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1.
Proc Natl Acad Sci U S A ; 119(51): e2210235119, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36516067

RESUMO

We report that high-quality single crystals of the hexagonal heavy fermion material uranium diauride (UAu2) become superconducting at pressures above 3.2 GPa, the pressure at which an unusual antiferromagnetic state is suppressed. The antiferromagnetic state hosts a marginal fermi liquid and the pressure evolution of the resistivity within this state is found to be very different from that approaching a standard quantum phase transition. The superconductivity that appears above this transition survives in high magnetic fields with a large critical field for all field directions. The critical field also has an unusual angle dependence suggesting that the superconductivity may have an order parameter with multiple components. An order parameter consistent with these observations is predicted to host half-quantum vortices (HQVs). Such vortices can be topologically entangled and have potential applications in quantum computing.

2.
Development ; 148(12)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34013332

RESUMO

Eukaryotic translation initiation factor 4E (eIF4E) mediates cap-dependent translation. Genetic and inhibitor studies show that eIF4E expression is required for the successful transition from maternal to embryonic control of mouse embryo development. eIF4E was present in the oocyte and in the cytoplasm soon after fertilization and during each stage of early development. Functional knockout (Eif4e-/-) by PiggyBac [Act-RFP] transposition resulted in peri-implantation embryonic lethality because of the failure of normal epiblast formation. Maternal stores of eIF4E supported development up to the two- to four-cell stage, after which new expression occurred from both maternal and paternal inherited alleles. Inhibition of the maternally acquired stores of eIF4E (using the inhibitor 4EGI-1) resulted in a block at the two-cell stage. eIF4E activity was required for new protein synthesis in the two-cell embryo and Eif4e-/- embryos had lower translational activity compared with wild-type embryos. eIF4E-binding protein 1 (4E-BP1) is a hypophosphorylation-dependent negative regulator of eIF4E. mTOR activity was required for 4E-BP1 phosphorylation and inhibiting mTOR retarded embryo development. Thus, this study shows that eIF4E activity is regulated at key embryonic transitions in the mammalian embryo and is essential for the successful transition from maternal to embryonic control of development.


Assuntos
Desenvolvimento Embrionário/genética , Fator de Iniciação 4E em Eucariotos/genética , Regulação da Expressão Gênica no Desenvolvimento , Animais , Elementos de DNA Transponíveis , Embrião de Mamíferos , Fator de Iniciação 4E em Eucariotos/metabolismo , Imunofluorescência , Camundongos , Camundongos Knockout , Oócitos/metabolismo , Biossíntese de Proteínas
3.
Proc Natl Acad Sci U S A ; 118(49)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34873053

RESUMO

The term Fermi liquid is almost synonymous with the metallic state. The association is known to break down at quantum critical points (QCPs), but these require precise values of tuning parameters, such as pressure and applied magnetic field, to exactly suppress a continuous phase transition temperature to the absolute zero. Three-dimensional non-Fermi liquid states, apart from superconductivity, that are unshackled from a QCP are much rarer and are not currently well understood. Here, we report that the triangular lattice system uranium diauride (UAu2) forms such a state with a non-Fermi liquid low-temperature heat capacity [Formula: see text] and electrical resistivity [Formula: see text] far below its Néel temperature. The magnetic order itself has a novel structure and is accompanied by weak charge modulation that is not simply due to magnetostriction. The charge modulation continues to grow in amplitude with decreasing temperature, suggesting that charge degrees of freedom play an important role in the non-Fermi liquid behavior. In contrast with QCPs, the heat capacity and resistivity we find are unusually resilient in magnetic field. Our results suggest that a combination of magnetic frustration and Kondo physics may result in the emergence of this novel state.

4.
Sensors (Basel) ; 24(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38894445

RESUMO

The detection of seismic activity precursors as part of an alarm system will provide opportunities for minimization of the social and economic impact caused by earthquakes. It has long been envisaged, and a growing body of empirical evidence suggests that the Earth's electromagnetic field could contain precursors to seismic events. The ability to capture and monitor electromagnetic field activity has increased in the past years as more sensors and methodologies emerge. Missions such as Swarm have enabled researchers to access near-continuous observations of electromagnetic activity at second intervals, allowing for more detailed studies on weather and earthquakes. In this paper, we present an approach designed to detect anomalies in electromagnetic field data from Swarm satellites. This works towards developing a continuous and effective monitoring system of seismic activities based on SWARM measurements. We develop an enhanced form of a probabilistic model based on the Martingale theories that allow for testing the null hypothesis to indicate abnormal changes in electromagnetic field activity. We evaluate this enhanced approach in two experiments. Firstly, we perform a quantitative comparison on well-understood and popular benchmark datasets alongside the conventional approach. We find that the enhanced version produces more accurate anomaly detection overall. Secondly, we use three case studies of seismic activity (namely, earthquakes in Mexico, Greece, and Croatia) to assess our approach and the results show that our method can detect anomalous phenomena in the electromagnetic data.

5.
Phys Rev Lett ; 126(19): 197203, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34047591

RESUMO

The theory of quantum order-by-disorder (QOBD) explains the formation of modulated magnetic states at the boundary between ferromagnetism and paramagnetism in zero field. PrPtAl has been argued to provide an archetype for this. Here, we report the phase diagram in magnetic field, applied along both the easy a axis and hard b axis. For field aligned to the b axis, we find that the magnetic transition temperatures are suppressed and at low temperature there is a single modulated fan state, separating an easy a axis ferromagnetic state from a field polarized state. This fan state is well explained with the QOBD theory in the presence of anisotropy and field. Experimental evidence supporting the QOBD explanation is provided by the large increase in the T^{2} coefficient of the resistivity and direct detection of enhanced magnetic fluctuations with inelastic neutron scattering, across the field range spanned by the fan state. This shows that the QOBD mechanism can explain field induced modulated states that persist to very low temperature.

6.
BMC Musculoskelet Disord ; 19(1): 205, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29945574

RESUMO

BACKGROUND: The theoretical benefits of a mobile bearing design in Total Knee Arthroplasty (TKA) include increased articular surface conformity with a reduction in both polyethylene wear and implant interface shear. However, to date these theoretical advantages have not been translated into published evidence of superior survivorship. This paper presents the results of a prospective, non-comparative study evaluating the performance of the mobile bearing Low Contact Stress LCS Complete Rotating Platform TKA in a largely cementless cohort without patellar resurfacing. METHODS: 237 consecutive patients (240 knees) undergoing primary TKA were prospectively recruited. All received the LCS Complete Rotating Platform TKA (DePuy International, Leeds, UK). Clinical and radiographic assessments were performed at 3, 12, 60 and 120 months post-operatively. Radiographic evaluation was performed by an independent external surgeon. RESULTS: The mean age was 70.3 years. 77.5% of cases were cementless. Radiographic assessment suggested excellent femoral component fixation. 22 tibial radiolucent lines (RLLs) > 1 mm were observed in 12 knees. No RLLs were progressive. There have been two revisions; one for late infection and one for aseptic loosening. No patients underwent secondary patellar resurfacing. The cumulative implant survivorship, using component revision for any reason as the endpoint, was 98.9% (95% CI, 95.6 to 99.7%) at 10 years. CONCLUSIONS: The excellent survivorship at a minimum 10-year follow-up supports the use of uncemented porous coated fixation without patellar resurfacing with the non-posterior stabilized LCS Complete Rotating Platform TKA.


Assuntos
Artroplastia do Joelho/métodos , Artroplastia do Joelho/normas , Patela/diagnóstico por imagem , Patela/cirurgia , Sobrevivência , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
7.
J Sci Food Agric ; 97(12): 4075-4086, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28205235

RESUMO

BACKGROUND: In northern Australia, beef cattle grazed extensively on tropical rangelands are responsible for 5% of the nation's total greenhouse gas emissions. Methane (CH4 ) is a potent greenhouse gas and in grazing ruminants might be mitigated by selecting forages that, when consumed, produce less CH4 when fermented by rumen microbes. This study examined variability in the in vitro fermentation patterns, including CH4 production of selected tropical grasses and legumes, to identify candidates for CH4 mitigation in grazing livestock in northern Australia. RESULTS: Nutritive values and fermentation parameters varied between plant species and across seasons. Grasses with a relatively low methanogenic potential were Urochloa mosambicensis (wet summer), Bothriochloa decipiens (autumn), Sorghum plumosum (winter) and Andropogon gayanus (spring), while the legumes were Calliandra calothyrsus (wet summer and autumn), Stylosanthes scabra (winter) and Desmanthus leptophyllus (spring). There was some correlation between CH4 production and overall fermentation (volatile fatty acid concentrations) in grasses (R2 = 0.67), but not in legumes (R2 = 0.01) and there were multiple plants that had lower CH4 not associated with reduction in microbial activity. CONCLUSION: Differences in nutrient concentrations of tropical grasses and legumes may provide opportunities for productive grazing on these pastures, while offering some CH4 mitigation options in the context of northern Australian extensive beef farming systems. © 2017 Society of Chemical Industry.


Assuntos
Ração Animal/análise , Bovinos/metabolismo , Fabaceae/metabolismo , Poaceae/metabolismo , Animais , Austrália , Fabaceae/química , Metano/análise , Metano/metabolismo , Valor Nutritivo , Poaceae/química , Carne Vermelha/análise , Rúmen/metabolismo
8.
Reprod Fertil Dev ; 27(8): 1125-36, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24965854

RESUMO

The processes of assisted reproductive technologies (ART) involve a variety of interventions that impact on the oocyte and embryo. Critically, these interventions cause considerable stress and coincide with important imprinting events throughout gametogenesis, fertilisation and early embryonic development. It is now accepted that the IVM and in vitro development of gametes and embryos can perturb the natural course of development to varying degrees of severity. Altered gene expression and, more recently, imprinting disorders relating to ART have become a focused area of research. Although various hypotheses have been put forward, most research has been observational, with little attempt to discover the mechanisms and periods of sensitivity during embryo development that are influenced by the culture conditions following fertilisation. The embryo possesses innate survival factor signalling pathways, yet when an embryo is placed in culture, this signalling in response to in vitro stress becomes critically important in mitigating the effects of stresses caused by the in vitro environment. It is apparent that not all embryos possess this ability to adequately adapt to the stresses experienced in vitro, most probably due to an inadequate oocyte. It is speculated that it is important that embryos use their survival signalling mechanisms to maintain normal epigenetic programming. The seeming redundancy in the function of various survival signalling pathways would support this notion. Any invasion into the natural, highly orchestrated and dynamic process of sexual reproduction could perturb the normal progression of epigenetic programming. Therefore the source of gametes and the subsequent culture conditions of gametes and embryos are critically important and require careful attention. It is the aim of this review to highlight avenues of research to elucidate the effects of stress and the relationship with epigenetic programming. The short- and long-term health and viability of human and animal embryos derived in vitro will also be discussed.


Assuntos
Desenvolvimento Embrionário/fisiologia , Epigênese Genética/fisiologia , Técnicas de Reprodução Assistida , Estresse Fisiológico/fisiologia , Animais , Técnicas de Cultura Embrionária , Feminino , Humanos , Gravidez
9.
Genet Sel Evol ; 44: 22, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-22839739

RESUMO

BACKGROUND: Infectious bovine keratoconjunctivitis (IBK) or 'pinkeye' is an economically important ocular disease that significantly impacts animal performance. Genetic parameters for IBK infection and its genetic and phenotypic correlations with cattle tick counts, number of helminth (unspecified species) eggs per gram of faeces and growth traits in Australian tropically adapted Bos taurus cattle were estimated. METHODS: Animals were clinically examined for the presence of IBK infection before and after weaning when the calves were 3 to 6 months and 15 to 18 months old, respectively and were also recorded for tick counts, helminth eggs counts as an indicator of intestinal parasites and live weights at several ages including 18 months. RESULTS: Negative genetic correlations were estimated between IBK incidence and weight traits for animals in pre-weaning and post-weaning datasets. Genetic correlations among weight measurements were positive, with moderate to high values. Genetic correlations of IBK incidence with tick counts were positive for the pre-weaning and negative for the post-weaning datasets but negative with helminth eggs counts for the pre-weaning dataset and slightly positive for the post-weaning dataset. Genetic correlations between tick and helminth eggs counts were moderate and positive for both datasets. Phenotypic correlations of IBK incidence with helminth eggs per gram of faeces were moderate and positive for both datasets, but were close to zero for both datasets with tick counts. CONCLUSIONS: Our results suggest that genetic selection against IBK incidence in tropical cattle is feasible and that calves genetically prone to acquire IBK infection could also be genetically prone to have a slower growth. The positive genetic correlations among weight traits and between tick and helminth eggs counts suggest that they are controlled by common genes (with pleiotropic effects). Genetic correlations between IBK incidence and tick and helminth egg counts were moderate and opposite between pre-weaning and post-weaning datasets, suggesting that the environmental and (or) maternal effects differ between these two growth phases. This preliminary study provides estimated genetic parameters for IBK incidence, which could be used to design selection and breeding programs for tropical adaptation in beef cattle.


Assuntos
Peso Corporal/genética , Doenças dos Bovinos/genética , Doenças dos Bovinos/parasitologia , Ceratoconjuntivite/veterinária , Análise de Variância , Animais , Austrália/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Estudos de Associação Genética , Incidência , Ceratoconjuntivite/genética , Ceratoconjuntivite/parasitologia , Modelos Estatísticos , Linhagem , Fenótipo , Rhipicephalus/patogenicidade , Infestações por Carrapato/complicações , Infestações por Carrapato/genética , Infestações por Carrapato/veterinária
10.
Radiol Case Rep ; 17(2): 364-367, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34925666

RESUMO

Congestive heart failure (CHF) patients have typical radiological features that assist in diagnosis. This is a case that demonstrates an atypical radiologic presentation for CHF which showed diffuse pulmonary nodules on CT. Diffuse nodules can be present in several disease processes and clinical correlation is a necessity for diagnosis. It is important for radiologists and clinicians to be aware of uncommon radiological features of CHF to avoid unnecessary procedures or treatments.

11.
Radiol Case Rep ; 17(9): 3456, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35909927

RESUMO

[This corrects the article DOI: 10.1016/j.radcr.2021.02.043.].

12.
Bio Protoc ; 12(11): e4441, 2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35799905

RESUMO

This protocol describes a method to assess relative changes in the level of global protein synthesis in the preimplantation embryo using the Click-iT ® Plus OPP Protein Synthesis Assays. In this assay, O-propargyl-puromycin (OPP), an analog of puromycin, is efficiently incorporated into the nascent polypeptide of newly translated proteins in embryonic cells. OPP is fluorescently labeled with a photostable Alexa Fluor TM dye and detected with fluorescence microscopy. The intensity of the fluorescence is quantitatively analyzed. This is a fast, sensitive, and non-radioactive method for the detection of protein synthesis in early embryo development. It provides a tool for analyzing the temporal regulation of protein synthesis, as well as the effects of changes in the embryonic microenvironment, and pharmacological and genetic modulations of embryo development. Graphical abstract: Figure 1. Brief overview of the procedures of the Click-iT ® Plus OPP Alexa Fluor ® protein synthesis assay in embryonic cells. (A) Set up OPP treatments: (1) Set up microdrops containing 50 µL of OPP working solution and label different treatments on the back of culture dishes ( e.g. , T0, T1, T2, and T3); (2) The drops are overlain with 2-3 mm heavy paraffin oil and then equilibrated in incubator for 2 h; (3) Collect the embryos from female reproductive tracts or following in vitro culture in desired treatments; (4) Culture embryos in the equilibrated OPP working solution for 2-6 h. ( B ) Example of OPP detection procedures working with 60-well plates labeled as T0, T1, T2, T3, T4, and T5 for different treatments: (1) The first 60-well plate is used for the procedures of washing, fixation, permeabilization, and Click-iT ® OPP detection. (2) The second 60-well plate is for DNA staining and washing. (C) Slide preparation: (1) Label the required number of slides and set up vaseline coverslip supports; (2) Add mounting medium; (3) Transfer embryos into mounting medium; (4) Set coverslip; (5) Seal the coverslip with nail polish.

13.
Radiol Case Rep ; 16(5): 1165-1168, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33777281

RESUMO

An ectopic pregnancy is the implantation of a fertilized ovum in a location other than the main cavity of the uterus. Ectopic pregnancies are reported in approximately 1%-2% of pregnancies, and while 95% of ectopic pregnancies are in fallopian tubes, only 3% are in ovarian, cervical, or abdominal sites. We present a case of a 38-year-old female with acute onset of severe lower abdominal pain, sepsis, chills, and diarrhea who was evaluated with a CT of the abdomen and pelvis with IV contrast only. The imaging revealed a likely second trimester age fetal skeleton with a partially collapsed calvarium within the peritoneal cavity and an abnormal complex cystic lesion in the right adnexal area. In this case, the patient successfully underwent exploratory laparotomy with removal of both the abdominal ectopic pregnancy and the tubo-ovarian mass.

14.
Radiol Case Rep ; 16(6): 1391-1394, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33912253

RESUMO

Mesenchymal tumors make up only about 1% of primary GI tumors, with Gastrointestinal Stromal Tumors (GIST) being the most common nonepithelial GI neoplasms. They are derived from the Interstitial cells of Cajal (ICC), and occur predominantly in older individuals, with a mean age of diagnosis of 64 years. Here we discuss the case of a 39-year-old female with atypical thoracic back pain wrapping around to the front and migrating diffuse abdomen pain that sometimes radiates into the chest. Upon imaging, a gastric GIST of the greater curve of the stomach was found incidentally on investigation of a pancreatic mass that was revealed to be a co-occurring pancreatic neuroendocrine tumor. For management of the gastric GIST and pancreatic neuroendocrine tumor, this patient underwent partial gastrectomy with gastrojejunostomy, partial pancreatectomy, splenectomy, and cholecystectomy with no complications.

15.
Arthroplast Today ; 11: 222-228, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34692959

RESUMO

BACKGROUND: Achieving accurate and consistent acetabular component orientation remains a major challenge in total hip arthroplasty. METHODS: We used a pelvic model to compare freehand techniques vs mechanical and anatomical alignment guides in achieving a target operative inclination (OI) and operative anteversion (OA). Thirty subjects comprising consultant orthopedic surgeons, orthopedic trainees, and nonsurgical staff positioned an acetabular component in a pelvic model using 3 different methods for guiding inclination and another 3 for guiding version. RESULTS: Using either a standard mechanical alignment guide (MAG) or a spirit level MAG technique eliminated outliers from target OI, while the freehand method resulted in 46.7% of measurements outside the OI target range. The spirit level MAG technique significantly outperformed the standard MAG technique in median unsigned deviation from target OI (0.8° vs 2.1°, P < .001). Either method of referencing the transverse acetabular ligament for version yielded lower deviations from target OA than the freehand method and fewer outliers from the ±5° target range. Surgical experience was not a significant factor for accurately achieving target OI and OA. CONCLUSIONS: Even in an idealized in vitro model, a wide range of OI and OA is seen with the freehand technique of cup placement by subjects of all levels of surgical experience. Using either a standard MAG or a spirit level MAG reduces deviations in target OI, with the spirit level MAG method yielding the best accuracy. Using the transverse acetabular ligament to guide cup anteversion yields more accurate OA.

16.
J Phys Condens Matter ; 32(41): 415602, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32531764

RESUMO

A better understanding of the synthesis conditions, composition and physical properties of UTe2 are required to interpret previously reported unconventional superconductivity. Here we report how the superconducting properties of single crystals depend on the ratio of elements present in their synthesis by chemical vapour transport. We have obtained crystals with the highest reported ambient pressure T c and a larger superconducting heat capacity jump from a growth with a U:Te ratio different from that widely used in the literature. For these crystals, the ratio of residual heat capacity in the superconducting state to that of the normal state, γ*/γ N, is significantly lower than 0.5, reported elsewhere. An upturn in the heat capacity below 200 mK is also reduced compared to other studies and is well described by a Schottky anomaly and residual Sommerfeld term rather than quantum critical behaviour.

17.
Cell Rep ; 30(6): 1670-1681.e7, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32049001

RESUMO

Reproductive aging in female mammals is an irreversible process associated with declining oocyte quality, which is the rate-limiting factor to fertility. Here, we show that this loss of oocyte quality with age accompanies declining levels of the prominent metabolic cofactor nicotinamide adenine dinucleotide (NAD+). Treatment with the NAD+ metabolic precursor nicotinamide mononucleotide (NMN) rejuvenates oocyte quality in aged animals, leading to restoration in fertility, and this can be recapitulated by transgenic overexpression of the NAD+-dependent deacylase SIRT2, though deletion of this enzyme does not impair oocyte quality. These benefits of NMN extend to the developing embryo, where supplementation reverses the adverse effect of maternal age on developmental milestones. These findings suggest that late-life restoration of NAD+ levels represents an opportunity to rescue female reproductive function in mammals.


Assuntos
Fertilidade/genética , NAD/metabolismo , Envelhecimento , Animais , Feminino , Camundongos , Camundongos Transgênicos
18.
Sensors (Basel) ; 9(5): 3586-603, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22412327

RESUMO

Remote monitoring of animal behaviour in the environment can assist in managing both the animal and its environmental impact. GPS collars which record animal locations with high temporal frequency allow researchers to monitor both animal behaviour and interactions with the environment. These ground-based sensors can be combined with remotely-sensed satellite images to understand animal-landscape interactions. The key to combining these technologies is communication methods such as wireless sensor networks (WSNs). We explore this concept using a case-study from an extensive cattle enterprise in northern Australia and demonstrate the potential for combining GPS collars and satellite images in a WSN to monitor behavioural preferences and social behaviour of cattle.

19.
Hip Int ; 28(3): 234-239, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-30165761

RESUMO

AIMS: To determine which of 3 methods of cup insertion most accurately achieved a target apparent operative inclination (AOI) of 35° ± 2.5°: (1) Freehand; (2) Modified Mechanical Alignment Guide (MAG); or (3) Digital Inclinometer assisted. METHODS: Using a cementless cup via a posterior approach in lateral decubitus 270 participants were recruited, with 90 randomised to each method. The primary outcome was the unsigned deviation from target AOI. The digital inclinometer was used to measure AOI in all cases, though the surgeon remained blinded to the reading intraoperatively for both the Freehand and MAG methods. RESULTS: Mean deviation from target AOI for the Freehand, Modified 35° MAG and Digital Inclinometer techniques was 2.9°, 1.8° and 1.3° respectively. When comparing mean deviation from target AOI, statistically significant differences between the Freehand / Inclinometer groups ( p < 0.001), the Freehand / Modified 35° MAG groups ( p < 0.001) and the Digital Inclinometer / Modified 35° MAG groups ( p < 0.023) were evident. The Digital Inclinometer technique enabled the surgeon to achieve a target AOI of 35° ± 2.5° in 88% of cases, compared to 71% of Modified 35° MAG cases and only 51% of Freehand cases. DISCUSSION: The Digital Inclinometer and the Modified 35° MAG techniques were both more accurate than the Freehand technique, with the Digital Inclinometer technique proving most accurate overall. Radiographic inclination (RI) is also influenced by operative anteversion; however, the greatest source of error with respect to RI occurs when the pelvic sagittal plane is not horizontal at the time of acetabular component insertion. Clinical Trial Protocol number: NCT01831401.


Assuntos
Artroplastia de Quadril/métodos , Acetábulo/cirurgia , Idoso , Feminino , Prótese de Quadril , Humanos , Masculino , Posicionamento do Paciente , Pelve
20.
Hip Int ; 28(3): 240-245, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-30165765

RESUMO

INTRODUCTION: The study aims were to identify the incidence of pelvic adduction during total hip arthroplasty (THA) in lateral decubitus and to determine, when aiming for 35° of apparent operative inclination (AOI), which of 3 operating table positions most accurately obtained a target radiographic inclination (RI) of 42°: (1) horizontal; (2) 7° head-down; (3) patient-specific position based on correction of pelvic adduction. METHODS: With patients seated on a levelled theatre table, a ruler incorporating a spirit level was used to draw transverse pelvic lines (TPLs) on the skin overlying the pelvis and sacrum. Subsequently, when positioned in lateral decubitus these lines provided a measure of pelvic adduction. 270 participants were recruited, with 90 randomised to each group for operating table position. In all cases target AOI was 35°, aiming to achieve a target RI of 42°. The primary outcome measure was absolute (unsigned) deviation from the target RI of 42°. RESULTS: 266/270 patients demonstrated pelvic adduction (overall mean 4.4°, range 0- 9.2°). No patients demonstrated pelvic abduction. There were significant differences in RI between each of the 3 groups. The horizontal table group displayed the highest mean RI. The patient specific table position group achieved the smallest absolute deviation from target RI of 42°. DISCUSSION: In lateral decubitus, unrecognised pelvic adduction is common and is an important contributor to unexpectedly high RI. The use of preoperative TPLs helps identify pelvic adduction and its subsequent correction reduces variability in RI. Clinical Trial Protocol number: NCT01831401.


Assuntos
Artroplastia de Quadril/métodos , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Idoso , Feminino , Humanos , Masculino , Posicionamento do Paciente , Pelve , Estudos Prospectivos , Radiografia , Amplitude de Movimento Articular
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