1
|
Bereczki F, Turbucz M, Pokorni AJ, Hajnal B, Ronai M, Klemencsics I, Lazary A, Eltes PE. The effect of polymethylmethacrylate augmentation on the primary stability of stand-alone implant construct versus posterior stabilization in oblique lumbar interbody fusion with osteoporotic bone quality- a finite element study. Spine J 2024; 24:1323-1333. [PMID: 38307174 DOI: 10.1016/j.spinee.2024.01.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 01/26/2024] [Accepted: 01/27/2024] [Indexed: 02/04/2024]
Abstract
BACKGROUND CONTEXT Oblique lumbar interbody fusion (OLIF) can provide an ideal minimally invasive solution for achieving spinal fusion in an older, more frail population where decreased bone quality can be a limiting factor. Stabilization can be achieved with bilateral pedicle screws (BPS), which require additional incisions and longer operative time. Alternatively, a novel self-anchoring stand-alone lateral plate system (SSA) can be used, where no additional incisions are required. Based on the relevant literature, BPS constructs provide greater primary biomechanical stability compared to lateral plate constructs, including SSA. This difference is further increased by osteoporosis. Screw augmentation in spinal fusion surgeries is commonly used; however, in the case of OLIF, it is a fairly new concept, lacking a consensus-based guideline. PURPOSE This comparative finite element (FE) study aimed to investigate the effect of PMMA screw augmentation on the primary stability of a stand-alone implant construct versus posterior stabilization in OLIF with osteoporotic bone quality. STUDY DESIGN The biomechanical effect of screw augmentation was studied inside an in-silico environment using computer-aided FE analysis. METHODS A previously validated and published L2-L4 FE model with normal and osteoporotic bone material properties was used. Geometries based on the OLIF implants (BPS, SSA) were created and placed inside the L3-L4 motion segment with increasing volumes (1-6 cm3) of PMMA augmentation. A follower load of 400 N and 10 Nm bending moment (in the three anatomical planes) were applied to the surgical FE models with different bone material properties. The operated L3-L4 segmental range of motion (ROM), the inserted cage's maximal caudal displacements, and L4 cranial bony endplate principal stress values were measured. RESULTS The nonaugmented values for the BPS construct were generally lower compared to SSA, and the difference was increased by osteoporosis. In osteoporotic bone, PMMA augmentation gradually decreased the investigated parameters and the difference between the two constructs as well. Between 3 cm3 and 4 cm3 of injected PMMA volume per screw, the difference between augmented SSA and standard BPS became comparable. CONCLUSIONS Based on this study, augmentation can enhance the primary stability of the constructs and decrease the difference between them. Considering leakage as a possible complication, between 3 cm3 and 4 cm3 of injected PMMA per screw can be an adequate amount for SSA augmentation. However, further in silico, and possibly in vitro and clinical testing is required to thoroughly understand the investigated biomechanical aspects. CLINICAL SIGNIFICANCE This study sheds light on the possible biomechanical advantage offered by augmented OLIF implants and provides a theoretical augmentation amount for the SSA construct. Based on the findings, the concept of an SSA device with PMMA augmentation capability is desirable.
Collapse
Affiliation(s)
- Ferenc Bereczki
- In Silico Biomechanics Laboratory, National Center for Spinal Disorders, Királyhágó Str. 1-3, Budapest, Hungary; School of PhD Studies, Semmelweis University, Üllői Str. 26, Budapest, Hungary
| | - Mate Turbucz
- In Silico Biomechanics Laboratory, National Center for Spinal Disorders, Királyhágó Str. 1-3, Budapest, Hungary; School of PhD Studies, Semmelweis University, Üllői Str. 26, Budapest, Hungary
| | - Agoston Jakab Pokorni
- In Silico Biomechanics Laboratory, National Center for Spinal Disorders, Királyhágó Str. 1-3, Budapest, Hungary; School of PhD Studies, Semmelweis University, Üllői Str. 26, Budapest, Hungary
| | - Benjamin Hajnal
- In Silico Biomechanics Laboratory, National Center for Spinal Disorders, Királyhágó Str. 1-3, Budapest, Hungary; School of PhD Studies, Semmelweis University, Üllői Str. 26, Budapest, Hungary
| | - Marton Ronai
- National Center for Spinal Disorders, Királyhágó Str. 1-3, Budapest, Hungary
| | - Istvan Klemencsics
- National Center for Spinal Disorders, Királyhágó Str. 1-3, Budapest, Hungary
| | - Aron Lazary
- In Silico Biomechanics Laboratory, National Center for Spinal Disorders, Királyhágó Str. 1-3, Budapest, Hungary; Department of Spine Surgery, Department of Orthopaedics, Semmelweis University, Üllői Str. 78/b, Budapest, Hungary
| | - Peter Endre Eltes
- In Silico Biomechanics Laboratory, National Center for Spinal Disorders, Királyhágó Str. 1-3, Budapest, Hungary; Department of Spine Surgery, Department of Orthopaedics, Semmelweis University, Üllői Str. 78/b, Budapest, Hungary.
| |
Collapse
|
2
|
Fan ZQ, Yan XA, Li BF, Shen E, Xu X, Wang H, Zhuang Y. Prevalence of osteoporosis in spinal surgery patients older than 50 years: A systematic review and meta-analysis. PLoS One 2023; 18:e0286110. [PMID: 37228067 DOI: 10.1371/journal.pone.0286110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 05/09/2023] [Indexed: 05/27/2023] Open
Abstract
INTRODUCTION In spine surgery, poor bone condition is associated with several complications like adjacent segment fractures, proximal junctional kyphosis, and screw loosening. Our study explored the prevalence of osteoporosis in spinal surgery patients older than 50 years through a systematic review and meta-analysis. METHODS This systematic review and meta-analysis were conducted according to the PRISMA criteria. Three electronic databases, including PubMed, EMBASE, and Web of Science, were searched from inception to August 2022. We used the random-effects model to calculate the overall estimates, and the heterogeneity was measured using Cochran's Q and I2 tests. Meta-regression and subgroup analyses were used to determine the source of the heterogeneity. RESULTS Based on the inclusion and criteria, we chose ten studies with 2958 individuals for our analysis. The prevalence of osteoporosis, osteopenia, and osteoporosis/osteopenia in the spinal surgery patients was 34.2% (95%CI: 24.5%-44.6%), 43.5% (95%CI: 39.8%-47.2%), and 78.7% (95%CI: 69.0%-87.0%), respectively. Regarding different diagnoses, the prevalence was highest in patients with lumbar scoliosis (55.8%; 95%CI: 46.8%-64.7%) and the lowest in patients with cervical disc herniation (12.9%; 95%CI: 8.1%-18.7%). In age groups 50-59, 50-69,70-79, the prevalence was 27.8%, 60.4%, 75.4% in females, and 18.9%, 17.4%, 26.1% in males. CONCLUSIONS This study showed a high prevalence of osteoporosis in patients undergoing spine surgery, especially in females, people of older age, and patients who received degenerative scoliosis and compression fractures. Current osteoporosis screening standards for patients undergoing spine surgery may not be adequate. Orthopedic specialists should make more efforts regarding preoperative osteoporosis screening and treatment.
Collapse
Affiliation(s)
- Zhi-Qiang Fan
- Department of Pelvic and Acetabular Surgery, HongHui Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Xin-An Yan
- Department of Pelvic and Acetabular Surgery, HongHui Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Bao-Feng Li
- Department of Pelvic and Acetabular Surgery, HongHui Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Erdong Shen
- Department of Pelvic and Acetabular Surgery, HongHui Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Xin Xu
- Department of Pelvic and Acetabular Surgery, HongHui Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Hu Wang
- Department of Pelvic and Acetabular Surgery, HongHui Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Yan Zhuang
- Department of Pelvic and Acetabular Surgery, HongHui Hospital, Xi'an Jiaotong University, Xi'an, China
| |
Collapse
|
3
|
Dai H, Liu Y, Han Q, Zhang A, Chen H, Qu Y, Wang J, Zhao J. Biomechanical comparison between unilateral and bilateral percutaneous vertebroplasty for osteoporotic vertebral compression fractures: A finite element analysis. Front Bioeng Biotechnol 2022; 10:978917. [PMID: 36159704 PMCID: PMC9495612 DOI: 10.3389/fbioe.2022.978917] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 08/15/2022] [Indexed: 11/23/2022] Open
Abstract
Background and objective: The osteoporotic vertebral compression fracture (OVCF) has an incidence of 7.8/1000 person-years at 55–65 years. At 75 years or older, the incidence increases to 19.6/1000 person-years in females and 5.2–9.3/1000 person-years in males. To solve this problem, percutaneous vertebroplasty (PVP) was developed in recent years and has been widely used in clinical practice to treat OVCF. Are the clinical effects of unilateral percutaneous vertebroplasty (UPVP) and bilateral percutaneous vertebroplasty (BPVP) the same? The purpose of this study was to compare biomechanical differences between UPVP and BPVP using finite element analysis. Materials and methods: The heterogeneous assignment finite element (FE) model of T11-L1 was constructed and validated. A compression fracture of the vertebral body was performed at T12. UPVP and BPVP were simulated by the difference in the distribution of bone cement in T12. Stress distributions and maximum von Mises stresses of vertebrae and intervertebral discs were compared. The rate of change of maximum displacement between UPVP and BPVP was evaluated. Results: There were no obvious high-stress concentration regions on the anterior and middle columns of the T12 vertebral body in BPVP. Compared with UPVP, the maximum stress on T11 in BPVP was lower under left/right lateral bending, and the maximum stress on L1 was lower under all loading conditions. For the T12-L1 intervertebral disc, the maximum stress of BPVP was less than that of UPVP. The maximum displacement of T12 after BPVP was less than that after UPVP under the six loading conditions. Conclusion: BPVP could balance the stress of the vertebral body, reduce the maximum stress of the intervertebral disc, and offer advantages in terms of stability compared with UPVP. In summary, BPVP could reduce the incidence of postoperative complications and provide promising clinical effects for patients.
Collapse
Affiliation(s)
| | | | | | | | | | - Yang Qu
- *Correspondence: Yang Qu, ; Jincheng Wang,
| | | | | |
Collapse
|
4
|
Predicting pullout strength of pedicle screws in broken bones from X-ray images. J Mech Behav Biomed Mater 2022; 134:105366. [PMID: 35870229 DOI: 10.1016/j.jmbbm.2022.105366] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/23/2022] [Accepted: 07/09/2022] [Indexed: 12/19/2022]
Abstract
Pedicle screw fixation is one of the most common procedures used in spinal fusion surgery. The screw loosening is a major concern, which may be caused by broken pedicles. In vitro pullout tests or insertion torque are the main approaches for assessing the stability of the screw; however, direct evidence was lacking for clinical human spines. Here, we aim to provide a model that can predict the pullout strengths of pedicle screws in various pedicle conditions from X-ray images. A weighted embedded bone volume (EBV) model is proposed for pullout strengths prediction by considering the bone heterogeneity and confinement of the screw. We showed that the pullout strength is proportional to the EBV for homogeneous bone and the weighted EBV for layered composite bone. The proposed weighted EBV model is validated with in vitro Sawbones® pullout experiments. The results show that the model has better accuracy than the simple EBV model, with a coefficient of determination of 0.94. The proposed weighted EBV model can help assess the stability of a pedicle screw in a broken pedicle by simply examining 2D X-ray images.
Collapse
|
5
|
Guo H, Huang H, Shao Y, Qin Q, Liang D, Zhang S, Tang Y. Risk Factors for Pulmonary Cement Embolism (PCE) After Polymethylmethacrylate Augmentation: Analysis of 32 PCE Cases. Neurospine 2022; 18:806-815. [PMID: 35000335 PMCID: PMC8752710 DOI: 10.14245/ns.2142616.308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 09/08/2021] [Indexed: 02/06/2023] Open
Abstract
Objective Pulmonary cement embolism (PCE) is an underestimated but potentially fatal complication after cement augmentation. Although the treatment and follow-up of PCE have been reported in the literature, the risk factors for PCE are so far less investigated. This study aims to identify the preoperative and intraoperative risk factors for the development of PCE.
Methods A total of 1,373 patients treated with the polymethylmethacrylate (PMMA) augmentation technique were retrospectively included. Patients with PCE were divided into vertebral augmentation group and screw augmentation group. Possible risk factors were collected as follows: age, sex, bone mineral density, body mass index, diagnosis, comorbidity, surgical procedure, type of screw, augmented level, number of augmented vertebrae, fracture severity, presence of intravertebral cleft, cement volume, marked leakage in the paravertebral venous plexus, and periods of surgery. Binary logistic regression analyses were used to analyze independent risk factors for PCE.
Results PCE was identified in 32 patients, with an incidence rate of 2.33% (32 of 1,373). For patients who had undergone vertebral augmentation, marked leakage in the paravertebral venous plexus (odds ratio [OR], 1.2; 95% confidence interval [CI], 0.1–10.3; p=0.000) and previous surgery (OR, 16.1; 95% CI, 4.2–61.0; p=0.007) were independent risk factors for PCE. Regarding patients who had undergone screw augmentation, the marked leakage in the paravertebral venous plexus (OR, 4.2; 95% CI, 0.5–37.3; p=0.004) was the main risk factor.
Conclusion Marked leakage in the paravertebral venous plexus and previous surgery were significant risk factors related to PCE. Paravertebral leakage and operator experience should be concerned when performing PMMA augmentation.
Collapse
Affiliation(s)
- Huizhi Guo
- The first Institute of Clinical Medicine, Guangzhou University of Chinese Medicine, Guangzhou, China.,Spine Surgery Department, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Huasheng Huang
- The first Institute of Clinical Medicine, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yang Shao
- The first Institute of Clinical Medicine, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Qiuli Qin
- The first Institute of Clinical Medicine, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - De Liang
- Spine Surgery Department, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Shuncong Zhang
- Spine Surgery Department, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yongchao Tang
- Spine Surgery Department, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| |
Collapse
|
6
|
Finite Element Method for the Evaluation of the Human Spine: A Literature Overview. J Funct Biomater 2021; 12:jfb12030043. [PMID: 34449646 PMCID: PMC8395922 DOI: 10.3390/jfb12030043] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 07/23/2021] [Accepted: 07/29/2021] [Indexed: 02/07/2023] Open
Abstract
The finite element method (FEM) represents a computer simulation method, originally used in civil engineering, which dates back to the early 1940s. Applications of FEM have also been used in numerous medical areas and in orthopedic surgery. Computing technology has improved over the years and as a result, more complex problems, such as those involving the spine, can be analyzed. The spine is a complex anatomical structure that maintains the erect posture and supports considerable loads. Applications of FEM in the spine have contributed to the understanding of bone biomechanics, both in healthy and abnormal conditions, such as scoliosis, fractures (trauma), degenerative disc disease and osteoporosis. However, since FEM is only a digital simulation of the real condition, it will never exactly simulate in vivo results. In particular, when it concerns biomechanics, there are many features that are difficult to represent in a FEM. More FEM studies and spine research are required in order to examine interpersonal spine stiffness, young spine biomechanics and model accuracy. In the future, patient-specific models will be used for better patient evaluations as well as for better pre- and inter-operative planning.
Collapse
|
7
|
Zhang L, Li HM, Zhang R, Zhang H, Shen CL. Biomechanical Changes of Adjacent and Fixed Segments Through Cortical Bone Trajectory Screw Fixation versus Traditional Trajectory Screw Fixation in the Lumbar Spine: A Finite Element Analysis. World Neurosurg 2021; 151:e447-e456. [PMID: 33895371 DOI: 10.1016/j.wneu.2021.04.061] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 01/12/2023]
Abstract
OBJECTIVE The finite element method was used to investigate the biomechanical adjustments of adjacent and fixed segments after lumbar fusion and fixation with traditional trajectory (TT) and cortical bone trajectory (CBT) screws. METHODS The model used was a validated nonlinearly L3-S1 finite element model. Interbody fusion cages and 2 types of screws were used to work on the L4-L5. To simulate flexion, extension, lateral bending, and axial rotation, all models were loaded in 3 planes with a compressive pre-load of 400 N and a bending moment of 7.5 N/m. Under various loading conditions, the range of motion (ROM), peak Von Mises stress of the vertebral body, stress of the intervertebral disc, stress of the facet joints, stress of the endplate, and stress of internal fixation were compared. RESULTS In all instrumentation models, the ROM at fixed segments decreased. At adjacent segments, the ROM of the CBT model was greater than that of the TT model. The CBT model had a greater peak Von Mises stress of the L4 and L5 vertebral bodies, as well as greater stress of internal fixation, than the TT model. Furthermore, as compared with the TT model, the CBT model's facet joint and endplate stress were lower at fixed segments but higher at adjacent segments. The stress on the L3-L4 and L5-S1 intervertebral discs in the CBT and TT models, on the other hand, was nearly equivalent. CONCLUSIONS At the fixed section, CBT may provide slightly better stability, endplate tension, and facet joint stress than TT. The greater ROM, endplate stress, and facet joint stress of CBT in adjacent segments, on the other hand, should be taken into account in the future.
Collapse
Affiliation(s)
- Lai Zhang
- Department of Orthopedics & Spine Surgery, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Hui-Min Li
- Department of Orthopedics & Spine Surgery, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Renjie Zhang
- Department of Orthopedics & Spine Surgery, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Huaqing Zhang
- Department of Orthopedics & Spine Surgery, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Cai-Liang Shen
- Department of Orthopedics & Spine Surgery, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
| |
Collapse
|