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Spatiotemporal gait kinematics and their variability are commonly assessed in clinical and laboratory settings to quantify fall risk. Although the Hawthorne effect, or modifications in participant behavior due to knowledge of being observed, has the potential to impact such assessments, it has received minimal attention in the study of gait—particularly gait variability. The purpose of this study was to quantify the Hawthorne effect on variability and central tendency measures of fall-related spatiotemporal gait parameters. Seventeen healthy young adults walked on a treadmill at a self-selected velocity for 2 minutes under covert evaluation (ie, without awareness of being evaluated) and 2 minutes under overt evaluation. The movement was recorded using motion capture technology, from which we calculated mean value and step-to-step variability (using standard deviation and mean absolute deviation) of step length, step width, percent double support, percent stance phase, and stride time. Although central tendencies were unaffected by evaluation type, four-of-five measures of variability were significantly lower during overt evaluation for at least one-of-two metrics. Our results suggest a Hawthorne effect on locomotor control. Researchers should be aware of this phenomenon when designing research studies and interpreting gait assessments.

Redistribution of mechanical output from the ankle to the hip during walking occurs with advanced age. Changes to tissues spanning the ankle may limit the joint from performing mechanical functions necessary to walk at fast speeds and older adults may redistribute work proximally to compensate. Older adults with Parkinson’s disease (PD) do not exhibit the distal-to-proximal redistribution and may therefore be limited in reaching fast walking speeds. We tested whether advanced aging, regardless of the presence of PD, limits the ability to increase motor-like behavior of the ankle as walking speed increases. We also tested whether healthy older adults—but not PD patients—would compensate for reduced motor-like behavior at the ankle with disproportionately larger mechanical redistributions at faster speeds. The 16 young, 16 older, and 8 PD-diagnosed adults walked at 0.8, 1.2, and 1.6 ms−1 on a treadmill. We used joint functional indexing to quantify motor-like behavior of the ankle and a hip-to-ankle mechanical work ratio to quantify mechanical redistribution. We found a significant group x speed interaction (p < 0.05) for motor-like behavior of the ankle, with younger adults increasing motor index more than the older and PD groups as walking speed increased. Contrary to our second hypothesis, we found a significant main effect of speed (p < 0.001) on redistribution ratios, indicating that all three groups decreased redistribution ratios as walking speed increased, but not a significant interaction.

Background and Purpose: Older adults with lower balance confidence demonstrate a reduced willingness to experience instability as the task of walking becomes more challenging (i.e., walking with a faster speed). However, the specific reason why is not known. The purpose of this study was to investigate the extent to which capacity of increasing walking speeds relates to the attentional requirements (i.e., automaticity) of walking. Methods: Sixteen young (31 ± 5.85 years) and 15 older participants (69 ± 3.04 years) began walking on a treadmill at 0.4 m/s, and speed was increased by 0.2 m/s until the participant either chose to stop or reached a speed of 2.0 m/s. Sixty steps were collected at steady-state speed for each walking trial. Kinematic data were collected, and the margin of stability in the anterior direction (MOSAP) at heelstrike was quantified for each step. The timed up and go (TUG) and TUG dual (TUGdual) task were performed, from which an automaticity index (TUG/TUGdual × 100) was calculated. Older individuals were grouped based on whether they did or did not complete all walking speeds (i.e., completers [n = 9] or noncompleters [n = 6]). The fastest walking speed attempted (FSA), automaticity index, and MOSAP were compared, and correlations were assessed between the FSA/MOSAP and the automaticity index. Results: A significant difference was identified in an average MOSAP at heelstrike between older completer and noncompleter groups (p < 0.001). Further, older adults with lower automaticity index choose to stop walking at lower speeds (p = 0.001). The FSA was positively correlated with the automaticity index (ρ = 0.81, p < 0.001). Finally, the average MOSAP at FSA and the automaticity index were also negatively correlated (r = −0.85, p < 0.001). Conclusion: Older adults with lower automaticity of walking choose to stop walking at speeds before they completed all walking speeds, which may relate with increased attentional demands required to maintain dynamic stability at higher walking speeds. Given that these were otherwise healthy adults, the combination of FSA and an automaticity of walking may help to identify individuals who should be considered for an assessment to identify walking problems.

Objective To explore the association between measures of obesity and measures of trip-induced fall risk among community-dwelling older adults. Design Case-control. Setting Gait laboratory. Participants Voluntary sample of 55 community-dwelling older adults (aged ≥65y; N=55) with body mass index (BMI) of 18.84-44.68 kg/m2. Interventions Not applicable. Main Outcome Measures Measures of obesity included 6 anthropometry-based measures (BMI; thigh, hip and waist circumferences; ratio of waist-to-hip circumference; index of central obesity) and 4 dual-energy x-ray absorptiometry–based measures (percentage trunk, leg, and total fat; fat mass index). Measures of risk of tripping during overground walking included median and interquartile range of toe clearance and area under the swing phase toe trajectory. Measures of trip recovery after a laboratory-induced trip included trunk angle and angular velocity at ground contact of the first recovery step, anteroposterior distance from stepping foot to center of mass at the same instant, and step time of the first recovery step. Results Risk of tripping was associated with waist-to-hip ratio and thigh circumference. After grouping participants by waist-to-hip ratio, those with high ratios (≥0.9 cm for men and ≥0.85 cm for women) exhibited significantly greater variability in toe clearance. Trip recovery was associated with hip circumference, thigh circumference, fat mass index, and total fat. After grouping participants by fat mass index, those with high indices (>9 kg/m2 for men and >13 kg/m2 for women) exhibited less favorable trunk kinematics after a laboratory-induced trip (Cohen d=0.84). Conclusions Waist-to-hip ratio and fat mass index may more closely relate to trip-induced fall risk than BMI among community-dwelling older adults.

Aim: Adherence to offloading devices for diabetic foot ulcers (DFU) is poor and postural instability influences adherence. Prior research suggests an ankle-high removable cast walker (RCW) in tandem with a contralateral shoe lift might increase users’ balance relative to a traditional knee-high RCW without a lift. This study compared compensatory responses to perturbations under both conditions. Methods: Twenty-five individuals (48% male; age: 68±8 years) with diabetic peripheral neuropathy participated. Participants completed trials under three conditions: bilateral standardized shoes, knee-high RCW, and ankle-high RCW with contralateral shoe lift. Stepping thresholds (ST) were assessed for two types of perturbations:1) From a stopped position, a treadmill rapidly accelerated at 3.5m/s² to reach a set peak-velocity and then decelerated and stopped. The smallest peak-velocity to elicit a step was identified as the ST. Participants were separately oriented on the treadmill to elicit anterior and lateral ST; 2) A waist mounted spring scale was pulled until a target load was reached, then the spring was rapidly released. ST was the lowest load necessary to force a step upon release. Anterior and posterior waist-pull perturbations were done.Participants also rated their stability in each footwear condition via a 10cm visual analog scale. Data analyses focused upon the primary comparison of the two offloading conditions. Results: The knee-high RCW resulted in significantly decreased ST for two of the four tests (treadmill anterior: mean difference .037m/s2, p=.048 and anterior waist-pull: mean difference 2.2lbs, p Conclusions: Future prospective studies should assesses whether the differences noted in this study translate into differences in RCW adherence by patients with DFU. Disclosure R.T.Crews: None. N.J.Rosenblatt: None. Funding National Institute of Diabetes and Digestive and Kidney Disease

BACKGROUND AND OBJECTIVE: To report the long-term anatomic and visual outcomes of patients with Stickler syndrome undergoing retinal detachment (RD) surgery. PATIENTS AND METHODS: Retrospective, interventional, consecutive case series of patients with Stickler syndrome undergoing RD repair from 1999 to 2017 at the Long Island Vitreoretinal Consultants, New York. Retinal attachment status and visual acuity (VA) at 1-year and last follow-up were assessed. RESULTS: Successful reattachment was achieved in 28 of 29 eyes (97%) with an average of 2.3 surgeries (including silicone oil removal surgeries). Redetachment after the first surgery occurred in 13 eyes (45%). Mean Snellen VA at initial presentation, 1-year follow-up, and last follow-up were 20/289, 20/118 ( P = .012), and 20/103 ( P = .022), respectively. CONCLUSIONS: Anatomic success can be achieved in most eyes. However, redetachments are common, and multiple surgeries are often required. Reasonable visual recovery is possible in many eyes. [ Ophthalmic Surg Lasers Imaging Retina. 2020;51:612–616.]

Contributory citizen science projects (hereafter "contributory projects") are a powerful tool for avian conservation science. Large-scale projects such as eBird have produced data that have advanced science and contributed to many conservation applications. These projects also provide a means to engage the public in scientific data collection. A common challenge across contributory projects like eBird is to maintain participation, as some volunteers contribute just a few times before disengaging. To maximize contributions and manage an effective program that has broad appeal, it is useful to better understand factors that influence contribution rates. For projects capitalizing on recreation activities (e.g., birding), differences in contribution levels might be explained by the recreation specialization framework, which describes how recreationists vary in skill, behavior, and motives. We paired data from a survey of birders across the United States and Canada with data on their eBird contributions (n = 28,926) to test whether those who contributed most are more specialized birders. We assigned participants to 4 contribution groups based on eBird checklist submissions and compared groups' specialization levels and motivations. More active contribution groups had higher specialization, yet some specialized birders were not active participants. The most distinguishing feature among groups was the behavioral dimension of specialization, with active eBird participants owning specialized equipment and taking frequent trips away from home to bird. Active participants had the strongest achievement motivations for birding (e.g., keeping a life list), whereas all groups had strong appreciation motivations (e.g., enjoying the sights and sounds of birding). Using recreation specialization to characterize eBird participants can help explain why some do not regularly contribute data. Project managers may be able to promote participation, particularly by those who are specialized but not contributing, by appealing to a broader suite of motivations that includes both appreciation and achievement motivations, and thereby increase data for conservation. Lay Summary center dot Contributory science projects have conservation and societal benefits, yet some projects struggle with participant retention. center dot Recreation specialization (a framework that describes individuals' degree of engagement in and commitment to an activity) uses three dimensions to classify recreationists: affective (psychological attachment to specific activities), behavioral (frequency of participation, prior experience, and equipment used), and cognitive (knowledge and skill about an activity). center dot We used survey data about involvement and preferences of birders in the U.S. and Canada to measure recreation specialization. We then combined these data with respondents' checklist contributions to eBird. center dot Individuals who had the highest scores for all three recreation specialization dimensions contributed the most checklists to eBird. center dot Participants motivated by achievement contributed more than those not motivated by achievement. Motivation by appreciation did not influence the number of contributions. Wildlife Habitat Canada; Canadian Wildlife Service; Government of Ontario; Government of New Brunswick; Alberta NAWMP; University of Alberta; Social Sciences & Humanities Research Council [435-2017-1352]; Environment & Climate Change Canada; Ducks Unlimited Canada Published version Funding for the Canadian portion of this study was provided by Wildlife Habitat Canada, Environment & Climate Change Canada, the Canadian Wildlife Service, Ducks Unlimited Canada, the Government of Ontario, the Government of New Brunswick, Alberta NAWMP, the University of Alberta, and the Social Sciences & Humanities Research Council (File #435-2017-1352).

Falls present a tremendous challenge to health care systems. This article reviews the literature from the previous 5 years (2014-2019) in terms of methods to assess fall risk and potential steps that can be taken to reduce fall risk for patients visiting podiatric clinics. With regard to assessing fall risk, we discuss the role of a thorough medical history and podiatric assessments of foot problems and deformities that can be performed in the clinic. With regard to fall prevention we consider the role of shoe modification, exercise, pain relief, surgical interventions, and referrals.

Background Low balance confidence is a prevalent yet overlooked issue among people who use lower limb prostheses (LLP) that can diminish community integration and quality of life. There is a critical need to develop rehabilitation programs that specifically target balance confidence in people who use LLP. Previous research has shown that multicomponent interventions including cognitive-behavioral therapy (CBT) techniques and exercise are feasible and effective for improving balance confidence in older adults. Therefore, a cognitive behavioral–physical therapy (CBPT) intervention was developed to target balance confidence and increase community integration in people who use LLP. Methods/design This randomized control trial will recruit 60 people who use LLP with low balance confidence. Participants will be randomized to the CBPT intervention condition or control condition. Discussion The trial is designed to test the effects of the CBPT intervention on balance confidence and functional mobility in lower limb prosthesis users by examining self-reported and objective measures of community integration and quality of life. The trial will also examine the relationship between changes in balance confidence and changes in community integration following participation in CBPT intervention. Additionally, through participant feedback, researchers will identify opportunities to improve intervention efficacy. Trial registration ClinicalTrials.gov, NCT03411148. Registration date: January 26, 2018.

Increased variation in interannual weather due to climate change can exert a powerful influence on the population dynamics of a species. Understanding the influence of severe weather is important for managing weather‐sensitive species. While best management practices target vital rates that are affected by weather, focusing on a single vital rate may not be sufficient if other vital rates are secondarily limiting. A comprehensive modeling framework to forecast future population dynamics while incorporating weather scenarios and vital rate variation within observed ranges that can be affected by management actions are necessary. A potential approach is to combine an integrated population model (IPM) with a population viability analysis (PVA) to generate novel insights about population dynamics. We used the northern bobwhite (Colinus virginianus), a rapidly declining gamebird sensitive to snowfall along the northern extents of the species' range, to demonstrate the utility of a coupled IPM‐PVA framework for projecting the response of a population to weather, management, and changes in vital rates. We created an IPM using two sources of count data spanning seven years, five years of winter survival data, and two years of breeding season demographics for a declining bobwhite population in southwestern Ohio during 2007–2015. Quasi‐extinction probability at the end of the decadal projection during 2019–2029 was 0.384–0.410 for mild, average, and severe winter weather scenarios. Quasi‐extinction probability declined to 0.326 with 20% improvement in nest success and summer survival rates. A concurrent 20% increase in winter survival further reduced quasi‐extinction probability to 0.263, which is a ˜36% reduction in quasi‐extinction probability compared with the baseline scenario with no changes in vital rates. These results suggest that long‐term viability of this population may depend on extensive management of winter habitat to improve survival but will also require management actions to improve fecundity after severe winters. Our modeling approach demonstrated how IPMs can be used to project population responses to future weather conditions and overcome some of the pitfalls of traditional PVA. The coupled framework presented here can serve as a tool for managers to make climate‐informed management decisions.

Residual limb wounds or ulcers are one of the most frequent skin problems reported by lower extremity prosthesis users. Healing often requires prosthesis disuse, which can logically impair physical functioning. However, there are limited data available to support this idea. We report the impact of prosthesis disuse by presenting assessments of balance, gait, physical activity, and balance confidence obtained on a case subject before experiencing a wound and following reintroduction to a well-fit prosthesis after wound-related prosthesis disuse. The case subject was a 76-year-old male who suffered a unilateral, transtibial amputation due to synovial sarcoma 13 years before. After presenting with a history of pain in the area of a chronic skin plaque, he received a punch biopsy, which resulted in 4 weeks of prosthesis disuse followed by 12 weeks of limited use before a final well-fitting socket was received. The following data were collected 24 weeks before the biopsy and 4 weeks after receiving the final well-fitting socket: Berg Balance Scale, L-test of walking, quantitative gait analysis, Activity-specific Balance Confidence Scale, and 1 week of community-based activity. Balance confidence decreased nearly 19%, walking speed decreased by 12%, and steps/day decreased by 19% following ∼4 months of prosthesis disuse/limited use; functional measures were not impacted. Lower balance confidence is not trivial as it can lead to activity avoidance and increased fall risk. Interventions to target balance confidence changes following prosthesis disuses may be important to minimize the impact of disuse on physical and mental well-being.

Background: Fall-risk assessments for patients with diabetes fail to consider reactive responses to balance loss. The purpose of this study was to assess the feasibility of using a simple clinical tool to evaluate the impact of diabetes and fall history on reactive balance in older adults. Methods: We recruited 72 older adults with and without diabetes. Postural perturbations were applied by a waist-mounted spring scale. Stepping thresholds (STs) in the anterior and posterior directions were defined as the lowest spring-loads that induced a step. Balance was assessed via the National Institutes of Health Toolbox Standing Balance Test, and lower extremity sensation was assessed using vibratory perception threshold and Semmes-Weinstein monofilaments. Fall history over the past year was self-reported. Cox regressions and analysis of variance were used to compare hazard rates for stepping and observed STs between groups. Results: Anterior STs were elicited in 42 subjects and posterior STs in 65 subjects. Hazard rates for posterior ST were significantly affected by diabetes, with greater hazards for fallers with diabetes versus control fallers and nonfallers, after accounting for balance and sensory loss. For those who stepped, ST was lower in the posterior direction for the diabetes group. Additionally, anterior but not posterior ST was lower in all fallers vs all nonfallers. Conclusions: The waist-mounted spring scale is a clinically implementable device that can assess ST in older adults with diabetes. Using the device, we demonstrated that ST was affected by diabetes and could potentially serve as a fall-risk factor independent of balance or sensory loss.

OBJECTIVE The long-term morbidity associated with isolated left-sided congenital diaphragmatic hernia (CDH) has been described previously. However, antenatal criteria impacting gastrointestinal morbidity (GIM) are not yet defined. The objective of this study was to evaluate the effect of fetal stomach position on the risk of GIM at 2 years of age in children with left-sided CDH. METHODS This was a retrospective, observational multicenter cohort study of data obtained from January 2010 to January 2014, that included patients whose fetus had isolated left-sided CDH, with or without fetal endoscopic tracheal occlusion (FETO). Prenatal maternal, fetal and pediatric data were collected. Fetal stomach position was evaluated a posteriori by two observers, using ultrasound images at the level of the four-chamber view of the heart that had been obtained to calculate the observed-to-expected lung-area-to-head-circumference ratio (O/E-LHR). Fetal stomach position was graded as follows: Grade 1, stomach not visualized; Grade 2, stomach visualized anteriorly, next to the apex of the heart, with no structure in between the stomach and the sternum; Grade 3, stomach visualized alongside the left ventricle of the heart, and abdominal structures anteriorly; or Grade 4, as Grade 3 but with stomach posterior to the level of the atrioventricular heart valves. The primary outcome was GIM at 2 years of age, assessed in a composite manner, including the occurrence of gastroesophageal reflux disease, need for gastrostomy, duration of parenteral and enteral nutrition and persistence of oral aversion. Regression analysis was performed in order to investigate the effect of O/E-LHR, stomach position and FETO on various GIM outcome variables. RESULTS Forty-seven patients with fetal left-sided CDH were included in the analysis. Thirteen (27.7%) infants did not meet the criterion of exclusive oral feeding at 2 years of age. Fetal stomach position grade was associated significantly and independently with the duration of parenteral nutrition (odds ratio (OR), 19.86; P = 0.031) and persistence of oral aversion at 2 years (OR, 3.40; P = 0.006). On multivariate analysis, O/E-LHR was predictive of the need for prosthetic patch repair, but not for GIM. FETO did not seem to affect the risk of GIM at 2 years. CONCLUSION In isolated left-sided CDH, fetal stomach position is the only factor that is predictive of GIM at 2 years of age. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Falls present a tremendous challenge to health care systems. This article reviews the literature from the previous 5 years (2014-2019) in terms of methods to assess fall risk and potential steps that can be taken to reduce fall risk for patients visiting podiatric clinics. With regard to assessing fall risk, we discuss the role of a thorough medical history and podiatric assessments of foot problems and deformities that can be performed in the clinic. With regard to fall prevention we consider the role of shoe modification, exercise, pain relief, surgical interventions, and referrals.

Motor flexibility, the ability to employ multiple motor strategies to meet task demands, may facilitate ambulation in complex environments that constrain movements; loss of motor flexibility may impair mobility. The purpose of this study was to determine the effects of obesity (a specific model of mobility impairment) and advanced age on motor flexibility during a task that constrained foot placement while walking. Twenty-one community-dwelling obese (OB) and 25 normal weight (NW) older adults (46 total older adults-OA) and 10 younger adults (YA) walked normally on a treadmill (baseline) then walked while stepping on lighted cues projected onto the treadmill at locations corresponding to average foot placement during normal walking (cued). The uncontrolled manifold (UCM) analysis was used to partition total variance in a set of seven lower-limb segment angles into components that did ("bad" variance) and did not ("good" variance) affect step-to-step variance in the trajectory of the swing foot. Motor flexibility was operationalized as an increase (baseline to cued) in total variance with an increase in good variance that exceeded the change in bad variance. There was no significant group × walking task interaction for total and good variance for OB vs NW, but there was a strong and significant interaction effect for OA vs YA (p 0.01; Cohen's d 1.0). Whereas YA reduced both good and bad variance, OA increased good variance beyond the change in bad variance. In OA, these changes were associated with several functional measures of mobility. Cued walking may place greater demands on OA requiring greater reliance on motor flexibility, although otherwise healthy older obese adults may be able to compensate for functional and cognitive declines associated with obesity by increasing motor flexibility under such tasks. The extent to which motor flexibility is employed during novel or constrained tasks may be a biomarker of healthy aging and a target for (re)habilitation.

BackgroundThe Dachshund is a chondrodystrophic breed of dog predisposed to premature degeneration and calcification, and subsequent herniation, of intervertebral discs (IVDs). This condition is heritable in Dachshunds and breeding candidates are screened for radiographically detectable intervertebral disc calcification (RDIDC), a feature of advanced disc degeneration and a prognostic factor for clinical disease. RDIDC scoring has been previously shown to be consistent within scorers; however, strong scorer effect (subjectivity) was also reported. The aim of this study was to estimate the within- and between-scorer agreement (repeatability and reproducibility, respectively) of computed tomography (CT) scanning and magnetic resonance imaging (MRI) for scoring IVD calcification, and to compare these modalities with radiographic scoring.ResultsTwenty-one Dachshund dogs were screened for IVD calcification using the three imaging modalities. Three scorers scored each case twice, independently. Repeatability was highest for radiography (95.4%), and significantly higher than for CT (90.4%) but not MRI (93.8%). Reproducibility was also highest for radiography (92.9%), but not significantly higher than for CT or MRI (89.4% and 86.4%, respectively). Overall, CT scored IVDs differently than radiography and MRI (64.8% and 62.7% agreement, respectively), while radiography and MRI scored more similarly (85.7% agreement).ConclusionsDespite high precision for radiography, previous evidence of scorer subjectivity was confirmed, which was not generally observed with CT and MRI. The increased consistency of radiography may be related to prior scorer experience with the modality and RDIDC scoring. This study does not support replacing radiography with CT or MRI to screen for heritable IVD calcification in breeding Dachshunds; however, evaluation of dog-level precision and the accuracy of each modality is recommended.

A complete, but fractured and crushed, echinoid corona from early to middle Miocene of Sarawak, Malaysia, is described as a new species, Clypeaster sarawakensis nov. sp. Although similar to modern C. rarispinus, the new species shows a distinct set of characters including petal length, periproct position and gut coiling. The discovery of a new Clypeaster, a genus characterised by a high preservation potential, illustrates that little is known about echinoid evolution and diversification in the Central Indo-Pacific, which features as a biodiversity hotspot since the Oligocene. Besides describing Clypeaster sarawakensis, we also compiled the known Central Indo-Pacific echinoid fossil record and used it to examine the Cenozoic diversity of echinoids. The overall diversity throughout the Cenozoic, and especially the rapid diversity increase at the Oligocene–Miocene boundary, corresponds to diversity trends observed in other taxa from the region.

We describe herein the clinical, endoscopic, computed tomography (CT), pathologic, and microbiologic features of an infection caused by an under-recognized fungal pathogen, Flavodon flavus, in a 25-y-old Australian Quarter Horse. The horse had a unilateral obstructive nasal mass, resulting in stertor and dyspnea. On endoscopy, the mass was tan, multinodular, and completely obstructed the nasal passage. CT analysis revealed a large, soft tissue–attenuating and partially mineralized mass in the right nasal passage and dorsal-conchofrontal sinus, expanding into adjacent paranasal sinuses with associated bone lysis and rhinosinusitis. Histopathology of the mass on 2 occasions revealed suppurative inflammation initially, and pyogranulomatous inflammation subsequently. The inflammatory reaction surrounded numerous spherical fungal structures (~60–80 µm diameter) that stained positively on periodic acid–Schiff and Grocott methenamine silver stains. PCR for the fungal internal transcribed spacer 1 and 2 regions followed by Sanger sequencing on a cultured isolate identified the agent as F. flavus, which has only been reported previously as pathogenic in one horse in the United States, to our knowledge. Previous reports described this fungus as a nonpathogenic, environmental commensal fungus associated with insects and plants.

Informed consent usually provides foreknowledge of experimental methods that can potentially increase expectation of stimuli and, therefore, influence the response. We determined the effects of increased expectation and trip-specific training on the recovery response following a treadmill-delivered, trip-specific disturbance. To deliver unexpected disturbances, subjects were deceived during the informed consent process. The primary hypothesis was that the recovery response following an expected postural disturbance would be characterized by trunk kinematics that have been shown to decrease the likelihood of a fall, compared to following an unexpected postural disturbance. We further hypothesized that following an unexpected postural disturbance, the recovery response of the subjects who had completed a trip-specific training protocol would be more biomechanically favorable to recovery compared to those of subjects who had not received the training.Young adults were randomized into Untrained or Trained groups. During the informed consent process, the purpose of the study was explained to subjects in both groups as being to determine the effect of trip-specific training on postural sway while performing an attention-demanding task. Untrained subjects completed two trials during which they minimized their postural sway. During the second trial, an unexpected disturbance was delivered while they performed the attention-demanding task. Trained subjects performed a pre-training postural sway trial, followed by the delivery of a series of expected, training disturbances. Finally, an unexpected disturbance was delivered while they minimized postural sway and performed the attention-demanding task.Expectation significantly improved trunk kinematics (p .05). In addition, participation in the trip-specific training protocol following the unexpected disturbance the trunk kinematics of the Trained subjects were more biomechanically favorable to recovery than those of the Untrained subjects (p .01).Improved trunk kinematics following trip-specific training may be independent of the extent to which the disturbance is expected.

Diabetic foot ulcers (DFU) are a substantial dilemma for geriatric individuals with diabetes. The breakdown in tissue associated with DFU is typically a result of repetitive cycles of physical stress placed on the feet during weight-bearing activity. Accordingly, a key tenet in healing as well as preventing DFU is the use of offloading footwear to redistribute physical stress away from high stress locations such as bony prominences. Over the last several years there has been a substantial amount of effort directed at better understanding and implementing the practice of offloading. A review of this work as well as relevant technological advances is presented in this paper. Specifically, we will discuss the following topics in association with offloading diabetic feet: achieving optimal offloading, dosing activity/physical stress, thermal monitoring to detect preulcerative tissue damage, adherence with offloading devices, and optimizing the user experience. In addition to presenting progress to date, potential directions for further advancement are discussed.

Individuals with transtibial amputation are at increase risk of falling. The absence of an ankle joint and the associated musculature in these individuals can reduce clearance between the prosthetic foot and ground during the swing phase of gait, which may increase the risk of stumbling and in turn falling.To associate minimum toe clearance during gait in the laboratory with community-based, trip-related stumbles by individuals with transtibial amputation using conventional feet.Prospective cohort design; following quantitative gait analysis, participants completed electronic surveys to prospectively report stumbles and falls for 1 year thereafter.General community with gait analysis conducted within a motion analysis laboratory and prospective tracking of stumbles occurring in the community. A volunteer sample of eight unilateral, transtibial amputees that were K3 or K4 level ambulators and current patients at a local prosthetic clinic. All participants completed the entire 1-year follow-up study. Prosthetic-side minimum toe clearance while walking on a level treadmill at self-selected speed and self-reported trip-related stumbles in the community. Minimum toe clearance was defined as a local minimum of the vertical displacement of the toe from toe-off to heelstrike relative to its position during midstance.Prosthetic-side minimum toe clearance was more than 50% lower for participants who reported one or more trip-related stumbles on that side compared with participants who reported zero trip-related stumbles on the prosthetic side (minimum toe clearance = 12.3 ± 0.8 mm vs 25.6 ± 5.4 mm, respectively; p = 0.036).This is the first study relating laboratory-based measures to prospective stumbles by prosthesis users. The results suggest that prosthesis users with low minimum toe clearance may be at increased risk of experiencing a trip-related stumble in the community. Given that frequent stumbling increases the risk of falling, future work is warranted on the effectiveness of interventions focused on minimum toe clearance on reducing fall risk. Clinical relevance Interventions to increase minimum toes clearance, which could include prescription of active dorsiflexing prostheses or gait training, may help reduce the risk of trip-related falls for individuals who report a history of trip-related stumbles.

Case report A 6-week-old Thoroughbred filly was presented for evaluation of an expansile mass overlying the right nasal passage and causing respiratory stertor. On skull radiographs, there was a loculated, soft tissue-opaque mass identified dorsal to the right upper premolars and effacing the right nasal cavity. Computed tomography (CT) revealed a locally extensive mass with relatively benign characteristics located centrally on the tooth root apices of the deciduous second premolar (506). The mass extended axially into the right nasal cavity, occluding the meatuses and causing displacement of the nasal septum to the left. Clinical outcome & significance Surgical excision was not deemed feasible with an athletic future in mind and the owners elected to euthanase the filly. Histopathologically, the mass was consistent with unicystic ameloblastoma and was lined intermittently with palisading, columnar basal cells (ameloblast-like cells) overlying a zone containing stellate cells in loose stroma. To the authors’ knowledge this is the first report of a CT scan of an equine ameloblastoma. Although histopathology was essential for definitive diagnosis, CT clearly defined the origin of the mass and identified its locally extensive, cystic nature, which enabled informed decisions to be made.

Objectives Diffusion weighted magnetic resonance imaging (DWI) is a sensitive method to assess brain maturation or detect brain lesions, providing Apparent Diffusion Coefficient (ADC) values as a measure of water diffusion. Abnormal ADC values are seen in ischemic brain lesions, such as acute or chronic hypoxia. The aim of this study was to assess whether ADC values in the fetal brain were different in a group of fetuses exposed to severe vascular intrauterine growth restriction, compared to normal controls. Methods We compared 30 severe intra-uterine growth restricted fetuses (IUGR

Obesity increases fall risk, and fall-related injuries in older adults. While prior work suggests obesity influences postural stability during standing, little is known about how obesity affects walking stability. Therefore, this study compared walking stability in older adults with and without obesity. Exploratory analyses were also conducted to evaluate the associations between measures of body habitus and gait stability as well as the association between prospective stumbles and falls and gait stability. A total of 34 older adults (17 with obesity, 17 with normal weight) walked on a treadmill at a self-selected speed. Walking stability was quantified as the local dynamic stability of the trunk in all three planes of motion. Participants also performed a series of functional tests, and were followed for a one-year period during which they reported falls and stumbles. Although participants with obesity performed significantly worse than participants without obesity on most functional tests, there were no differences in stability between groups in any direction (p = 0.18–0.78; η2 = 0.003–0.056), nor between those with and without a prospective fall or stumble (p = 0.18–0.93; η2 = 0.003–0.054). There were significant, albeit weak, correlations between BMI, waist circumference, and waist-to-height ratio and walking instability (p = 0.027–0.042; ρ = 0.36–0.39). Increased body mass, in absence of other obesity-related comorbidities, may have minimum impact on walking stability and in turn fall risk in older adults.

OBJECTIVE To measure prospectively apparent diffusion coefficient (ADC) values between 28 and 32 weeks of gestation in different cerebral territories of fetuses with estimated fetal weight (EFW) ≤ 5th centile, and analyze their association with adverse perinatal outcome. METHODS This was a prospective study involving six tertiary-level perinatal centers. In the period 22 November 2016 to 11 September 2017, we included singleton, small-for-gestational-age (SGA) fetuses with EFW ≤ 5th percentile, between 28 and 32 weeks of gestation, regardless of the umbilical artery Doppler and maternal uterine artery Doppler findings. A fetal magnetic resonance imaging (MRI) examination with diffusion-weighted sequences (DWI) was performed within 14 days following inclusion and before 32 weeks. ADC values were calculated in the frontal and occipital white matter, basal ganglia and cerebellar hemispheres. An ultrasound examination was performed within 1 week prior to the MRI examination. The primary outcome was a composite measure of adverse perinatal outcome, defined as any of the following: perinatal death; admission to neonatal intensive care unit with mechanical ventilation > 48 h; necrotizing enterocolitis; Grade III-IV intraventricular hemorrhage; periventricular leukomalacia. A univariate comparison of median ADC values in all cerebral territories between fetuses with and those without adverse perinatal outcome was performed. The association between ADC values and adverse perinatal outcome was then analyzed using multilevel logistic regression models to adjust for other common prognostic factors for growth-restricted fetuses. RESULTS MRI was performed in 64 patients, of whom five were excluded owing to fetal movement artifacts on DWI and two were excluded for termination of pregnancy with no link to fetal growth restriction (FGR). One intrauterine death occurred secondary to severe FGR. Among the 56 liveborn neonates, delivered at a mean ± SD gestational age of 33.6 ± 3.0 weeks, with a mean birth weight of 1441 ± 566 g, four neonatal deaths occurred. In addition, two neonates required prolonged mechanical ventilation, one of whom also developed necrotizing enterocolitis. Overall, therefore, seven out of 57 (12.3%) cases had an adverse perinatal outcome (95% CI, 3.8-20.8%). The ADC values in the frontal region were significantly lower in the group with adverse perinatal outcome vs those in the group with favorable outcome (mean values of both hemispheres, 1.68 vs 1.78 × 10-3 mm2 /s; P = 0.04). No significant difference in ADC values was observed between the two groups in any other cerebral territory. A cut-off value of 1.70 × 10-3 mm2 /s was associated with a sensitivity of 57% (95% CI, 18-90%), a specificity of 78% (95% CI, 63-88%), a positive predictive value of 27% (95% CI, 8-55%) and a negative predictive value of 93% (95% CI, 80-98%) for the prediction of adverse perinatal outcome. A mean frontal ADC value

1. Backyard bird feeding is one of the most common ways people engage with wildlife in many parts of the world. Given its scale, it can have profound consequences for the ecology of feeder birds and their behaviour. While previous work has primarily explored socio‐demographic factors associated with bird feeding, how observations of nature at backyard feeders (e.g. changes in feeder bird abundance, interaction with natural enemies and weather) influence people's propensity to feed birds remain largely unknown. 2. We examined the association between peoples’ observations at their backyard feeders and their emotions and behaviours related to providing food to birds. We conducted an online survey of a subset of United States participants in Project FeederWatch, a large‐scale citizen science project. 3. Overwhelmingly, respondents (n = 1,176) reported taking actions, such as managing predators or maintaining feeders, in response to observable natural factors (e.g. increased incidence of disease, the presence of predators, increased bird abundance). Additionally, respondents described a variety of emotional responses to the scenarios of depredation or disease at their feeders, some of which (particularly anger) had a small association with whether a respondent would take action in response. Respondents generally believed that their bird feeding benefits backyard birds (e.g. by improving overwinter survival and overall health), and indicated that natural factors (e.g. bird abundance, disease prevalence) and abiotic factors (i.e. cold temperature) had more of an influence on how much they feed birds than internal constraints such as time and money. 4. These findings suggest that human behaviour with respect to bird feeding is coupled to observations of nature, which could lead to feedbacks between provisioning intensity and ecological dynamics. Overall, our results have important implications for bird conservation and for understanding the potential benefits that humans receive from provisioning birds.

Locomotor stability is challenged by internal perturbations, e.g., motor noise, and external perturbations, e.g., changes in surface compliance. One means to compensate for such perturbations is to employ motor synergies, defined here as co-variation among a set of elements that acts to stabilize, or provide similar trial-to-trial (or step-to-step) output, even in the presence of small variations in initial conditions. Whereas evidence exists that synergies related to the upper extremities can be trained, the extent to which lower limb synergies, such as those which may be needed to successfully locomote in complex environments, remains unknown. The purpose of this study was to evaluate if resistance training (RT) in unstable environments could promote coordination patterns associated with stronger synergies during gait. Sixty-eight participants between the age of 65 and 80 were randomly assigned to one of three different RT modalities: stable whole-limb machine-based RT (S-MRT), instability free-weight RT (I-FRT), and stable machine-based adductor/abductor RT (S-MRTHIP). Before and after RT, participants walked across an even lab floor and a more challenging uneven surface with and without holding a weighted bag. The uncontrolled manifold control analysis (UCM) was used to calculate the synergy index (i.e., strength of the kinematic synergy) related to stabilization of our performance variable, the mediolateral trajectory of the swing foot, under each condition. Regardless of RT group, there was no effect of RT on the synergy index when walking across the even lab floor. However, the synergy index during the two uneven surface conditions was stronger after I-FRT but was not affected by the other RT modalities. The stronger synergy index for the I-FRT group was due to improved coordination as quantified by an overall increase in variability in elemental variable space but a decrease in the variability that negatively affects performance. The unstable environment offered by I-FRT allows for exploration of motor solutions in a manner that appears to transfer to challenging locomotor tasks. Introducing tasks that promote, rather than limit, exploration of motor solutions seems to be a valuable exercise modality to strengthen kinematic synergies that cannot be achieved with traditional strengthening paradigms (e.g., S-MRT).Clinical Trial Registration:www.ClinicalTrials.gov, identifier NCT03017365.

The reasons for higher fall risk of people with osteoarthritis (OA) compared to people without OA are not known. It is possible that following a loss of balance OA may negatively affect the recovery stepping response. Stepping responses have not been reported for people with knee OA. Here, we compared recovery step kinematics following laboratory-induced trip and following a large treadmill-delivered perturbation simulating a trip between a group of women with and without self-reported knee OA. We hypothesized that knee OA would significantly impair recovery step kinematics compared to those of a control group. Following the laboratory-induced trip, step length and trunk flexion velocity at recovery step completion of women with OA were significantly impaired and more so for the women who fell. Following the treadmill-delivered perturbation, the recovery step kinematics of women with OA were not significantly impaired. For both perturbations, the women who fell had significantly impaired recovery step kinematics compared to those who did not fall, regardless of OA. The results are consistent with previous work on healthy middle aged and older women and suggest that the same biomechanical risk factors for trip-related falls are shared by middle age and older women regardless of the presence of knee OA. The results support the need to determine whether training protocols which have been shown to improve recovery step kinematics and reduce prospective falls by healthy older women can have similar outcomes for people with knee OA.

Among dog breeds, the Dachshund has the highest lifetime incidence of intervertebral disc disease (IVDD). Intervertebral disc (IVD) calcification is an indicator of severe degeneration that predisposes to disc herniation. IVDD is heritable in Dachshunds, and in some countries, breeding candidates are screened to reduce IVDD occurrence by selecting dogs according to their score of radiographically detectable intervertebral disc calcification (RDIDC) and excluding dogs with ≥5 RDIDCs from breeding. This study evaluated the precision of scoring spinal radiographs for IVD calcification and subsequent classification of Dachshund dogs for breeding based on their RDIDC score. Digital radiographs of the spine were obtained in 19 clinically healthy, young adult Dachshunds, and scored for RDIDC independently by five scorers with varying levels of experience, three times each. Within scorer (repeatability) and between scorer (reproducibility) variability was estimated both at the individual IVD level and at the whole dog level for breeding classification purposes. At the IVD level, some degree of scorer effect was supported by the pairwise repeatability (92.3%; 95% CI: 88.8-94.7%) being marginally higher than the reproducibility (89.2%; 95% CI: 85.7-91.8%). Scorer-specific patterns confirmed the presence of scorer subjectivity. Repeatability significantly increased with scorer experience but the reproducibility did not. RDIDC scoring repeatability and reproducibility substantially decreased at the cervicothoracic spine region, likely due to anatomical superimpositions. At the dog level, a breeding classification could be repeated by the same scorer for 83.6% (95% CI: 73.8-90.2%) of the dogs, and was reproduced between two scorers for 80.2% (95% CI: 66.6-89.1%) of the dogs. The repeatability of breeding classification also seemed to increase with scorer experience but not the reproducibility. Overall, RDIDC scoring revealed some degree of inconsistency explained by scorer subjectivity and inexperience, and anatomical superimpositions. Scorer training and experience is strongly recommended to improve test precision and ensure appropriate classification of Dachshunds for breeding.

This phase 1 dose-escalation study evaluated pomalidomide, bortezomib (subcutaneous (SC) or intravenous (IV)) and low-dose dexamethasone (LoDEX) in lenalidomide-refractory and proteasome inhibitor-exposed relapsed or relapsed and refractory multiple myeloma (RRMM). In 21-day cycles, patients received pomalidomide (1–4 mg days 1–14), bortezomib (1–1.3 mg/m2 days 1, 4, 8 and 11 for cycles 1–8; days 1 and 8 for cycle ⩾9) and LoDEX. Primary endpoint was to determine the maximum tolerated dose (MTD). Thirty-four patients enrolled: 12 during escalation, 10 in the MTD IV bortezomib cohort and 12 in the MTD SC bortezomib cohort. Patients received a median of 2 prior lines of therapy; 97% bortezomib exposed. With no dose-limiting toxicities, MTD was defined as the maximum planned dose: pomalidomide 4 mg, bortezomib 1.3 mg/m2 and LoDEX. All patients discontinued treatment by data cutoff (2 April 2015). The most common grade 3/4 treatment-emergent adverse events were neutropenia (44%) and thrombocytopenia (26%), which occurred more frequently with IV than SC bortezomib. No grade 3/4 peripheral neuropathy or deep vein thrombosis was reported. Overall response rate was 65%. Median duration of response was 7.4 months. Pomalidomide, bortezomib and LoDEX was well tolerated and effective in lenalidomide-refractory and bortezomib-exposed patients with RRMM.

The uncontrolled manifold (UCM) analysis quantifies the extent to which co-variation among a set of variables facilitates consistent performance by partitioning variance in those variables into two components then calculating their normalized difference (i.e., the synergy index). Although UCM-derived measures are thought to depend on the number of data points analyzed, the minimum number needed to reasonably approximate true values of these measures is unknown. For each of two performance variables related to mechanical stability of gait, we evaluated changes in UCM-derived measures when increasing the number of analyzed points, here steps. Fourteen older adults walked on a treadmill while motion capture tracked movement. For each subject, n steps (where n = 2–99) were randomly sampled from the first 100, then used to calculate UCM-derived variables. For each subject, variables were expressed as a percent of the subject-specific value with n = 100 and averaged across 50 simulations. For each n, 95% confidence intervals (CIs) were calculated from group data. The minimum number of steps to “reasonably approximate” a variables was defined as the value of n for which the lower CI was >90% of the value with n = 100. Regardless of performance variable, reasonable approximations of the synergy index were attained with n = 16 steps, whereas n = 50 steps were needed for each of the variance components However, the differences between using 16 steps and 50 steps were small. Collecting 15–20 steps is recommended for a reasonable approximation of the synergy indices considered herein, particularly when data collection is constrained to a limited number of steps.