Search

Objective To investigate the use of anti‐osteoporotic agents and refracture incidence in patients with osteoporotic vertebral compression fracture (OVCF) following percutaneous vertebral augmentation (PVA) and to evaluate the real‐world treatment of patients using denosumab following PVA. This study aims to provide spine surgeons with empirical insights derived from real‐world scenarios to enhance the management of bone health in OVCF patients. Methods This retrospective cohort study was based on data from the MarketScan and Optum databases from the USA. Female patients aged 55–90 years who underwent PVA for OVCF between January 2013 and March 2020 were included and followed up from the day after surgery. Patients who received at least one dose of denosumab were included in the denosumab cohort and were further divided into the on‐treatment and off‐treatment groups according to whether they received a second dose of denosumab, with follow‐up beginning on the index day (225 days after the first denosumab dose). In this study, the off‐treatment group was considered as the control group. Refracture incidence after PVA, the proportion of patients using anti‐osteoporotic agents in the total study population, and refracture incidence after the index day in the denosumab cohort were analyzed. Results A total of 13,451 and 21,420 patients from the MarketScan and Optum databases, respectively, were included. In the denosumab cohort, the cumulative incidence of clinical osteoporotic fractures within 3 years after the index day was significantly lower in the on‐treatment group than in the off‐treatment group (MarketScan database: 23.0% vs 39.0%, p = 0.002; Optum database: 28.2% vs 40.0%, p = 0.023). The cumulative incidence of clinical vertebral fractures was also lower in the on‐treatment group than in the off‐treatment group, with a significant difference in the MarketScan database (14.4% vs 25.5%, p = 0.002) and a numerical difference was found in the Optum database (20.2% vs 27.5%, p = 0.084).The proportion of patients using anti‐osteoporotic agents was low at 6 months postoperatively, with only approximately 7% using denosumab and 13%–15% taking oral bisphosphonates. Conclusion Postmenopausal women have a high refracture rate and a low proportion of anti‐osteoporotic drug use after PVA. Continued denosumab treatment after PVA is associated with a lower risk of osteoporotic and clinical vertebral fractures. Therefore, denosumab may be a treatment option for patients with osteoporosis after PVA.

Abstract Background Thoracolumbar fascia injury (FI) is rarely discussed in osteoporotic vertebral fracture (OVF) patients in previous literature and it is usually neglected and treated as an unmeaning phenomenon. We aimed to evaluate the characteristics of the thoracolumbar fascia injury and further discuss its clinical significance in the treatment of kyphoplasty for osteoporotic vertebral fracture (OVF) patients. Methods Based on the presence or absence of FI, 223 OVF patients were divided into two groups. The demographics of patients with and without FI were compared. The visual analogue scale and Oswestry disability index scores were compared preoperatively and after PKP treatment between these groups. Results Thoracolumbar fascia injuries were observed in 27.8% of patients. Most FI showed a multi-level distribution pattern which involved a mean of 3.3 levels. Location of fractures, severity of fractures and severity of trauma were significantly different between patients with and without FI. In further comparison, severity of trauma was significantly different between patients with severe and non-severe FI. In patients with FI, VAS and ODI scores of 3 days and 1 month after PKP treatment were significantly worse compared to those without FI. It showed the same trend in VAS and ODI scores in patients with severe FI when compared to those patients with non-severe FI. Conclusions FI is not rare in OVF patients and presents multiple levels of involvement. The more serious trauma suffered, the more severe thoracolumbar fascia injury presented. The presence of FI which was related to residual acute back pain significantly affected the effectiveness of PKP in treating OVFs. Trial registration retrospectively registered.

In ecological stoichiometry, the stoichiometry and spatial distribution of leaf carbon, nitrogen, and phosphorus are important research topics. Various studies have assessed leaf stoichiometry and its relationships with environmental factors at different scales. However, how the leaf carbon, nitrogen and phosphorus stoichiometric characteristics of the same vegetation type at the community level vary with environmental factors along a continuous altitudinal gradient remains poorly understood. In this paper, 13 sampling sites along an altitudinal gradient of 1,800—3,011 m in a typical temperate mountain meadow ecosystem on the southern slope of the Wutai Mountain in North China were sampled to explore the response of leaf carbon, nitrogen and phosphorus stoichiometric characteristics to altitude change using correlation analysis, and then quantified the contribution of driving factors using canonical correspondence analysis (CCA) and variation partitioning. We found that the community-level leaf stoichiometry of mountain meadows differed significantly at different altitudes, and an increase in altitude significantly decreased community-level leaf total nitrogen (LTN) and leaf total phosphorus (LTP); however, the leaf total carbon (LTC), C∶N, C∶P, and N∶P increased with an increase in altitude. Additionally, with increasing altitude, soil properties showed significant trends. Soil organic carbon (SOC), soil total nitrogen (STN), soil total phosphorus (STP), soil water content and soil electrical conductivity increased significantly, but soil temperature, soil bulk density and soil pH exhibited the opposite trend. Our results suggested that altitude, soil electrical conductivity and soil bulk density significantly influenced the changes in the leaf stoichiometric characteristics, explaining 75.5% of the total variation, and altitude had the greatest influence (36.6%). In the temperate mountains, altitude played a decisive role in affecting patterns of meadow plant nutrients and stoichiometry and was more important than soil in explaining leaf C∶N∶P stoichiometry variations. Our findings provide important references to understand the responses of plant stoichiometry to altitudinal gradients.

Exploring future land use/cover change (LULC) and ecosystem service values (ESV) dynamics is crucial for sustainable development from regional to global scales. However, ESV dynamics is significantly affected by economic development and policy changes, and future projections of ESV are generally characterized by large uncertainties due to complexity in LULC dynamics. Mining activities are supposed to exert significant effects on ESV dynamics, while the patterns and controls of ESV in mining-dominated basins are still less understood, especially under different land-use scenarios. Here, based on multi-source remote sensing data and land-use data in the Fenhe River Basin, we integrated the SD model, Markov model and PLUS model to simulate LULC in the Fenhe River Basin under four scenarios, i.e., the economic development priority (EDP), natural development priority (ND), cultivated land protection priority (CLP), and ecological protection priority (EPP). Based on ESV equivalent coefficient method and geographical detector, we further determined the patterns and controls of ESV. Results showed that construction land and cultivated land were mainly concentrated in the central parts of the basin, and grassland and woodland were concentrated in the edge area of the basin. Over the past two decades, construction land and woodland have experienced significant expansion, while the areas of grasslands and cultivated lands have declined due to mining activities. The high-value and sub-high-value areas of ESV were concentrated in woodland, grassland, reservoir and concentrated water area of mainstream and tributary. The low-value area was mainly located in the gathering area of construction land. The total ESV showed a downward trend with time, and the highest decline in the total ESV under the four land use scenarios was the EDP, while the lowest drop was the EPP. The highest contribution rate of ESV was woodland, which was equivalent to the contribution rate of cultivated land, grassland and water area, totally accounting for 58.54% of the whole ESV. The geographical detector method indicated that distance to the residential area, soil erodibility, distance to the river, soil type and annual average temperature were the main driving factors affecting the spatial patterns of ESV. Our results highlighted the fundamental role of mining activity in affecting LULC characterized by grassland and cultivated land shrinkage, and suggested that mining areas rehabilitation should be given priority in terms of further improving ESV in mining-dominated basins.

Upon the osteoporotic condition, sluggish osteogenesis, excessive bone resorption, and chronic inflammation make the osseointegration of bioinert titanium (Ti) implants with surrounding bone tissues difficult, often lead to prosthesis loosening, bone collapse, and implant failure. In this study, we firstly designed clickable mussel-inspired peptides (DOPA-N3) and grafted them onto the surfaces of Ti materials through robust catechol-TiO2 coordinative interactions. Then, two dibenzylcyclooctyne (DBCO)-capped bioactive peptides RGD and BMP-2 bioactive domain (BMP-2) were clicked onto the DOPA-N3-coated Ti material surfaces via bio-orthogonal reaction. We characterized the surface morphology and biocompatibility of the Ti substrates and optimized the osteogenic capacity of Ti surfaces through adjusting the ideal ratios of BMP-2/RGD at 3:1. In vitro, the dual-functionalized Ti substrates exhibited excellent promotion on adhesion and osteogenesis of mesenchymal stem cells (MSCs), and conspicuous immunopolarization-regulation to shift macrophages to alternative (M2) phenotypes and inhibit inflammation, as well as enhancement of osseointegration and mechanical stability in osteoporotic rats. In summary, our biomimetic surface modification strategy by bio-orthogonal reaction provided a convenient and feasible method to resolve the bioinertia and clinical complications of Ti-based implants, which was conducive to the long-term success of Ti implants, especially in the osteoporotic or inflammatory conditions.

The periosteum on the skeletal surface creates a unique micro-environment for cortical bone homeostasis, but how this micro-environment is formed remains a mystery. In our study, we observed the cells in the periosteum presented elongated spindle-like morphology within the aligned collagen fibers, which is in accordance with the differentiated osteoblasts lining on the cortical surface. We planted the bone marrow stromal cells(BMSCs), the regular shaped progenitor cells, on collagen-coated aligned fibers, presenting similar cell morphology as observed in the natural periosteum. The aligned collagen topology induced the elongation of BMSCs, whichfacilitated the osteogenic process. Transcriptome analysis suggested the aligned collagen induced the regular shaped cells to present part of the periosteum derived stromal cells(PDSCs) characteristics by showing close correlation of the two cell populations. In addition, the elevated expression of PDSCs markers in the cells grown on the aligned collagen-coated fibers further indicated the function of periosteal topology in manipulating cells’ behavior. Enrichment analysis revealed cell-extracellular matrix interaction was the major pathway initiating this process, which created an osteo-friendly micro-environment as well. At last, we found the aligned topology of collagen induced mechano-growth factor expression as the result of Igf1 alternative splicing, guiding the progenitor cells behavior and osteogenic process in the periosteum. This study uncovers the key role of the aligned topology of collagen in the periosteum and explains the mechanism in creating the periosteal micro-environment, which gives the inspiration for artificial periosteum design.

Evaluating the nitrogen (N) use efficiency of animal manure is essential to optimize its application for profitable crop production without impairing the environment. A four-year field study was conducted under corn (Zea mays L.)–soybean (Glycine max L.) rotation in a Brookston clay loam soil using the yield control approach. Treatments included inorganic fertilizer (IN), and liquid (LM), solid (SM), and composted (CM) swine manure applied at the rate equivalent to an available N of 200 kg ha−1 and a non-fertilization control (CT). Seven N use indices were employed to evaluate N use efficiency. LM obtained comparable corn yields relative to IN. Corn yield in SM was inconsistent from one year to another, and CM had minimal agronomical value in our study. Soybeans with IN posed the highest grain yields of 3,468 and 3,761 kg ha−1 in 2005 and 2007, respectively. In contrast to grain yield and total N uptake, the gain N removal of either corn or soybeans was comparable between the two alternative years. The distinctions between N supply dynamics of manures and their influences on yield, grain N removal, and total above-ground plant N uptake of corn were well discriminated by N use efficiency (NUE), N uptake efficiency (NUpE), N utilization efficiency (NUtE), N agronomic efficiency (NAE), and N recovery efficiency (NRE), but not by N physiological efficiency (NPE) and N harvest index (NHI). Legacy effects on soybean yield from the preceding corn were detected by NAE and NRE. Based on grain yield in conjunction with N use efficiency parameters, the IN performed the best, followed by LM. The NUE, NUpE, NUtE, NAE, and NRE parameters used to evaluate chemical fertilizer N were also applicable to evaluate manure N efficiency.

PurposeTo assess the efficacy and complications of anterior cervical discectomy and fusion (ACDF) with ROI-C device vs. conventional anterior plate and cage system (APCS) in managing traumatic central cord syndrome (TCCS).MethodsA total of 37 patients diagnosed with TCCS who underwent ACDF with ROI-C implant and APCS were recruited in this retrospective study from June 2012 to February 2020. Radiological parameters and clinical results were recorded and compared through follow-up time. Characteristics of patients and complications were also recorded.ResultsAll patients tolerated the procedure well. The average follow-up time was 25.00 ± 7.99 months in the ROI-C group, and 21.29 ± 7.41 months in the APCS group. The blood loss and operation time were significantly lower in the ROI-C group than in the APCS group. Radiological parameters and clinical results were all improved postoperatively and maintained at the final follow-up. Fusion was achieved in all patients. ROI-C group had a lower incidence of postoperative dysphagia than the APCS group. Only 1 case of ALD was observed at the final follow-up in the APCS group.ConclusionsBoth ROI-C device and APCS demonstrated satisfactory clinical effects and safety in managing symptomatic single-level traumatic central cord syndrome with underlying instability. Both techniques could improve and maintain cervical lordosis and disc height. ROI-C device was related to a lower incidence of postoperative dysphagia, shorter operation time, and less blood loss.

BackgroundOur study is to determine the correlation between preoperative MRI parameters of spinal cord compression and the effects of anterior surgery in patients with degenerative cervical myelopathy (DCM).Methods24 normal subjects with no evident abnormalities were selected as group A. 79 patients with DCM underwent single-segment (C4–5/C5–6) ACDF surgery formed the operation group, and separated into group B (without high signal) and group C (with high signal) according to the absence or presence of high signal in the spinal cord on preoperative T2-weighted MRI respectively. MRI parameters (MCC, maximum canal compromise; MSCC, maximum spinal cord compression; CR, spinal cord compression rate; RCSCDS, ratio of cervical spinal cord to dura sac) were measured. The JOA score was used to evaluate cervical spinal cord function and recovery rate (RR) was used to evaluate postoperative efficacy. The relationship between preoperative MRI parameters and postoperative efficacy was analyzed.ResultsThe preoperative JOA score and RR of group B were higher than that of group C. MCC and MSCC in group B were significantly lower than those in groups C. The multiple linear regression equation was the fitted postoperative JOA score = 13.371–2.940 * MCC −5.660 * RCSCDS +0.471 * preoperative JOA score. The fitted RR = 1.451–0.472 * MCC −1.313 * RCSCDS.ConclusionThe occurrence of high signal on T2-weighted images could reflect more serious spinal cord injury. The postoperative JOA score was significantly correlated with MCC, RCSCDS, and preoperative JOA score, while RR was significantly associated with MCC and RCSCDS.

Coronavirus disease 2019 (COVID-19) outbreak started in December 2019 that caused difficulties for clinical work. Practical work experience in our spinal outpatient and emergency department during the COVID-19 pandemic is summarized in this article, with combined evidence-based medical evidence to explore a standardized process of diagnosis and treatment for spinal diseases. Outpatient reservation, continuous screening, triage, and isolation, first consultation accountability system, pandemic reporting system, and online revisit were strictly followed. We hope that our experience in prevention and control of COVID-19 can help spine surgeons globally in stopping the spread of COVID-19. Spine surgeons should collaborate with infection control specialists to avoid cross-infection in hospitals and optimize treatment.

BackgroundSpinal cord ischemia is largely caused by cervical spondylotic myelopathy (CSM), which has a corresponding biomechanical basis. Finite element analysis of spinal cord stress in diseased segments of CSM was performed to provide a biomechanical basis for the pathogenesis of CSM.MethodsA single segment (C4-5) in a patient with CSM was selected for mechanical simulation of three-dimensional (3D) computed tomography scanning, and a 3D finite element model of the cervical vertebra was constructed. Based on the patient's age, sex, height, weight, and other parameters, a finite element analysis model of an individual with healthy cervical vertebrae in our hospital was selected as the control to compare the stress changes between the patient and control groups in the analysis of the cervical vertebrae under anterior flexion, posterior extension, lateral flexion, and rotating load in the diseased spinal cord segment.ResultsIn the CSM patient, the diseased segment was C4-5. Under loading conditions of forward flexion, posterior extension, left flexion, right flexion, left rotation, and right rotation, the maximum stress on the spinal cord in the control group was 0.0044, 0.0031, 0.00017, 0.00014, 0.0011, and 0.001 MPa, respectively, whereas those in the spinal cord in the CSM group were 0.039, 0.024, 0.02, 0.02, 0.0194, and 0.0196 MPa, respectively.ConclusionThe maximum stress on the diseased segments of the spinal cord in the CSM group was higher than that in the control group, which contributed to verifying the imaging parameters associated with spinal cord compression stress.

Summary: The Li+/Ni2+ mixing in LiNi0.8Mn0.1Co0.1O2 (NMC811) leads to fast battery capacity decay. Here we report a dual-gradient nickel-rich layered cathode material (D-NMC811), using nickel-based metal organic framework of Ni-MOF-74. The formation of a protective layer with rock salt phase due to the reduced nickel oxidation state on the surface of the primary particles resists internal strain and suppresses further phase transition, thus alleviating crack generation. After 300 cycles at ⅓ C, a high half-cell capacity retention of 88.50% with 0.038% decay per cycle is observed. The full-cell battery displays a high capacity retention of >86.7% with a Coulombic efficiency of >99.86% at ⅓ C after 300 cycles. The 300 mAh pouch cell delivers an energy density of 216.4 Wh/kg. After 500 cycles at 1.0 C, it still displays 84.1% capacity retention while the battery with conventional NMC811 only shows a retention of 53.0% after 400 cycles.

Steroid-induced osteonecrosis of the femoral head (SONFH) is a disease characterized by the collapse of the femoral head. SONFH occurs due to the overuse of glucocorticoids (GCs) in patients with immune-related diseases. Among various pathogenesis proposed, the mechanism related to impaired blood vessels is gradually becoming the most convincing hypothesis. Bone endothelial cells including bone microvascular endothelial cells (BMECs) and endothelial progenitor cells (EPCs) play a crucial role in the maintenance of vascular homeostasis. Therefore, bone endothelial cells are key regulators in the occurrence and progression of SONFH. Impaired angiogenesis, abnormal apoptosis, thrombosis and fat embolism caused by the dysfunctions of bone endothelial cells are considered to be the pathogenesis of SONFH. In addition, even with high disability rates, SONFH lacks effective therapeutic approach. Icariin (ICA, a flavonoid extracted from Epimedii Herba), pravastatin, and VO-OHpic (a potent inhibitor of PTEN) are candidate reagents to prevent and treat SONFH through improving above pathological processes. However, these reagents are still in the preclinical stage and will not be widely used temporarily. In this case, bone tissue engineering represented by co-transplantation of bone endothelial cells and bone marrow mesenchymal stem cells (BMSCs) may be another feasible therapeutic strategy.

Abstract Background Degenerative intervertebral disc (IVD) disease can cause lower back pain. However, the change of lactic acid content during disc degeneration process still unclear. The objective of this study was to investigate whether the change of the content of lactic acid is associated with depletion of degenerative intervertebral disc extracellular matrix. Methods A total of 18 miniature pigs were equally divided into annular lesion surgery (AL) and sham group. The lateral superficial annulus fibrosus (AF) of T12-L4 discs in AL group were penetrated by 3.5 mm trepan with the depth of 3 mm, the same IVD were only exposed without any injury in the sham group. At 4, 8 and 12 weeks after surgery, the degree of intervertebral disc degeneration was evaluated by magnetic resonance, histological and biochemical analysis. Results No obvious degeneration was found in sham group. However, disc degeneration was found and gradually worsened in AL group after surgery. Histological analysis showed that the AF was rupture and disorder, the number of cells in nucleus pulposus (NP) was decreased in AL group. Compared with the sham group, the extent of type II collagen (Col-II) and aggrecan in NP tissue was dramatically decreased in AL group, consistent with the results of Col -II immunohistochemistry staining and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Besides, the gene expression of matrix metallopeptidase 3 and 13 also continuous increased in AL group. The amount of lactic acid and nerve growth factor in NP tissue was gradually increased after operation in AL group. Conclusions The content of lactic acid gradually increased after annular lesion, associated with the damage of AF structural and the decrease of Col -II and aggrecan in NP tissue, which leading to the disc degeneration. Depletion of extracellular matrix is consistent with lactic acid accumulation inside of IVD.

Background: Percutaneous kyphoplasty (PKP), a minimally invasive treatment, has been widely used for osteoporotic vertebral compression fractures (OVCFs). Objective: To retrospectively analyse the therapeutic effects of PKP using a series of key techniques in a multicentre study. Methods: From May 2000 to December 2016, PKP was performed using a series of key techniques (puncture, reduction, and perfusion techniques) for the treatment of 4532 OVCF patients. The pain visual analog scale (VAS) and the Oswestry Disability Index (ODI) questionnaire prior to the operation, at postoperative Day 2, and at the last follow-up were analysed by paired t-test analysis. The leakage of bone cement was evaluated by postoperative radiography and/or computed tomography. Four-year survival was calculated at the last follow-up. Results: The average follow-up was 63 months (1–116 months). The VAS score decreased from 8.9 (preoperative) to 2.3 (2 days postoperative) to 1.9 (last follow-up). The ODI score of the patients decreased from 86.7 (preoperative) to 31.6 (2 days postoperative) to 25.3 (last follow-up). Both VAS score and ODI score improved significantly. The bone cement leakage rate was 3.5%, with no clinical symptoms. The 4-year survival rate was 77.5%. Conclusion: This study suggests that PKP with key techniques would be an effective technique to treat OVCF with less risk and better therapeutic effect. Such diagnostic methods and surgical techniques lead to the development and progress of treatment for OVCF. The translational potential of this article: PKP with key techniques would be an effective technique to treat and lead to the development and progress of treatment for OVCF.

Abstract Alloy-type anodes such as silicon and tin are gaining popularity in rechargeable Li-ion batteries, but their rate/cycling capabilities should be improved. Here by making yolk-shell nanocomposite of aluminium core (30 nm in diameter) and TiO2 shell (∼3 nm in thickness), with a tunable interspace, we achieve 10 C charge/discharge rate with reversible capacity exceeding 650 mAh g−1 after 500 cycles, with a 3 mg cm−2 loading. At 1 C, the capacity is approximately 1,200 mAh g−1 after 500 cycles. Our one-pot synthesis route is simple and industrially scalable. This result may reverse the lagging status of aluminium among high-theoretical-capacity anodes.

Nature Communications 6: Article number: 7872 (2015); Published 5 August 2015; Updated 29 November 2017 This Article contains an error in which the scanning electron microscope image shown in Fig. 2b was included incorrectly. The original Fig. 2b showed yolk-shell microstructures, as previously published in Li, S.

In ecological stoichiometry, the stoichiometry and spatial distribution of leaf carbon, nitrogen, and phosphorus are important research topics. Various studies have assessed leaf stoichiometry and its relationships with environmental factors at different scales. However, how the leaf carbon, nitrogen and phosphorus stoichiometric characteristics of the same vegetation type at the community level vary with environmental factors along a continuous altitudinal gradient remains poorly understood. In this paper, 13 sampling sites along an altitudinal gradient of 1,800--3,011 m in a typical temperate mountain meadow ecosystem on the southern slope of the Wutai Mountain in North China were sampled to explore the response of leaf carbon, nitrogen and phosphorus stoichiometric characteristics to altitude change using correlation analysis, and then quantified the contribution of driving factors using canonical correspondence analysis (CCA) and variation partitioning. We found that the community-level leaf stoichiometry of mountain meadows differed significantly at different altitudes, and an increase in altitude significantly decreased community-level leaf total nitrogen (LTN) and leaf total phosphorus (LTP); however, the leaf total carbon (LTC), CN, C-P, and N-P increased with an increase in altitude. Additionally, with increasing altitude, soil properties showed significant trends. Soil organic carbon (SOC), soil total nitrogen (STN), soil total phosphorus (STP), soil water content and soil electrical conductivity increased significantly, but soil temperature, soil bulk density and soil pH exhibited the opposite trend. Our results suggested that altitude, soil electrical conductivity and soil bulk density significantly influenced the changes in the leaf stoichiometric characteristics, explaining 75.5% of the total variation, and altitude had the greatest influence (36.6%). In the temperate mountains, altitude played a decisive role in affecting patterns of meadow plant nutrients and stoichiometry and was more important than soil in explaining leaf C-N-P stoichiometry variations. Our findings provide important references to understand the responses of plant stoichiometry to altitudinal gradients. [ABSTRACT FROM AUTHOR]