Kickstand rods and correction of coronal malalignment in patients with adult spinal deformity

Purpose

Coronal malalignment (CM) is a challenging spinal deformity to treat. The kickstand rod (KR) technique is powerful for correcting truncal shift. This study tested the hypothesis that the KR technique provides superior coronal alignment correction in adult deformity compared with traditional rod techniques.

Methods

A retrospective evaluation of a prospectively collected multicenter database was performed. A 2:1 matched cohort of non-KR accessory rod and KR patients was planned based on preoperative coronal balance distance (CBD) and a vector of global shift. Patients were subgrouped according to CM classification with a 30-mm CBD threshold defining CM, and comparisons of surgical and clinical outcomes among groups was performed.

Results

Twenty-one patients with preoperative CM treated with a KR were matched to 36 controls. KR-treated patients had improved CBD compared with controls (18 vs. 35 mm, P < 0.01). The postoperative CBD did not result in clinical differences between groups in patient-reported outcomes (P ≥ 0.09). Eight (38%) of 21 KR patients and 12 (33%) of 36 control patients with preoperative CM had persistent postoperative CM (P = 0.72). CM class did not significantly affect the likelihood of treatment failure (postoperative CBD > 30 mm) in the KR cohort (P = 0.70), the control cohort (P = 0.35), or the overall population (P = 0.31).

Conclusions

Application of the KR technique to coronal spinal deformity in adults allows for successful treatment of CM. Compared to traditional rod techniques, the use of KRs did not improve clinical outcome measures 1 year after spinal deformity surgery but was associated with better postoperative coronal alignment.

     

Endophthalmitis after intravitreal injections versus cataract surgery: a 15-year cohort

To compare the clinical features, visual outcomes and causative organisms between endophthalmitis secondary to cataract surgery or to intravitreal injections (IVI). Meir Medical Center, Kfar Saba, Israel. Retrospective, non-randomized comparative chart review. Medical records of patients with proven or suspected endophthalmitis admitted to the Ophthalmology Department at Meir Medical Center 2/2002–2/2017 were reviewed. Clinical characteristics including presenting and final visual acuity (VA) outcomes, causative organisms and time to admission were assessed. Among 84 patients in our study, 35 had preceding cataract surgery and 12 had preceding IVI. The post-cataract group showed a significant improvement in VA following treatment with a presenting and final VA (logMar ± SD) of (1.80 ± 0.54 and 1.39 ± 0.65, P < 0.01) as opposed to the post-IVI group (1.72 ± 0.26 and 1.81 ± 0.32, P = 0.692), while most patients in the cataract group exhibited some degree of VA recovery (70.96%). Patients undergoing cataract surgery were divided into two separate groups; those who underwent cataract surgery in a private center and those operated at a public center. Patients undergoing surgery at a private medical center showed improvement in VA outcomes following treatment (1.80 ± 0.57 and 1.13 ± 0.66, P < 0.01) as opposed to those operated on at our public medical center. Overall, patients with endophthalmitis following cataract surgery had better visual outcomes and were more likely to show a VA improvement following treatment when compared with endophthalmitis following IVI. Final VA outcomes of patients with endophthalmitis after cataract surgery performed in a private center were better than those operated on and treated in a public medical center.     

Chromosomal localization of the callipyge gene in sheep (Ovis aries) using bovine DNA markers.

A mutation causing muscular hypertrophy, with associated leanness and improved feed efficiency, has been recently identified in domestic sheep (Ovis aries). Preliminary results indicate that an autosomal dominant gene may be responsible for this economically advantageous trait. We have exploited the conservation in sequence and chromosomal location of DNA markers across Bovidae to map the corresponding callipyge locus to ovine chromosome 18 using a battery of bovine chromosome 21 markers. Chromosomal localization of the ovine callipyge locus is the first step toward positional cloning of the corresponding gene.     

A waterborne outbreak of Norwalk-like virus among snowmobilers-Wyoming, 2001

In February 2001, episodes of acute gastroenteritis were reported to the Wyoming Department of Health from persons who had recently vacationed at a snowmobile lodge in Wyoming. A retrospective cohort study found a significant association between water consumption and illness, and testing identified Norwalk-like virus (NLV) in 8 of 13 stool samples and 1 well. Nucleotide sequences from the positive well-water specimen and 6 of the positive stool samples were identical. This multistrain NLV outbreak investigation illustrates the importance of NLV as a cause of waterborne illness and should encourage monitoring for NLVs in drinking water.     

Unraveling R0: Considerations for Public Health Applications

We assessed public health use of R₀, the basic reproduction number, which estimates the speed at which a disease is capable of spreading in a population. These estimates are of great public health interest, as evidenced during the 2009 influenza A (H1N1) virus pandemic.We reviewed methods commonly used to estimate R₀, examined their practical utility, and assessed how estimates of this epidemiological parameter can inform mitigation strategy decisions.In isolation, R₀ is a suboptimal gauge of infectious disease dynamics across populations; other disease parameters may provide more useful information. Nonetheless, estimation of R₀ for a particular population is useful for understanding transmission in the study population. Considered in the context of other epidemiologically important parameters, the value of R₀ may lie in better understanding an outbreak and in preparing a public health response.During the spring of 2009, the 2009 H1N1 influenza pandemic began in North America and quickly spread around the world, sparking great interest in potential mitigation strategies for the first influenza pandemic in more than 40 years. Research focused on interventions such as social distancing that could be applied before a specific monovalent H1N1 vaccine became available in the fall of 2009. During the initial wave of the 2009 H1N1 outbreak, teams of modelers from around the world gathered available data from Mexico to estimate several of the novel virus’s characteristics.1,2 Efforts focused on the rapid estimation of the basic reproduction number, or R₀, of this virus. R₀ is a theoretical parameter that provides some information regarding the speed at which a disease is capable of spreading in a specific population. First estimates were published online by early May 2009.1,2 Estimates of R₀ continue to be published from other countries and as more data become available.3–11As an indicator of the interest in publications concerning R₀, an early publication on the pandemic potential of the 2009 H1N1 strain by Fraser et al.1 has garnered 654 citations as of February 7, 2013. Although the influenza pandemic explains much of the recent interest in the basic reproduction number, this interest is not limited to the field of influenza. Web of Science searches on the terms “reproduction number” or “reproductive number” revealed that there have been 710 publications on this topic from 2009 through February 7, 2013, across various disciplines, with most articles being published in journals covering infectious diseases and mathematical modeling. Table A (available as a supplement to this article at http://www.ajph.org) shows breakdown by journal. If the search is expanded to include data from previous years, it is clear that there has been exponential growth by calendar year in the number of publications on this topic (Figure 1). Why is there such growing interest in R₀ among the disciplines interested in the dynamics of infectious diseases? To help better understand the interest in the basic reproduction number among public health officials, infectious disease researchers, and theoretical modelers, we reviewed the derivation of R₀ and its history.Open in a separate windowFIGURE 1—The number of publications regarding infectious disease and mathematical modeling as reported by Web of Science.Note. The figure was produced by searching Web of Science on the terms “reproduction number” or “reproductive number” and limiting the results to the fields of infectious diseases, mathematical computational biology, and applied mathematics. Clearly, interest in research regarding the basic reproductive number has risen dramatically since the 1990s. The number of publications in this area currently appears to be growing exponentially.We present a basic epidemiological compartmental model (a susceptible–infected–recovered or SIR model with S, I, and R representing the 3 compartments) described by Kermack and McKendrick.12 In this relatively simple model designed to describe epidemics, individuals start as susceptible to a particular pathogen and then progress to the other 2 compartments if infected. The model is defined by a system of 3 ordinary differential equations (ODEs):in which β is the transmission rate, γ is the recovery rate (or the inverse of the infectious period), and N is the total population size such that N = S + I + R. The standard model in equation 1 assumes no births or deaths. At the beginning of the outbreak or epidemic (t = 0) we assume the population is composed entirely of susceptible individuals and a single infectious individual. With this model, if the transmission rate exceeds the recovery rate (i.e., β/γ > 1), the disease will spread (dI/dt > 0). Alternatively, β/γ is the number of new infections per unit time multiplied by the time period of infectiousness, and describes the number of new infections resulting from the initially infected individual. In the presented case of the simple SIR model, the basic reproduction number (or ratio) equals β/γ.The scientific community largely underappreciated the implications of the Kermack–McKendrick model until the late 1970s, when Anderson and May13 used the model to study strategies for controlling infectious diseases. R₀ is a parameter of importance for gauging the disease dynamics because it indicates when an outbreak might happen based on the threshold value of 1.0. More generally, if the effective reproduction number R_e = R₀ × (S/N) is greater than 1.0, we predict that the disease continues its spread; the effective reproduction reflects the fact that, as proportion of susceptible individuals decreases (S/N), disease transmission slows. From this simple mathematical perspective, epidemiologists frequently consider the basic reproductive number one of the most vital parameters in determining whether an epidemic is “controllable.”14,15 The objective of any public health response during an influenza pandemic, for example, is to slow or stop the spread of the virus by employing mitigation strategies that either (1) reduce R₀ by changing the transmission rate (e.g., via school closure) or the duration of infectiousness (e.g., through antiviral use) or (2) reduce R_e by reducing the number of susceptible individuals (e.g., by vaccination).     

Using web‐based training to improve accuracy of blood pressure measurement among health care professionals: A randomized trial

Accurate blood pressure measurement is crucial for proper screening, diagnosis, and monitoring of high blood pressure. However, providers are not aware of proper blood pressure measurement skills, do not master all the appropriate skills, or miss key steps in the process, leading to inconsistent or inaccurate readings. Training in blood pressure measurement for most providers is usually limited to a one‐time brief demonstration during professional education coursework. The American Medical Association and the American Heart Association developed a 30‐minute e‐Learning module designed to refresh and improve existing blood pressure measurement knowledge and clinical skills among practicing providers. One hundred seventy‐seven practicing providers, which included medical assistants, nurses, advanced practice providers, and physicians, participated in a multi‐site randomized educational study designed to assess the effect of this e‐Learning module on blood pressure measurement knowledge and skills. Participants were randomized 1:1 to either the intervention or control group. The intervention group followed a pre‐post assessment approach, and the control group followed a test‐retest approach. The initial assessment showed that participants in both the intervention and control groups correctly performed less than half of the 14 skills considered necessary to obtain an accurate blood pressure measurement (mean scores 5.5 and 5.9, respectively). Following the e‐Learning module, the intervention group performed on average of 3.4 more skills correctly vs 1.4 in the control group (P < .01). Our findings reinforce existing evidence that errors in provider blood pressure measurements are highly prevalent and provide novel evidence that refresher training improves measurement accuracy.     

Impact of diabetes status on immunogenicity of trivalent inactivated influenza vaccine in older adults

Individuals with type 2 diabetes mellitus experience high rates of influenza virus infection and complications. We compared the magnitude and duration of serologic response to trivalent influenza vaccine in adults aged 50–80 with and without type 2 diabetes mellitus. Serologic response to influenza vaccination was similar in both groups: greater fold‐increases in antibody titer occurred among participants with lower pre‐vaccination antibody titers. Waning of antibody titers was not influenced by diabetes status.     

The Prevalence and Impact of Dental Anxiety Among Adult New Zealanders

ObjectiveTo describe the prevalence and impact of dental anxiety in the New Zealand adult population.MethodsSecondary analysis of data from the 2009 New Zealand national oral health survey. Dental anxiety was measured using the Dental Anxiety Scale (DAS).ResultsThe prevalence of dental anxiety was 13.3% (95% CI = 11.4, 15.6). On average, DAS scores were higher by 14% among females, lower among those in the oldest age group (55+), higher by 10% among those in the European/Other ethnic category, and higher by 10% among those residing in the most deprived neighbourhoods. Those who were dentally anxious had greater oral disease experience and were less likely to have visited a dentist within the previous 12 months. They also had poorer oral health-related quality of life, with the highest prevalence of OHIP-14 impacts observed in dentally anxious 35- to 54-year-olds.ConclusionsDental anxiety is a dental public health problem. It is an important contributor to poor oral health and care avoidance among New Zealanders. There is a need to develop both clinical and population-level interventions aimed at reducing the condition''s prevalence and impact.Key words: Dental anxiety, New Zealand, Quality of life, Dental utilisation