Quantitative Assessment of Abdominal Aortic Calcification and Disk Height Loss: The Framingham Study

Abstract Background context Vascular disease has been proposed as a risk factor for disc height loss (DHL). Purpose To examine the relationship between quantitative measures of abdominal aortic calcifications (AACs) as a marker of vascular disease, and DHL, on computed tomography (CT). Study design Cross-sectional study in a community-based population. Patient sample Four hundred thirty-five participants from the Framingham Heart Study. Outcome measures Quantitative AAC scores assessed by CT were grouped as tertiles of “no” (reference), “low,” and “high” calcification. Disc height loss was evaluated on CT reformations using a four-grade scale. For analytic purposes, DHL was dichotomized as moderate DHL of at least one level at L2–S1 versus less than moderate or no DHL. Methods We examined the association of AAC and DHL using logistic regression before and after adjusting for cardiovascular risk factors and before and after adjusting for age, sex, and body mass index (BMI). Results In crude analyses, low AAC (odds ratio [OR], 2.05 [1.27–3.30]; p=.003) and high AAC (OR, 2.24 [1.38–3.62]; p=.001) were strongly associated with DHL, when compared with the reference group of no AAC. Diabetes, hypercholesterolemia, hypertension, and smoking were not associated with DHL and did not attenuate the observed relationship between AAC and DHL. Adjustment for age, sex, and BMI markedly attenuated the associations between DHL and low AAC (OR, 1.20 [0.69–2.09]; p=.51) and high AAC (OR, 0.74 [0.36–1.53]; p=.42). Conclusions Abdominal aortic calcification was associated with DHL in this community-based population. This relationship was independent of cardiovascular risk factors. However, the association of AAC with DHL was explained by the effects of age, sex, and BMI

Presence and Extent of Severe Facet Joint Osteoarthritis Are Associated with Back Pain in Older Adults

Objective To determine whether the presence and extent of severe lumbar facet joint osteoarthritis (OA) are associated with back pain in older adults, accounting for disc height narrowing and other covariates. Design Two hundred and fifty-two older adults from the Framingham Offspring Cohort (mean age 67 years) were studied. Participants received standardized computed tomography (CT) assessments of lumbar facet joint OA and disc height narrowing at the L2–S1 interspaces using four-grade semi-quantitative scales. Severe facet joint OA was defined according to the presence and/or degree of joint space narrowing, osteophytosis, articular process hypertrophy, articular erosions, subchondral cysts, and intraarticular vacuum phenomenon. Severe disc height narrowing was defined as marked narrowing with endplates almost in contact. Back pain was defined as participant report of pain on most days or all days in the past 12 months. We used multivariable logistic regression to examine associations between severe facet joint OA and back pain, adjusting for key covariates including disc height narrowing, sociodemographics, anthropometrics, and health factors. Results Severe facet joint OA was more common in participants with back pain than those without (63.2% vs 46.7%; P = 0.03). In multivariable analyses, presence of any severe facet joint OA remained significantly associated with back pain (odds ratio (OR) 2.15 [95% confidence interval (CI) 1.13–4.08]). Each additional joint with severe OA conferred greater odds of back pain [OR per joint 1.20 (95% CI 1.02–1.41)]. Conclusions The presence and extent of severe facet joint OA on CT imaging are associated with back pain in community-based older adults, independent of sociodemographics, health factors, and disc height narrowing

Quantification of Walking Ability in Participants with Neurogenic Claudication from Lumbar Spinal Stenosis – A Comparative Study

Background context Walking limitations caused by neurogenic claudication (NC) are typically assessed with self-reported measures, although objective evaluation of walking using motorized treadmill test (MTT) or self-paced walking test (SPWT) has periodically appeared in the lumbar spinal stenosis (LSS) literature. Purpose This study compared the validity and responsiveness of MTT and SPWT for assessing walking ability before and after common treatments for NC. Study design Prospective observational cohort study. Patient sample Fifty adults were recruited from an urban spine center if they had LSS and substantial walking limitations from NC and were scheduled to undergo surgery (20%) or conservative treatment (80%). Outcome measures Walking times, distances, and speeds along with the characteristics of NC symptoms were recorded for MTT and SPWT. Self-reported measures included back and leg pain intensity assessed with 0 to 10 numeric pain scales, disability assessed with Oswestry Disability Index, walking ability assessed with estimated walking times and distances, and NC symptoms assessed with the subscales from the Spinal Stenosis Questionnaires. Methods Motorized treadmill test used a level track, and SPWT was conducted in a rectangular hallway. Walking speeds were self-selected, and test end points were NC, fatigue, or completion of the 30-minute test protocol. Results from MTT and SPWT were compared with each other and self-reported measures. Internal responsiveness was assessed by comparing changes in the initial results with the posttreatment results and external responsiveness by comparing walking test results that improved with those that did not improve by self-reported criteria. Results Mean age of the participants was 68 years, and 58% were male. Neurogenic claudication included leg pain (88%) and buttock(s) pain (12%). Five participants could not safely perform MTT. Walking speeds were faster and distances were greater with SPWT, although the results from both tests correlated with each other and self-reported measures. Of the participants, 72% reported improvement after treatment, which was confirmed by significant mean differences in self-reported measures. Motorized treadmill test results did not demonstrate internal responsiveness to change in clinical status after treatment but SPWT results did, with increased mean walking times (6 minutes) and distances (387 m). When responsiveness was assessed against external criterion, both SPWT and MTT demonstrated substantial divergence with self-reported changes in clinical status and alternative outcome measures. Conclusions Both MTT and SPWT can quantify walking abilities in NC. As outcome tools, SPWT demonstrated better internal responsiveness than MTT, but neither test demonstrated adequate external responsiveness. Neither test should be considered as a meaningful substitution for disease-specific measures of functio

Acute low back pain is marked by variability: An internet-based pilot study

<p>Abstract</p> <p>Background</p> <p>Pain variability in acute LBP has received limited study. The objectives of this pilot study were to characterize fluctuations in pain during acute LBP, to determine whether self-reported 'flares' of pain represent discrete periods of increased pain intensity, and to examine whether the frequency of flares was associated with back-related disability outcomes.</p> <p>Methods</p> <p>We conducted a cohort study of acute LBP patients utilizing frequent serial assessments and Internet-based data collection. Adults with acute LBP (lasting ≤3 months) completed questionnaires at the time of seeking care, and at both 3-day and 1-week intervals, for 6 weeks. Back pain was measured using a numerical pain rating scale (NPRS), and disability was measured using the Oswestry Disability Index (ODI). A pain flare was defined as 'a period of increased pain lasting at least 2 hours, when your pain intensity is distinctly worse than it has been recently'. We used mixed-effects linear regression to model longitudinal changes in pain intensity, and multivariate linear regression to model associations between flare frequency and disability outcomes.</p> <p>Results</p> <p>42 of 47 participants (89%) reported pain flares, and the average number of discrete flare periods per patient was 3.5 over 6 weeks of follow-up. More than half of flares were less than 4 hours in duration, and about 75% of flares were less than one day in duration. A model with a quadratic trend for time best characterized improvements in pain. Pain decreased rapidly during the first 14 days after seeking care, and leveled off after about 28 days. Patients who reported a pain flare experienced an almost 3-point greater current NPRS than those not reporting a flare (mean difference [SD] 2.70 [0.11]; p < 0.0001). Higher flare frequency was independently associated with a higher final ODI score (<it>ß </it>[SE} 0.28 (0.08); p = 0.002).</p> <p>Conclusions</p> <p>Acute LBP is characterized by variability. Patients with acute LBP report multiple distinct flares of pain, which correspond to discrete increases in pain intensity. A higher flare frequency is associated with worse disability outcomes.</p

Brief biopsychosocially informed education can improve insurance workers' back pain beliefs: Implications for improving claims management behaviours

Background: Biopsychosocially informed education is associated with improved back pain beliefs and positive changes in health care practitioners’ practice behaviours. Objective: Assess the effect of this type of education for insurance workers who are important non-clinical stakeholders in the rehabilitation of injured workers. Methods: Insurance workers operating in the Western Australian workers’ compensation system underwent two, 1.5 hour sessions of biopsychosocially informed education focusing on understanding and identifying barriers to recovery of injured workers with musculoskeletal conditions. Back pain beliefs were assessed pre-education, immediately post-education and at three-month follow-up (n = 32). Self-reported and Injury Management Advisor-reported assessment of change in claims management behaviours were collected at the three-month follow-up. Results: There were positive changes in the Health Care Providers’ Pain and Impairment Relationship Scale (p = 0.009) and Back Beliefs Questionnaire (p = 0.049) immediately following the education that were sustained at three-month follow-up. Positive changes in claims management behaviours were supported by self-reported and Injury Management Advisor-reported data. Conclusion: This study provides preliminary support that a brief biopsychosocially informed education program can positively influence insurance workers’ beliefs regarding back pain, with concurrent positive changes in claims management behaviours. Further research is required to ascertain if these changes result in improved claims management outcomes

Salinity and temperature balances at the SPURS central mooring during fall and winter

Author Posting. © The Oceanography Society, 2015. This article is posted here by permission of The Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 28, no. 1 (2015): 56-65, doi:10.5670/oceanog.2015.06.One part of the Salinity Processes in the Upper-ocean Regional Study (SPURS) field campaign focused on understanding the physical processes affecting the evolution of upper-ocean salinity in the region of climatological maximum sea surface salinity in the subtropical North Atlantic (SPURS-1). An upper-ocean salinity budget provides a useful framework for increasing this understanding. The SPURS-1 program included a central heavily instrumented mooring for making accurate measurements of air-sea surface fluxes, as well as other moorings, Argo floats, and gliders that together formed a dense observational array. Data from this array are used to estimate terms in the upper-ocean salinity and heat budgets during the SPURS-1 campaign, with a focus on the first several months (October 2012 to February 2013) when the surface mixed layer was becoming deeper, fresher, and cooler. Specifically, we examine the salinity and temperature balances for an upper-ocean mixed layer, defined as the layer where the density is within 0.4 kg m–3 of its surface value. The gross features of the evolution of upper-ocean salinity and temperature during this fall/winter season are explained by a combination of evaporation and precipitation at the sea surface, horizontal transport of heat and salt by mixed-layer currents, and vertical entrainment of fresher, cooler fluid into the layer as it deepened. While all of these processes were important in the observed seasonal (fall) freshening at this location in the salinity-maximum region, the variability of salinity on monthly-to-intraseasonal time scales resulted primarily from horizontal advection.J.T. Farrar, A.J. Plueddemann, J.B. Edson, and the deployment of the central mooring were supported by NASA grant NNX11AE84G. L. Rainville, C. Lee, C. Eriksen, and the Seaglider program were supported by NASA grant NNX11AE78G. R. Schmitt was supported by NSF grant OCE-1129646. B. Hodges and D. Fratantoni were supported by NASA grant NNX11AE82G. The Prawler moorings were funded by PMEL. The data analysis was also supported by NASA grant NNX14AH38G

Bias in the physical examination of patients with lumbar radiculopathy

<p>Abstract</p> <p>Background</p> <p>No prior studies have examined systematic bias in the musculoskeletal physical examination. The objective of this study was to assess the effects of bias due to prior knowledge of lumbar spine magnetic resonance imaging findings (MRI) on perceived diagnostic accuracy of the physical examination for lumbar radiculopathy.</p> <p>Methods</p> <p>This was a cross-sectional comparison of the performance characteristics of the physical examination with blinding to MRI results (the 'independent group') with performance in the situation where the physical examination was not blinded to MRI results (the 'non-independent group'). The reference standard was the final diagnostic impression of nerve root impingement by the examining physician. Subjects were recruited from a hospital-based outpatient specialty spine clinic. All adults age 18 and older presenting with lower extremity radiating pain of duration ≤ 12 weeks were evaluated for participation. 154 consecutively recruited subjects with lumbar disk herniation confirmed by lumbar spine MRI were included in this study. Sensitivities and specificities with 95% confidence intervals were calculated in the independent and non-independent groups for the four components of the radiculopathy examination: 1) provocative testing, 2) motor strength testing, 3) pinprick sensory testing, and 4) deep tendon reflex testing.</p> <p>Results</p> <p>The perceived sensitivity of sensory testing was higher with prior knowledge of MRI results (20% vs. 36%; p = 0.05). Sensitivities and specificities for exam components otherwise showed no statistically significant differences between groups.</p> <p>Conclusions</p> <p>Prior knowledge of lumbar MRI results may introduce bias into the pinprick sensory testing component of the physical examination for lumbar radiculopathy. No statistically significant effect of bias was seen for other components of the physical examination. The effect of bias due to prior knowledge of lumbar MRI results should be considered when an isolated sensory deficit on examination is used in medical decision-making. Further studies of bias should include surgical clinic populations and other common diagnoses including shoulder, knee and hip pathology.</p

From salty to fresh—salinity processes in the Upper-ocean Regional Study-2 (SPURS-2) : diagnosing the physics of a rainfall-dominated salinity minimum

Author Posting. © The Oceanography Society, 2015. This article is posted here by permission of The Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 28, no. 1 (2015): 150-159, doi:10.5670/oceanog.2015.15.One of the notable features of the global ocean is that the salinity of the North Atlantic is about 1 psu higher than that of the North Pacific. This contrast is thought to be due to one of the large asymmetries in the global water cycle: the transport of water vapor by the trade winds across Central America and the lack of any comparable transport into the Atlantic from the Sahara Desert. Net evaporation serves to maintain high Atlantic salinities, and net precipitation lowers those in the Pacific. Because the effects on upper-ocean physics are markedly different in the evaporating and precipitating regimes, the next phase of research in the Salinity Processes in the Upper-ocean Regional Study (SPURS) must address a high rainfall region. It seemed especially appropriate to focus on the eastern tropical Pacific that is freshened by the water vapor carried from the Atlantic. In a sense, the SPURS-2 Pacific region will be looking at the downstream fate of the freshwater carried out of the SPURS-1 North Atlantic region. Rainfall tends to lower surface density and thus inhibit vertical mixing, leading to quite different physical structure and dynamics in the upper ocean. Here, we discuss the motivations for the location of SPURS-2 and the scientific questions we hope to address

On multivariable Sheffer sequences

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23734/1/0000706.pd

A novel Big Data analytics and intelligent technique to predict driver's intent

Modern age offers a great potential for automatically predicting the driver's intent through the increasing miniaturization of computing technologies, rapid advancements in communication technologies and continuous connectivity of heterogeneous smart objects. Inside the cabin and engine of modern cars, dedicated computer systems need to possess the ability to exploit the wealth of information generated by heterogeneous data sources with different contextual and conceptual representations. Processing and utilizing this diverse and voluminous data, involves many challenges concerning the design of the computational technique used to perform this task. In this paper, we investigate the various data sources available in the car and the surrounding environment, which can be utilized as inputs in order to predict driver's intent and behavior. As part of investigating these potential data sources, we conducted experiments on e-calendars for a large number of employees, and have reviewed a number of available geo referencing systems. Through the results of a statistical analysis and by computing location recognition accuracy results, we explored in detail the potential utilization of calendar location data to detect the driver's intentions. In order to exploit the numerous diverse data inputs available in modern vehicles, we investigate the suitability of different Computational Intelligence (CI) techniques, and propose a novel fuzzy computational modelling methodology. Finally, we outline the impact of applying advanced CI and Big Data analytics techniques in modern vehicles on the driver and society in general, and discuss ethical and legal issues arising from the deployment of intelligent self-learning cars