Prediction of the Cervical Spine Instability under Facet Joint Resection Extent of Foraminotomy by Using Finite Element Analysis

Prediction of the Cervical Spine Instability under Facet Joint Resection Extent of Foraminotomy by Using Finite Element Analysis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Prediction of the Cervical Spine Instability under Facet Joint Resection Extent of Foraminotomy by Using Finite Element Analysis Seungjun Ryu, Yu-Rim Oh, Ji Hyeon Kim, JI-Won Kang, Yeo-Jin Jeon, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8121405/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study aimed to quantify the biomechanical effects of varying extents of facet joint resection during cervical foraminotomy using finite element analysis (FEA), and to compare outcomes under open versus minimally invasive surgical conditions. A validated cervical spine model (C3–C6) was used to simulate unilateral foraminotomy at C4–C5 with progressive left facet joint resection from 0% to 100% in 12.5% increments. Biomechanical parameters, including range of motion (ROM), intradiscal pressure (IDP), and annular peak von Mises stress (PVMS), were analyzed to evaluate spinal stability and degeneration risk. Resection beyond 62.5% resulted in marked increases in ROM (2–18% in left lateral bending, 6–26% in right axial rotation). IDP rose by up to 23% in left lateral bending and 38% in right axial rotation at ≥ 87.5% resection, while PVMS increased sharply in right axial rotation and moderately in extension beyond 50%. These findings identify 62.5% as a critical instability threshold. While our current analysis focused on osseoligamentous structures, future work will incorporate the effects of paraspinal musculature to better reflect minimally invasive surgical conditions. Our results provide quantitative evidence to guide surgical decision-making in balancing adequate decompression with the preservation of cervical stability. Health sciences/Anatomy Health sciences/Diseases Physical sciences/Engineering Health sciences/Health care Health sciences/Medical research Cervical foraminotomy Facet joint Finite element analysis Spinal stability Minimally invasive spine surgery Biomechanics Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 INTRODUCTION Cervical spine degenerative diseases, such as cervical spondylosis and disc herniation, often necessitate surgical interventions like anterior cervical discectomy and fusion (ACDF) or posterior decompression surgeries [ 1 , 2 ]. These procedures aim to relieve nerve root compression and restore spinal stability [ 1 ]. Particularly, posterior decompression surgeries, including foraminotomy, involve resecting portions of the facet joints to alleviate pressure on the nerve roots [ 3 , 5 ]. However, the extent of facet joint resection can significantly impact spinal stability, potentially leading to post-operative [ 4 , 6 ]. Ensuring an optimal balance between adequate decompression and preservation of spinal stability remains a critical concern in spinal surgery [ 3 , 5 ]. Finite Element Method (FEM) analysis has been extensively used in spinal research to simulate and analyze the biomechanical behavior of the cervical spine under various conditions[ 7 , 8 ]. Previous studies utilizing FEM have provided valuable insights into spinal mechanics, including the effects of surgical interventions [ 11 ]. For example, previous studies have examined how spinal elements share loads [ 3 , 4 ], and have investigated the role of facet joints in bearing loads in the lumbar spine. Similarly, studies like those have contributed to understanding the mechanical behavior of the cervical spine [ 5 , 6 ] and the impacts of different surgical techniques [ 9 ]. However, while FEM studies are abundant in the lumbar region, similar biomechanical analyses for the cervical spine remain relatively scarce. This gap in the literature highlights the need for cervical-specific FEM models that can accurately reflect the anatomical and mechanical characteristics of the cervical spine, especially under minimally invasive surgical conditions. Despite these advancements, specific quantitative data on how varying extents of facet joint resection affect spinal stability and load distribution remain limited [ 7 , 8 ]. With the increasing adoption of endoscopic spine surgery and minimally invasive spine surgery, research on the extent of facet resection in posterior cervical surgery varies depending on the spine surgeon's experience and patient’s condition [ 12 , 13 ]. Therefore, this study aims to address these gaps by employing finite element analysis to simulate various degrees of facet joint resection and predict the resulting stability of the cervical spine. By providing detailed quantitative data on the relationship between resection extent of cervical facet and spinal instability, this research seeks to establish guidelines for optimal posterior cervical facetectomy techniques with the biomechanical effects of varying degrees of facet joint resection. MATERIALS AND METHODS This study was based on finite element modeling using previously acquired, de-identified cervical spine CT images and did not involve any direct patient contact or intervention. The study protocol was reviewed and approved by the Institutional Review Board of Severance Hospital, Yonsei University College of Medicine (IRB No. 2024-1655-004). All methods were carried out in accordance with the Declaration of Helsinki and relevant institutional guidelines and regulations. As all CT images had been obtained earlier for routine clinical care and were fully anonymized prior to analysis, the Institutional Review Board waived the requirement for obtaining additional written informed consent from individual patients and approved their use for research purposes. The finite element model of the cervical spine (C3-C6) was developed based on de-identified computed tomography (CT) images of a healthy 26-year-old male (70 kg) with no history of cervical spine disease or radiological abnormalities. This model, validated in previous research, served as the foundation for biomechanical analysis[ 14 ]. To briefly explain the construction method, the CT image was constructed using the software Mimics 19 (Materialise, Inc., Belgium), and was reconstructed by processing the mesh through the software ABAQUS (V 6.91, Dassault Systèmes, France). To simulate the surgical procedure, a unilateral foraminotomy model was developed at the C4-C5 segment using the finite element model. Facet joint resection was progressively increased from 0% to 100% in 12.5% increments, resulting in a total of 9 models. (Fig. 1 ) Facet joint resection was performed from the medial side of the left facet toward the foramen, using the posterior view as a reference. The height of the resection was defined from pedicle to pedicle. Foraminotomy models included laminotomy to reflect the real surgical procedure. (Fig. 2 ) Table 1 summarizes the material properties applied to the finite element model of the cervical spine. The properties were approved with reference to previous studies. The model components include various osseous and soft tissue structures, each assigned specific values for Young’s modulus, Poisson’s ratio, and cross-sectional area (for ligaments). The properties were derived from previously published biomechanical studies to accurately represent the mechanical behavior of cervical spinal tissues. Table 1 Material properties of FEA model Component Young's Modulus Poisson's Ratio Cross-section area Cortical 12000 0.29 - Cancellous 450 0.29 - Posterior element 3500 0.29 - Endplate 500 0.4 - articular facet 10.4 0.45 - Annulus matrix 3.4 0.04 - Annulus fibers 110 0.45 - Nucleus pulposus 1 0.499 - LF 1.5 0.3 1.6 PLL 10 0.3 1.08 SSL 1.5 0.3 2.5 ALL 30 0.4 1.22 ISL 1.5 0.3 2 Abbreviations: LF: Ligamentum Flavum PLL: Posterior Longitudinal Ligament SSL: Supraspinous Ligament ALL: Anterior Longitudinal Ligament ISL: Interspinous Ligament Frictionless surface to surface contact conditions were applied between each facet joint of the model. Intact cervical model was applied with a follower load of 73.6 N to maintain the spinal structure[ 15 ]. In addition, a pure moment of 1 NM was applied to all models to implement six movements of the spine, and the inferior endplate of C6 was fixed against movement in all directions. (Fig. 3 ) The biomechanical analysis focused on three key parameters to assess post-foraminotomy stability, as illustrated in Fig. 4 . The ROM was measured as the angular displacement between C4 and C5 vertebrae under each loading condition, providing quantitative data on segmental mobility changes (Fig. 4 A). The IDP was calculated at the center of the C4-C5 intervertebral disc, with pressure distribution visualized through color-coded contour maps to identify areas of increased mechanical stress (Fig. 4 B). The PVMS analysis on the annulus fibrosus was performed to detect regions of maximum stress concentration, displayed as color gradients ranging from blue (minimum stress) to red (maximum stress), which helped predict potential sites of disc degeneration (Fig. 4 C). All other conditions were kept the same to reflect the biomechanical conditions after foraminotomy. These three parameters—ROM, IDP, and PVMS—served as indicators for evaluating post-surgical stability. Specifically, increased ROM values indicated potential spinal instability, while elevated IDP and PVMS measurements were used as predictors for accelerated disc degeneration risk. These results allowed for the evaluation of cervical spine instability based on the extent of facet joint resection during foraminotomy. RESULTS The ROM analysis was derived by measuring the angle before and after load application. As the extent of foraminotomy increased, there was a tendency for ROM to increase. Since the model was left-side incision, significant differences were observed in LLB and RAR. Compared to the intact model, the LLB surgical model showed an increase of approximately 16–18% in over 87.5% of cases, and the RAR surgical model showed an increase of 6–26% in over 62.5% of cases. This indicates that excessive mobility appears when more than 62.5% is resected. Because excessive mobility can lead to disc degeneration, IDP and Annulus PVMS were also analyzed. IDP results showed a similar trend to ROM, increasing with the extent of resection. Compared to the intact model, surgical models with more than 87.5% resection showed a 23–27% increase in LLB and a sharp 38–41% increase in RAR. This suggests greater vulnerability to rotational movement than to bending, which is also evident in the contour plots in Fig. 5 . The pressure distribution patterns visualized in Fig. 6 clearly illustrate the concentration of stress at the left lateral aspect of the nucleus pulposus during left lateral bending, with the intensity increasing proportionally with the extent of resection. Additionally, since a portion of the lamina was removed when constructing the surgical models, models with more than 25% resection in FX showed a 4–6% increase. An increase in IDP can compromise the load-bearing function of the nucleus pulposus and is therefore an important indicator of disc degeneration. Annulus PVMS also showed a similar pattern. In LLB, it differed from the intact model by up to 7–8%, whereas in models with more than 87.5% resection. In RAR, it showed a sharp difference of 11–39% with more than 62.5% resection. This suggests that both LLB and RAR movements induce spinal instability, with RAR likely causing greater instability. Moreover, in FX, models with more than 25% resection showed a 9–12% increase compared to the intact model. These results indicate that as the extent of resection increases, the risk of annular degeneration and damage also increases. Overall, the results suggest that in models with over 62.5% resection, not only does cervical mobility increase, but biomechanical instability of the cervical spine also worsens due to disc degeneration. DISCUSSION The FEM analysis reveals significant biomechanical impacts of varying degrees of facet joint resection on cervical spine stability. The key findings indicate that while flexion and extension show stable ROM across all resection types, surgical facetectomy site, such as left lateral bending exhibits significant increases in ROM with higher resection extents. This suggests increased instability in left lateral bending as more of the facet joint is resected. Intradiscal Pressure (IDP) analysis shows that IDP remains stable in flexion and extension across all resection types. However, significant increases are observed in left lateral bending. This rise in disc pressure during lateral bending highlights the potential risk of disc herniation with extensive resection. Annulus Peak von Mises Stress (PVMS) results indicate that PVMS remains stable in flexion and extension across all resection types. Significant increases are observed in left lateral bending also, indicating heightened stress on the annulus fibrosus and potential for annular damage. In our FE models, load-sharing metrics (IDP, PVMS) rose dose-dependently with resection—most prominently in axial rotation—such that ≥ 87.5% resection increased LLB by 23–27% and RAR by 38–41%, while even ≥ 25% resection elevated FX (IDP + 4–6%), collectively indicating that posterior element loss preferentially destabilizes rotation over bending and, via heightened disc pressures/stresses, plausibly accelerates annular degeneration; accordingly, beyond ~ 62.5% resection the cervical segment exhibits not only greater ROM but a transition toward biomechanical instability consistent with prior reports linking facetectomy/laminectomy to increased annular stress and rotational laxity. These results indicate that even under minimal invasive spine surgery or endoscopic surgery, excessive resection still leads to biomechanical stress elevation, particularly in bending and rotational movements, and emphasize the importance of minimizing facet joint resection. While resection up to 50% appears to preserve relative spinal stability, exceeding 62.5% is associated with marked increases in ROM, IDP, and PVMS—especially in LLB and RAR directions. These results define a biomechanical threshold, beyond which the risk of instability and annular stress becomes clinically significant. Therefore, careful intraoperative judgment is essential to balance decompression and stability. Because minimally invasive spine (MIS) or endoscopic surgery has been suggested to mitigate destabilizing effects by preserving paraspinal musculature and posterior ligamentous structures, we hypothesize that in MIS or endoscopic approaches, preserved musculature may redistribute loads away from the skeletal elements, thereby allowing a slightly greater extent of resection without compromising stability under our findings. To test this hypothesis, future work will incorporate musculature into the finite element model to more accurately evaluate the biomechanical advantages of muscle-preserving surgical techniques. Previous studies have extensively used FEM to simulate and analyze the biomechanical behavior of the cervical and lumbar spine under various conditions [ 3 , 9 , 17 ], but did not specifically address the detailed impact of varying degrees of facet joint resection. This study builds on these foundational works by focusing specifically on the effects of different resection extents during cervical foraminotomy. By providing detailed quantitative data on ROM, IDP, and PVMS, this study offers a more focused analysis of the biomechanical consequences of facet joint resection. Additionally, it provides evidence-based insight into how facet resection impacts cervical stability in the context of muscle-preserving, MIS or endoscopic cervical spine procedures, which are becoming increasingly common in clinical practice. Despite the valuable insights provided by this study, several limitations should be discussed. First, the FEM model used, while highly detailed, may not fully capture the complex biomechanical interactions in the cervical spine. Real-world variations in patient anatomy and surgical techniques could lead to different outcomes. Second, the study focuses on immediate biomechanical impacts and does not account for long-term changes or degeneration that may occur following surgery. Longitudinal studies and clinical trials are needed to validate these findings and assess the long-term implications of different resection extents in posterior cervical surgery, and further validation through clinical outcomes and intraoperative load measurements is necessary to confirm the mechanical advantages suggested by the FEM model. CONCLUSION This study provides detailed quantitative data on the biomechanical impacts of varying degrees of facet joint resection on cervical spine stability. Resection of up to 50% of the facet joint preserved overall spinal stability, with minimal changes in range of motion (ROM), intradiscal pressure (IDP), and annular peak von Mises stress (PVMS). However, as the extent of resection increased, particularly beyond 62.5%, a marked increase in ROM and PVMS was observed, especially in lateral bending and axial rotation. Our findings suggest that mechanical stability begins to deteriorate beyond this threshold. To develop comprehensive guidelines for extensive cervical foraminotomy, further clinical validation will be needed. Declarations Conflict of Interest: The authors have nothing to disclose. Research Ethics: This study was based on finite element modeling and did not involve human participants or animals. Therefore, approval by an Institutional Review Board (IRB) or Animal Ethics Committee was not required. Author Contribution Conceptualization: Y.-R. Oh, S. Ryu, D.-A. Shin, S.-J. Lee, and C. K. Lee; data curation: J.-W. Kang, Y.-J. Jeon, J.H.Kim, N. D. Nguyen, and S. Ryu; formal analysis: S. Ryu, J.-W. Kang, and N. D. Nguyen; funding acquisition: S.-J. Lee, C. K. Lee; methodology: Y.-R. Oh, S. Ryu, D.-A. Shin, and C. K. Lee; project administration: S.-J. Lee and Y.-J. Jeon; visualization: Y.-R. Oh, J.-W. Kang, N. D. Nguyen, and S. Ryu; writing—original draft: Y.-R. Oh, S. Ryu, J.-W.; writing—review and editing: Y.-R. Oh, S. Ryu, S.-J. Lee, and C. K. Lee; supervision: S.-J. Lee and C. K. Lee Acknowledgement This study was supported by a MEF Fellowship conducted as part of the 'Education and Research Capacity Building Project at the University of Medicine and Pharmacy at Ho Chi Minh City,' funded by the Korea International Cooperation Agency (KOICA) during 2021-2026. (No. 2021-00020-4). Additionally, This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government (RS-20023-00233632). Data Availability The data supporting this study's findings are not openly available due to reasons of sensitivity and are available from the corresponding author upon reasonable request. References Decker, R. C. Surgical treatment and outcomes of cervical radiculopathy. Phys. 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Posterior cervical inclinatory foraminotomy for spondylotic radiculopathy: preliminary. J. Korean Neurosurg. Soc. 49 , 308–313 (2011). Additional Declarations No competing interests reported. Supplementary Files Result1ROM.pdf Result2IDP.pdf Result3PVMS.pdf Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8121405","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":556617261,"identity":"4a574add-718a-4042-a9ec-66e9174ded0d","order_by":0,"name":"Seungjun Ryu","email":"","orcid":"","institution":"Eulji School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Seungjun","middleName":"","lastName":"Ryu","suffix":""},{"id":556617262,"identity":"7e31fd06-460b-46a6-9cb7-544a9181a117","order_by":1,"name":"Yu-Rim Oh","email":"","orcid":"","institution":"Inje 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15:23:31","extension":"pdf","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":36822,"visible":true,"origin":"","legend":"","description":"","filename":"Result3PVMS.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8121405/v1/1545e886e87eab33b784c6d3.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Prediction of the Cervical Spine Instability under Facet Joint Resection Extent of Foraminotomy by Using Finite Element Analysis","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eCervical spine degenerative diseases, such as cervical spondylosis and disc herniation, often necessitate surgical interventions like anterior cervical discectomy and fusion (ACDF) or posterior decompression surgeries [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. These procedures aim to relieve nerve root compression and restore spinal stability [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Particularly, posterior decompression surgeries, including foraminotomy, involve resecting portions of the facet joints to alleviate pressure on the nerve roots [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. However, the extent of facet joint resection can significantly impact spinal stability, potentially leading to post-operative [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Ensuring an optimal balance between adequate decompression and preservation of spinal stability remains a critical concern in spinal surgery [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eFinite Element Method (FEM) analysis has been extensively used in spinal research to simulate and analyze the biomechanical behavior of the cervical spine under various conditions[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Previous studies utilizing FEM have provided valuable insights into spinal mechanics, including the effects of surgical interventions [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. For example, previous studies have examined how spinal elements share loads [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e], and have investigated the role of facet joints in bearing loads in the lumbar spine. Similarly, studies like those have contributed to understanding the mechanical behavior of the cervical spine [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] and the impacts of different surgical techniques [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eHowever, while FEM studies are abundant in the lumbar region, similar biomechanical analyses for the cervical spine remain relatively scarce. This gap in the literature highlights the need for cervical-specific FEM models that can accurately reflect the anatomical and mechanical characteristics of the cervical spine, especially under minimally invasive surgical conditions.\u003c/p\u003e\u003cp\u003eDespite these advancements, specific quantitative data on how varying extents of facet joint resection affect spinal stability and load distribution remain limited [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eWith the increasing adoption of endoscopic spine surgery and minimally invasive spine surgery, research on the extent of facet resection in posterior cervical surgery varies depending on the spine surgeon's experience and patient\u0026rsquo;s condition [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eTherefore, this study aims to address these gaps by employing finite element analysis to simulate various degrees of facet joint resection and predict the resulting stability of the cervical spine. By providing detailed quantitative data on the relationship between resection extent of cervical facet and spinal instability, this research seeks to establish guidelines for optimal posterior cervical facetectomy techniques with the biomechanical effects of varying degrees of facet joint resection.\u003c/p\u003e"},{"header":"MATERIALS AND METHODS","content":"\u003cp\u003eThis study was based on finite element modeling using previously acquired, de-identified cervical spine CT images and did not involve any direct patient contact or intervention. The study protocol was reviewed and approved by the Institutional Review Board of Severance Hospital, Yonsei University College of Medicine (IRB No. 2024-1655-004). All methods were carried out in accordance with the Declaration of Helsinki and relevant institutional guidelines and regulations. As all CT images had been obtained earlier for routine clinical care and were fully anonymized prior to analysis, the Institutional Review Board waived the requirement for obtaining additional written informed consent from individual patients and approved their use for research purposes. The finite element model of the cervical spine (C3-C6) was developed based on de-identified computed tomography (CT) images of a healthy 26-year-old male (70 kg) with no history of cervical spine disease or radiological abnormalities. This model, validated in previous research, served as the foundation for biomechanical analysis[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. To briefly explain the construction method, the CT image was constructed using the software Mimics 19 (Materialise, Inc., Belgium), and was reconstructed by processing the mesh through the software ABAQUS (V 6.91, Dassault Syst\u0026egrave;mes, France).\u003c/p\u003e\u003cp\u003eTo simulate the surgical procedure, a unilateral foraminotomy model was developed at the C4-C5 segment using the finite element model. Facet joint resection was progressively increased from 0% to 100% in 12.5% increments, resulting in a total of 9 models. (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) Facet joint resection was performed from the medial side of the left facet toward the foramen, using the posterior view as a reference. The height of the resection was defined from pedicle to pedicle. Foraminotomy models included laminotomy to reflect the real surgical procedure. (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e summarizes the material properties applied to the finite element model of the cervical spine. The properties were approved with reference to previous studies. The model components include various osseous and soft tissue structures, each assigned specific values for Young\u0026rsquo;s modulus, Poisson\u0026rsquo;s ratio, and cross-sectional area (for ligaments). The properties were derived from previously published biomechanical studies to accurately represent the mechanical behavior of cervical spinal tissues.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eMaterial properties of FEA model\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eComponent\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eYoung's Modulus\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePoisson's Ratio\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eCross-section area\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCortical\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e12000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCancellous\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e450\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePosterior element\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3500\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEndplate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e500\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003earticular facet\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAnnulus matrix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAnnulus fibers\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e110\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNucleus pulposus\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.499\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLF\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePLL\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.08\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSSL\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eALL\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.22\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eISL\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e\u003cp\u003eAbbreviations: LF: Ligamentum Flavum PLL: Posterior Longitudinal Ligament SSL: Supraspinous Ligament ALL: Anterior Longitudinal Ligament ISL: Interspinous Ligament\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eFrictionless surface to surface contact conditions were applied between each facet joint of the model. Intact cervical model was applied with a follower load of 73.6 N to maintain the spinal structure[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. In addition, a pure moment of 1 NM was applied to all models to implement six movements of the spine, and the inferior endplate of C6 was fixed against movement in all directions. (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe biomechanical analysis focused on three key parameters to assess post-foraminotomy stability, as illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. The ROM was measured as the angular displacement between C4 and C5 vertebrae under each loading condition, providing quantitative data on segmental mobility changes (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA). The IDP was calculated at the center of the C4-C5 intervertebral disc, with pressure distribution visualized through color-coded contour maps to identify areas of increased mechanical stress (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB). The PVMS analysis on the annulus fibrosus was performed to detect regions of maximum stress concentration, displayed as color gradients ranging from blue (minimum stress) to red (maximum stress), which helped predict potential sites of disc degeneration (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eC).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eAll other conditions were kept the same to reflect the biomechanical conditions after foraminotomy. These three parameters\u0026mdash;ROM, IDP, and PVMS\u0026mdash;served as indicators for evaluating post-surgical stability. Specifically, increased ROM values indicated potential spinal instability, while elevated IDP and PVMS measurements were used as predictors for accelerated disc degeneration risk. These results allowed for the evaluation of cervical spine instability based on the extent of facet joint resection during foraminotomy.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003eThe ROM analysis was derived by measuring the angle before and after load application. As the extent of foraminotomy increased, there was a tendency for ROM to increase. Since the model was left-side incision, significant differences were observed in LLB and RAR. Compared to the intact model, the LLB surgical model showed an increase of approximately 16\u0026ndash;18% in over 87.5% of cases, and the RAR surgical model showed an increase of 6\u0026ndash;26% in over 62.5% of cases. This indicates that excessive mobility appears when more than 62.5% is resected. Because excessive mobility can lead to disc degeneration, IDP and Annulus PVMS were also analyzed.\u003c/p\u003e\u003cp\u003eIDP results showed a similar trend to ROM, increasing with the extent of resection. Compared to the intact model, surgical models with more than 87.5% resection showed a 23\u0026ndash;27% increase in LLB and a sharp 38\u0026ndash;41% increase in RAR. This suggests greater vulnerability to rotational movement than to bending, which is also evident in the contour plots in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. The pressure distribution patterns visualized in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e clearly illustrate the concentration of stress at the left lateral aspect of the nucleus pulposus during left lateral bending, with the intensity increasing proportionally with the extent of resection. Additionally, since a portion of the lamina was removed when constructing the surgical models, models with more than 25% resection in FX showed a 4\u0026ndash;6% increase. An increase in IDP can compromise the load-bearing function of the nucleus pulposus and is therefore an important indicator of disc degeneration.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eAnnulus PVMS also showed a similar pattern. In LLB, it differed from the intact model by up to 7\u0026ndash;8%, whereas in models with more than 87.5% resection. In RAR, it showed a sharp difference of 11\u0026ndash;39% with more than 62.5% resection. This suggests that both LLB and RAR movements induce spinal instability, with RAR likely causing greater instability. Moreover, in FX, models with more than 25% resection showed a 9\u0026ndash;12% increase compared to the intact model. These results indicate that as the extent of resection increases, the risk of annular degeneration and damage also increases. Overall, the results suggest that in models with over 62.5% resection, not only does cervical mobility increase, but biomechanical instability of the cervical spine also worsens due to disc degeneration.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThe FEM analysis reveals significant biomechanical impacts of varying degrees of facet joint resection on cervical spine stability. The key findings indicate that while flexion and extension show stable ROM across all resection types, surgical facetectomy site, such as left lateral bending exhibits significant increases in ROM with higher resection extents. This suggests increased instability in left lateral bending as more of the facet joint is resected.\u003c/p\u003e\u003cp\u003eIntradiscal Pressure (IDP) analysis shows that IDP remains stable in flexion and extension across all resection types. However, significant increases are observed in left lateral bending. This rise in disc pressure during lateral bending highlights the potential risk of disc herniation with extensive resection. Annulus Peak von Mises Stress (PVMS) results indicate that PVMS remains stable in flexion and extension across all resection types. Significant increases are observed in left lateral bending also, indicating heightened stress on the annulus fibrosus and potential for annular damage.\u003c/p\u003e\u003cp\u003eIn our FE models, load-sharing metrics (IDP, PVMS) rose dose-dependently with resection\u0026mdash;most prominently in axial rotation\u0026mdash;such that \u0026ge;\u0026thinsp;87.5% resection increased LLB by 23\u0026ndash;27% and RAR by 38\u0026ndash;41%, while even \u0026ge;\u0026thinsp;25% resection elevated FX (IDP\u0026thinsp;+\u0026thinsp;4\u0026ndash;6%), collectively indicating that posterior element loss preferentially destabilizes rotation over bending and, via heightened disc pressures/stresses, plausibly accelerates annular degeneration; accordingly, beyond ~\u0026thinsp;62.5% resection the cervical segment exhibits not only greater ROM but a transition toward biomechanical instability consistent with prior reports linking facetectomy/laminectomy to increased annular stress and rotational laxity.\u003c/p\u003e\u003cp\u003eThese results indicate that even under minimal invasive spine surgery or endoscopic surgery, excessive resection still leads to biomechanical stress elevation, particularly in bending and rotational movements, and emphasize the importance of minimizing facet joint resection. While resection up to 50% appears to preserve relative spinal stability, exceeding 62.5% is associated with marked increases in ROM, IDP, and PVMS\u0026mdash;especially in LLB and RAR directions. These results define a biomechanical threshold, beyond which the risk of instability and annular stress becomes clinically significant. Therefore, careful intraoperative judgment is essential to balance decompression and stability.\u003c/p\u003e\u003cp\u003eBecause minimally invasive spine (MIS) or endoscopic surgery has been suggested to mitigate destabilizing effects by preserving paraspinal musculature and posterior ligamentous structures, we hypothesize that in MIS or endoscopic approaches, preserved musculature may redistribute loads away from the skeletal elements, thereby allowing a slightly greater extent of resection without compromising stability under our findings. To test this hypothesis, future work will incorporate musculature into the finite element model to more accurately evaluate the biomechanical advantages of muscle-preserving surgical techniques.\u003c/p\u003e\u003cp\u003ePrevious studies have extensively used FEM to simulate and analyze the biomechanical behavior of the cervical and lumbar spine under various conditions [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], but did not specifically address the detailed impact of varying degrees of facet joint resection.\u003c/p\u003e\u003cp\u003eThis study builds on these foundational works by focusing specifically on the effects of different resection extents during cervical foraminotomy. By providing detailed quantitative data on ROM, IDP, and PVMS, this study offers a more focused analysis of the biomechanical consequences of facet joint resection. Additionally, it provides evidence-based insight into how facet resection impacts cervical stability in the context of muscle-preserving, MIS or endoscopic cervical spine procedures, which are becoming increasingly common in clinical practice.\u003c/p\u003e\u003cp\u003eDespite the valuable insights provided by this study, several limitations should be discussed. First, the FEM model used, while highly detailed, may not fully capture the complex biomechanical interactions in the cervical spine. Real-world variations in patient anatomy and surgical techniques could lead to different outcomes. Second, the study focuses on immediate biomechanical impacts and does not account for long-term changes or degeneration that may occur following surgery. Longitudinal studies and clinical trials are needed to validate these findings and assess the long-term implications of different resection extents in posterior cervical surgery, and further validation through clinical outcomes and intraoperative load measurements is necessary to confirm the mechanical advantages suggested by the FEM model.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eThis study provides detailed quantitative data on the biomechanical impacts of varying degrees of facet joint resection on cervical spine stability. Resection of up to 50% of the facet joint preserved overall spinal stability, with minimal changes in range of motion (ROM), intradiscal pressure (IDP), and annular peak von Mises stress (PVMS). However, as the extent of resection increased, particularly beyond 62.5%, a marked increase in ROM and PVMS was observed, especially in lateral bending and axial rotation. Our findings suggest that mechanical stability begins to deteriorate beyond this threshold. To develop comprehensive guidelines for extensive cervical foraminotomy, further clinical validation will be needed.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003ch2\u003eConflict of Interest:\u003c/h2\u003e\u003cp\u003eThe authors have nothing to disclose.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003ch2\u003eResearch Ethics:\u003c/h2\u003e\u003cp\u003eThis study was based on finite element modeling and did not involve human participants or animals. Therefore, approval by an Institutional Review Board (IRB) or Animal Ethics Committee was not required.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eConceptualization: Y.-R. Oh, S. Ryu, D.-A. Shin, S.-J. Lee, and C. K. Lee; data curation: J.-W. Kang, Y.-J. Jeon, J.H.Kim, N. D. Nguyen, and S. Ryu; formal analysis: S. Ryu, J.-W. Kang, and N. D. Nguyen; funding acquisition: S.-J. Lee, C. K. Lee; methodology: Y.-R. Oh, S. Ryu, D.-A. Shin, and C. K. Lee; project administration: S.-J. Lee and Y.-J. Jeon; visualization: Y.-R. Oh, J.-W. Kang, N. D. Nguyen, and S. Ryu; writing\u0026mdash;original draft: Y.-R. Oh, S. Ryu, J.-W.; writing\u0026mdash;review and editing: Y.-R. Oh, S. Ryu, S.-J. Lee, and C. K. Lee; supervision: S.-J. Lee and C. K. Lee\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eThis study was supported by a MEF Fellowship conducted as part of the 'Education and Research Capacity Building Project at the University of Medicine and Pharmacy at Ho Chi Minh City,' funded by the Korea International Cooperation Agency (KOICA) during 2021-2026. (No. 2021-00020-4). Additionally, This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government (RS-20023-00233632).\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe data supporting this study's findings are not openly available due to reasons of sensitivity and are available from the corresponding author upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDecker, R. C. Surgical treatment and outcomes of cervical radiculopathy. \u003cem\u003ePhys. Med. Rehabil. Clin. North Am.\u003c/em\u003e \u003cb\u003e22\u003c/b\u003e, 179\u0026ndash;191 (2011).\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFriedenberg, Z. B. \u0026amp; Miller, W. T. 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Finite element analysis of the cervical spine: a material property sensitivity study. \u003cem\u003eClin. Biomech. (Bristol Avon)\u003c/em\u003e. \u003cb\u003e14\u003c/b\u003e (1), 41\u0026ndash;53 (1999).\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChang, J. C., Park, H. K. \u0026amp; Choi, S. K. Posterior cervical inclinatory foraminotomy for spondylotic radiculopathy: preliminary. \u003cem\u003eJ. Korean Neurosurg. Soc.\u003c/em\u003e \u003cb\u003e49\u003c/b\u003e, 308\u0026ndash;313 (2011).\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Cervical foraminotomy, Facet joint, Finite element analysis, Spinal stability, Minimally invasive spine surgery, Biomechanics","lastPublishedDoi":"10.21203/rs.3.rs-8121405/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8121405/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study aimed to quantify the biomechanical effects of varying extents of facet joint resection during cervical foraminotomy using finite element analysis (FEA), and to compare outcomes under open versus minimally invasive surgical conditions. A validated cervical spine model (C3\u0026ndash;C6) was used to simulate unilateral foraminotomy at C4\u0026ndash;C5 with progressive left facet joint resection from 0% to 100% in 12.5% increments. Biomechanical parameters, including range of motion (ROM), intradiscal pressure (IDP), and annular peak von Mises stress (PVMS), were analyzed to evaluate spinal stability and degeneration risk. Resection beyond 62.5% resulted in marked increases in ROM (2\u0026ndash;18% in left lateral bending, 6\u0026ndash;26% in right axial rotation). IDP rose by up to 23% in left lateral bending and 38% in right axial rotation at \u0026ge;\u0026thinsp;87.5% resection, while PVMS increased sharply in right axial rotation and moderately in extension beyond 50%. These findings identify 62.5% as a critical instability threshold. While our current analysis focused on osseoligamentous structures, future work will incorporate the effects of paraspinal musculature to better reflect minimally invasive surgical conditions. Our results provide quantitative evidence to guide surgical decision-making in balancing adequate decompression with the preservation of cervical stability.\u003c/p\u003e","manuscriptTitle":"Prediction of the Cervical Spine Instability under Facet Joint Resection Extent of Foraminotomy by Using Finite Element Analysis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-08 12:37:05","doi":"10.21203/rs.3.rs-8121405/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"bd05f0a9-f9a7-4ae5-a28e-ea3e89b25fe0","owner":[],"postedDate":"December 8th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":59236057,"name":"Health sciences/Anatomy"},{"id":59236058,"name":"Health sciences/Diseases"},{"id":59236059,"name":"Physical sciences/Engineering"},{"id":59236060,"name":"Health sciences/Health care"},{"id":59236061,"name":"Health sciences/Medical research"}],"tags":[],"updatedAt":"2025-12-16T03:09:13+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-08 12:37:05","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8121405","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8121405","identity":"rs-8121405","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}