Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 133
Filtrar
1.
Adv Mater ; : e2403164, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720548

RESUMO

Surface reconstruction, reorganizing the surface atoms or structure, is a promising strategy to manipulate materials' electrical, electrochemical, and surface catalytic properties. Herein, a rapid surface reconstruction of indium sulfide (In2S3) is demonstrated via a high-temperature flame treatment to improve its charge collection properties. The flame process selectively transforms the In2S3 surface into a diffusionless In2O3 layer with high crystallinity. Additionally, it controllably generates bulk sulfur vacancies within a few seconds, leading to surface-reconstructed In2S3 (sr-In2S3). When using those sr-In2S3 as photoanode for photoelectrochemical water splitting devices, these dual functions of surface In2O3/bulk In2S3 reduce the charge recombination in the surface and bulk region, thus improving photocurrent density and stability. With optimized surface reconstruction, the sr-In2S3 photoanode demonstrates a significant photocurrent density of 8.5 mA cm-2 at 1.23 V versus a reversible hydrogen electrode (RHE), marking a 2.5-fold increase compared to pristine In2S3 (3.5 mA cm-2). More importantly, the sr-In2S3 photoanode exhibits an impressive photocurrent density of 7.3 mA cm-2 at 0.6 V versus RHE for iodide oxidation reaction. A practical and scalable surface reconstruction is also showcased via flame treatment. This work provides new insights for surface reconstruction engineering in sulfide-based semiconductors, making a breakthrough in developing efficient solar-fuel energy devices.

2.
Nanotechnology ; 35(16)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38198719

RESUMO

Controlling and preventing Cu oxidation is crucial for improving the performance and reliability of Cu-Cu bonding. Ni-B films were selectively deposited on Cu films to block the Cu oxidation. The resistivity changes of the Cu films in N2and O2ambient were measured by using a four-point probe in thein situtemperature-dependent resistance measurements at the temperature from room temperature to 400 °C. The resistivity changes of the 100 nm thick Cu films without Ni-B increased rapidly at a higher temperature (284 °C) in the O2ambiance. The change of resistivity-increase of 100 nm thick Cu with ∼50 nm thick Ni-B (top) film was lower than the Cu films without Ni-B films due to the blocking diffusion of O2atoms by the Ni-B films. The resistivity-change and oxidation barrier properties were studied using scanning electron microscopy, FIB, transmission electron microscopy, EDX, and secondary ion mass spectroscopy tools. The proposed article will be helpful for the upcoming advancement in Cu-Cu bonding using selected-area deposition.

3.
Int J Biol Macromol ; 254(Pt 3): 127236, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37797861

RESUMO

This study investigated the impact of cellulose nanofibers (CNFs) on montmorillonites (MMTs) exfoliation within thermoplastic starch (TPS) nanocomposites during the melt blending process. TPS nanocomposite films were manufactured using an internal mixer with a controlled ratio of CNFs and MMTs to evaluate the effect of individual and hybrid fillers on the material interactions and characteristics of the TPS composites. The incorporation of hybrid fillers resulted in notable enhancements in torque values and rheological properties, suggesting interactions between the starch, CNFs, and MMTs. The degree of MMT intercalation, obtained via X-ray diffraction analysis, decreased with the addition of CNFs, indicating that CNFs positively impacted MMT exfoliation. Scanning electron microscopy (SEM) images of cryo- and tensile-fractured samples highlighted the effectiveness of CNFs in facilitating MMT exfoliation and reinforcing interactions between the MMTs and TPS matrix. These interactions enhanced the tensile strength and Young's modulus by up to 95.8 % and 278.2 %, respectively, with a 1:1 weight ratio of CNFs to MMTs. Additionally, well-dispersed MMTs within the TPS matrix caused passivation and created tortuous paths, improving the water contact angle and decreasing the water vapor sorption. These synergistic effects of the hybrid filler, achieved through a melt blending process, indicate the potential use of TPS nanocomposites as an eco-friendly packaging material.


Assuntos
Nanocompostos , Nanofibras , Amido , Celulose , Bentonita , Excipientes , Resistência à Tração
4.
Nanomaterials (Basel) ; 13(19)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37836283

RESUMO

Photosensitive polyimides (PSPIs) have been widely developed in microelectronics, which is due to their excellent thermal properties and reasonable dielectric properties and can be directly patterned to simplify the processing steps. In this study, 3 µm~7 µm thick PSPI films were deposited on different substrates, including Si, 50 nm SiN, 50 nm SiO2, 100 nm Cu, and 100 nm Al, for the optimization of the process of integration with Cu films. In situ temperature-dependent resistance measurements were conducted by using a four-point probe system to study the changes in resistance of the 70 nm thick Cu films on different dielectrics with thick diffusion films of 30 nm Mn, Co, and W films in a N2 ambient. The lowest possible change in thickness due to annealing at the higher temperature ranges of 325 °C to 375 °C is displayed, which suggests the high stability of PSPI. The PSPI films show good adhesion with each Cu diffusion barrier up to 350 °C, and we believe that this will be helpful for new packaging applications, such as a 3D IC with a Cu interconnect.

5.
Food Sci Anim Resour ; 43(3): 512-530, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37181220

RESUMO

The present study evaluated the effects of fermented whey protein using kimchi lactic acid bacteria Lactobacillus casei DK211 on skeletal muscle mass, muscle strength, and physical performance in healthy middle-aged males performing regular resistance exercises. Effective protein supplementation and regular exercise are two important factors for improving muscle health. Therefore, in this study, the effects of consuming fermented whey protein twice a day were investigated and compared with that of non-fermented supplementation. Forty-eight males (average age 44.8) were randomly assigned to two groups: Fermented whey protein supplementation (FWPS) and non-fermented whey protein concentration supplementation (WPCS) groups. Each group ingested 37 g of FWPS or WPCS twice a day for eight weeks. Body composition, muscle strength, and physical performance were assessed pre- and post-intervention. Independent t-tests or chi-square tests for the categorical variables were performed for analyzing the observations. FWPS was effective in promoting the physical performance in dynamic balance measurement and muscle health, indicated through the increment in grip strength (left), upper arm circumference, and flat leg circumference from the baseline. However, similar improvements were not observed in the WPCS group. These results imply that whey protein fermented by L. casei DK211 is an effective protein supplement for enhancing muscle health in males performing regular resistance exercises.

6.
Sci Rep ; 13(1): 8786, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37258690

RESUMO

The 3D display device shows an image with depth information. Conventional 3D display devices based on binocular parallax can focus accurately only on the depth of a specific screen. Because the human eye has a narrow depth of field (DOF) under normal circumstances, 3D displays that provide a relatively wide range of virtual depth areas have limitations on the DOF where clear 3D images are seen. To resolve this problem, it is necessary to find the optical conditions to extend the DOF and analyze the phenomena related to it. For this, by using the Rayleigh criterion and the Strehl ratio, a criterion for this extension of the DOF is suggested. A practical optical structure that can effectively extend the DOF is devised using a flat panel display. This optical structure could be applied to AR, VR, and MR in the field of near-eye displays. From the results of this research, the fundamental optical conditions and standards are proposed for 3D displays that will provide 3D images with extended DOF in the future. Furthermore, it is also expected that these conditions and criteria can be applied to optical designs for the required performance in the development of 3D displays in various fields.

7.
Front Pharmacol ; 14: 1114410, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36998613

RESUMO

Objectives: This study aimed to evaluate the clinical efficacy and safety of PE extracts developed for the purpose of relieving pain and improving knee joint function on semi-healthy people with mild knee joint pain. Methods: A randomized, double-blind, two-arm, single-center, placebo-controlled clinical trial was conducted. Individuals with knee joint pain and a visual analogue scale (VAS) score < 50 mm were included in the study, and participants with radiological arthritis were excluded. Participants were administered either PFE or a placebo capsule (700 mg, twice a day) orally for eight weeks. The comparisons of the changed VAS score and Western Ontario and McMaster Universities Osteoarthritis (WOMAC) scores between the PFE and placebo groups were primary outcomes, while the five inflammation-related laboratory tests including cartilage oligomeric matrix protein, cyclooxygenase-2, neutrophil and lymphocyte ratio, high sensitive C-reactive protein, and erythrocyte sedimentation rate were secondary outcomes. Also, a safety assessment was done. Results: Eighty participants (mean age, 38.4 ± 14.0, male: female, 28:52) were enrolled; 75 completed the trial (PFE 36 and placebo 39). After eight weeks, both VAS and WOMAC scores were reduced in the PFE and placebo groups. The changed scores were significantly higher in the PFE group compared to the placebo group: 19.6 ± 10.9 vs. 6.8 ± 10.5; VAS scores (p < 0.001), and 20.5 ± 14.7 vs. 9.3 ± 16.5; total WOMAC scores (p < 0.01) including the sub-scores for pain, stiffness, and functions. No significant changes were reported in the five inflammation-related laboratory parameters. All adverse events were considered minor and unlikely to result from the intervention. Conclusion: Eight weeks of PFE intake was more effective than placebo in reducing knee joint pain and improving knee joint function in sub-healthy people with mild knee joint pain, and there were no major safety concerns. Clinical Trial Registration: https://cris.nih.go.kr/cris/search/detailSearch.do?search_lang=E&focus=reset_12&search_page=M&pageSize=10&page=undefined&seq=23101&status=5&seq_group=19745, identifier CRIS: KCT0007219.

8.
Molecules ; 27(22)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36431883

RESUMO

Ulcerative colitis is an inflammatory bowel disease characterized by symptoms such as abdominal pain, diarrhea, bleeding, and weight loss. Ulcerative colitis is typically treated with anti-inflammatory drugs; however, these drugs are associated with various side effects, limiting their use. ß-Caryophyllene (BCP), a natural compound derived from cloves, has antioxidant, antibacterial, and anti-inflammatory activities. In this study, we aimed to investigate the effects of BCP on colitis in a dextran sulfate sodium (DSS)-induced colitis mouse model. BCP was administered for seven days, followed by 2.5% DSS for additional seven days to induce colitis. Changes in stool weight, recovery of gut motility, colon length, colon histology, myeloperoxidase activity, inflammatory cytokines (TNF-α, IL-1ß, IL-6, IgA, and IgG), and the gut microbiota were observed. Administration of BCP increased stool weight, restored gut motility, and considerably increased colon length compared to those in the untreated colitis mouse model. In addition, the amount of mucin and myeloperoxidase activity in the colon increased, whereas the concentrations of IL-1ß, IL-6, and TNF-α decreased following the administration of BCP. Furthermore, BCP reduced the abundance of Proteobacteria which can cause intestinal immune imbalance. These results suggest that BCP has a potential to be developed as a preventive agent for colitis.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Syzygium , Camundongos , Animais , Sulfato de Dextrana/efeitos adversos , Colite Ulcerativa/tratamento farmacológico , Fator de Necrose Tumoral alfa/farmacologia , Interleucina-6/farmacologia , Peroxidase , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/patologia , Inflamação/tratamento farmacológico , Modelos Animais de Doenças , Anti-Inflamatórios/uso terapêutico
10.
J Clin Med ; 11(8)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35456302

RESUMO

Primary cervical spine infections progress quickly and cause neurological impairment at an early stage. Despite their clinical significance, few studies have investigated primary cervical spine infections, owing to the rarity of the condition. This study analyzed the characteristics of 59 patients treated for primary cervical spine infections between 1992 and 2018 at our hospital. Clinical and radiological analyses were conducted. Moreover, a comparative analysis was performed, incorporating each patient's underlying disease, mortality and complications, and treatment results. Comparison between groups based on the chronological period (1992-2000, 2001-2009, and 2010-2018) revealed that the mean age of onset has increased significantly in recent years. The rate of neurological impairment, duration of antibiotic use, and frequency of underlying disease increased significantly with time. No significant differences among groups were observed in the hematological and microbiological analyses. The incidence rate of epidural abscess and multisegmental infection increased significantly in recent years. There was no statistically significant difference in the complication and mortality rates, according to the time period. We think that prompt diagnosis and appropriate treatment are necessary, considering the current trends in primary cervical spine infection.

11.
Food Chem Toxicol ; 161: 112847, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35143918

RESUMO

Although accumulation of amyloid ß (Aß) plaque is a major hallmark of Alzheimer's disease (AD), various pathologies have been suggested therapeutic targets. Therefore, therapies-targeting multiple pathologies would be required for effective managements of AD. Accordingly, natural products, which has multiple active ingredients, have been receiving a lot of attention. In this study, we tested whether standardized ethanol extract of leaves of Perilla frutescens var. acuta (L.) Britt. (Lamiaceae) (ELPF) could modulate various pathologies in AD using 5XFAD mice. ELPF blocked Aß aggregation and disassembled pre-formed Aß aggregates. ELPF blocked Aß aggregates-induced LTP impairment and ELPF-disassembled Aß aggregates failed to impair hippocampal LTP. Systemic administration of ELPF blocked Aß aggregates-induced memory impairment in a passive avoidance test. ELPF-disassembled Aß aggregates failed to impair passive avoidance memory. Prolonged administration of ELPF ameliorated memory impairments in 5XFAD mice. In the hippocampus of 5XFAD mice, ELPF administration significantly reduced Aß deposits and neuroinflammation. These results demonstrate that ELPF could be a promising therapeutic candidate for AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Perilla frutescens/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Animais , Feminino , Hipocampo/patologia , Masculino , Camundongos Transgênicos , Extratos Vegetais/química
12.
Orthop Surg ; 13(8): 2363-2372, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34791834

RESUMO

OBJECTIVE: To analyze characteristics of surgically managed tear drop (TD) fractures of the C2 axis associated with other injuries such as hangman's fracture and C2-3 discoligamentous injury as well as treatment outcomes. METHODS: A total of 14 patients (eight men and six women) with TD fractures of the C2 , who were surgically treated at four national trauma centers of tertiary university hospitals from January 2000 to December 2017, were included in this retrospective study. The mean age of the patients was 45.5 years (ranging from 19 to 74 years). The characteristics, surgical treatment methods (anterior fusion vs posterior fusion), and results of 14 TD fractures of the C2 were analyzed retrospectively. And the clinical relevance between C2 TD fracture and hangman's fracture and C2-3 discoligamentous injury was investigated through the co-occurrence between injuries. The mean follow-up time after surgery was 22.6 months (ranging from 12 to 60 months). RESULTS: Among 14 patients with TD fracture of the C2 , four patients (28.6%) had anterior TD fracture and 10 patients (71.4%) had posterior TD fracture. All 10 posterior TD fracture patients had anterior C2-3 displacement. While two of four anterior TD fracture patients had posterior C2-3 displacement, the remaining two did not. All 14 patients of TD fracture had at least two or more other associated C2 injuries as well as C2-3 discoligamentous injuries. About 92.9% (13/14) of the patients had typical or atypical hangman's fracture; 100% (10/10) of the posterior TD fracture patients had hangman's fracture, but 75% (3/4) of the anterior TD fracture had hangman's fracture. At admission, 13 patients were neurologically intact. However, the remaining patient had spinal cord injury with American Spinal Injury Association (ASIA) impairment scale B with C2-3 bilateral facet dislocation. All four anterior TD fracture patients underwent posterior C2-3 fusion. While four of 10 posterior TD fracture patients underwent C2-3 anterior fusion, the remaining six underwent posterior fusion. At last follow-up, 100% (14/14) of the patients achieved solid fusion, and visual analog scale for neck pain was significantly improved (5.9 vs 2.2, P < 0.001). One patient with ASIA impairment scale B had significantly improved to scale D. No major complications occurred. CONCLUSION: Our study showed that surgically managed TD fractures of the C2 showed a high incidence of other associated spine injuries including hangman's fracture and C2-3 discoligamentous injury. Therefore, special attention and careful radiologic evaluation are needed to investigate the presence of other associated spine injuries including hangman's fracture and C2-3 discoligamentous injury, which are likely to require surgery.


Assuntos
Vértebra Cervical Áxis/lesões , Vértebra Cervical Áxis/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas da Coluna Vertebral/cirurgia , Fusão Vertebral/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Retrospectivos , Adulto Jovem
13.
J Clin Med ; 10(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34768463

RESUMO

The thoracolumbar injury classification and severity score (TLICS) system help surgeons decide whether patients should undergo initial operative treatment or nonoperative treatment. However, the best treatment for patients with TLICS 4 fracture remains unknown. The aim of this study was to identify the risk factors for nonoperative treatment failure in patients with TLICS 4 fracture and establish treatment standards for TLICS 4 fractures. This study included 44 patients with TLICS 4 fracture who initially received nonoperative treatment. We divided these patients into two groups: the successful nonoperative treatment group included 18 patients, and the operative treatment group after nonoperative treatment failure included 26 patients. In multiple logistic regression analysis, spinal canal compromise (odd ratio = 1.316) and kyphotic angle (odd ratio = 1.416) were associated with nonoperative treatment failure in patients with TLICS 4 fracture. Other factors, including age, sex, BMI, initial VAS score, and loss of vertebral body height, were not significantly associated with nonoperative treatment failure in these patients. Spinal canal compromise and kyphotic angle were associated with nonoperative treatment failure in patients with TLICS 4 fracture. Therefore, we recommend the surgeon observe spinal canal compromise and kyphotic angle more carefully when deciding on the treatment of patients with TLICS 4 fracture.

14.
Medicina (Kaunas) ; 57(10)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34684088

RESUMO

Factures in ankylosing spondylitis (AS) patients tend to occur due to the absence of motion between vertebrae, poor bone quality, and a long lever arm that generates extension force. However, most patients have a history of at least minor trauma. The aim of this report was that a vertebral fracture in a patient with AS can be caused not only by minor trauma, but also by position changes or maintenance of position for examination due to structural weakness. A 75-year-old woman with AS visited her local hospital on foot for back pain. She usually had back pain. However, she had increased back pain after falling over three weeks prior. In plain radiographs, no fracture was apparent. The doctor tried to perform magnetic resonance imaging (MRI) for further evaluation. However, several attempts of MRI failed due to continuous movement arising from pain. As a result, MRI was performed under spinal anesthesia for pain control. However, complete paraplegia developed during the MRI examination. MRI showed extension-type vertebral fracture with displacement and the patient was transferred to our hospital. We performed emergency posterior fusion, but neurological symptoms did not improve. This case suggests the need for careful positioning, sedation, or anesthesia when performing an examination or surgery in AS patients. We recommend that all patients with AS should be carefully positioned at all times during testing or surgery.


Assuntos
Raquianestesia , Fraturas Espontâneas , Fraturas da Coluna Vertebral , Espondilite Anquilosante , Idoso , Raquianestesia/efeitos adversos , Feminino , Humanos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologia , Espondilite Anquilosante/complicações , Espondilite Anquilosante/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/lesões
15.
J Clin Med ; 10(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34575236

RESUMO

Development of adjacent segment pathology leading to secondary operation is a matter of concern after anterior cervical discectomy and fusion (ACDF). Some studies have reported anatomic difference between races, but no epidemiological data on prevalence of clinical adjacent segment pathology (cASP) among races or continents has been published. The purpose of this study was to compare the prevalence of cASP that underwent surgery after monosegmental ACDF among continents by meta-analysis. MEDLINE, EMBASE, and Cochrane Library with manual searching in key journals, reference lists, and the National Technical Information Service were searched from inception to December 2018. Twenty studies with a total of 2009 patients were included in the meta-analysis. We extracted the publication details, sample size, and prevalence of cASP that underwent surgery. A total of 15 papers from North America, three from Europe, and two from Asia met the inclusion criteria. A total number of 2009 patients underwent monosegmental ACDF, and 113 patients (5.62%) among them had cASP that underwent surgery. The rate of cASP that underwent surgery was 4.99% in the North America, 3.65% in the Europe, 6.34% in the Asia, and there were no statistically significant differences (p = 0.63). The current study using the method of meta-analysis revealed that there were no significant differences in the rate of cASP that underwent surgery after ACDF among the continents.

16.
J Clin Med ; 10(17)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34501435

RESUMO

Spine surgeons often confuse C2 pedicle fractures (PFs) with pars interarticularis fractures. In addition, little information is available about the characteristics and treatment strategies for C2 PFs. We sought to investigate the characteristics of C2 PFs and to propose an appropriate treatment strategy. A total of forty-nine patients with C2 PFs were included in this study. We divided these patients into unilateral and bilateral C2 PF groups. The incidence rates and characteristics of other associated C2 and C2-3 injuries, and other cervical injuries, were evaluated. In addition, treatment methods and outcomes were analyzed. Twenty-two patients had unilateral C2 PFs and twenty-seven patients had bilateral C2 PFs. Among the cases of unilateral C2 PFs, all patients had one or more other C2 fractures, and twenty patients (90.9%) had one or two C2 body fractures. Meanwhile, among the cases of bilateral C2 PF, all patients had two or more other C2 fractures and one or two C2 body fractures. In unilateral C2 PFs, three patients with C2-3 anterior slip or adjacent cervical spine (C1-3) injury underwent surgery and nineteen patients (86.4%) were treated with conservative methods. In bilateral C2 PFs, three patients with C2-3 anterior slip or SCI at C2-3 underwent surgery and twenty-four patients (88.9%) were treated with conservative methods. Our results showed that C2 PFs do not occur alone and are always accompanied by other associated C2 injuries. C2 PFs should, generally, be thought of as a more complex fracture type than hangman's fracture or dens fracture. Despite the complex fracture characteristics, most C2 PFs can be managed with conservative treatment. However, surgical treatments should be considered if the C2 PFs are accompanied by the C2-3 anterior slip and adjacent cervical spine injury.

17.
Sci Rep ; 11(1): 13853, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226604

RESUMO

The purpose of this study is to check the effectiveness of the analysis method that separates and quantifies ß-caryophyllene among clove extracts and validate according to current ICH guidelines. The ß-caryophyllene was active constituent of clove buds. The developed method gave a good detection response. In the specificity test, the standard solution was detected at about 17.32 min, and the test solution was detected at 17.32 min. The linearity of ß-caryophyllen was confirmed, and at this time, the correlation coefficient (R2) of the calibration curve showed a high linearity of 0.999 or more in the concentration range. The levels of LOD and LOQ were 1.28 ug/mL and 3.89 ug/mL, respectively. The accuracy was confirmed to be 101.6-102.2% and RSD 0.95 ~ 1.31%. As a result of checking the repeatability and inter-tester reproducibility to confirm the precision, the RSD was found to be 1.34 ~ 2.69%. This validated GC method was successfully applied to a soft capsule containing clove extract and other materials for clinical trials. Therefore, this method can be used as an analytical tool for quality control of various samples, including clove extracts and their products of food and pharmaceutical uses.

18.
J Clin Med ; 10(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068661

RESUMO

Many anterior C2 (2nd cervical vertebra) tear drop (TD) fractures can be successfully managed with conservative treatment. However, due to the occurrence of nonunion, large-sized or complex anterior C2 TD fractures undergo surgical treatment. To date, no surgical treatment guidelines are available about anterior C2 TD fractures. Therefore, we performed this study to investigate the factors that may affect nonunion for anterior C2 TD fractures and to suggest surgical treatment guidelines. Thirty-three patients with anterior C2 TD fractures, who underwent conservative treatment and had a minimum 1-year follow-up, were divided into union (N = 26) and nonunion (N = 7) groups. Their radiological and clinical data were analyzed retrospectively and compared between the two groups. The avulsion fracture ratio (29.5% vs. 43.3%, p < 0.05) and fracture displacement (3.6 mm vs. 5.1 mm, p < 0.05) were higher in the nonunion group compared to the union group. Incidence of associated C2 injury was higher in the nonunion group compared to the union group (15.4% vs. 57.1%, p < 0.05). Union status was negatively correlated with associated C2 injury (correlation coefficient, CC = -0.398, p < 0.05). Our results suggest that surgical treatment could be considered for anterior C2 TD fractures with an avulsion fracture ratio > 43%, fracture displacement > 5 mm, or associated C2 injury.

19.
Orthop Surg ; 13(4): 1378-1388, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34047054

RESUMO

OBJECTIVE: To investigate the characteristics of transverse fractures of the C2 axis body diagnosed on sagittal computed tomography (CT) and to propose new classification and appropriate treatment strategies. METHODS: A retrospective study was performed by enrolling 49 patients (26 men and 23 women) with transverse fractures of the C2 axis body who were treated at four national trauma centers of tertiary university hospitals from January 2000 to December 2017. The mean age of the patients was 60.8 years (ranging from 21 to 90 years). We classified 49 transverse fractures of the C2 body into three types based on fracture trajectories involving superior articular facet (SAF) and lateral cortex (LC) of the C2 body on coronal CT as follows: Type 1, involvement of C2 SAF on both sides; Type 2, unilateral involvement of C2 SAF on one side and LC on the other side; Type 3, involvement of LC on both sides. The characteristics, treatment methods, and results of 49 transverse fractures of the C2 body were analyzed. Mean follow-up was 12.6 months (ranging from 12 to 26 months). RESULTS: Twenty-six (53.1%) patients were Type 1, 21 (42.9%) were Type 2, and 2 (4.0%) were Type 3. Correlation coefficients for intra-observer and inter-observer reliabilities of classification were 0.723 and 0.598 (both, P < 0.001), respectively. About 40.8% (7 Type 1 and 13 Type 2) of the patients had fracture displacement >3 mm; Incidence of fracture displacement >3 mm was higher in Type 2 than Type 1 (61.9% vs 26.9%, P < 0.05). About 79.6% (20 Type 1, 17 Type 2 and 2 Type 3) of the patients were treated conservatively, and 20.4% (6 Type 1 and 4 Type 2) underwent surgery. At last follow-up, 47 out of 49 patients achieved fusion; overall fusion rate was 95.9%. All conservatively treated Type 1 and Type 3 patients achieved fusion. Out of 17 conservatively treated Type 2 patients, 15 achieved fusion but two developed nonunion; however, two nonunion patients opted not to undergo surgery. Subgroup analysis showed that Philadelphia brace caused nonunion significantly in fracture displacement >3 mm compared to Minerva brace/Halovest (100% vs 0%, P < 0.05). All surgically treated Type 1 and 2 patients achieved fusion. In terms of clinical outcomes, neck pain visual analog scale and neck disability index were significantly improved (both, P < 0.01). According to Odom's criteria, 93.9% (46/49) of the patients achieved satisfactory outcomes. No major complications occurred. CONCLUSIONS: The majority of transverse fractures of C2 body can be treated conservatively. However, surgery or rigid Minerva brace/Halovest should be considered for Type 2 transverse fractures of the C2 body with fracture displacement >3 mm.


Assuntos
Vértebra Cervical Áxis/diagnóstico por imagem , Vértebra Cervical Áxis/lesões , Fraturas da Coluna Vertebral/classificação , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Radiografia , Estudos Retrospectivos , Adulto Jovem
20.
Clin Neurol Neurosurg ; 206: 106701, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34049751

RESUMO

BACKGROUND: Highly displaced Hangman's fracture is a very rare and extremely unstable fracture of the C2 axis. Combined anteroposterior or posterior long-segment fusion surgery is typically performed for the treatment of highly displaced Hangman's fracture. However, these kinds of surgeries increase the risk of complications, loss of motion, and hospital costs. OBJECTIVE: We sought to investigate the surgical outcomes of anterior C2-3 fusion surgery alone for highly displaced Hangman's fractures with severe angulation of C2-3 by more than 30° and discoligamentous injury. METHODS: A total of five patients (four men and one woman) were included in this study with a mean age of 40.4 years (range, 26-70 years). The mean follow-up period after surgery was 37.2 months (range, 12-96 months). The fracture characteristics, treatment methods, and outcomes were retrospectively analyzed. RESULTS: All five patients had type II Hangman's fractures (according to the Levine and Edwards classification scheme). None of the included patients had neurologic deficit or other spine injury but all patients had complete C2-3 discoligamentous injury. Before surgery, all patients successfully achieved closed reduction by skull traction, followed by C2-3 anterior decompression and fusion (ACDF) with plating. For interbody grafting, three patients received a polyetheretherketone (PEEK) cage filled with an autogenous cancellous iliac bone graft and two received autogenous tricortical iliac bone grafts. Severe angulation (39.2° vs. 3.0°, P < 0.001) and severe displacement (76.1% vs. 4.0%, P < 0.001) of C2-3 were both significantly corrected after surgery. All patients had achieved solid fusion at last follow-up. In terms of clinical outcomes, the mean neck pain visual analog scale score was significantly improved (8.6 points vs. 1.8 points, P < 0.001). The mean neck disability index value was also significantly improved (45.4 points vs. 13.0 points, P < 0.01). According to Odom's criteria, all patients achieved satisfactory outcomes. No major complications occurred. One patient complained of dysphagia, but recovered after three months with conservative treatment. CONCLUSIONS: Preoperative closed reduction and anterior C2-3 fusion surgery alone should be considered as a less-invasive and useful surgical option for highly displaced Hangman's fracture with severe angulation of C2-3, which is an extremely unstable fracture of the C2 axis.


Assuntos
Vértebras Cervicais/lesões , Vértebras Cervicais/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Fusão Vertebral/métodos , Adulto , Idoso , Redução Fechada/métodos , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA