1
|
Hu Y, Liu S, Yang R, Wang H. Biomechanical Analysis of a Newly Proposed Surgical Combination (MIS Screw-Rod System for Indirect Decompression+ Interspinous Fusion System for long Term Spinal Stability) in Treatment of Lumbar Degenerative Diseases. World Neurosurg 2024; 184:e809-e820. [PMID: 38364897 DOI: 10.1016/j.wneu.2024.02.061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 02/10/2024] [Indexed: 02/18/2024]
Abstract
OBJECTIVE The aim of this study is to analyze the biomechanical stability of a newly proposed surgical combination (minimally invasive surgery of screw-rod system for indirect decompression + interspinous fusion system for long term spinal stability) in treatment of lumbar degenerative diseases. METHODS The three-dimensional (3D) computed tomography (CT) image data of an adult healthy male volunteer were selected. An intact model of L4/5 was further established and validated by using Mimic and 3-matic, 3D slicer, abaqus, Python. Four surgical models were constructed. The biomechanical stability among these surgical modes was compared and analyzed using finite element analysis. RESULTS The maximum von mises on fixation system in surgical models 2 and 3 exhibited comparable values. This finding suggested that the increase in interspinous fusion did not result in a significant elevation in maximum von mises on fixation system. Compared with the third surgical model, the fourth model, which received less average von mises experienced by the screw in contact with both cancellous and cortical bone. The findings indicated that the inclusion of facet joint fusion in surgical procedures might not be necessary to increase the average von Mises stress experienced by the screw in contact with both cancellous and cortical bone. CONCLUSIONS The biomechanical stability of the newly proposed surgical combination (MIS screw-rod for indirect decompression + interspinous fusion for long term spinal stability technique) was not lower than that of the other surgical combination groups, and it might not be necessary to perform facet joint fusion during the surgery.
Collapse
Affiliation(s)
- Yunxiang Hu
- School of Graduates, Dalian Medical University, Dalian City, Liaoning Province, China; Department of Orthopedics, Dalian Municipal Central Hospital Affiliated of Dalian Medical University, Dalian City, Liaoning Province, China
| | - Sanmao Liu
- School of Graduates, Dalian Medical University, Dalian City, Liaoning Province, China; Department of Orthopedics, Dalian Municipal Central Hospital Affiliated of Dalian Medical University, Dalian City, Liaoning Province, China
| | - Rui Yang
- School of Graduates, Dalian Medical University, Dalian City, Liaoning Province, China; Department of Orthopedics, Dalian Municipal Central Hospital Affiliated of Dalian Medical University, Dalian City, Liaoning Province, China
| | - Hong Wang
- Department of Orthopedics, Dalian Municipal Central Hospital Affiliated of Dalian Medical University, Dalian City, Liaoning Province, China.
| |
Collapse
|
2
|
Doulgeris J, Lin M, Lee W, Aghayev K, Papanastassiou ID, Tsai CT, Vrionis FD. Inter-Specimen Analysis of Diverse Finite Element Models of the Lumbar Spine. Bioengineering (Basel) 2023; 11:24. [PMID: 38247901 PMCID: PMC10813462 DOI: 10.3390/bioengineering11010024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 12/09/2023] [Accepted: 12/21/2023] [Indexed: 01/23/2024] Open
Abstract
Over the past few decades, there has been a growing popularity in utilizing finite element analysis to study the spine. However, most current studies tend to use one specimen for their models. This research aimed to validate multiple finite element models by comparing them with data from in vivo experiments and other existing finite element studies. Additionally, this study sought to analyze the data based on the gender and age of the specimens. For this study, eight lumbar spine (L2-L5) finite element models were developed. These models were then subjected to finite element analysis to simulate the six fundamental motions. CT scans were obtained from a total of eight individuals, four males and four females, ranging in age from forty-four (44) to seventy-three (73) years old. The CT scans were preprocessed and used to construct finite element models that accurately emulated the motions of flexion, extension, lateral bending, and axial rotation. Preloads and moments were applied to the models to replicate physiological loading conditions. This study focused on analyzing various parameters such as vertebral rotation, facet forces, and intradiscal pressure in all loading directions. The obtained data were then compared with the results of other finite element analyses and in vivo experimental measurements found in the existing literature to ensure their validity. This study successfully validated the intervertebral rotation, intradiscal pressure, and facet force results by comparing them with previous research findings. Notably, this study concluded that gender did not have a significant impact on the results. However, the results did highlight the importance of age as a critical variable when modeling the lumbar spine.
Collapse
Affiliation(s)
- James Doulgeris
- Department of Medical Engineering, University of South Florida, Tampa, FL 33620, USA; (J.D.); (W.L.)
| | - Maohua Lin
- Department of Ocean & Mechanical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA;
| | - William Lee
- Department of Medical Engineering, University of South Florida, Tampa, FL 33620, USA; (J.D.); (W.L.)
| | - Kamran Aghayev
- Department of Neurosurgery, Esencan Hospital, Baglarcesme Mahallesi, Istanbul 34510, Turkey;
| | | | - Chi-Tay Tsai
- Department of Ocean & Mechanical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA;
| | - Frank D. Vrionis
- Department of Neurosurgery, Marcus Neuroscience Institute, Boca Raton Regional Hospital, Boca Raton, FL 33486, USA
| |
Collapse
|
3
|
Lin M, Paul R, Liao X, Doulgeris J, Menzer EL, Dhar UK, Tsai CT, Vrionis FD. A New Method to Evaluate Pressure Distribution Using a 3D-Printed C2-C3 Cervical Spine Model with an Embedded Sensor Array. SENSORS (BASEL, SWITZERLAND) 2023; 23:9547. [PMID: 38067922 PMCID: PMC10708625 DOI: 10.3390/s23239547] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 11/14/2023] [Accepted: 11/15/2023] [Indexed: 12/18/2023]
Abstract
Cervical degenerative disc diseases such as myelopathy and radiculopathy often require conventional treatments like artificial cervical disc replacement or anterior cervical discectomy and fusion (ACDF). When designing a medical device, like the stand-alone cage, there are many design inputs to consider. However, the precise biomechanics of the force between the vertebrae and implanted devices under certain conditions require further investigation. In this study, a new method was developed to evaluate the pressure between the vertebrae and implanted devices by embedding a sensor array into a 3D-printed C2-C3 cervical spine. The 3D-printed cervical spine model was subjected to a range of axial loads while under flexion, extension, bending and compression conditions. Cables were used for the application of a preload and a robotic arm was used to recreate the natural spine motions (flexion, extension, and bending). To verify and predict the total pressure between the vertebrae and the implanted devices, a 3D finite element (FE) numerical mathematical model was developed. A preload was represented by applying 22 N of force on each of the anterior tubercles for the C2 vertebra. The results of this study suggest that the sensor is useful in identifying static pressure. The pressure with the robot arm was verified from the FE results under all conditions. This study indicates that the sensor array has promising potential to reduce the trial and error with implants for various surgical procedures, including multi-level artificial cervical disk replacement and ACDF, which may help clinicians to reduce pain, suffering, and costly follow-up procedures.
Collapse
Affiliation(s)
- Maohua Lin
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA; (M.L.); (R.P.); (U.K.D.); (C.-T.T.)
| | - Rudy Paul
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA; (M.L.); (R.P.); (U.K.D.); (C.-T.T.)
| | - Xinqin Liao
- Department of Electronic Science, Xiamen University, Xiamen 361005, China;
| | - James Doulgeris
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA; (M.L.); (R.P.); (U.K.D.); (C.-T.T.)
| | - Emma Lilly Menzer
- Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Utpal Kanti Dhar
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA; (M.L.); (R.P.); (U.K.D.); (C.-T.T.)
| | - Chi-Tay Tsai
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA; (M.L.); (R.P.); (U.K.D.); (C.-T.T.)
| | - Frank D. Vrionis
- Department of Neurosurgery, Marcus Neuroscience Institute, Boca Raton Regional Hospital, Boca Raton, FL 33486, USA
| |
Collapse
|
4
|
Lin M, Paul R, Dhar UK, Doulgeris J, O’Connor TE, Tsai CT, Vrionis FD. A Review of Finite Element Modeling for Anterior Cervical Discectomy and Fusion. Asian Spine J 2023; 17:949-963. [PMID: 37408489 PMCID: PMC10622829 DOI: 10.31616/asj.2022.0295] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 11/13/2022] [Accepted: 11/14/2022] [Indexed: 07/07/2023] Open
Abstract
The cervical spine poses many complex challenges that require complex solutions. Anterior cervical discectomy and fusion (ACDF) has been one such technique often employed to address such issues. In order to address the problems with ACDF and assess the modifications that have been made to the technique over time, finite element analyses (FEA) have proven to be an effective tool. The variations of cervical spine FEA models that have been produced over the past couple of decades, particularly more recent representations of more complex geometries, have not yet been identified and characterized in any literature. Our objective was to present material property models and cervical spine models for various simulation purposes. The outlining and refinement of the FEA process will yield more reliable outcomes and provide a stable basis for the modeling protocols of the cervical spine.
Collapse
Affiliation(s)
- Maohua Lin
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL,
USA
| | - Rudy Paul
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL,
USA
| | - Utpal Kanti Dhar
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL,
USA
| | - James Doulgeris
- Department of Neurosurgery, Marcus Neuroscience Institute, Baptist Health South Florida, Boca Raton, FL,
USA
| | - Timothy E. O’Connor
- Department of Neurosurgery, Marcus Neuroscience Institute, Baptist Health South Florida, Boca Raton, FL,
USA
| | - Chi-Tay Tsai
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL,
USA
| | - Frank D. Vrionis
- Department of Neurosurgery, Marcus Neuroscience Institute, Baptist Health South Florida, Boca Raton, FL,
USA
| |
Collapse
|
5
|
Lin M, Doulgeris J, Dhar UK, O’Corner T, Papanastassiou ID, Tsai CT, Vrionis FD. Effect of graded posterior element and ligament removal on annulus stress and segmental stability in lumbar spine stenosis: a finite element analysis study. Front Bioeng Biotechnol 2023; 11:1237702. [PMID: 37790254 PMCID: PMC10543754 DOI: 10.3389/fbioe.2023.1237702] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 08/30/2023] [Indexed: 10/05/2023] Open
Abstract
The study aimed to investigate the impact of posterior element and ligament removal on the maximum von Mises stress, and maximum shear stress of the eight-layer annulus for treating stenosis at the L3-L4 and L4-L5 levels in the lumbar spine. Previous studies have indicated that laminectomy alone can result in segmental instability unless fusion is performed. However, no direct correlations have been established regarding the impact of posterior and ligament removal. To address this gap, four models were developed: Model 1 represented the intact L2-L5 model, while model 2 involved a unilateral laminotomy involving the removal of a section of the L4 inferior lamina and 50% of the ligament flavum between L4 and L5. Model 3 consisted of a complete laminectomy, which included the removal of the spinous process and lamina of L4, as well as the relevant connecting ligaments between L3-L4 and L4-L5 (ligament flavum, interspinous ligament, supraspinous ligament). In the fourth model, a complete laminectomy with 50% facetectomy was conducted. This involved the same removals as in model 3, along with a 50% removal of the inferior/superior facets of L4 and a 50% removal of the facet capsular ligaments between L3-L4 and L4-L5. The results indicated a significant change in the range of motion (ROM) at the L3-L4 and L4-L5 levels during flexion and torque situations, but no significant change during extension and bending simulation. The ROM increased by 10% from model 1 and 2 to model 3, and by 20% to model 4 during flexion simulation. The maximum shear stress and maximum von-Mises stress of the annulus and nucleus at the L3-L4 levels exhibited the greatest increase during flexion. In all eight layers of the annulus, there was an observed increase in both the maximum shear stress and maximum von-Mises stress from model 1&2 to model 3 and model 4, with the highest rate of increase noted in layers 7&8. These findings suggest that graded posterior element and ligament removal have a notable impact on stress distribution and range of motion in the lumbar spine, particularly during flexion.
Collapse
Affiliation(s)
- Maohua Lin
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL, United States
| | - James Doulgeris
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL, United States
| | - Utpal Kanti Dhar
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL, United States
| | - Timothy O’Corner
- Department of Neurosurgery, Marcus Neuroscience Institute, Boca Raton Regional Hospital, Boca Raton, FL, United States
| | | | - Chi-Tay Tsai
- Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL, United States
| | - Frank D. Vrionis
- Department of Neurosurgery, Marcus Neuroscience Institute, Boca Raton Regional Hospital, Boca Raton, FL, United States
| |
Collapse
|
6
|
Zhang X, Yang Y, Shen YW, Zhang KR, Ma LT, Ding C, Wang BY, Meng Y, Liu H. Biomechanical performance of the novel assembled uncovertebral joint fusion cage in single-level anterior cervical discectomy and fusion: A finite element analysis. Front Bioeng Biotechnol 2023; 11:931202. [PMID: 36970630 PMCID: PMC10031026 DOI: 10.3389/fbioe.2023.931202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 02/22/2023] [Indexed: 03/11/2023] Open
Abstract
Introduction: Anterior cervical discectomy and fusion (ACDF) is widely accepted as the gold standard surgical procedure for treating cervical radiculopathy and myelopathy. However, there is concern about the low fusion rate in the early period after ACDF surgery using the Zero-P fusion cage. We creatively designed an assembled uncoupled joint fusion device to improve the fusion rate and solve the implantation difficulties. This study aimed to assess the biomechanical performance of the assembled uncovertebral joint fusion cage in single-level ACDF and compare it with the Zero-P device.Methods: A three-dimensional finite element (FE) of a healthy cervical spine (C2−C7) was constructed and validated. In the one-level surgery model, either an assembled uncovertebral joint fusion cage or a zero-profile device was implanted at the C5–C6 segment of the model. A pure moment of 1.0 Nm combined with a follower load of 75 N was imposed at C2 to determine flexion, extension, lateral bending, and axial rotation. The segmental range of motion (ROM), facet contact force (FCF), maximum intradiscal pressure (IDP), and screw−bone stress were determined and compared with those of the zero-profile device.Results: The results showed that the ROMs of the fused levels in both models were nearly zero, while the motions of the unfused segments were unevenly increased. The FCF at adjacent segments in the assembled uncovertebral joint fusion cage group was less than that that of the Zero-P group. The IDP at the adjacent segments and screw–bone stress were slightly higher in the assembled uncovertebral joint fusion cage group than in those of the Zero-P group. Stress on the cage was mainly concentrated on both sides of the wings, reaching 13.4–20.4 Mpa in the assembled uncovertebral joint fusion cage group.Conclusion: The assembled uncovertebral joint fusion cage provided strong immobilization, similar to the Zero-P device. When compared with the Zero-P group, the assembled uncovertebral joint fusion cage achieved similar resultant values regarding FCF, IDP, and screw–bone stress. Moreover, the assembled uncovertebral joint fusion cage effectively achieved early bone formation and fusion, probably due to proper stress distributions in the wings of both sides.
Collapse
|