility ◽

Health Model ◽

Topping Off

Abstract Background : Previous studies have revealed positive effect of Topping-off technique on upper adjacent segment after fusion surgery, while for the cases with fusion surgery on L5-S1 segment, owning maximal range of motion, and preexisting degenerated upper adjacent disc, it is necessary to clarify the superiority of Topping-ff technique and the effect exerted on the lumbar spine. Methods: A young healthy male volunteer was selected for thin-slice CT scanning. Then the image information was imported into the computer to establish the whole lumbar spine model as the health model. The medium degeneration model of intervertebral disc was established by changing the material properties of L4-S1 disc on the basis of the health model, and the fusion model and Topping-off model were respectively established on the basis of the degenerated model. The variation trend of ROM of L2-L5 and the stress changes of L4-L5 intervertebral disc, nucleus pulposus and facet joints were calculated respectively. Results: The L4-L5 ROM of fusion model increased significantly but the ROM of L2-L3 and L3-L4 segments did not change significantly. Compared with the degenerated model, L4-L5 activity of the Topping-off model decreased, and ROM of the L2-L3 and L3-L4 increased to some extent in the flexion and extension positions. the stress on the disc, nucleus pulposus and facet joint of the fusion model L4-L5 increased in four positions of flexion, extension, rotation and bending compared with the degenerated model, while the fiber stress on the Topping-off model decreased significantly in all four positions. Conclusion: Topping-off technology can decrease the stress and ROM of the adjacent upper degenerated segment, and increase the ROM of other upper segments, thereby protecting the degenerated upper adjacent segments and compensating the lumbar spine mobility.

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Biomechanical Changes of Degenerated Adjacent Segment and Intact lumbar Spine after lumbosacral Topping-off surgery: A Three-dimensional Finite Element Analysis

10.21203/rs.2.14571/v2 ◽

2019 ◽

Author(s):

Liangliang Cao ◽

Yumei Liu ◽

Wei Mei ◽

Jian-guang Xu ◽

Shi Zhan

Keyword(s):

Lumbar Spine ◽

Intervertebral Disc ◽

Nucleus Pulposus ◽

Adjacent Segment ◽

Fusion Model ◽

Fusion Surgery ◽

Flexion Extension ◽

Spine Mobility ◽

Health Model ◽

Topping Off

Abstract Background : Previous studies have revealed positive effect of Topping-off technique on upper adjacent segment after fusion surgery, while for the cases with fusion surgery on L5-S1 segment, owning maximal range of motion, and preexisting degenerated upper adjacent disc, it is necessary to clarify the superiority of Topping-ff technique and the effect exerted on the lumbar spine. Methods: A young healthy male volunteer was selected for thin-slice CT scanning. Then the image information was imported into the computer to establish the whole lumbar spine model as the health model. The medium degeneration model of intervertebral disc was established by changing the material properties of L4-S1 disc on the basis of the health model, and the fusion model and Topping-off model were respectively established on the basis of the degenerated model. The variation trend of ROM of L2-L5 and the stress changes of L4-L5 intervertebral disc, nucleus pulposus and facet joints were calculated respectively. Results: The L4-L5 ROM of fusion model increased significantly but the ROM of L2-L3 and L3-L4 segments did not change significantly. Compared with the degenerated model, L4-L5 activity of the Topping-off model decreased, and ROM of the L2-L3 and L3-L4 increased to some extent in the flexion and extension positions. the stress on the disc, nucleus pulposus and facet joint of the fusion model L4-L5 increased in four positions of flexion, extension, rotation and bending compared with the degenerated model, while the fiber stress on the Topping-off model decreased significantly in all four positions. Conclusion: Topping-off technology can decrease the stress and ROM of the adjacent upper degenerated segment, and increase the ROM of other upper segments, thereby protecting the degenerated upper adjacent segments and compensating the lumbar spine mobility.

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Experimentally Validated Computational Simulation of Lumbar Spine Intervertebral Disc Puncture

Volume 2: Biomedical and Biotechnology Engineering; Nanoengineering for Medicine and Biology ◽

10.1115/imece2011-62447 ◽

2011 ◽

Author(s):

Kristen E. Lipscomb ◽

Nesrin Sarigul-Klijn

Keyword(s):

Back Pain ◽

Lumbar Spine ◽

Intervertebral Disc ◽

Nucleus Pulposus ◽

Chronic Back Pain ◽

Medical Condition ◽

Computational Simulation ◽

Element Model ◽

Before And After ◽

Spine Model

Back pain is a debilitating medical condition, often with an unclear source. Over time, back pain can affect the work and lifestyle of an individual by reducing job productivity and time spent on enjoyable activities. Discography of the intervertebral disc (IVD) is often used to diagnose pathology of the disc and determine if it may be a source for chronic back pain. It has recently been suggested that discography may lead to IVD degeneration, and has been a cause of controversy among spine care physicians. Using the results from a cadaveric experimental model, a finite element model was first validated. Then, a study was conducted to better understand the changes caused by discography on human spine mechanics. An anatomically accurate L3-L5 lumbar spine model was developed using computed tomography scans. Discography was simulated in the model as an area in the disc affected by needle puncture. The material properties in the nucleus pulposus were adjusted to match experimental data both before and after puncture. The results show that puncture of the IVD leads to increased deformation as well as increased stresses in the disc. Pressure in the nucleus pulposus found to decrease after puncture, and was calculated in the course of this study. Puncturing the IVD changes disc mechanics and may lead to progressive spine issues in the future such as disc degeneration. While discography has been the gold standard to determine if the disc was a source of back pain in patients for many years, the potential long-term degenerative effects of the procedure are only now coming into light, and must be closely examined.

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Testing of primary stability of the Activ® L intervertebral disc prosthesis in cadaver bone and comparison of the two different anchoring concepts – keel and spike anchoring

10.21203/rs.3.rs-16688/v1 ◽

2020 ◽

Author(s):

Christoph von Schulze Pellengahr ◽

Wolfram Teske ◽

Saurabh Kapoor ◽

Alexander Klein ◽

Bernd Wegener ◽

...

Keyword(s):

Lumbar Spine ◽

Intervertebral Disc ◽

Statistical Significance ◽

Primary Stability ◽

Longitudinal Axis ◽

Disc Prosthesis ◽

Mean Values ◽

Intervertebral Disc Prosthesis ◽

Flexion Extension ◽

Micro Motion

Abstract Background: High primary stability is the fundamental prerequisite for safe osseointegration of cementless intervertebral disc prosthesis. The aim of our study was to determine the primary stability of intervertebral disc prosthesis with two different anchoring concepts – keel and spike anchoring. Methods: 10 human cadaveric lumbar spine specimens with an ActivL intervertebral disc prosthesis (5 x keel anchoring, 5 x spike anchoring) were tested on a spine simulator. Under axial load, moments of flexion, extension, left and right bending and axial rotation were applied on the lumbar spine specimens through a defined three-dimensional movement program as per ISO 2631 and ISO/CD 18192-1.3 standards. Micro-motion of the implant was measured in every axis for both anchor types and compared using statistical test for significance after calculating 95% confidence intervals. Results: In the transverse axis, the keel anchoring concept showed lower mean values of micro-motion , which was statistically significant (p<0.05) compared to spike anchoring concept. In the sagittal axis, the results were again in favour of the keel anchoring, but did not reach statistical significance (p>0.05). The highest micro-motion values were observed in the longitudinal axis. Both concepts showed values around the threshold of primary stability (150 μm) with the spike concept showing lower mean values, but without a statistically significant difference.Conclusions: Both types of anchors met the criteria of primary stability. The keel anchoring shows a slight advantage compared to anchoring with spikes. Direct postoperative active mobilization doesn’t seem to compromise the primary stability of the prosthesis.

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Discography interpretation and techniques in the lumbar spine

Neurosurgical FOCUS ◽

10.3171/foc.2002.13.2.14 ◽

2002 ◽

Vol 13 (2) ◽

pp. 1-8 ◽

Cited By ~ 9

Author(s):

Frank J. Tomecek ◽

C. Scott Anthony ◽

Chris Boxell ◽

Jennifer Warren

Keyword(s):

Low Back Pain ◽

Back Pain ◽

Lumbar Spine ◽

Intervertebral Disc ◽

Nucleus Pulposus ◽

Diagnostic Test ◽

Diagnostic Tool ◽

Radiographic Evaluation ◽

Low Back

The authors provide an indepth analysis of discography, a provocative diagnostic tool to determine the origin of low-back pain. Injecting the intervertebral disc with radiopaque dye provides physicians with several useful pieces of information. First, the modality provides radiographic evaluation of the integrity of the nucleus pulposus and anular rings to determine tears or other lesions that could be creating low-back pain. Second, and very important, is its measure of disc nociception. A normal disc should not cause pain when injected; however, a disc that is physiologically compromised can mimic the pain previously experienced by a patient. The authors review the indications, technique, and interpretation of discography to allow a better understanding of when to use this diagnostic test and what to do with the results.

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Comparison of mechanical motion profiles following instrumented fusion and non-instrumented fusion at the L4-5 segment

Clinical & Investigative Medicine ◽

10.25011/cim.v32i1.5089 ◽

2009 ◽

Vol 32 (1) ◽

pp. 64 ◽

Cited By ~ 9

Author(s):

Ho-Joong Kim ◽

Seong-Hwan Moon ◽

Heoung-Jae Chun ◽

Kyoung-Tak Kang ◽

Hak-Sun Kim ◽

...

Keyword(s):

Lumbar Spine ◽

Lumbar Fusion ◽

Angular Motion ◽

Anterior Fusion ◽

Mechanical Motion ◽

Fusion Surgery ◽

Instrumented Fusion ◽

Plain Films ◽

Flexion Extension ◽

Posterior Instrumented Fusion

Purpose: To investigate the difference in motion profiles between instrumented and non-instrumented fusion of the lumbar spine.. Method: In vivo retrospective radiological analysis of dynamic (flexion-extension) lateral plain films was performed in different lumbar spine fusion types. Twenty-eight patients underwent lumbar fusion surgery at the L4/5 level. Fourteen patients underwent anterior fusion surgery without implantation, and the others underwent posterior instrumented fusion. Segmental angular motion was measured at the fused and adjacent levels using dynamic plain lateral film 2 years after operation. Results: The anterior uninstrumented fusion group showed mean 2.0° of segmental angular motion at the fused level compared with mean of 0.8° in the posterior instrumented fusion group (P < 0.05). In contrast, at the proximal adjacent level, decreased angular motion (mean 7.7°) was noted in the anterior uninstrumented fusion group compared with mean 11.6° in the posterior instrumented fusion group (P < 0.05). Conclusion: This study suggests that differing stiffness of fusion segments could cause different mechanical motion profiles at adjacent segments.

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Primary stability of the Activ L® intervertebral disc prosthesis in cadaver bone and comparison of the keel and spike anchoring concept

10.21203/rs.3.rs-16688/v2 ◽

2021 ◽

Author(s):

Christoph von Schulze Pellengahr ◽

Wolfram Teske ◽

Saurabh Kapoor ◽

Alexander Klein ◽

Bernd Wegener ◽

...

Keyword(s):

Lumbar Spine ◽

Intervertebral Disc ◽

Three Dimensional ◽

Primary Stability ◽

Longitudinal Axis ◽

Axial Rotation ◽

Disc Prosthesis ◽

Mean Values ◽

Intervertebral Disc Prosthesis ◽

Flexion Extension

Abstract Background: High primary stability is the key prerequisite for safe osseointegration of cementless intervertebral disc prosthesis. The aim of our study was to determine the primary stability of intervertebral disc prosthesis with two different anchoring concepts – keel and spike anchoring. Methods: 10 ActivL intervertebral disc prosthesis (5 x keel anchoring, 5 x spike anchoring) implanted in human cadaver lumbar spine specimens were tested in a spine movement simulator. Under axial load flexion, extension, left and right bending and axial rotation were applied on the lumbar spine specimens through a defined three-dimensional movement program as per ISO 2631 and ISO/CD 18192-1.3 standards. Micromotion of the implants covering every single movement axis were measured for both anchor types and compared using Student’s T-test for significance after calculating 95% confidence intervals. Results: In the transverse axis, the keel anchoring concept showed lower statistically significant (p<0.05) mean values of micromotion compared to spike anchoring concept. The highest micromotion values for both types were observed in the longitudinal axis. The data achieved the threshold of primary stability (150-200 μm).Conclusions: Both fixation systems fulfil the required criteria of primary stability. Independent of the selected anchorage type an immediate postoperative active mobilization doesn’t compromise the stability of the prostheses.

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Primary stability of the Activ L® intervertebral disc prosthesis in cadaver bone and comparison of the keel and spike anchoring concept

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04544-7 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Christoph von Schulze Pellengahr ◽

Wolfram Teske ◽

Saurabh Kapoor ◽

Alexander Klein ◽

Bernd Wegener ◽

...

Keyword(s):

Lumbar Spine ◽

Intervertebral Disc ◽

Three Dimensional ◽

Primary Stability ◽

Longitudinal Axis ◽

Axial Rotation ◽

Mean Values ◽

Flexion Extension ◽

Student’S T ◽

The Stability

Abstract Background High primary stability is the key prerequisite for safe osseointegration of cementless intervertebral disc prostheses. The aim of our study was to determine the primary stability of intervertebral disc prostheses with two different anchoring concepts – keel and spike anchoring. Methods Ten ActivL intervertebral disc prostheses (5 x keel anchoring, 5 x spike anchoring) implanted in human cadaver lumbar spine specimens were tested in a spine movement simulator. Axial load flexion, extension, left and right bending and axial rotation motions were applied on the lumbar spine specimens through a defined three-dimensional movement program following ISO 2631 and ISO/CD 18192-1.3 standards. Tri-dimensional micromotions of the implants were measured for both anchor types and compared using Student’s T-test for significance after calculating 95 % confidence intervals. Results In the transverse axis, the keel anchoring concept showed statistically significant (p < 0.05) lower mean values of micromotions compared to the spike anchoring concept. The highest micromotion values for both types were observed in the longitudinal axis. In no case the threshold of 200 micrometers was exceeded. Conclusions Both fixation systems fulfill the required criteria of primary stability. Independent of the selected anchorage type an immediate postoperative active mobilization doesn’t compromise the stability of the prostheses.

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Mechanical Effectiveness of Polyvinyl Alcohol/Polyvinyl Pyrrolidone (PVA/PVP) as an Intervertebral Disc Polymer

Volume 3B: Biomedical and Biotechnology Engineering ◽

10.1115/imece2013-64767 ◽

2013 ◽

Author(s):

Kooroush Azartash-Namin ◽

Zheila Azartash-Namin ◽

S. Ashton Williams ◽

Khiet Tran ◽

M. Khandaker

Keyword(s):

Elastic Modulus ◽

Intervertebral Disc ◽

Polyvinyl Alcohol ◽

Nucleus Pulposus ◽

Low Frequency ◽

Axial Rotation ◽

Polyvinyl Pyrrolidone ◽

Disc Disease ◽

Flexion Extension ◽

Hydrogel Polymer

The intervertebral disc is one of the body’s most vital structures. It provides support and enables six degree of freedom (6DOF) motions in the spine: flexion, extension, right and left lateral bending, compression, and axial rotation. When individuals suffer from degenerative disc disease, the nucleus pulposus deteriorates, causing a loss of articulation in the intervertebral disc. To address this problem, replacements for the nucleus pulposus can be used. The objective of this study was to evaluate a potential nucleus pulposus replacement consisting of a hydrogel polymer. The hydrogel was synthesized by physically cross-linking 95%-weight polyvinyl alcohol (PVA) and 5%-weight polyvinyl pyrrolidone (PVP). PVA and PVP were selected for the hydrogel implant due to the natural biocompatibility when the two are physically cross-linked. In order to evaluate the mechanical effectiveness of the hydrogel, a slider-crank mechanism was designed and constructed to create the 6DOF motions when interfaced with a Universal Mechanical Testing System. The viscoelastic properties of the polymer were obtained using a rheometer, which determined the elastic (G′) and viscous (G″) moduli of the PVA/PVP hydrogel polymer by calculating the complex shear modulus (G*) under low-frequency oscillating shear deformation. This allows for study of the viscoelastic performance of the isolated nucleus pulposus and hydrogel implant. The elastic modulus of the hydrogel was tested at parameters 5%, 10%, and 15% strain with results of 228.6 Pa, 988.8 Pa, and 1793 Pa, respectively. However, the elastic modulus tested for the natural bovine specimen at 5%, 10%, and 15% strain were 712.9 Pa, 522.1 Pa, and 363.3 Pa, respectively.

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Effect of Physiotherapy on Back Pain and Function after the L4/L5 Disc Hernia Surgery

Reabilitacijos mokslai slauga kineziterapija ergoterapija ◽

10.33607/rmske.v2i15.709 ◽

2019 ◽

Vol 2 (15) ◽

Author(s):

Eglė Štafėlaitė ◽

Saulė Sipavičienė

Keyword(s):

Low Back Pain ◽

Back Pain ◽

Lumbar Spine ◽

Physical Therapy ◽

Intervertebral Disc ◽

Functional Disability ◽

Low Back ◽

Hernia Surgery ◽

Disc Hernia ◽

Spine Mobility

Research background. A popular physiotherapy mean is spine stability exercises, but still not so many studies have been carried out about the benefts of this technique in patients after L4/L5 spinal hernia surgery during the acute period. The aim was to assess the effectiveness of spine stabilizing exercises in patients after spinal L4/L5 intervertebral disc hernia surgery for back pain and functional status. Methods. The motion of fear evaluation, using physical therapy questionnaire (TAMPA), functional disability evaluation, using Oswestry functional disability index questionnaire, pain assessment using a symptom assessment scale (SAS), lumbar spine motility measurement, using Sober test, static endurance measurement of the waist muscles. Results. After physical therapy program back pain and functional disability decreased, back and abdominal muscle endurance and lumbar spine mobility increased. Conclusions. The patients after spinal L4/L5 intervertebral disc hernia surgery low back pain decreased and functional disability increased after applied to the spine stabilization exercises.Keywords: intervertebral disc hernia, low back pain, spine stabilizing exercises.

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