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2.
JBJS Rev ; 11(4)2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-37098128

RESUMO

¼: Obesity, defined as body mass index (BMI) ≥30, is a serious public health concern associated with an increased incidence of stroke, diabetes, mental illness, and cardiovascular disease resulting in numerous preventable deaths yearly. ¼: From 1999 through 2018, the age-adjusted prevalence of morbid obesity (BMI ≥40) in US adults aged 20 years and older has risen steadily from 4.7% to 9.2%, with other estimates showing that most of the patients undergoing hip and knee replacement by 2029 will be obese (BMI ≥30) or morbidly obese (BMI ≥40). ¼: In patients undergoing total joint arthroplasty (TJA), morbid obesity (BMI ≥40) is associated with an increased risk of perioperative complications, including prosthetic joint infection and mechanical failure necessitating aseptic revision. ¼: The current literature on the role that bariatric weight loss surgery before TJA has on improving surgical outcomes is split and referral to a bariatric surgeon should be a shared-decision between patient and surgeon on a case-by-case basis. ¼: Despite the increased risk profile of TJA in the morbidly obese cohort, these patients consistently show improvement in pain and physical function postoperatively that should be considered when deciding for or against surgery.


Assuntos
Artroplastia do Joelho , Cirurgia Bariátrica , Diabetes Mellitus , Obesidade Mórbida , Adulto , Humanos , Artroplastia do Joelho/efeitos adversos , Diabetes Mellitus/etiologia , Diabetes Mellitus/cirurgia , Incidência , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Obesidade Mórbida/epidemiologia
3.
Arch Orthop Trauma Surg ; 143(8): 5417-5423, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36629905

RESUMO

Leg-length discrepancy (LLD) presents a significant management challenge to orthopedic surgeons and remains a leading cause of patient dissatisfaction and litigation after total hip arthroplasty (THA). Over or under-lengthening of the operative extremity has been shown to have inferior outcomes, such as dislocation, exacerbation of back pain and sciatica, and general dissatisfaction postoperatively. The management of LLD in the setting of THA is multifactorial, and must be taken into consideration in the pre-operative, intra-operative, and post-operative settings. In our review, we aim to summarize the best available practices and techniques for minimizing LLD through each of these phases of care. Pre-operatively, we provide an overview of the appropriate radiographic studies to be obtained and their interpretation, as well as considerations to be made when templating. Intra-operatively, we discuss several techniques for the assessment of limb length in real time, and post-operatively, we discuss both operative and non-operative management of LLD. By providing a summary of the best available practices and strategies for mitigating the impact of a perceived LLD in the setting of THA, we hope to maximize the potential for an excellent surgical and clinical outcome.


Assuntos
Artroplastia de Quadril , Humanos , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Perna (Membro)/cirurgia , Desigualdade de Membros Inferiores/etiologia , Desigualdade de Membros Inferiores/cirurgia
4.
Sci Total Environ ; 858(Pt 3): 159974, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36347293

RESUMO

Managed turfgrass is a common component of urban landscapes that is expanding under current land use trends. Previous studies have reported high rates of soil carbon sequestration in turfgrass, but no systematic review has summarized these rates nor evaluated how they change as turfgrass ages. Here we conducted a meta-analysis of soil carbon sequestration rates from 63 studies globally, comprised mostly of C3 grass species in the U.S., including 24 chronosequence studies that evaluated carbon changes over 75 years or longer. We showed that turfgrass established within the last ten years had a positive mean soil C sequestration rate of 5.3 Mg CO2 ha-1 yr-1 (95% CI = 3.7-6.2), which is higher than rates reported for several soil conservation practices. Areas converted to turfgrass from forests were an exception, sometimes lost soil carbon, and had a cross-study mean sequestration rate that did not differ from 0. In some locations, soil C accumulated linearly with turfgrass age over several decades, but the major trend was for soil C accumulation rates to decline through time, reaching a cross-study mean sequestration rate that was not different from 0 at 50 years. We show that fitting soil C timeseries with a mechanistically derived function rather than purely empirical functions did not alter these conclusions, nor did employing equivalent soil mass versus fixed-depth carbon stock accounting. We conducted a partial greenhouse gas budget that estimated emissions from mowing, N-fertilizer production, and soil N2O emissions. When N fertilizer was applied, average maintenance emissions offset 32% of C sequestration in recently established turfgrass. Potential emission removals by turfgrass can be maximized with reduced-input management. Management decisions that avoid losing accrued soil C-both when turfgrass is first established and when it is eventually replaced with other land-uses-will also help maximize turfgrass C sequestration potential.


Assuntos
Sequestro de Carbono , Solo , Carbono
5.
Arch Orthop Trauma Surg ; 143(6): 3525-3533, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35986745

RESUMO

With the annual incidence of hip fractures and hip fracture fixation rising, the need for conversion total hip arthroplasty has also risen. About half of the 280,000 hip fractures that occur annually in the United States are extracapsular. Commonly extracapsular hip fractures are treated with either cephalomedullary nails (CMNs) or sliding hip screws (SHS). More recently, there has been a shift toward increased CMN use due to increased training with this fixation method as well as perioperative and biomechanical benefits. Given this shift, orthopedic surgeons need to understand the factors that lead to CMN failure. Failed CMN treatment leaves both patients and surgeons with few management options including revision fixation with or without osteotomy, conversion total hip arthroplasty, and conversion hemiarthroplasty. Surgeons must consider the patient and injury characteristics before deciding the best treatment plan. Conversion total hip arthroplasty is indicated in younger patients without femoral head and/or acetabular articular injury, degenerative joint disease, or avascular necrosis. Conversion total arthroplasty is a technically demanding and resource-intensive surgery associated with lower success rates and outcomes than primary total hip arthroplasty. Orthopedic surgeons should have thorough understanding of preoperative workup needed prior to surgery, implant selection associated with best outcomes, most common surgical approaches used, intraoperative considerations, and complications associated with conversion total hip arthroplasty. A comprehensive understanding of these concepts gives patients the best chance of having a successful outcome.


Assuntos
Artroplastia de Quadril , Fixação Intramedular de Fraturas , Fraturas do Quadril , Humanos , Fixação Interna de Fraturas , Fraturas do Quadril/cirurgia , Acetábulo/cirurgia
6.
J Am Chem Soc ; 144(43): 19953-19972, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36269121

RESUMO

The total syntheses of aflastatin A and its C3-C48 degradation fragment (6a, R = H) have been accomplished. The syntheses feature several complex diastereoselective fragment couplings, including a Felkin-selective trityl-catalyzed Mukaiyama aldol reaction, a chelate-controlled aldol reaction involving soft enolization with magnesium, and an anti-Felkin-selective boron-mediated oxygenated aldol reaction. Careful comparison of the spectroscopic data for the synthetic C3-C48 degradation fragment to that reported by the isolation group revealed a structural misassignment in the lactol region of the naturally derived degradation product. Ultimately, the data reported for the naturally derived aflastatin A C3-C48 degradation lactol (6a, R = H) were attributed to its derivative lactol trideuteriomethyl ether (6c, R = CD3). Additionally, the revised absolute configurations of six stereogenic centers (C8, C9, and C28-C31) were confirmed.


Assuntos
Aldeídos , Pirrolidinonas , Boro , Estereoisomerismo , Estrutura Molecular
8.
JBJS Rev ; 10(5)2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35613307

RESUMO

¼: Geriatric acetabular fractures are defined as fractures sustained by patients who are ≥60 years old. With the rapidly aging American populace and its increasingly active lifestyle, the prevalence of these injuries will continue to increase. ¼: An interdisciplinary approach is necessary to ensure successful outcomes. This begins in the emergency department with hemodynamic stabilization, diagnosis of the fracture, identification of comorbidities and concomitant injuries, as well as early consultation with the orthopaedic surgery service. This multifaceted approach is continued when patients are admitted, and trauma surgery, geriatrics, and cardiology teams are consulted. These teams are responsible for the optimization of complex medical conditions and risk stratification prior to operative intervention. ¼: Treatment varies depending on a patient's preinjury functional status, the characteristics of the fracture, and the patient's ability to withstand surgery. Nonoperative management is recommended for patients with minimally displaced fractures who cannot tolerate the physiologic stress of surgery. Percutaneous fixation is a treatment option most suited for patients with minimally displaced fractures who are at risk for displacing the fracture or are having difficulty mobilizing because of pain. Open reduction and internal fixation is recommended for patients with displaced acetabular fractures who are medically fit for surgery and have a displaced fracture pattern that would do poorly without operative intervention. Fixation in combination with arthroplasty can be done acutely or in delayed fashion. Acute fixation combined with arthroplasty benefits patients who have poorer bone quality and fracture characteristics that make healing unlikely. Delayed arthroplasty is recommended for patients who have had failure of nonoperative management, have a fracture pattern that is not favorable to primary total hip arthroplasty, or have developed posttraumatic arthritis.


Assuntos
Artroplastia de Quadril , Fraturas do Quadril , Fraturas da Coluna Vertebral , Acetábulo/lesões , Acetábulo/cirurgia , Idoso , Fixação Interna de Fraturas , Fraturas do Quadril/cirurgia , Humanos , Pessoa de Meia-Idade , Redução Aberta , Fraturas da Coluna Vertebral/cirurgia
9.
JAMA Netw Open ; 5(5): e2212397, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35583869

RESUMO

Importance: Greater difficulty in controlling blood pressure (BP) and adverse lifestyle practices such as higher salt intake or less physical activity may account for some of the differences between BP control rates in Black vs White adults, thereby exposing Black adults to a higher risk of vascular events. Objective: To determine whether a lifestyle coaching intervention or an enhanced pharmacotherapy protocol is more effective than usual care in improving BP control rates in Black adults treated within an integrated health care delivery system. Design, Setting, and Participants: Shake, Rattle & Roll, a cluster randomized clinical trial, was conducted from June 5, 2013, to June 11, 2018, in a large integrated health care delivery system. Enrollment was completed during a 12-month period and interventions were implemented for 12 months. Follow-up lasted 48 months after enrollment. Panels of Black adult members of the health care delivery system with BP of at least 140/90 mm Hg from 98 adult primary care physicians were randomly assigned at the primary care physician level to usual care (UC group [n = 1129]), enhanced pharmacotherapy monitoring (EP group [n = 346]) of current BP management protocol, or diet and lifestyle coaching consisting of photographs, stories, and recipes, for example, that are appropriate for Black adults (LC group [n = 286]) focused on the Dietary Approaches to Stop Hypertension (DASH) diet. Data were analyzed from June 1, 2016, to March 25, 2022. Interventions: The UC group received care per customary protocol. The EP group was contacted by a research nurse and/or a clinical pharmacist to discuss barriers to hypertension control, and drug therapy emphasized the use of thiazide diuretic intensification and addition of spironolactone as needed. The LC group received as many as 16 telephone sessions with a lifestyle coach and an emphasis on implementing reduction of sodium intake and the DASH diet. Main Outcomes and Measures: Intention-to-treat analysis of BP control rates at end of the 12-month intervention. Results: Among the 1761 participants, the mean (SD) age was 61 (13) years, and 1214 (68.9%) were women. At the end of the 12-month intervention period, there was no significant difference in BP control rate among study groups (UC, 61.8% [95% CI, 58.8%-64.9%]; EP, 64.5% [95% CI, 59.0%-69.4%]; LC, 67.8% [95% CI, 62.1%-73.2%]; LC vs EP, P = .07). However, greater BP control was present in the LC group vs UC at 24 months (UC, 61.2% [95% CI, 57.3%-64.7%]; EP, 67.6% [95% CI, 61.9%-72.8%]; LC, 72.4% [95% CI, 66.9%-78.1%]; LC vs UC, P = .001), and 48 months (UC, 64.5% [95% CI, 61.6%-67.2%]; EP, 66.5% [95% CI, 61.3%-71.3%]; LC, 73.1% [95% CI, 67.6%-77.9%]; LC vs UC, P = .006) after enrollment. The contribution of BP medication adherence to explain group differences was inconclusive. Conclusions and Relevance: In this cluster randomized clinical trial including Black adults with persistent uncontrolled hypertension, a 12-month LC intervention was more effective at controlling BP than UC at 24 and 48 months after enrollment. Further research is needed to explore the potential implementation of this intervention into clinical practice. Trial Registration: ClinicalTrials.gov Identifier: NCT01892592.


Assuntos
Abordagens Dietéticas para Conter a Hipertensão , Hipertensão , Tutoria , Adulto , Pressão Sanguínea , Feminino , Humanos , Hipertensão/tratamento farmacológico , Estilo de Vida , Masculino , Pessoa de Meia-Idade
10.
JBJS Rev ; 9(11)2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34757978

RESUMO

¼: A small yet growing subset of total joint arthroplasty (TJA) candidates are diagnosed with the hepatitis C virus (HCV), which is a known risk factor for periprosthetic joint infections. Given the poor outcomes associated with TJA infection, we recommend that candidates with HCV receive treatment prior to elective TJA. ¼: Interferon and ribavirin have historically been the standard treatment regimen for the management of HCV; however, adverse events and an inconsistent viral response have limited the efficacy of these therapies. The advent of direct-acting antivirals has resolved many of the issues associated with interferon and ribavirin regimens. ¼: Despite the success of direct-acting antivirals, there are still barriers to seeking treatment for TJA candidates with HCV. Many patients are faced with financial burdens, as insurance coverage of direct-acting antiviral therapies is inconsistent and varies by the patient's state of residence and specific treatment regimen. ¼: TJA candidates with HCV present health-care providers with a unique set of challenges, often encompassing economic, psychosocial, and complex medical concerns. Multidisciplinary care teams can be beneficial when caring for and optimizing this patient cohort. ¼: Management of HCV prior to elective TJA is associated with higher up-front costs but ultimately reduces long-term patient morbidity as well as associated direct and indirect health-care expenditures.


Assuntos
Hepatite C Crônica , Hepatite C , Antivirais/uso terapêutico , Artroplastia , Hepacivirus , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Humanos , Estudos Retrospectivos
11.
Curr Rev Musculoskelet Med ; 14(4): 272-281, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34216364

RESUMO

PURPOSE OF REVIEW: Proximal femur fractures are common traumatic injuries treated by orthopedic surgeons. Preparation and positioning for surgical intervention are critical in the proper management of proximal femur fractures. The purpose of this study was to review the current evidence on the various positioning options for patients and to highlight the principles and emerging techniques to help orthopedic surgeons treat this common injury. RECENT FINDINGS: Strategic patient positioning is key to the reduction and fixation of proximal femur fractures without complications. The use of intramedullary devices for the fixation of proximal femur fractures has led to an increased use of the modern fracture table. The fracture table should be used when surgeons are facile with its use to avoid significant complications. Recent best available evidence has suggested increased risk of malrotation associated with the use of the fracture table. The use of the radiolucent table offers the most flexibility, but limits surgeons as multiple assistants are needed to maintain reduction during fixation. Positioning for proximal femur fractures is an important technique for general and trauma orthopedic surgeons. Surgeons need to be aware of the various techniques for positioning of proximal femur fractures due to the diversity of injury patterns and patient characteristics. Each positioning technique has it benefits and potential complications that every orthopaedic surgeon should be familiar with while treating these injuries.

12.
JBJS Case Connect ; 11(2)2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-34010173

RESUMO

CASE: An 11-month-old boy was brought to the emergency department because he was refusing to use his right arm. X-rays demonstrated an anteroinferior Salter-Harris I fracture-dislocation of the proximal humeral epiphysis. Closed reduction with sedation was unsuccessful, so open reduction under general anesthesia was pursued. At 2 years, the patient has made a full recovery. CONCLUSION: Pediatric shoulder fracture-dislocations are rare. Clinicians must have a high index of suspicion for nonaccidental trauma when evaluating such injuries. When this injury is encountered in patients younger than 1 year, open reduction of the proximal humeral epiphysis can be a successful treatment option.


Assuntos
Fratura-Luxação , Luxação do Ombro , Fraturas do Ombro , Criança , Humanos , Lactente , Masculino , Redução Aberta , Ombro , Luxação do Ombro/diagnóstico por imagem , Luxação do Ombro/cirurgia , Fraturas do Ombro/diagnóstico por imagem , Fraturas do Ombro/cirurgia
13.
Sci Rep ; 11(1): 6535, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33753761

RESUMO

Distinguishing between direct and indirect frequency coupling is an important aspect of functional connectivity analyses because this distinction can determine if two brain regions are directly connected. Although partial coherence quantifies partial frequency coupling in the linear Gaussian case, we introduce a general framework that can address even the nonlinear and non-Gaussian case. Our technique, partial generalized coherence (PGC), expands prior work by allowing pairwise frequency coupling analyses to be conditioned on other processes, enabling model-free partial frequency coupling results. By taking advantage of recent advances in conditional mutual information estimation, we are able to implement our technique in a way that scales well with dimensionality, making it possible to condition on many processes and produce a partial frequency coupling graph. We analyzed both linear Gaussian and nonlinear simulated networks. We then performed PGC analysis of calcium recordings from mouse olfactory bulb glomeruli under anesthesia and quantified the dominant influence of breathing-related activity on the pairwise relationships between glomeruli for breathing-related frequencies. Overall, we introduce a technique capable of eliminating indirect frequency coupling in a model-free way, empowering future research to correct for potentially misleading frequency interactions in functional connectivity analyses.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Modelos Neurológicos , Animais , Encéfalo/diagnóstico por imagem , Eletroencefalografia , Humanos , Camundongos
14.
J Orthop ; 24: 126-130, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679037

RESUMO

Over the past two decades, oral health has emerged as a health care priority. Historically, patients greater than 65 years of age, the economically disadvantaged, members of racial or ethnic minority groups, or the disabled or home bound have experienced significant barriers to routine dental care. The connection between oral health care and periprosthetic joint infections (PJI) continues to be of importance to the orthopedic surgeon, as such infections are significantly morbid and costly. This review aims to introduce the importance of oral health as a small but crucial portion of an arthroplasty patient's overall perioperative management.

15.
J Neural Eng ; 18(4)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33684898

RESUMO

Objective. Accurate inference of functional connectivity is critical for understanding brain function. Previous methods have limited ability distinguishing between direct and indirect connections because of inadequate scaling with dimensionality. This poor scaling performance reduces the number of nodes that can be included in conditioning. Our goal was to provide a technique that scales better and thereby enables minimization of indirect connections.Approach. Our major contribution is a powerful model-free framework, graphical directed information (GDI), that enables pairwise directed functional connections to be conditioned on the activity of substantially more nodes in a network, producing a more accurate graph of functional connectivity that reduces indirect connections. The key technology enabling this advancement is a recent advance in the estimation of mutual information (MI), which relies on multilayer perceptrons and exploiting an alternative representation of the Kullback-Leibler divergence definition of MI. Our second major contribution is the application of this technique to both discretely valued and continuously valued time series.Main results. GDI correctly inferred the circuitry of arbitrary Gaussian, nonlinear, and conductance-based networks. Furthermore, GDI inferred many of the connections of a model of a central pattern generator circuit inAplysia, while also reducing many indirect connections.Significance. GDI is a general and model-free technique that can be used on a variety of scales and data types to provide accurate direct connectivity graphs and addresses the critical issue of indirect connections in neural data analysis.


Assuntos
Encéfalo , Modelos Neurológicos , Imageamento por Ressonância Magnética , Rede Nervosa , Redes Neurais de Computação
16.
J Arthroplasty ; 36(7S): S173-S178, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33483250

RESUMO

BACKGROUND: Same-day discharge (SDD) total joint arthroplasty (TJA) is increasingly popular, yet there remain concerns regarding patient safety, complication rates, and unforeseen overnight admission (failure to launch; FTL). The aim of this study is to retrospectively examine the outcomes of a large consecutive SDD-TJA series in the community hospital setting. METHODS: We retrospectively reviewed 1200 consecutive SDD-TJA candidates between March 2017 and December 2019 by 5 surgeons at a community hospital. Patient demographics, perioperative data including anesthesia type, and 30-day complications were evaluated, including FTL, infection, intraoperative fracture, postoperative periprosthetic fracture or dislocation, return to operating room, and unplanned postoperative care. RESULTS: We included 1200 SDD patients (582/618 total hip arthroplasty/total knee arthroplasty, mean age 62.1 years, 595 females, 605 males). Spinal anesthesia was more common than general anesthesia (1087 vs 113 patients). There were 85 FTLs (7.1%), of this cohort 58.8% were female, with a mean age of 62.4 years. General anesthesia increased the risk of FTL (odds ratio 2.93). Complications resulting in FTL included block-induced neuropraxia (32.1%), orthostatic hypotension (26.1%), urinary retention (19.0%), and nausea (13.1%). Sixteen patients were readmitted within 30 days (1.3%). Six patients returned to the operating room for periprosthetic fracture (4), wound dehiscence (1), and superficial surgical site infection (1). CONCLUSION: SDD-TJA can be safely performed at community hospitals, but general anesthesia should be avoided to decrease risk of FTL. Inpatient programs may allow young surgeons to gain experience with SDD-TJA while retaining overnight admission as a safety net for their patients. LEVEL OF EVIDENCE: Level III (Prognostic).


Assuntos
Artroplastia de Quadril , Hospitais Comunitários , Artroplastia de Quadril/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Complicações Pós-Operatórias , Estudos Retrospectivos
17.
Perm J ; 26(1): 11-20, 2021 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-35609161

RESUMO

INTRODUCTION: Effective, equity-promoting interventions implemented by health care systems are needed to address health care disparities and population-level health disparities. We evaluated the impact of a clinical decision support tool to improve evidence-based thiazide diuretic prescribing among Black patients to address racial disparities in hypertension control. METHODS: We employed an interrupted time series design and qualitative interviews to evaluate the implementation of the tool. Our primary outcome measure was the monthly rate of thiazide use among eligible patients before and after implementation of the tool (January 2013-December 2016). We modeled month-to-month changes in thiazide use for Black and White patients, overall, and by sex and medical center racial composition. We conducted key informant interviews to identify modifiable facilitators and barriers to implementation of the tool across medical centers. RESULTS: Of the 318,720 patients, 15.5% were Black. We observed no change in thiazide use or blood pressure control following the implementation of the tool in either racial subgroup. There was a slight but statistically significant reduction (2.32 percentage points, p < 0.01) in thiazide use among Black patients following the removal the tool that was not observed among White patients. Factors affecting the tool's implementation included physician and pharmacist resistance to thiazide use and a lack of ongoing promotion of the tool. DISCUSSION: The clinical decision support tool was insufficient to change prescribing practices and improve blood pressure control among Black patients. CONCLUSIONS: Future interventions should consider physician attitudes about thiazide prescribing and the importance of multilevel approaches to address hypertension disparities.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Prestação Integrada de Cuidados de Saúde , Hipertensão , Disparidades em Assistência à Saúde , Humanos , Hipertensão/tratamento farmacológico , Grupos Raciais , Tiazidas
18.
Sci Rep ; 10(1): 17372, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060626

RESUMO

Functional connectivity analyses focused on frequency-domain relationships, i.e. frequency coupling, powerfully reveal neurophysiology. Coherence is commonly used but neural activity does not follow its Gaussian assumption. The recently introduced mutual information in frequency (MIF) technique makes no model assumptions and measures non-Gaussian and nonlinear relationships. We develop a powerful MIF estimator optimized for correlating frequency coupling with task performance and other relevant task phenomena. In light of variance reduction afforded by multitaper spectral estimation, which is critical to precisely measuring such correlations, we propose a multitaper approach for MIF and compare its performance with coherence in simulations. Additionally, multitaper MIF and coherence are computed between macaque visual cortical recordings and their correlation with task performance is analyzed. Our multitaper MIF estimator produces low variance and performs better than all other estimators in simulated correlation analyses. Simulations further suggest that multitaper MIF captures more information than coherence. For the macaque data set, coherence and our new MIF estimator largely agree. Overall, we provide a new way to precisely estimate frequency coupling that sheds light on task performance and helps neuroscientists accurately capture correlations between coupling and task phenomena in general. Additionally, we make an MIF toolbox available for the first time.


Assuntos
Análise e Desempenho de Tarefas , Visão Ocular , Córtex Visual/fisiologia , Algoritmos , Animais , Macaca mulatta
19.
JBJS Rev ; 8(8): e20.00028, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32960028

RESUMO

Dislocation after total hip arthroplasty (THA) is the leading cause of revision surgery. Dual mobility (DM) implants have been utilized over the past 40 years as a means of addressing and preventing this morbid and expensive complication. Recently, there has been renewed investigation into the role that DM implants may play in reducing instability in high-risk patients. Hemiarthroplasty or traditional THA remain the mainstays of treatment for older patients with displaced femoral neck fractures. Longer-term higher-quality studies are necessary to investigate whether DM THA outcomes may be superior to traditional THA in the physiologically young patient with high physical demands and a longer-than-average life expectancy. The use of DM implants in preventing dislocation in patients with fixed spinopelvic alignment, neuromuscular disorders, and failed fixation of previously sustained proximal femoral fractures has shown success in studies with low levels of evidence. More robust prospective data are necessary before more widespread adoption of DM arthroplasty is recommended in these clinical scenarios. Knowledge of the pertinent literature with regard to the use of DM implants in patients who are at high risk for instability will allow orthopaedic surgeons to make informed decisions as to whether or not their patients may benefit from primary THA utilizing DM implants.


Assuntos
Artroplastia de Quadril/instrumentação , Luxação do Quadril/prevenção & controle , Prótese de Quadril , Complicações Pós-Operatórias/prevenção & controle , Artroplastia de Quadril/efeitos adversos , Luxação do Quadril/etiologia , Humanos , Complicações Pós-Operatórias/etiologia , Desenho de Prótese , Fatores de Risco
20.
JBJS Rev ; 8(9): e20.00030, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32890048

RESUMO

Developmental dysplasia of the hip (DDH) encompasses a wide spectrum of hip disorders, including neonatal instability, acetabular dysplasia, hip subluxation, and frank dislocation of the hip. It is a common disorder, with a reported incidence of between 0.1% and >10% of live births. Coordinated, interdisciplinary care is important to achieving successful outcomes. This starts with accurate assessment of risk factors in the prenatal period, thorough clinical examination by the primary care provider at all well-child visits, and early referral to a pediatric orthopaedic surgeon for prompt diagnosis and treatment. Early diagnosis and prompt treatment is critical for an excellent outcome. Ongoing, open communication between clinicians is essential for the effective coordination of care. Treatment options vary depending on the age of presentation. A Pavlik harness (dynamic hip abduction orthosis) is used for children up to 6 months of age. A more rigid abduction orthosis may be used if treatment with a Pavlik harness is unsuccessful, with a closed reduction and spica cast being the next step if needed for children up to 18 months of age. Finally, open reduction with possible concomitant femoral and/or pelvic osteotomies is the surgical option in an older child, when necessary. In general, the later the child is diagnosed with and treated for DDH, the greater the risk of a nonoptimal outcome. Depending on the severity of the condition, children with DDH may need to be followed closely until skeletal maturity so as not to miss the diagnosis of asymptomatic residual hip dysplasia, which can predispose patients to early hip arthritis.


Assuntos
Displasia do Desenvolvimento do Quadril/terapia , Equipe de Assistência ao Paciente , Braquetes , Displasia do Desenvolvimento do Quadril/diagnóstico por imagem , Feminino , Humanos , Recém-Nascido , Obstetrícia , Ortopedia , Pediatria , Período Periparto , Período Pós-Parto , Ultrassonografia
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