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Background: Debilitating pain associated with knee osteoarthritis (OA) often leads patients to seek and complete total knee arthroplasty (TKA). To date, few studies have evaluated the relation of functional impairment to the risk of TKA, despite the fact that OA is associated with functional impairment. Questions/purposes: The purpose of our study was to (1) evaluate whether function as measured by WOMAC physical function subscale was associated with undergoing TKA; and (2) whether any such association varied by sex. Methods: The National Institutes of Health-funded Multicenter Osteoarthritis Study (MOST) is an observational cohort study of persons aged 50 to 79 years with or at high risk of symptomatic knee OA who were recruited from the community. All eligible subjects with complete data were included in this analysis. Our study population sample consisted of 2946 patients with 5796 knees; 1776 (60%) of patients were women. We performed a repeated-measures analysis using baseline WOMAC physical function score to predict the risk of TKA from baseline to 30 months and WOMAC score at 30 months to predict risk of incident TKA from 30 months to 60 months. We used generalized estimating equations to account for the correlation between two knees within an individual and across the two periods. We calculated relative risk (RR) of TKA over 30 months by WOMAC function using a score of 0 to 5 as the referent in multiple binomial regressions with log link. Results: Those with the greatest functional impairment (WOMAC scores 40–68; 62 TKAs in 462 knee periods) had 15.5 times (95% confidence interval [CI], 7.6–31.8; p

Chronic pain can have a major effect on both workers and the workplace. Collaboration among workers, occupational health nurses, and specialist providers is important for ongoing management of mechanism-based therapies for chronic pain. This article examines collaborative care issues relative to nerve stimulation and intrathecal drug delivery systems. [ABSTRACT FROM AUTHOR]

Smalls arms propellants (SAP) also known as canister powders are readily accessible and cost-effective materials that firearms enthusiasts can acquire for the legitimate assembly of ammunition. These attributes also make SAPs advantageous for the construction of improvised explosive devices (IEDs). Thus, there is a need to develop robust metrics for the characterization of propellants to provide investigative leads as well as for comparisons between known and recovered residues. The goal of this research was to investigate the utility of a high-throughput, non-destructive, and low-cost quantitative automated image analysis routine for the characterization and discrimination of SAP. For this project, 204 one-pound canisters of smokeless propellant (powder) were acquired from local and online sources. These samples represent nine manufacturers and 154 unique brands. From this set, five brands were selected to assess the intra- and inter-lot variability. Eight parameters, which encompass size- and shape-dependent metrics were measured for each sample. A total of ∼85,000 granules (∼680,000 measurements) were analyzed using linear discriminant analysis. A detailed assessment of the variables shows that the size-dependent metrics provide the greatest amount of sample discrimination. Overall accuracy of the method to correctly classify a test subset of data to the brand level is ∼84.72%. The results from this study provide a framework in which to interpret smokeless propellant micromorphometry in the context of intelligence purposes for initial stages of criminal investigations, and for traditional comparisons between known and unknown samples., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Aluminum (Al) powder is commonly encountered in improvised explosive devices (IEDs) as a metallic fuel due to its availability and low cost. Although available commercially in powder form, amateur bomb-makers also produce their own Al powder via simple methods found online. In order to provide investigative leads and forensic intelligence, it is important to evaluate not only the composition of homemade devices, but also to distinguish between the various forms of Al powder they contain. To achieve this goal, a method using automated microscopy in combination with statistical techniques has been demonstrated to have the potential to provide source discrimination and investigative leads in source attribution of Al powders in IEDs. The present research refined this method and investigated 59 industrially and amateurly produced Al powder sources with seven subsamples per source using two traditional linear discriminant analyses (LDA), one with a standard data split for training and testing, and another using leave-one-out cross-validation. Averaging the classification accuracies for the two LDA-based analyses, LDA has the ability to correctly classify 59.26%, 83.35%, and 80.69% of the samples based on their powder source, type, and production method, respectively. This classification accuracy represents a 3407%, 317%, and 61.38% increase in accuracy from random class assignment, respectively. Further, in most instances of incorrect data attribution to a particular source, the subsample has been misidentified with another sample of the same powder type or production method., (© 2021 American Academy of Forensic Sciences. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

There is a serious issue within the forensic science community, which even extends outside of the field. The role of the scientist in the investigation of crime has been increasingly confined to the laboratory, which has been accompanied by the conflation of the terms forensic science and criminalistics. This unfortunate situation has been festering for years. To make matters worse, the era of the proactive, problem-defining, criminalist (generalist) is waning, and possibly over. Present-day "criminalists" are treated as little more than reactive, protocol-constrained, laboratory technicians, with few, if any, consequential crime scene roles. In most cases, these "criminalists" merely respond to routine requests from prosecutors and police. The absence of science at the front end of forensic investigations, i.e., the scene, has resulted in biased, ineffective, inefficient, and/or erroneous outcomes with immediate and long-term societal impacts. To disentangle this imbroglio, we propose the use of another term, traceology, which has seen limited use worldwide except in the field of archaeology. With respect to criminalistics, this term has been previously proposed by Margot (20-21). Traceology is an historical science, dealing with the examination, analysis, and scientific interpretation of event traces (signs or remnants) of earlier activities. In this commentary, we define and redefine familiar, but ambiguous, terms and concepts with the hope of recapturing the essence of criminalistics (32), which we suggest is best termed traceology., (© 2021 American Academy of Forensic Sciences.)

Aluminum (Al) powders are commonly used in improvised explosive devices as metallic fuels, a component of explosive mixtures. These powders can be obtained readily from industrial-scale and consumer products, and produced using unsophisticated "kitchen chemistry" techniques. This research demonstrates the potential of automated particle micromorphometry for comparisons between known source and questioned Al powders recovered from IEDs, as well as for insight into the method of Al powder manufacture. Al powder samples were obtained from legitimate manufacturers, and 56 samples were produced "in-house" from Al-containing spray paints and ball-milled Al foils. Transmitted light microscope images of Al powder particles were acquired using an automated stage with automated z-focus; 17 size and shape parameters were measured for all particles. Approximately 37,000-2,500,000 particles/sample were analyzed using an open-source statistical package with customized code. Dimensionality reduction was required for processing the large datasets: eight of the 17 measured variables were selected based on inspection of the correlation matrix. Data from four subsamples from each of the 56 samples produced using "in-house" methods were analyzed using ANOVA to assess the within- and between-sample variation. High within-sample variation was noted; however, ANOVA and post-hoc Tukey's honestly significant difference (HSD) tests demonstrated that the between-sample variation was substantially larger than the within-sample variation. Each sample could be differentiated from all other samples in the test set. Future experiments will focus on ways to reduce the within-sample variation, and additional statistical and microanalytical methods to classify sources and confidently constrain the method of Al powder manufacture., (© 2020 American Academy of Forensic Sciences. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

A study was undertaken using nonhuman mammal specimens to better understand environmental influences on postmortem hair root band (PMRB) formation and to see whether PMRBs would occur in nonhuman mammal hairs in a similar fashion to human hairs. Carcasses from surrounding roadways were the primary source of specimens for this study, augmented by donated deceased domestic pets. Sections of pelt from each specimen were placed in controlled environmental conditions while the remainder of the carcass was left in a secure outdoor setting. Hair samples were collected daily from outdoor and control specimens and examined for evidence of PMRBs. Several environmental factors were also recorded on a daily basis. Results demonstrate PMRBs can occur in nonhuman mammal hairs, and they have microscopic characteristics similar to human PMRBs. Factors found to correlate with PMRB formation include postmortem interval, temperature, pH, and the formation and subsequent volatilization of ammonia from the surrounding tissue., (© 2018 American Academy of Forensic Sciences.)

A postmortem root band (PMRB) is a distinct microscopic feature that is postulated to occur in hair remaining in the follicle during the postmortem interval [1] (Petraco et al., 1998). The scientific validity of this premise has been highlighted in two recent high-profile criminal cases involving PMRBs [2,3] (State of Florida v. Casey Marie Anthony, 2008; People v. Kogut, 2005). To better understand the fundamental aspects of postmortem root banding, the microscopical properties of known PMRBs 1 were characterized by light microscopy, and scanning electron microscope (SEM) imaging of microtomed sections of hairs showing root banding. The results from this study show that the appearance of the PMRB may be due to the degradation of the chemically labile, non-keratin intermacrofibrillar matrix (IMM) in the pre-keratin/keratogenous region of anagen hairs. In addition, this degradation is confined to the cortex of the hair, with no apparent damage to the layers of the cuticle. These results could provide valuable information for determining the mechanism of band formation, as well as identify a set of microscopic features that could be used to distinguish hairs with known PMRBs from similarly looking environmentally degraded hairs., (Published by Elsevier Ireland Ltd.)

Objective: To examine the relationship between plantar stress over a step, cumulative plantar stress over a day, and first metatarsophalangeal (MTP) joint pain among older adults., Methods: Plantar stress and first MTP pain were assessed within the Multicenter Osteoarthritis Study. All included participants were asked if they had pain, aching, or stiffness at the first MTP joint on most days for the past 30 days. Pressure time integral (PTI) was quantified as participants walked on a pedobarograph, and mean steps per day were obtained using an accelerometer. Cumulative plantar stress was calculated as the product of regional PTI and mean steps per day. Quintiles of hallucal and second metatarsal PTI and cumulative plantar stress were generated. The relationship between predictors and the odds ratio of first MTP pain was assessed using a logistic regression model., Results: Feet in the quintile with the lowest hallux PTI had 2.14 times increased odds of first MTP pain (95% confidence interval [95% CI] 1.42-3.25, P < 0.01). Feet in the quintile with the lowest second metatarsal PTI had 1.50 times increased odds of first MTP pain (95% CI 1.01-2.23, P = 0.042). Cumulative plantar stress was unassociated with first MTP pain., Conclusion: Lower PTI was modestly associated with increased prevalence of frequent first MTP pain at both the hallux and second metatarsal. Lower plantar loading may indicate the presence of an antalgic gait strategy and may reflect an attempt at pain avoidance. The lack of association with cumulative plantar stress may suggest that patients do not limit their walking as a pain-avoidance mechanism., (© 2016, American College of Rheumatology.)

Fingerprint evidence can benefit in image quality if transformed using digital image processing techniques. This is especially true when considering prints that cannot be easily lifted (such as those deposited on porous paper substrates), or when the mechanism of lifting does not effectively reduce background interferences. In these instances, frequency filtering is one type of mathematical transformation that can serve to increase image clarity and the ability to extract minutiae relevant to pairwise comparisons. To quantify the impact of frequency filtering on image quality, high quality and low quality (noisy) prints were collected. The high quality prints served as exemplars that were compared to the low quality prints both pre- and post-filtering. The resulting pairwise match scores indicate that: (1) frequency filtering has a low probability of creating false positive associations, (2) 90% of the post-filtered images result in a normalized gain in match score, (3) frequency filtering doubled the probability of obtaining match scores greater than 30% (for the automated algorithm employed in this study), and (4) filtering can double the probability of obtaining 10 or more matching minutiae when comparing same source prints. Overall, the research indicates a reasonable and quantifiable payoff in increased clarity, matching minutiae and pairwise similarity for post-filtered images when compared to known-match exemplars., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Objective: Varus and valgus alignment are associated with progression of knee osteoarthritis, but their role in incident disease is less certain. Radiographic measures of incident knee osteoarthritis may be capturing early progression rather than disease development. The authors tested the hypothesis: in knees with normal cartilage morphology by MRI, varus is associated with incident medial cartilage damage and valgus with incident lateral damage., Methods: In MOST, a prospective study of persons at risk of or with knee osteoarthritis, baseline full-limb x-rays and baseline and 30-month MRI were acquired. In knees with normal baseline cartilage morphology in all tibiofemoral subregions, logistic regression was used with generalised estimating equations to examine the association between alignment and incident cartilage damage adjusting for age, gender, body mass index, laxity, meniscal tear and extrusion., Results: Of 1881 knees, 293 from 256 persons met the criteria. Varus versus non-varus was associated with incident medial damage (adjusted OR 3.59, 95% CI 1.59 to 8.10), as was varus versus neutral, with evidence of a dose effect (adjusted OR 1.38/1° varus, 95% CI 1.19 to 1.59). The findings held even excluding knees with medial meniscal damage. Valgus was not associated with incident lateral damage. Varus and valgus were associated with a reduced risk of incident lateral and medial damage, respectively., Conclusion: In knees with normal cartilage morphology, varus was associated with incident cartilage damage in the medial compartment, and varus and valgus with a reduced risk of incident damage in the less loaded compartment. These results support that varus increases the risk of the initial development of knee osteoarthritis.

Context: PTH therapy improves bone mineral density (BMD) and decreases fractures in postmenopausal osteoporosis, but cost and the burden of daily injections limit its use., Objective: We evaluated two novel approaches to the use of 6 months of PTH therapy over 2 yr., Design, Setting, Participants, and Interventions: We conducted a randomized, double-blinded trial of two combinations of daily PTH(1-84) and monthly ibandronate in 44 postmenopausal women with low bone mass. Participants received either 6 months of concurrent PTH and ibandronate, followed by 18 months of ibandronate (concurrent) or two sequential courses of 3 months of PTH followed by 9 months of ibandronate (sequential) over 2 yr., Main Outcome Measures: Bone turnover markers were measured. Areal and volumetric BMD were assessed by dual-energy x-ray absorptiometry and quantitative computed tomography, respectively., Results: Over 2 yr, areal BMD at the spine and hip increased similarly in both groups, with 7.5 and 8.2% increases in spine BMD in the concurrent and sequential arms, respectively (difference -0.6%, 95% confidence interval=-3.4-2.1%). Volumetric BMD also increased similarly between groups. With concurrent therapy, mean N-propeptide of type I collagen increased 75% between baseline and month 1 and then declined. With sequential therapy, the second 3-month PTH course increased N-propeptide of type I collagen markedly (209%), although to a lesser absolute degree than the first., Conclusions: Six months of PTH(1-84), used over 2 yr with a bisphosphonate in either of our dosing regimens increased BMD substantially. Short PTH courses may provide the benefits of anabolic osteoporosis therapy with reduced burden for patients.

Objective: We conducted a cross-sectional study to describe the prevalence of tibiofemoral joint space narrowing (JSN) in medial and lateral compartments and assess whether it differs by sex and ethnic groups, and, if it does, to what extent such a difference is accounted for by knee malalignment., Methods: The Multicenter Osteoarthritis Study is an observational study of persons ages 50-79 years with either symptomatic knee osteoarthritis or high risk of disease. Knee radiographs were assessed for JSN in each tibiofemoral compartment. Mechanical axis angle was measured using full-extremity films. We compared the proportion of knees with medial compartment JSN and with lateral JSN between men and women, as well as between whites and African Americans, using a logistic regression model adjusting for covariates (race or sex and body mass index, age, education, and clinic site). We used generalized estimating equations to account for correlation between 2 knees within a person., Results: Of 5,202 knees (2,652 subjects), 1,532 (29.5%) had medial JSN and 427 (8.2%) had lateral JSN. Lateral JSN was more prevalent in the knees of women than in men (odds ratio [OR] 1.9, 95% confidence interval [95% CI] 1.5-2.4) and was also higher in the knees of African Americans than in whites (OR 2.4, 95% CI 1.7-3.3). Further adjustment for malalignment attenuated the OR for sex but not the OR for race., Conclusion: Women and African Americans are more likely to have lateral JSN than men and whites, respectively. Valgus malalignment may contribute to the higher prevalence in women., (Copyright © 2012 by the American College of Rheumatology.)

Objective: To examine whether the consistency or persistence of knee pain, in addition to its severity, predicts incident total knee replacement (TKR)., Methods: The Multicenter Osteoarthritis Study (MOST) is a longitudinal study of persons aged 50 to 79 years with symptomatic knee osteoarthritis or at high risk of disease. Subjects were queried about the presence of knee pain on most days of the previous 30 days (i.e., frequent knee pain; FKP) at 2 timepoints: a telephone screen followed by a clinic visit (median separation 4 weeks). We defined a knee as having "consistent pain" if the subject answered positively to the FKP question at both timepoints, "inconsistent pain" if FKP was positive at only one timepoint, or as "no FKP" if negative at both. We examined the association between consistent FKP and risk of TKR using multiple binomial regression with generalized estimating equations., Results: In 3026 persons (mean age 63 yrs, mean body mass index 30.4), 2979 knees (50%) had no FKP at baseline, 1279 knees (21.5%) had inconsistent FKP, and 1696 knees (28.5%) had consistent FKP. Risk of TKR over 30 months was 0.8%, 2.6%, and 8.8% for knees with no, inconsistent, and consistent FKP, respectively. Relative risks of TKR over 30 months were 1.2 (95% CI 0.6-2.3) and 2.3 (95% CI 1.2-4.4) for knees with inconsistent and consistent FKP, compared with those without FKP. This association was consistent across each level of pain severity on the Western Ontario and McMaster Universities Osteoarthritis Index., Conclusion: Consistency of frequent knee pain is associated with an increased risk of TKR independently of knee pain severity.

Objective: Varus and valgus alignment increase medial and lateral tibiofemoral load. Alignment was associated with tibiofemoral osteoarthritis progression in previous studies; an effect on incident osteoarthritis risk is less certain. This study tested whether alignment influences the risk of incident and progressive radiographic tibiofemoral osteoarthritis., Methods: In an observational, longitudinal study of the Multicenter Osteoarthritis Study cohort, full-limb x-rays to measure alignment were acquired at baseline and knee x-rays were acquired at baseline and knee x-rays at baseline and 30 months. Varus alignment was defined as ≤178° and valgus ≥182°. Using logistic regression and generalised estimating equations, the associations of baseline alignment and incident osteoarthritis at 30 months (in knees without baseline osteoarthritis) and alignment and osteoarthritis progression (in knees with osteoarthritis) were examined, adjusting. For age, gender, body mass index, injury, laxity and strength, with neutral knees as referent., Results: 2958 knees (1752 participants) were without osteoarthritis at baseline. Varus (adjusted OR 1.49, 95% CI 1.06 to 2.10) but not valgus alignment was associated with incident osteoarthritis. 1307 knees (950 participants) had osteoarthritis at baseline. Varus alignment was associated with a greater risk of medial osteoarthritis progression (adjusted OR 3.59, 95% CI 2.62 to 4.92) and a reduced risk of lateral progression, and valgus with a greater risk of lateral progression (adjusted OR 4.85, 95% CI 3.17 to 7.42) and a reduced risk of medial progression., Conclusion: Varus but not valgus alignment increased the risk of incident tibiofemoral osteoarthritis. In knees with osteoarthritis, varus and valgus alignment each increased the risk of progression in the biomechanically stressed compartment.