Co-exposures to trace elements and polycyclic aromatic compounds (PACs) impacts North American river otter (Lontra canadensis) baculum.

Environmental loadings of polycyclic aromatic compounds (PACs) and trace elements are increasing in areas with marked oil and gas extraction, such as in the Athabasca oil sands region, Alberta, Canada. Some of these chemicals are recognized as potent endocrine disrupting compounds (EDCs). The impacts of co-exposure to PACs and metals on free-ranging wildlife is of considerable concern. River otters (Lontra canadensis) are sentinel species of aquatic ecosystem health. The baculum (penile bone) is an important part of the reproductive system in otters that ensures successful copulation. Although baculum health is critical to male reproductive success and is sensitive to exposure to EDCs, there is no information available regarding the impact of PAC and metal exposures on measures of baculum health. River otter baculum and livers were dissected from carcasses obtained from the fur trade. Trace element and PAC analyses were carried out in liver with matching baculums subjected to dimensional analysis, bone mineral density (BMD) and mechanical loading testing. Trace elements and select PACs exhibited both protective and deleterious effects on baculum bone health metrics. Alkylated four ring PACs were negatively associated with baculum bone material properties (ex: C4-Chrysene and C4-pyrene). The same compounds have been shown to exhibit strong anti-androgenic activities. Few comparable studies exist related to contamination and adverse effects of PACs in wild terrestrial mammals. Baculum health metrics may be an important tool to include in biomonitoring studies as to date, there are limited means to assess male reproductive performance in wildlife biomonitoring programs.

Predicting recovery after lumbar spinal stenosis surgery: A protocol for a historical cohort study using data from the Canadian Spine Outcomes Research Network (CSORN).

Background: Symptomatic lumbar spinal stenosis (SLSS) is a condition in which narrowing of the spinal canal results in entrapment and compression of neurovascular structures. Decompressive surgery, with or without spinal fusion, is recommended for those with severe symptoms for whom conservative management has failed. However, significant persistent pain, functional limitations, and narcotic use can affect up to one third of patients postsurgery. Aims: The aim of this study will be to identify predictors of outcomes 1-year post SLSS surgery with a focus on modifiable predictors. Methods: The Canadian Spine Outcomes Research Network (CSORN) is a large database of prospectively collected data on pre- and postsurgical outcomes among surgical patients. We include participants with a primary diagnosis of SLSS undergoing their first spine surgery. Outcomes are measured at 12 months after surgery and include back and leg pain, disability (Oswestry Disability Index, ODI), walking capacity (ODI item 4), health-related quality of life, and an overall recovery composite outcome (clinically important changes in pain, disability, and quality of life). Predictors include demographics (education level, work status, marital status, age, sex, body mass index), physical activity level, smoking status, previous conservative treatments, medication intake, depression, patient expectations, and other comorbidities. A multivariate partial least squares model is used to identify predictors of outcomes. Conclusion: Study results will inform targeted SLSS interventions, either for the selection of best candidates for surgery or the identification of targets for presurgical rehabilitation programs.

Contexte: La sténose spinale lombaire symptomatique (SSL) est une affection dans laquelle le rétrécissement du canal rachidien entraîne le piégeage et la compression des structures neurovasculaires. La chirurgie décompressive, avec ou sans fusion vertébrale, est recommandée pour les personnes présentant des symptômes graves et pour lesquelles la prise en charge conservatrice a échoué. Cependant, une douleur persistante importante, des limitations fonctionnelles et l'usage de narcotiques peuvent affecter jusqu'à un tiers des patients après l'opération.Objectifs: Cette étude aura pour but d'identifier les prédicteurs de résultats un an après l'intervention chirurgicale de la sténose spinale lombaire symptomatique, en mettant l'accent sur les prédicteurs modifiables.Méthodes: Le Canadian Spine Outcomes Research Network (CSORN) est une vaste base de données de patients chirurgicaux collectées de manière prospective comprenant des données sur les résultats pré et postopératoires. Nous inclurons les participants ayant un diagnostic primaire de sténose spinale lombaire symptomatique, qui subissent leur première opération de la colonne vertébrale. Les résultats sont mesurés 12 mois après l'opération et comprennent les douleurs dorsales et aux jambes, le handicap (Oswestry Disability Index, ODI), la capacité de marche (ODI, point 4), la qualité de vie liée à la santé et un résultat composite de récupération globale (changements cliniquement importants dans la douleur, le handicap et la qualité de vie). Les prédicteurs comprendront des données démographiques (niveau d'éducation, situation professionnelle, état civil, âge, sexe, indice de masse corporelle), le niveau d'activité physique, le tabagisme, les traitements conservateurs antérieurs, la prise de médicaments, la dépression, les attentes des patients et d'autres comorbidités. Un modèle multivarié des moindres carrés partiels sera utilisé pour identifier les prédicteurs de résultats.Conclusion: Les résultats de l'étude serviront de base à des interventions ciblées en matière de sténose spinale lombaire symptomatique, soit pour la sélection des meilleurs candidats à la chirurgie, soit pour déterminer des cibles pour les programmes de réadaptation pré-chirurgicale.

Identification of good candidates for valgus bracing as a treatment for medial knee osteoarthritis.

Valgus unloader braces are a conservative treatment option for medial compartment knee osteoarthritis that aim to unload the damaged medial compartment through application of an external abduction moment. Patient response to bracing is highly variable, however. While some experience improvements in pain, function, and joint loading, others receive little to no benefit. The objective of this work was to analyze clinical measures and biomechanical characteristics of unbraced walking to identify variables that are associated with the mechanical effectiveness of valgus unloader bracing. Seventeen patients with medial knee osteoarthritis walked overground with and without a valgus unloader brace. A musculoskeletal model was used to estimate the contact forces in the medial compartment of the tibiofemoral joint and brace effectiveness was defined as the decrease in peak medial contact force between unbraced and braced conditions. Stepwise linear regression was used to identify clinical and biomechanical measures that predicted brace effectiveness. The final regression model explained 77% of the variance in brace effectiveness using two variables. Bracing was more effective for those with greater peak external hip adduction moments and for those with higher Kellgren-Lawrence grades, indicating more severe radiographic osteoarthritis. The hip adduction moment was the best predictor of brace effectiveness and was well correlated with several other measures indicating that it may be functioning as a "biomarker" for good bracing candidates. CLINICAL SIGNIFICANCE: The ability to predict good candidates for valgus bracing may improve issues of patient compliance and could enable the ability to train patients to respond better to bracing. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:351-356, 2018.

Assessing Inactivated Polio Vaccine Introduction and Utilization in Kano State, Nigeria, April-November 2015.

Background: Kano State, Nigeria, introduced inactivated polio vaccine (IPV) into its routine immunization (RI) schedule in March 2015 and was the pilot site for an RI data module for the National Health Management Information System (NHMIS). We determined factors impacting IPV introduction and the value of the RI module on monitoring new vaccine introduction. Methods: Two assessment approaches were used: (1) analysis of IPV vaccinations reported in NHMIS, and (2) survey of 20 local government areas (LGAs) and 60 associated health facilities (HF). Results: By April 2015, 66% of LGAs had at least 20% of HFs administering IPV, by June all LGAs had HFs administering IPV and by July, 91% of the HFs in Kano reported administering IPV. Among surveyed staff, most rated training and implementation as successful. Among HFs, 97% had updated RI reporting tools, although only 50% had updated microplans. Challenges among HFs included: IPV shortages (20%), hesitancy to administer 2 injectable vaccines (28%), lack of knowledge on multi-dose vial policy (30%) and age of IPV administration (8%). Conclusion: The introduction of IPV was largely successful in Kano and the RI module was effective in monitoring progress, although certain gaps were noted, which should be used to inform plans for future vaccine introductions.

Ipsilateral and contralateral foot pronation affect lower limb and trunk biomechanics of individuals with knee osteoarthritis during gait.

BACKGROUND: Lateral wedges have been suggested for the treatment of individuals with knee osteoarthritis, but it may have undesirable effects on the biomechanics of gait through increased foot pronation. This study investigated the effects of increased unilateral foot pronation on the biomechanics of individuals with knee osteoarthritis during gait. METHODS: Biomechanical data of twenty individuals with knee osteoarthritis were collected while they walked in three conditions: i) flat sandals; ii) wedged sandal on the knee osteoarthritis limb and flat sandal on the healthy limb; and iii) flat sandal on the osteoarthritis and wedged sandal on the healthy limb. Knee pain and comfort were evaluated. Principal Component Analysis followed by ANOVA was implemented to identify differences between conditions. FINDINGS: The wedged sandal on the osteoarthritis limb increased rearfoot eversion (P<0.001; ES=0.79); increased shank rotation range of motion (P<0.001; ES=0.70); reduced knee internal rotation moment (P<0.001; ES=0.83); reduced hip internal rotation moment (P=0.001; ES=0.66); increased ipsilateral trunk lean (P=0.031; ES=0.47); and increased trunk rotation range of motion (P=0.001; ES=0.69). Walking with the wedged sandal on the healthy limb increased hip (P=0.003; ES=0.61) and knee (P=0.002; ES=0.63) adduction moments. Individuals reported greater comfort walking with the flat sandals (P=0.004; ES=0.55). INTERPRETATION: Increased unilateral foot pronation of the knee osteoarthritis and healthy limbs causes lower limb and trunk mechanical changes that may overload the knee and the lower back, such as increased knee adduction moment, shank rotation and trunk lateral lean. Foot motion of both lower limbs should be evaluated and care must be taken when suggesting lateral wedges for individuals with knee osteoarthritis.

Increased unilateral foot pronation affects lower limbs and pelvic biomechanics during walking.

BACKGROUND: Increased unilateral foot pronation may cause biomechanical changes on the lower limbs during gait. We investigated the effects of increased unilateral foot pronation on the biomechanics of lower limbs and pelvis during gait. METHODS: Kinematic and kinetic data of 22 participants were collected while they walked wearing flat and laterally wedged sandals. Principal omponent analysis was used to compare differences between conditions. FINDINGS: Wearing the wedged sandal on the ipsilateral side increased ankle eversion moment (p<0.001; effect size=0.97); rearfoot eversion angle (p<0.001; effect size=0.76); shank internal rotation (p=0.009; effect size=0.53); increased and reduced knee internal rotation angle during early and late stance, respectively (p<0.001; effect size=0.89); increased femur internal rotation (p=0.005; effect size=0.90); reduced hip internal rotation moment during late stance (p=0.001; effect size=0.68); and increased pelvic ipsilateral drop (p=0.02; effect size=0.48) of the ipsilateral side. Wearing the wedged sandal on the contralateral side increased pelvic contralateral drop (p=0.001; effect size=0.63); hip adduction moment throughout stance (p=0.027; effect size=0.46); and increased and reduced the knee adduction moment in early and late stance, respectively (p<0.001; effect size=0.79). INTERPRETATION: The increased lower limb internal rotation caused by the wedged sandal reinforces the assumption that rearfoot eversion is coupled with shank internal rotation. The increased pelvic contralateral drop caused by the wedged sandal on the contralateral side may explain the increased hip and knee adduction moments on the ipsilateral side. Increased unilateral foot pronation causes biomechanical changes on both lower limbs that are associated with the occurrence of injuries.

Direct comparison of kinematic data collected using an electromagnetic tracking system versus a digital optical system.

The purpose of this study was to quantify the dynamic accuracy of kinematics measured by a digital optical motion analysis system in a gait analysis laboratory (capture volume approximately 20m(3)) compared to a standard range direct-current electromagnetic (EM) tracking device (capture volume approximately 1m(3)). This is a subset of a larger effort to establish an appropriate marker set for the optical system to quantify upperlimb kinematics simultaneously with gait, in comparison to previous studies of isolated upperlimb movements that have employed EM tracking devices. Rigid clusters of spherical reflective markers and EM sensors were attached to a mechanical articulator that mimicked three-dimensional joint rotations, similar to the elbow. As the articulator was moved through known ranges of motion (i.e. gold standard), kinematic data were collected simultaneously using both tracking systems. Both systems were tended to underestimate the range of motion; however, the application of post hoc smoothing and least-squares correction algorithms reduced these effects. When smoothing and correction algorithms were used, the magnitude of the mean difference between the gold standard and either the EM or optical system did not exceed 2 degrees for any of the compound motions performed. This level of agreement suggests that the measurements obtained from either system are clinically comparable, provided appropriate smoothing and correction algorithms are employed.