Treatment of L5-S1 Floating Calcified Lumbar Disc Herniation with Percutaneous Endoscopic Interlaminar Discectomy.

OBJECTIVE: The floating calcified tissue in floating calcified lumbar disc herniation (FCLDH) is hard and often adheres to the dura mater, which can easily cause nerve root damage during surgery, making the operation challenging. We proposed the classification of FCLDH and a new technique for removing floating calcified tissue and reported the clinical efficacy and safety of this new technique in clinical practice. METHODS: From January 2019 to October 2021, 24 patients (13 males and 11 females, 46.4 ± 7.72 years) with L5-S1 floating calcified lumbar disc herniation were treated with percutaneous endoscopic interlaminar discectomy (PEID). According to FCLDH classification, a total of Type Ia: nine cases, Type Ib: five cases, Type IIa: four cases, and Type IIa: six cases were included. The visual analogue scale (VAS) and Oswestry disability index (ODI) were recorded pre-operatively and 3 days postoperatively, 6 months postoperatively, and at the last follow-up. The postoperative curative effect was evaluated according to the modified MacNab criteria. Computed tomography (CT) and magnetic resonance imaging (MRI) of the lumbar spine were performed 3 days after surgery to evaluate the efficacy of the surgery. RESULTS: All patients successfully underwent PEID. The VAS and ODI scores at 3 days postoperatively, 6 months postoperatively, and at the last follow-up were significantly improved and statistically significant compared to those of the preoperative period (p < 0.05). All the patients were followed up for 12-24 months (mean, 16.6 ± 4.6 months). At the last follow-up, according to the modified MacNab criteria, 15 cases were excellent, eight were good, and one was fair. The combined excellent and good rate was 95.83% (23/24). Postoperative review revealed that all floating calcified tissues were effectively removed and the nerve roots were adequately decompressed without complications such as cerebrospinal fluid leakage and lumbar spine infection. CONCLUSION: The classification of FCLDH we proposed can well guide the selection of surgical plans. PEID combined with floating calcified tissue removal technology has good efficacy in the treatment of L5-S1 FCLDH, ensuring accurate removal of calcified tissue, reducing complications and improving the quality of life of affected individuals.

Ginsenoside Rb2 exhibits therapeutic value for male osteoporosis in orchiectomy mice by suppressing osteoclastogenesis and modulating NF-κB/MAPK signaling pathways.

Osteoporosis (OP) is a systemic disorder characterized by decreased bone mass as well as deteriorated microarchitecture. Although OP in men is common, it has received much less attention than that in women. Ginseng, a famous traditional herb in Asia, is used to strengthen and repair bones by invigorating vital bioenergy and maintaining body homeostasis in dietary intake and clinical applications. However, there is currently no study investigating the impact of ginseng and its active compounds on male osteoporosis. In this study, RNA sequencing and bioinformatic analysis were conducted to reveal the influence of Ginsenoside-Rb2 on RAW264.7 cells and its underlying signaling pathways. The potential anti-osteoporosis effects of Rb2 as well as its molecular mechanisms were elucidated in RAW264.7 cells and BMMs by TRAP staining, F-actin belt staining, qRT-PCR and WB. Moreover, orchiectomy (ORX) was utilized to demonstrate the influence of Rb2 on bone mass loss in vivo by micro-CT scanning, and H&E, TRAP, and IHC staining. The results suggested that Rb2 suppressed osteoclastogenesis and mitigated bone loss in orchiectomy mice through NF-κB/MAPK signaling pathways. These findings indicate that ginseng as well as its active component Rb2 have potential therapeutic value in the management of osteoporosis in men.

Functional characterization of group â ¡ interferon, IFNf in the acipenseriform fish, Chinese sturgeon (Acipenser sinensis).

Teleost fish possess a diversity of type Ⅰ interferons (IFNs) repertoire, which play a crucial role in antiviral and antimicrobial immune responses. In our previous study, IFNe1-3 and IFNb were identified and cloned from Chinese sturgeon (Acipenser sinensis), an acipenseriform fish. However, the absence of Chinese sturgeon genome data has left the question of whether there are other type Ⅰ IFN members in this species unresolved. In this study, we have identified and characterized a novel IFN, IFNf in Chinese sturgeon (AsIFNf). Bioinformatics analysis revealed that the AsIFNf contains a unique disulfide bond (2 cysteines) located in the second exon and fifth exon region, distinguishing it from other reported teleost type I IFNs. Meanwhile, qPCR results showed that AsIFNf mRNA was detectable in all examined tissues and up-regulated in the spleen or kidney in response to poly I: C, Citrobacter freundii, and Spring Viremia of Carp Virus (SVCV), but not by LPS. Furthermore, compared to recombinant AsIFNe2 protein (rAsIFNe2), rAsIFNf exhibited a stronger protective effect on Chinese sturgeon fin cells against SVCV and also induced higher expression of antiviral genes Mx and viperin. Importantly, AsIFNf displayed characteristics similar to antimicrobial peptides (AMPs) with a positive charge and demonstrated a broad spectrum of antimicrobial activity in vitro. These findings provide a theoretical foundation for understanding the primitive structure and function of interferon, as well as deepening our comprehension of the innate immune system and disease defense in the endangered Chinese sturgeon.

[Advances in surgical strategies for ossification of posterior longitudinal ligament involving the C 2 segment].

Objective: To evaluate the application of surgical strategies for the treatment of cervical ossification of the posterior longitudinal ligament (OPLL) involving the C 2 segment. Methods: The literature about the surgery for cervical OPLL involving C 2 segment was reviewed, and the indications, advantages, and disadvantages of surgery were summarized. Results: For cervical OPLL involving the C 2 segments, laminectomy is suitable for patients with OPLL involving multiple segments, often combined with screw fixation, and has the advantages of adequate decompression and restoration of cervical curvature, with the disadvantages of loss of cervical fixed segmental mobility. Canal-expansive laminoplasty is suitable for patients with positive K-line and has the advantages of simple operation and preservation of cervical segmental mobility, and the disadvantages include progression of ossification, axial symptoms, and fracture of the portal axis. Dome-like laminoplasty is suitable for patients without kyphosis/cervical instability and with negative R-line, and can reduce the occurrence of axial symptoms, with the disadvantage of limited decompression. The Shelter technique is suitable for patients with single/double segments and canal encroachment >50% and allows for direct decompression, but is technically demanding and involves risk of dural tear and nerve injury. Double-dome laminoplasty is suitable for patients without kyphosis/cervical instability. Its advantages are the reduction of damage to the cervical semispinal muscles and attachment points and maintenance of cervical curvature, but there is progress in postoperative ossification. Conclusion: OPLL involving the C 2 segment is a complex subtype of cervical OPLL, which is mainly treated through posterior surgery. However, the degree of spinal cord floatation is limited, and with the progress of ossification, the long-term effectiveness is poor. More research is needed to address the etiology of OPLL and to establish a systematic treatment strategy for cervical OPLL involving the C 2 segment.

Comparison of pedicle screw fixation with or without cement augmentation for treating single-segment isthmic spondylolisthesis in the osteoporotic spine.

The present study examined the necessity of cement-augmented pedicle screw fixation in osteoporotic patients with single-segment isthmic spondylolisthesis.Fifty-nine cases were reviewed retrospectively. Thirty-three cases were in the polymethylmethacrylate-augmented pedicle screw (PMMA-PS) group, and the other 26 cases were in the conventional pedicle screw (CPS) group. Evaluation data included operation time, intraoperative blood loss, hospitalization cost, hospitalization days, rates of fusion, screw loosening, bone cement leakage, visual analogue scale (VAS) scores, Oswestry disability index (ODI), lumbar lordosis (LL), pelvic tilt (PT) and sacral slope (SS).The operation time and blood loss in the CPS group decreased significantly compared to those in the PMMA-PS group. The average hospitalization cost of the PMMA-PS group was significantly higher than that of the CPS group. There was no significant difference in the average hospital stay between the 2 groups. The initial and last follow-up postoperative VAS and ODI scores improved significantly in the two groups. There were no significant differences in VAS and ODI between the 2 groups at each time point. The last postoperative spine-pelvic parameters were significantly improved compared with those preoperatively. In the PMMA-PS group, the fusion rate was 100%. The fusion rate was 96.15% in the CPS group. No significant difference was found between the two groups for the fusion rate. Nine patients in the PMMA-PS group had bone cement leakage. There was no screw loosening in the PMMA-PS group. There were 2 cases of screw loosening in the CPS group. There were no significant differences in screw loosening, postoperative adjacent segment fractures, postoperative infection or postoperative revision between the 2 groups. The use of PMMA-PS on a regular basis is not recommended in posterior lumbar interbody fusion for the treatment of single-segment isthmic spondylolisthesis with osteoporosis.

Maqui Berry and Ginseng Extracts Reduce Cigarette Smoke-Induced Cell Injury in a 3D Bone Co-Culture Model.

Cigarette smoking-induced oxidative stress has harmful effects on bone metabolism. Maqui berry extract (MBE) and ginseng extract (GE) are two naturally occurring antioxidants that have been shown to reduce oxidative stress. By using an osteoblast and osteoclast three-dimensional co-culture system, we investigated the effects of MBE and GE on bone cells exposed to cigarette smoke extract (CSE). The cell viability and function of the co-culture system were measured on day 14. Markers of bone cell differentiation and oxidative stress were evaluated at gene and protein levels on day 7. The results showed that exposure to CSE induced osteoporotic-like alterations in the co-culture system, while 1.5 µg/mL MBE and 50 µg/mL GE improved CSE-impaired osteoblast function and decreased CSE-induced osteoclast function. The molecular mechanism of MBE and GE in preventing CSE-induced bone cell damage is linked with the inhibition of the NF-κB signaling pathway and the activation of the Nrf2 signaling pathway. Therefore, MBE and GE can reduce CSE-induced detrimental effects on bone cells and, thus, prevent smoking-induced alterations in bone cell homeostasis. These two antioxidants are thus suitable supplements to support bone regeneration in smokers.

Pathogenicity of Plesiomonas shigelloides and Citrobacter freundii isolated from the endangered Chinese sturgeon (Acipenser sinensis).

Chinese sturgeon (Acipenser sinensis) is an indigenous species of China and is listed as a critically endangered species. Recently, second filial generations of Chinese sturgeon in the Yangtze River Fisheries Research Institute suffered from a severe disease. In this study, two kinds of pathogenic bacteria were isolated from diseased sturgeon and identified as Plesiomonas shigelloides and Citrobacter freundii, based on 16S rDNA gene sequence alignment analysis. Antimicrobial susceptibility testing showed that P. shigelloides was resistant to ampicillin, penicillin, midecamycin, oxacillin, and clindamycin; and sensitive to tocefatriaxone, piperacillin, cefoperazone, cefazolin, and ciprofloxacin. C. freundii was resistant to ampicillin, penicillin, midecamycin, oxacillin, and clindamycin; and sensitive to chloramphenicol, cefuroxime, norfloxacin, ciprofloxacin, and ceftazidime. The median lethal dose (LD50) values of P. shigelloides and C. freundii were 4.50 × 103 colony forming units (CFU)/g and 3.20 × 103 CFU/g, respectively. Clinical symptoms of challenged sturgeons were the same as those of naturally infected sturgeons. Histopathological examination disclosed severe damage in the viscera of P. shigelloides and C. freundii-infected sturgeons. This is the first report suggesting that P. shigelloides infection is associated with mortality of Chinese sturgeon. The results of this study revealed the pathogenesis and severe pathogenicity of P. shigelloides and C. freundii in cultured Chinese sturgeon, and offer insights into the prevention and treatment of bacterial infection caused by P. shigelloides and C. freundii in cultured sturgeons.

Transcriptome Sequencing Reveals the Antiviral Innate Immunity by IFN-γ in Chinese Sturgeon Macrophages.

To further study the biological function of interferon-gamma (IFN-γ) in the Chinese sturgeon (Acipenser sinensis), we conducted a transcriptome analysis of primary macrophages induced by IFN-γ using Illumina sequencing technology. We obtained 88,879 unigenes, with a total length of 93,919,393 bp, and an average length of 1,057bp. We identified 8,490 differentially expressed genes (DEGs) between the untreated and IFN-γ-treated macrophages, with 4,599 upregulated and 3,891 downregulated. Gene ontology (GO) analysis showed that 4,044 DEGs were enriched in the biological, cellular components, and molecular function categories. Kyoto Encyclopedia of Genes and Genomes (KEGG) identified 278 immunity-related pathways enriched for the DEGs. According to the GO enrichment results, eight key immunity-related genes were screened for verification using qPCR. Results indicate that IFN-γ can activate macrophage Interferon Regulatory Factors (IRFs) and type I interferon (IFN-I), activate RIG-I-like and Toll-like receptor-related pathways, and improve the antiviral ability of macrophages in Chinese sturgeon.

Epigenetic Biomarkers Screening of Non-Coding RNA and DNA Methylation Based on Peripheral Blood Monocytes in Smokers.

This study aims to use bioinformatics methods to determine the epigenetic changes in microRNA expression and DNA methylation caused by cigarette smoking. The data of mRNA, miRNA expression, and methylation microarray were obtained from the GEO database to filter differentially expressed genes (DEGs), differentially expressed miRNAs (DEMs), and methylated CpG probes (DMPs) through the limma package. The R clusterProfile package was used for functional annotation and enrichment analysis. The protein-protein interaction (PPI) network was constructed by the String database and visualized in Cytoscape software. Starbase database was employed to predict lncRNA and CirRNA based on the sequence of miRNA, and to establish a regulatory network of ceRNA. By overlapping DEG and DEM, 107 down-miRNA-targeted up-regulated genes and 65 up-miRNA-target down-regulated genes were obtained, which were mainly enriched in autophagy signaling pathways and protein ubiquitination pathways, respectively. In addition, 324 genes with low methylation and high expression and 204 genes with high methylation and low expression were respectively related to the degeneration of the nervous system and the function of the cardiovascular system. Interestingly, 43 genes were up-regulated under the dual regulation of reduced miRNA and hypomethylation, while 14 genes were down-regulated under the dual regulation of increased miRNA and hypermethylation. Ten chemicals have been identified as putative therapeutic agents for pathological conditions caused by smoking. In addition, among these genes, HSPA4, GRB2, PRKCA, and BCL2L1 could play a fundamental role in related diseases caused by smoking and may be used as the biomarkers for precise diagnosis and targets for future therapies of smoking-related diseases.

Long-Term Outcomes of Peripheral Pulmonary Cement Embolism in Patients with Polymethylmethacrylate Augmentation: A Case Series with a Minimum Follow-Up of Five Years.

BACKGROUND: Pulmonary cement embolism (PCE) is a rare but lethal complication. However, few long-term follow-up studies have investigated PCE after polymethylmethacrylate augmentation. This study aimed to investigate both the clinical and imaging outcomes of patients with PCE during a follow-up period of at least 5 years. METHODS: A total of 1460 patients were initially included in this retrospective study. After exclusion, the clinical and imaging data were analyzed for selected patients, including the augmented level, location and length of the PCE, symptoms, therapy, migration and disintegration of the embolism, foreign body reaction, and status at follow-up. RESULTS: Twelve female patients (age range, 56-88 years) with PCE and more than 5 years of follow-up (range, 5-13 years) were eventually included. All emboli were found in subsegment pulmonary arteries and were classified as peripheral PCE. Although 2 patients experienced transient symptoms after surgery, the majority of patients (84.6%) were asymptomatic during follow-up. No other reported emboli were observed during the follow-up period. The imaging data showed that the cement embolus could remain in the initial position throughout the long-term follow-up. In terms of the length of the PCE, there was no statistically significant difference between the values post-operation and at the last follow-up time (P > 0.05). CONCLUSIONS: Patients with peripheral PCE do not develop known late complications. Moreover, polymethylmethacrylate can remain stable and inert in the pulmonary vasculature over the long term. Routine prophylactic anticoagulation may not be necessary for patients with peripheral PCE during follow-up.

Long-term efficacy and safety of bone cement-augmented pedicle screw fixation for stage III Kümmell disease.

This study aimed to evaluate the efficacy and safety of bone cement-augmented pedicle screw fixation for stage III Kümmell disease. Twenty-five patients with stage III Kümmell disease who received bone cement-augmented pedicle screw fixation at the First Affiliated Hospital of Guangzhou University of Chinese Medicine between June 2009 and December 2015 were enrolled. All patients were females with a history of osteoporosis. The vertebral Cobb angle (V-Cobb angle), the fixed segment Cobb Angle (S-Cobb angle), pelvic parameters, visual Analogue Scale (VAS) score, and Oswestry Disability Index (ODI) were assessed preoperatively, postoperatively and at the final follow-up. Complications, loosening rate, operation time, and intraoperative bleeding were recorded. The average lumbar vertebral density T-value was - 3.68 ± 0.71 SD, and the average age was 71.84 ± 5.39. The V-Cobb angle, S-Cobb angle, and Sagittal Vertical Axis (SVA) were significantly smaller postoperatively compared to the preoperative values. The VAS and ODI at 1 month after surgery were 3.60 ± 1.00 and 36.04 ± 6.12%, respectively, which were both significantly lower than before surgery (VAS: 8.56 ± 1.04, ODI: 77.80 ± 6.57%). Bone cement-augmented pedicle screw fixation is a safe and effective treatment for stage III Kümmell disease. It can effectively correct kyphosis, restore and maintain sagittal balance, and maintain spinal stability.

Comprehensive comparison of thirteen kinds of cytokine receptors from the endangered fish Chinese sturgeon (Acipenser sinensis).

The interferon receptor system in teleost fish is more complex than that in mammals. In the present study, we identified 13 cytokine receptor genes (10 interferon receptor genes and 3 IL10R2-like genes) from Chinese sturgeon (Acipenser sinensis) using RNA-sequencing. Sequence analysis indicated that these receptors had conserved domains, including signal peptides, FNⅢ, and transmembrane domains. Phylogenetic analysis suggested that they belonged to the cytokine receptor family. In the present study, we named them IFNAR1-like (CRFB5a, CRFB5b), IFNAR2-like (CRFB3a, CRFB3b), IFNGR1-like (IFNGR1), IFNGR2-like (CRFB6a, CRFB6b/IFNGR2-1, CRFB6c/IFNGR2-2, CRFB6d/IFNGR2-3, CRFB6e/IFNGR2-4) and IL10R2-like (CRFB4a, CRFB4b, CRFB4c), respectively. Constitutive expression analysis revealed that these receptor genes had potential functions in immune and non-immune tissue compartments. After stimulating with Poly (I:C), the expression fold changes of CRFB3a, CRFB4a, CRFB4b, CRFB5b, and CRFB6e/IFNGR2-4 in Chinese sturgeon were higher than those of other receptor genes, which revealed that these five genes had important functions in the immune process to resist virus invasion in the host. After stimulating with IFN gamma, the expression fold changes of CRFB3a, CRFB4a, and CRFB6b/IFNGR2-1 were higher than those other receptor genes. Based on other teleost fish interferon receptor models, we speculated that IFNAR1-like (CRFB5a, CRFB5b) and IFNAR2-like (CRFB3a, CRFB3b), comprised Chinese sturgeon type Ⅰ IFN receptors; and IFNGR1-like (IFNGR1) and IFNGR2-like (CRFB6/IFNGR2) comprised Chinese sturgeon type Ⅱ IFN receptors.

In Silico Network Analysis of Ingredients of Cornus officinalis in Osteoporosis.

BACKGROUND Cornus officinalis (CO), also known as 'Shanzhuyu', is one of the most common traditional Chinese herbs used against osteoporosis. Although previous studies have found that CO has beneficial effects in alleviating osteoporosis, its mechanisms remain unclear. MATERIAL AND METHODS In this study, we applied system bioinformatic approaches to investigate the possible therapeutic mechanisms of CO against osteoporosis. We collected the active ingredients of CO and their targets from the TCMSP, BATMAN-TCM, and ETCM databases. Next, we obtained the osteoporosis targets from differentially expressed mRNAs from the Gene Expression Omnibus (GEO) gene series (GSE35958). Next, the shared genes of the CO pharmacological targets and osteoporosis-related targets were selected to construct the protein-protein interaction network, based on the results from the STRING database. Subsequently, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were carried out by using the clusterProfiler package in R software. RESULTS In all, there were 58 unique CO compounds and 518 therapeutic targets. Based on the GO and KEGG enrichment results of 98 common genes, we selected the top 25 terms, based on the terms' P values. We found that the anti-osteoporotic effect of CO may mostly involve the regulation of calcium metabolism and reactive oxygen species, and the estrogen signaling pathway and osteoclast differentiation pathway. CONCLUSIONS We found the possible mechanisms of CO in treating osteoporosis may be based on multiple targets and pathways. We also provided a theoretical basis and promising direction for investigating the exact anti-osteoporotic mechanisms of CO.

Agent With Warm Start and Adaptive Dynamic Termination for Plane Localization in 3D Ultrasound.

Accurate standard plane (SP) localization is the fundamental step for prenatal ultrasound (US) diagnosis. Typically, dozens of US SPs are collected to determine the clinical diagnosis. 2D US has to perform scanning for each SP, which is time-consuming and operator-dependent. While 3D US containing multiple SPs in one shot has the inherent advantages of less user-dependency and more efficiency. Automatically locating SP in 3D US is very challenging due to the huge search space and large fetal posture variations. Our previous study proposed a deep reinforcement learning (RL) framework with an alignment module and active termination to localize SPs in 3D US automatically. However, termination of agent search in RL is important and affects the practical deployment. In this study, we enhance our previous RL framework with a newly designed adaptive dynamic termination to enable an early stop for the agent searching, saving at most 67% inference time, thus boosting the accuracy and efficiency of the RL framework at the same time. Besides, we validate the effectiveness and generalizability of our algorithm extensively on our in-house multi-organ datasets containing 433 fetal brain volumes, 519 fetal abdomen volumes, and 683 uterus volumes. Our approach achieves localization error of 2.52mm/10.26° , 2.48mm/10.39° , 2.02mm/10.48° , 2.00mm/14.57° , 2.61mm/9.71° , 3.09mm/9.58° , 1.49mm/7.54° for the transcerebellar, transventricular, transthalamic planes in fetal brain, abdominal plane in fetal abdomen, and mid-sagittal, transverse and coronal planes in uterus, respectively. Experimental results show that our method is general and has the potential to improve the efficiency and standardization of US scanning.

Carnosol suppresses RANKL-induced osteoclastogenesis and attenuates titanium particles-induced osteolysis.

Osteolysis is a common medical condition characterized by excessive activity of osteoclasts and bone resorption, leading to severe poor quality of life. It is essential to identify the medications that can effectively suppress the excessive differentiation and function of osteoclasts to prevent and reduce the osteolytic conditions. It has been reported that Carnosol (Car), isolated from rosemary and salvia, has anti-inflammatory, antioxidative, and anticancer effects, but its activity on osteolysis has not been determined. In this study, we found that Car has a strong inhibitory effect on the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation dose-dependently without any observable cytotoxicity. Moreover, Car can inhibit the RANKL-induced osteoclastogenesis and resorptive function via suppressing NFATc1, which is a result of affecting MAPK, NF-κB and Ca2+ signaling pathways. Moreover, the particle-induced osteolysis mouse model confirmed that Car could be effective for the treatment of bone loss in vivo. Taken together, by suppressing the formation and function of RANKL-induced osteoclast, Car, may be a therapeutic supplementary in the prevention or the treatment of osteolysis.

Risk Factors for Pulmonary Cement Embolism (PCE) After Polymethylmethacrylate Augmentation: Analysis of 32 PCE Cases.

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.

Selective cement augmentation of cranial and caudal pedicle screws provides comparable stability to augmentation on all segments in the osteoporotic spine: a finite element analysis.

BACKGROUND: Cement-augmented pedicle screw instrumentation (CAPSI) has been proven to significantly increase the biomechanical stability in the osteoporotic lumbar spine. However, besides the merits, it is responsible for the inevitable cement leakage growing with more instrumented segments and volumes involved. This study aimed to compare the biomechanical performance of pedicle screws augmented on all segments with those augmented only on the cranial and caudal vertebrae selectively. METHODS: The finite element model of L3-S1 was modeled with the CT data of a healthy volunteer, the solid/fenestrated pedicle screws from micro-CT scans of physical screws, and bone cement from the CT scans of a postoperative patient with CAPSI. Three different augmented strategies for pedicle screws were taken into consideration: augmentation at each pedicle trajectory (Model A), selective augmentation at the cranial and caudal pedicle trajectories (Model B), and pedicle trajectories without augmentation (Model C). A total of six surgical models were constructed: Models A, B, and C were subdivided into double segmental fusion from L4 to S1 (Models A1, B1, and C1) and multi-segment fusion from L3 to S1 (Models A2, B2, and C2). The Range of motion (ROM), stress on the cage, and stress on the fixed segments were compared among the six models. RESULTS: The ROM at the fusion segments decreased in all instrumentation models. The ROMs of Model B and Model A are similar in each direction, while that of Model C is significantly larger. The differences in the ROMs between Model A and Model B were noted to be less than 0.1°. Compared with Models A1 and A2, the peak Von Mise stress on the cage-endplate interface and pedicle screws were slightly higher in Models B1 and B2. In contrast, the stress of Models C1 and C2 increased significantly. The compressive stress was concentrated in the screw head, the cranial and caudal screws, and rods. CONCLUSIONS: The selective augmentation of pedicle screws is capable of providing reliable stability in short-segment posterior fixation (2- or 3-level). It could be a potential optimal procedure to minimize the associated complications of CAPSI.

Biomechanical evaluation of four different posterior instrumentation techniques for single-level transforaminal lumbar interbody fusion: a finite element analysis.

This study aims to investigate the fixation strength of unilateral cortical bone trajectory screw fixation (UCBT) and UCBT with contralateral translaminar facet screw fixation (UCBT-TFS) by repeating the verification of three finite element models. Three healthy female models of the lumbosacral spine were constructed. For each of them, four transforaminal lumbar interbody fusion (TLIF) models with the following instruments were created: bilateral traditional trajectory pedicle screw fixation (TT), bilateral cortical bone trajectory screw fixation (CBT), UCBT, and UCBT-TFS. A 150-N compressive load with 10 N/m moments was applied to simulate flexion, extension, lateral bending, and axial rotation. The range of motion (ROM), the stress of the cages, and the stress of the posterior fixations were compared. TT and UCBT-TFS had a similar low ROM compared to the intact models, and CBT showed a higher ROM in lateral bending. UCBT resulted in the highest ROM under all loading conditions, especially in lateral bending (116% and 170% greater than TT in left bending and right bending). UCBT induced a significant increase in the peak stress of cages and instruments, followed by CBT and UCBT-TFS, and the lowest mean values were observed for TT. Among the four different fixation techniques, TT offered the highest fixation strength and lowest implant stress, followed by UCBT-TFS and CBT, while UCBT was the least stable and resulted in increased stress of the screws and cages. UCBT-TFS improved biomechanical stability and appeared to be a less invasive alternative in well-selected patients with single-level TLIF.

Influence of cement-augmented pedicle screws with different volumes of polymethylmethacrylate in osteoporotic lumbar vertebrae over the adjacent segments: a 3D finite element analysis.

BACKGROUND: Polymethylmethacrylate (PMMA) is commonly used for cement-augmented pedicle screw instrumentation (CAPSI) to improve the fixation stability and reduce the risk of screw loosening in the osteoporotic thoracolumbar spine. Biomechanical researches have shown that various dose of cement (1-3 ml) can be injected to enhance screw stability. To date, there have been no studies on the relationship between adjacent segment degeneration and the volume of PMMA. This study aimed to explore the influence of CAPSI with different volumes of PMMA in osteoporotic lumbar vertebrae over adjacent segments by using finite element analysis. METHODS: Seven different finite element models were reconstructed and simulated under different loading conditions, including (1) an intact model, (2) three single-level CAPSI models with different volumes of PMMA (1, 1.73, and 2.5 ml), and (3) three double-level CAPSI models with different volumes of PMMA (1, 1.73, and 2.5 ml). To improve the accuracy of the finite element analysis, the models of the injectable pedicle screw and bone cement were created by using a three-dimensional scanning machine and the CAPSI patient's CT data, respectively. The range of motion (ROM), the stress of intervertebral discs, and the stress of facet in the adjacent segment were comparatively analyzed among the different models. RESULTS: The ROMs of the different segments were compared with experimental data, with good agreement under the different load conditions (21.3°, 13.55°, 13.99°, and 6.11° in flexion, extension, bending, and rotation at L3-S1 level, respectively). Compared with the intact model, the ROM, disc stresses, and facet stress in adjacent segments were found to be higher in the six operative models. Otherwise, with a larger volume of PMMA injected, the ROM, disc stresses, and facet stress slightly increased at the adjacent segment. However, the differences were insignificant with the biggest difference less than 3.8%. CONCLUSIONS: CAPSI could increase the incidence of disk degeneration in the adjacent segment, while within a certain range, different volumes of PMMA provided an approximate impact over the adjacent segment degeneration.

Deciphering the underlying mechanism of Xianlinggubao capsule against osteoporosis by network pharmacology.

BACKGROUND: Xianlinggubao formula (XLGB), a Chinese State Food and Drug Administration-permitted traditional Chinese herbal medicine, has been extensively used to treat osteoporosis. Although XLGB was shown to improve bone mass in ovariectomized rats and clinically alleviate osteoporosis symptoms, its pharmacological mechanisms remain unclear. METHODS: In this study, we used a network pharmacological approach to explore the potential mechanism of XLGB in treating osteoporosis. We obtained XLGB compounds from the TCMSP and TCMID databases and identified potential targets of these compounds through target fishing based on the TCMSP and Swiss Target Prediction databases. Next, we identified the osteoporosis targets by using the CTD, TTD, GeneCards, OMIM and PharmGKB databases. Then, the overlapping genes between the XLGB potential targets and the osteoporosis targets were used to establish a protein-protein interaction (PPI) network and to analyze their interactions and identify the major hub genes in this network. Subsequently, the Metascape database was utilized to conduct the enrichment of Gene Ontology biological processes and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. RESULTS: There were 104 active compounds and 295 related targets identified overall. After the Metascape enrichment analysis, we identified the top 25 cellular biological processes and top 15 pathways based on the logP value and found that the XLGB-mediated anti-osteoporosis effect was mainly associated with reactive oxygen species, organonitrogen compound response and cell migration. Furthermore, 36 hub genes of XLGB, such as EGF, EGFR, MTOR, MAPK14 and NFKB1, were considered potential therapeutic targets, suggesting the underlying mechanisms of XLGB acting on osteoporosis. CONCLUSION: We investigated the possible therapeutic mechanisms of XLGB from a systemic perspective. These key targets and pathways provide promising directions for future research to reveal the exact regulatory mechanisms of XLGB.