Effect of Graded Facetectomy on Lumbar Biomechanics

Zeng, Zhili; Zhu, Rui; Yangchun, Wu; Zuo, Wei; Yu, Yan; Wang, Jianjie; Cheng, Liming

doi:10.1155/2017/7981513

Cited by 36 publications

(36 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A review of recent studies shows that on average, lumbar spine FEMs from L1-L5 based on CT scans contain approximately 140 000 nodes. 9,11,12,32,[43][44][45][46][47][48] To make a comparison of the computation time required by these models to the time required by the CEM presented in this article, the mesh for the CEM was refined to approximately 140 000 nodes, and a pure moment was applied. When the 140 000-node mesh was used, the model took more than 6 times as long to converge on a solution when compared to the case where 35 000 nodes were used (the standard number of nodes used for the studies presented in this article).…”

Section: Advantages Of a Simplified Cemmentioning

confidence: 99%

Development and Validation of a Computationally Efficient Finite Element Model of the Human Lumbar Spine: Application to Disc Degeneration

2020

View full text Add to dashboard Cite

Introduction: This study develops and validates an accurate, computationally efficient, 3-dimensional finite element model (FEM) of the human lumbar spine. Advantages of this simplified model are shown by its application to a disc degeneration study that we demonstrate is completed in one-sixth the time required when using more complicated computed tomography (CT) scan-based models. Methods: An osseoligamentous FEM of the L1-L5 spine is developed using simple shapes based on average anatomical dimensions of key features of the spine rather than CT scan images. Pure moments of 7.5 Nm and a compressive follower load of 1000 N are individually applied to the L1 vertebra. Validation is achieved by comparing rotations and intradiscal pressures to other widely accepted FEMs and in vitro studies. Then degenerative disc properties are modeled and rotations calculated. Required computation times are compared between the model presented in this paper and other models developed using CT scans. Results: For the validation study, parameter values for a healthy spine were used with the loading conditions described above. Total L1-L5 rotations for flexion, extension, lateral bending, and axial rotation under pure moment loading were calculated as 20.38, 10.78, 19.78, and 10.38, respectively, and under a compressive follower load, maximum intradiscal pressures were calculated as 0.68 MPa. These values compare favorably with the data used for validation. When studying the effects of disc degeneration, the affected segment is shown to experience decreases in rotations during flexion, extension, and lateral bending (24%-56%), while rotations are shown to increase during axial rotation (14%-40%). Adjacent levels realize relatively minor changes in rotation (1%-6%). This parametric study required 17.5 hours of computation time compared to more than 4 days required if utilizing typical published CT scan-based models, illustrating one of the primary advantages of the model presented in this article. Conclusions: The FEM presented in this article produces a biomechanical response comparable to widely accepted, complex, CT scan-based models and in vitro studies while requiring much shorter computation times. This makes the model ideal for conducting parametric studies of spinal pathologies and spinal correction techniques.

show abstract

Section: Advantages Of a Simplified Cemmentioning

confidence: 99%

Development and Validation of a Computationally Efficient Finite Element Model of the Human Lumbar Spine: Application to Disc Degeneration

2020

View full text Add to dashboard Cite

show abstract

“…Therefore, open surgical removal of the inferior 2/3 lamina, inferior articular process, and partially hypertrophic and cohesive superior articular process (it is the decompression range of transforaminal lumbar interbody fusion) is necessary [5]. However, more than 75% of unilateral or bilateral facetectomy can cause iatrogenic instability to the lumbar spine [6][7][8][9]; thus, supplement with lumbar fusion and pedicel screw fixation is necessary for minimizing the potential risk of future instability and deformity.…”

Section: Introductionmentioning

confidence: 99%

Posterolateral fusion combined with posterior decompression shows superiority in the treatment of severe lumbar spinal stenosis without lumbar disc protrusion or prolapse: a retrospective cohort study

et al. 2020

View full text Add to dashboard Cite

Background: Currently, discectomy and posterior decompression combined with lumbar circumferential fusion (CF) have been accepted as a major procedure for severe lumbar spinal stenosis (LSS). However, studies on severe LSS without protruded intervertebral disc to minimize study bias are lacking. We aimed to investigate the effectiveness of sole posterior decompression with lumbar posterolateral fusion (PLF) and the necessity of discectomy and CF in patients with severe LSS without lumbar disc protrusion or prolapse. Methods: This retrospective cohort study included 153 severe LSS patients without lumbar disc protrusion or prolapse who were admitted in a tertiary spine center with at least a 2-year follow-up between January 2014 and August 2017. Patients were divided into the PLF (n = 77; those who underwent posterior decompression with PLF in 1-3 segments) or CF (n = 76; those who underwent posterior decompression and discectomy with CF in 1-3 segments) groups. Pedicle screw instrumentation was applied to avoid postoperative instability. Clinical outcomes were assessed by visual analog scale (VAS), Oswestry Disability Index (ODI), and Japanese Orthopedic Association Score (JOA, lumbar pain score). Duration of operation, blood loss, surgical cost, and postoperative complications were analyzed. Height of intervertebral space, lumbar lordosis, and bone union were confirmed by lumbar radiography or computed tomography. Results: Both groups achieved significant improvement in JOA, ODI, and VAS compared with preoperative values (P < 0.001), but without significant difference between the two groups. Both groups achieved high fusion rate without difference and correction of lumbar lordosis and intervertebral space height (P < 0.001), especially in the CF group (P < 0.05). Duration of operation, blood loss, and operation cost were significantly higher in the CF group than in the PLF group (P < 0.001). Eight complications were found in both groups (1, PLF group; 7, CF group; P < 0.05). Conclusions: After posterior decompression, PLF successfully achieves bony fusion and symptom relief with lower complication rate, lesser surgical blood loss, shorter operative time, and lesser cost than CF. Thus, sole posterior decompression with PLF is an effective treatment for severe LSS without lumbar disc protrusion or prolapse.

show abstract

“…For foraminoplasty, various range of proportions and portions of facet joints could be removed, depending on the surgical approaches, surgical technique, surgeons and foraminoplasty way. Although many groups 13–16 have investigated the effect of various resection proportion of facet joints on lumbar biomechanics, and reported that lumbar stability was not significantly affected only if the range of graded facetectomy exceeded 50%, there have been few studies comparing the biomechanical behavior of adjacent segments after foraminoplasty was performed on different facet portions.…”

Section: Discussionmentioning

confidence: 99%

“…Erbulut 15 established FE models of graded facetectomy (total left unilateral medial facetectomy, total bilateral facetectomy, 50% unilateral medial facetectomy, and 75% unilateral medial facetectomy) to evaluate the effect on lumbar ROM. In order to get a more comprehensive biomechanical understanding of the environment in the spine after graded facetectomy, Zeng et al 16 . did a further FE study which investigated the biomechanical effect of graded facetectomy on intervertebral ROM, intradiscal pressure, facet joint forces, and maximum von Mises equivalent stresses.…”

Section: Introductionmentioning

confidence: 99%

Effect of Percutaneous Endoscopic Lumbar Foraminoplasty of Different Facet Joint Portions on Lumbar Biomechanics: A Finite Element Analysis

Zhou

Xie

et al. 2020

Orthopaedic Surgery

View full text Add to dashboard Cite

Objective To evaluate the influence of percutaneous endoscopic lumbar foraminoplasty of different facet joint portions on segmental range of motion (ROM) and intradiscal pressure (IDP) of L3/L4 and L4/L5 motion segments by establishing three dimensional finite element (FE) model. Method Computed tomography images of a male adult volunteer of appropriate age and in good condition both mentally and physically. Obtained data was used in this study from July 2020 to December 2020, and an intact L3–5 three dimensional finite element model was successfully constructed using ANSYS and MIMICS software (model M1). The M1 was modified to simulate the foraminoplasty of different facet joint portions, with unilateral cylindrical excision (diameter = 0.75 cm) performed on the tip (model M2) and the base (model M3) of right L5 superior facet elements along with surrounding capsular ligaments, respectively. Under the same loading conditions, the ROM and IDP of L3/4 and L4/L5 segments in states of forward flexion, backward extension, left lateral bending, right lateral bending, left axial rotation and right axial rotation were all compared. Result Compared with the intact model in backward extension, M2 increased the ROM of L4/5 segment by 9.4% and IDP by 11.7%, while the ROM and IDP of M3 changed only slightly. In right axial rotation, M2 and M3 increased the ROM of L4/5 segment by 17.9% and by 3.6%, respectively. In left axial rotation, M2 and M3 increased the ROM of L4/L5 segment by 7.14% and 3.6%, respectively. As for other states including forward flexion, left lateral bending, right lateral bending, the ROM and IDP were not significantly distinct between these two models. While focusing on L3/L4 segment, obviously changes in the ROM and IDP have not been presented and neither M2 nor M3 changed in any loading condition. Conclusion This study provides evidence that the base‐facet foraminoplasty of L5 superior facet provided a higher segmental stability compared with the tip‐facet foraminoplasty in flexion and axial rotation. Meanwhile, it also shows the two types of foraminoplasty make few differences to the L4/5 segmental biomechanics. Besides, it does not appear to impact the stability of L3/L4 in six states of forward flexion, backward extension, left lateral bending, right lateral bending, left axial rotation and right axial rotation when superior facet of L5 was partially removed. These findings might be useful in understanding biomechanics of the lumbar spine after foraminoplasty performed on different portions of the facet, thus providing endoscopic surgeons a better reference for operational approach to maintain the function and mobility of the spine.

show abstract

Effect of Graded Facetectomy on Lumbar Biomechanics

Cited by 36 publications

References 30 publications

Development and Validation of a Computationally Efficient Finite Element Model of the Human Lumbar Spine: Application to Disc Degeneration

Development and Validation of a Computationally Efficient Finite Element Model of the Human Lumbar Spine: Application to Disc Degeneration

Posterolateral fusion combined with posterior decompression shows superiority in the treatment of severe lumbar spinal stenosis without lumbar disc protrusion or prolapse: a retrospective cohort study

Effect of Percutaneous Endoscopic Lumbar Foraminoplasty of Different Facet Joint Portions on Lumbar Biomechanics: A Finite Element Analysis

Contact Info

Product

Resources

About