[Influence of Ankle Braces on the Prevalence of Ankle Inversion Injuries in the Swiss Volleyball National League A]. / Einfluss von Sprunggelenksorthesen auf die Prävalenz von Supinationstraumen im Volleyball in der Schweizer Nationalliga A.

BACKGROUND: Ankle inversion is a common injury among volleyball players. The injury rate during a game is 2.1 times higher than during training. As a result, the preventive use of ankle braces is frequently observed in Swiss volleyball leagues. Studies have shown that ankle braces have a preventive effect on the prevalence of ankle inversion. In Switzerland there has been no investigation into the preventive use of braces and their influence on prevalence. For this reason, the goals of this study are 1) to determine when, why and by whom ankle braces are worn and 2) to evaluate the injury rate of users and non-users of ankle braces. SUBJECTS AND METHODS: A modified questionnaire was sent to 18 men's and women's teams of the Swiss National League A. The questionnaire included questions about injury rates and the circumstances of ankle inversion injuries. The data were statistically analysed with Microsoft Excel 2012 and SPSS Version 20. RESULTS: The overall response rate was 61 %, allowing data from 181 players to be analysed. 33 % (59 of 181) of the players used an ankle brace. There was a statistically significant difference in the prevalence of ankle inversion between users (12 injured) and non-users (8 injured) (p = 0.006). Wearing an ankle brace during training or during a game made no difference in the prevention of injuries (p = 0.356). More athletes were injured during training (n = 13) than during a game (n = 7). CONCLUSION: The results of the present study indicate that volleyball players preferably wear ankle braces to prevent injury. More than one third of the players in the study wore an ankle brace, 60 % for primary prevention and 40 % for secondary prevention due to a previous injury. The study shows that significantly more users than non-users of ankle braces were injured. This is contrary to literature. Furthermore it was shown that more injuries occur during training than during a game. This finding results from the fact that ankle braces were rarely worn during training. It is concluded that ankle braces must be worn consistently, especially during training.

[Injuries in the Martial Arts Judo, Taekwondo and Wrestling - A Systematic Review]. / Verletzungen in den Kampfsportarten Judo, Taekwondo und Ringen - Eine systematische Übersichtsarbeit.

BACKGROUND: Martial arts such as judo, taekwondo and wrestling are regulated, usually athletic duels. The aim is to score better than your opponent or to win. As with any type of sport, athletes in martial arts sustain minor and major injuries, which may have many negative consequences. In addition, sports injuries and their rehabilitation generate high costs to the healthcare system. In contrast to the FIFA 11+ warm-up program, no preventive programs have been postulated for injury prevention in these martial arts. Therefore, the aim of this systematic review was to summarise the latest research findings and to evaluate whether initial recommendations can be given for the reduction of injuries in the martial arts judo, wrestling and taekwondo. METHODS: To gain an overview of the latest research findings, we searched for systematic reviews in PEDro, PubMed, Cochrane and the internet search engine Google Scholar. The methodological quality of these reviews was assessed using the Critical Appraisal Tool for a Systematic Review (CASP), and data was extracted on the risk of injury, injury location and injury type. RESULTS: It was found that all three review articles are of low to moderate methodological quality. Regarding injury location, it became evident that the extremities are particularly vulnerable to injury in all three martial arts. Effusion was observed to be the most common type of injury. CONCLUSION: Due to the moderate methodological quality and the injury type of effusion, it is not possible to formulate recommendations for injury prevention. Moreover, uniform definitions should be developed to describe sports injuries.

Spatiotemporal gait parameters during dual task walking in need of care elderly and young adults. A cross-sectional study.

BACKGROUND: Up to now there have only been marginal data in the elderly in need of care regarding spatiotemporal gait parameters during single (ST) and dual tasking (DT). AIM: The aim of this study was to allocate data for gait speed, cadence and stride length cycle variability in the elderly in need of care and in young adults during ST and DT, to compare the two groups and to demonstrate the impact of ST and DT on gait parameters. MATERIAL AND METHODS: This cross-sectional study investigated a group of 16 young healthy adults (mean age 23.0 ± 2.5 years) and a group of 16 elderly persons in need of care (mean age 85.5 ± 0.6 years). The RehaWatch system was used to collect the spatiotemporal gait parameters cadence, speed and stride length. The participants completed four different measurements during normal walking and fast walking during ST and DT over a walking distance of 20 m. The Wilcoxon rank sum test and Whitney-U test were used for statistical analysis. RESULTS: Gait speed (ST and DT: p < 0.001), cadence (ST and DT: p < 0.001) and gait variability (ST: p = 0.007, DT: p = 0.003) were significantly reduced in the elderly in need of care group compared to the young group. The gait speed in the elderly in need of care group decreased from normal to fast walking (ST = - 2.8%, DT = - 12.2%) compared to the young group (ST = 31.5%, DT = 25.2%). CONCLUSION: The results of this study are comparable with the results of existing studies, which investigated falling and non-falling participants. Elderly people in need of care cannot increase the normal gait speed.

[Feasibility of balance training on mats in healthy, moderately sportive women in old age. A pilot study]. / Machbarkeit eines Gleichgewichtstrainings auf Matten bei gesunden, moderat sportlichen Frauen im Alter. Eine Pilotstudie.

PURPOSE: The aim of this pilot study was to assess the feasibility and the effect size of weekly group exercise sessions on an Airex® pad with an additional home program on the participants' balance. MATERIALS AND METHODS: Two training sessions (once a week in-group and once a week as a home program) were administered for 4 weeks. The intervention group (IG) trained on Airex® pads and the control group (CG) without the pad. This study examined the feasibility in terms of recruitment and randomization process, and compliance. Moreover, the effects were evaluated for static, dynamic, and functional balance. RESULTS: A total of 11 healthy women were recruited, and 10 women completed the 4-week training program (one drop-out was recorded). Of a total of 88 training sessions, 82 were completed. The IG showed a significant difference for one test of dynamic balance. CONCLUSION: This pilot study was feasible. However, changes regarding recruitment and compliance should be made for future studies. Sensitive measuring instruments must be used for the evaluation of balance changes.

[Does muscle activation during whole-body vibration induce bone density improvement in postmenopausal women?--A systematic review]. / Hat die Aktivierung der Muskulatur durch Ganzkörpervibration einen Effekt auf die Knochendichte von postmenopausalen Frauen? Eine systematische Literaturübersicht.

BACKGROUND: Whole body vibration training (WBV) stimulates muscles by mechanical vibrations. The resulting muscle activity and bone deformation may provoke an increase in bone density. The aim of this systematic review was to evaluate whether muscle activation and muscle strengthening caused by vibration training has an effect on bone density in postmenopausal women. METHODS: This systematic review was conducted according to the guidelines of the PRISMA statement for meta-analyses and systematic reviews. The literature search was conducted in several electronic databases (PubMed und CINAHL) and Google Scholar. The literature search was conducted between June 2012 and August 2013. The methodological quality of the included studies was assessed using the Cochrane risk of bias tool by two independent persons. RESULTS: A total of 246 studies was found. In this present analysis three studies with vertical and two studies with side-alternating WBV were included, totalling 368 participants with an age range between 60.7 and 79.6 years. From those 132 participants trained on vertically while 67 participants trained on side-alternating WBV engines. The included study shows a moderate to high risk of bias. The selected frequencies ranged from 12.0 Hz to 40.0 Hz for vertical WBV and 12.5 Hz for side-alternating WBV. The amplitude ranged between 1.7 and 12.0 mm with an acceleration from 0.1 to 10.0 g. CONCLUSION: This systematic review showed significant influences on the isometric maximal voluntary contraction (IMVC) between 15.1 and 16.5 % and on dynamic maximal strength (DMS) between 7.9 to 16.5 % after vertically WBV (frequencies: 30.0 to 40.0 Hz; 3 sessions per week; 15 minutes per session) and on IMV with 26.6 % (frequency: 12.5 Hz; 3 sessions per week; 15 minutes per session). This increased muscle activity resulted in an improved bone density in the lumbar spine between 0.5 % to 0.7 % and the hip between 0.8 % to 0.9 % in postmenopausal women. These clinically significant findings should be confirmed by a large high-quality randomised controlled trial and reported following the CONSORT Statement guidelines.

[The relevance of core muscles in ice hockey players: a feasibility study]. / Die Bedeutung der Rumpfmuskulatur bei Eishockeyspielern: eine Machbarkeitsstudie.

BACKGROUND: Good core strength is seen as a condition for high performance in sports. In general, especially maximum voluntary contraction (MVC) and strength endurance (SE) measurements of the core muscles are used. In addition, a few studies can be found that examine the core muscles in terms of MVC, rate of force development (RFD) and SE. Primary aims of this feasibility study were to investigate the feasibility regarding recruiting process, compliance and safety of the testing conditions and raise the force capabilities MVC, RFD and SE of the core muscles in amateur ice hockey players. Secondarily, tendencies of correlations between muscle activity and either shot speed and sprint time shall be examined. SUBJECTS/METHODS: In this feasibility study the recruitment process has been approved by 29 ice hockey players, their adherence to the study measurements of trunk muscles, and safety of the measurements was evaluated. To determine the MVC, RFD and SE for the ventral, lateral and dorsal core muscles a dynamic force measurement was performed. To determine the correlation between core muscles and shot speed and 40-m sprint, respectively, the rank correlation coefficient (rho) from Spearman was used. RESULTS: The recruited number of eight field players and one goal-keeper was not very high. The compliance with 100 % was excellent. The players reported no adverse symptoms or injuries after the measurements. The results show median values for the ventral core muscles for MVC with 46.5 kg for RFD with 2.23 m/s2 and 96 s for the SE. For lateral core muscle median values of the lateral core muscles for MVC with 71.10 kg, RFD with 2.59 m/s2 and for SE over 66 s were determined. The dorsal core muscles shows values for MVC 69.7 kg, for RFD 3.39 m/s2 and for SE of 75 s. High correlations between MVC of the ventral core muscles (rho = -0.721, p = 0.021), and between the SE of the ventral core muscles (rho = 0.787, p = 0.012), and the shot velocity rate were determined. Another high correlation between SE of the ventral core muscles and sprint over 40 m (rho = 0.717, p = 0.030) could be demonstrated. CONCLUSION: This feasibility study has shown that the implementation of the selected design is adapted for future studies. Further studies are needed to better understand the relationship between the velocity rate and the MVC, and the SE respectively, as well as between the sprint and the SE.

[Effect of continuous passive motion for cartilage regenerative surgery - a systematic literature review]. / Wirkung von passiven Motorbewegungsschienen nach knorpelregenerativen Eingriffen - eine systematische Literaturübersicht.

BACKGROUND: The aim of this systematic review was to evaluate treatment effects of continuous passive motion (CPM) after surgical cartilage repair. PATIENTS/MATERIAL AND METHODS: A literature search was conducted in the Cochrane Central Register of Controlled Trials, EMBASE, International Clinical Trials Registry Platform, MEDLINE, Trip Database and in bibliographies of included studies. Two independent researchers evaluated the quality of original investigations by the Cochrane Risk of Bias tool. Systematic reviews were checked by the CBO/Dutch Cochrane Centre Guideline. RESULTS: A total of 1541 studies was initially retrieved from the databases. After screening for inclusion criteria, one review and ten original papers could be included for further evaluation. Studies showed methodological weaknesses. Heterogeneity of outcome measures and the fact that 6 of 9 studies with an one-group pre-post design measured the combined effect of surgical treatment and CPM prevented a meta-analysis. CONCLUSION: Three studies described significant improvements with regard to subjective outcome such as pain, swelling, Quality Life Survey, Knee Society score, WOMAC score or rating Cincinnati due to the surgical treatment and the CPM intervention of cartilage defects in the knee. Six (case) studies suggested an enhanced cartilage quality of the patients after CPM. More high-quality randomised controlled trials are needed to provide high level evidence.

[Acute effects of fast dynamic stretching on rate of force development in ice hockey players: a pilot study]. / Akute Effekte des schnellen dynamischen Dehnens auf die Schnellkraft von Eishockeyspielern: eine Pilotstudie.

BACKGROUND: Fast dynamic stretching has a positive effect on rate of force development in ice hockey players. The aim of this pilot study was to evaluate the influence of fast dynamic stretching (FDS) of the gluteus maximus muscle on rate of force development. SUBJECTS/METHODS: This study included 12 healthy ice hockey players. The intervention was based on a fast dynamic stretching of the gluteus maximus muscle. For quantification, measurements were performed before and after the intervention. The rate of force development was determined by using the drop jump (DJ) for ground contact time and jump height, and sprint time was measured on ice over 20 meters. RESULTS: The intervention showed significant extension of the ground reaction time. The jump height and the sprint time showed no significant differences after FDS intervention. CONCLUSION: The data in this present randomised controlled pilot study showed that FDS interventions on the gluteus maximus muscle have no influence on rate of force development. For future studies, it is recommended that the study protocol should be modified with regard to determining the stretched muscle groups. Furthermore, the FDS intervention on the gluteus maximus muscle showed no positive influence on DJ and sprint.

Hormonal and synaptic influences of serotonin on adult neurogenesis.

New neurons are incorporated into the adult brains of a variety of organisms, from humans and higher vertebrates, to non-vertebrates such as crustaceans. In virtually all of these systems serotonergic pathways appear to provide important regulatory influences over the machinery producing the new neurons. We have developed an in vitro preparation where adult neurogenesis can be maintained under highly controlled conditions, and are using this to test the influence of hormones on the production of neurons in the crustacean (Homarus americanus) brain. Serotonin levels have been manipulated in this in vitro preparation, and the resulting effects on the rate of neurogenesis have been documented. In addition we have compared in vitro influences of serotonin with results acquired from in vivo exposure of whole animals to serotonin. These experiments suggest that there are multiple mechanisms and pathways by which serotonin may regulate neurogenesis in the crustacean brain: (1) serotonin is effective in regulating neurogenesis at levels as low as 10(-10)M, suggesting that circulating serotonin may have hormonal influences on neuronal precursor cells residing in a vascular niche or the proliferation zones; (2) contrasting effects of serotonin on neurogenesis (up- vs. down-regulation) at high concentrations (10(-4)M), dependent upon whether eyestalk tissue is present or absent, indicate that serotonin elicits the release of substances from the sinus glands that are capable of suppressing neurogenesis; (3) previously demonstrated (Beltz, B.S., Benton, J.L., Sullivan, J.M., 2001. Transient uptake of serotonin by newborn olfactory projection neurons. Proc. Natl. Acad. Sci. USA 98, 12730-12735) serotonergic fibers from the dorsal giant neuron project directly into the proliferation zone in Cluster 10, suggest synaptic or local influences on neurogenesis in the proliferation zones where the final cell divisions and neuronal differentiation occur. Serotonin therefore regulates neurogenesis by multiple pathways, and the specific mode of influence is concentration-dependent.

[Combination of prehospital systemic thrombolytic therapy with endovascular procedures in the treatment of patients with acute myocardial infarction].

Since July 2002 we have been conducting a study of efficacy of prehospital thrombolytic therapy combined with subsequent endovascular procedures in the treatment of patients with acute myocardial infarction. Fifty nine patients received prehospital fibrinolysis with tissue-type plasminogen activator (TPA, n=28) or streptokinase (n=31) within 6 hours after onset of symptoms. TPA infusion compared with that of streptokinase was associated with smaller ischemic myocardial damage and lower frequency of side effects (3.6 and 38.7%, respectively). Angioplasty or stenting of infarct related arteries were carried out in 47 of these patients. The group of patients subjected to endovascular interventions was characterized by a low rate of in-hospital cardiac events and zero mortality.

[Stent thrombosis in patients with myocardial infarction]. / Tromboz stenta u patsientov s ostrym infarktom miokarda.

The problem of stent thrombosis in patients with myocardial infarction is reviewed with consideration of possible mechanisms and causes of in-stent thrombus formation during first 30 days after the procedure. Roles of the patient factor, factor of the stented vessel, stent in self, stent deployment technique, and management after stenting are discussed.

The vaccinia virus E3L protein interacts with SUMO-1 and ribosomal protein L23a in a yeast two hybrid assay.

We report the results of a two-hybrid study which identified clones from a HeLa cDNA library that interact with the vaccinia virus protein E3L. These clones encode the nuclear protein SUMO-1 (also known as PIC-1, sentrin or GMP-1); the cytoplasmic ribosomal protein L23a; and a small peptide sequence of unknown significance.

Mirroring doubly excited resonances in argon.

New features are revealed in the low-energy photoionization spectrum of Ar by critically combining high photon resolution and differential photoelectron spectroscopic techniques. Two LS-forbidden doubly excited resonances are seen in the 3p(-1)(3/2, 1/2) partial cross sections which exhibit mirroring profiles, resulting in complete cancellation in the total photoionization cross section, as was predicted by Liu and Starace [Phys. Rev. A 59, R1731 (1999)]. These results demonstrate that a new class of weakly spin-orbit induced, mirroring resonances should be observable in partial, but not in total, collisional cross sections involving atoms, molecules, and solids in general.

Hip hiking and circumduction: quantitative definitions.

OBJECTIVE: To define and propose clinically useful quantitative measurements of hip hiking and circumduction using standard three-dimensional motion analysis techniques. DESIGN: We studied pelvic, hip, and thigh motions in 23 subjects with hemiparetic, stiff-legged gait as a result of stroke and compared these motions with those obtained from 23 able-bodied controls. RESULTS: We observed significantly increased hip abduction on the unaffected limb during stance, with simultaneous elevation of the affected side of the pelvis during swing. We define these differences as hip hiking and, thus, can quantify the degree to which hip hiking occurs by measuring the unaffected coronal hip angle and/or the coronal pelvic angle when the affected limb is in midswing. We also observed a greater than normal coronal thigh angle during midswing of the affected limb that we can use to quantitatively define circumduction. Of note, hip abduction during swing was not increased on the affected swing limb, compared with the control. CONCLUSIONS: Hip hiking can be defined precisely as unaffected coronal hip and/or pelvic angle when the affected limb is in midswing and circumduction can be defined as greater than normal coronal thigh angle during midswing of the affected limb. These precise definitions should allow us to better communicate and understand the implications of these gait patterns, and can serve as the basis for clinically meaningful quantitative assessment and outcome measurement tools.

Personal exercise habits and counseling practices of primary care physicians: a national survey.

OBJECTIVE: Regular physical activity can reduce the incidence and prevalence of many chronic diseases. A vast majority of Americans cite their physician as their primary source of information regarding healthy lifestyle decisions. This study was designed to obtain information about the personal exercise behavior and counseling practices of primary care physicians, to evaluate the relationship between their personal and professional exercise practices, and to determine whether physician specialty is associated with these practices. DESIGN: A cross-sectional survey was mailed to a randomly selected sample of primary care physicians in the United States. A questionnaire was used to obtain detailed information on the personal exercise habits, counseling practices, and barriers to counseling of these physicians, regarding both aerobic exercise and strength training. PARTICIPANTS: 298 primary care physicians, comprising 84 family practitioners, 79 pediatricians, 58 geriatricians, and 77 internists. MAIN OUTCOME MEASURES: Frequency of physician exercise, exercise counseling, and relationship between these practices. RESULTS: Physicians who perform aerobic exercise regularly are more likely to counsel their patients on the benefits of these exercises, as are physicians who perform strength training. Pediatricians and geriatricians counsel fewer patients about aerobic exercise than family practitioners and internists. Counseling regarding strength training is less common in all physician groups surveyed, and lowest among pediatricians, of whom 50% did not advise these exercises for any of their patients. Inadequate time was noted by 61% and inadequate knowledge and/or experience by 16% of respondents as the major barriers to counseling regarding aerobic exercise. CONCLUSION: Physicians who exercise are more likely to counsel their patients to exercise. Inadequate time and knowledge/experience regarding exercise are the most common barriers to counseling identified. These findings suggest strategies that might increase physician exercise counseling behavior.

Compensatory advantages of toe walking.

OBJECTIVES: The study's hypothesis is that toe walking requires less peak muscle strength distally about the ankle and knee compared with normal heel-toe walking and thus may have compensatory advantages for patients with upper motor neuron injury and distal muscle weakness. DESIGN: Motion analysis and force platform data were collected in able-bodied subjects during toe walking and normal walking. Sagittal plane joint torques reflecting muscle force requirements and joint powers reflecting nonisometric muscle contraction were compared between the two conditions using paired t tests, applying a Bonferroni correction for multiple comparisons. SETTING: A gait laboratory. SUBJECTS: Seventeen able-bodied adults, 9 of whom were ballet dancers. MAIN OUTCOME MEASURES: Peak hip, knee, and ankle joint torque and power variables during walking. RESULTS: Peak ankle plantarflexor torque and ankle power generation during terminal stance and preswing were reduced (p<.001), as compared with normal heel-toe walking. The normal ankle dorsiflexor torque at initial contact-and the knee extensor torque and knee power generation during loading response were all essentially absent during toe walking. Hip extensor torque and hip power generation during the loading response phase were greater for toe walking (p<.001). CONCLUSION: Toe walking may require less ankle plantarflexor, ankle dorsiflexor, and knee extensor strength than normal heel-toe walking and thus may have compensatory advantages for patients with upper motor neuron injury and distal lower extremity weakness.

Pesticide exposure and creatinine variation among young children.

Pesticide exposure may differentially impact young children; they live closer to the ground and take in greater amounts of food relative to body mass than older children or adults. We are using an organophosphate (OP) urinary biomarker screen (gas chromatography with flame photometric detection, GC/FPD) to evaluate pesticide exposure among 154 children < or = 6 years of age living in a heavily farmed border (US-Mexico) community. The screen detects diethylphosphates (DEPs) and dimethylphosphates (DMPs) above a reference range of 1000 non-occupationally exposed individuals (DL=25 microg/g creatinine, Cr). At least one metabolite was detected for 33% of the subjects; many samples contained multiple biomarkers. DEP was detected in 5% of the subjects. DMP and DMTP were frequently measured (25% and 26%, respectively). Biomarker concentrations are adjusted by the body's metabolism of Cr as an indicator of urine dilution. Cr concentrations were examined separately to evaluate their effect on internal dose measures. Cr concentrations were significantly different by season (K-W=0.83, P=0.022). Significant differences exist between the autumn:spring (P=0.038) Cr concentrations and between summer:autumn (P=0.041) Cr concentrations based on Mann-Whitney U=1070.5, z=-2.041, (P=0.041). Our analysis of NHANES III data did not reflect seasonal Cr differences for 6 year olds. No younger children were included. Absorbed daily dose (ADD) estimates were calculated for children with the highest concentrations of metabolite. Calculations are theoretical values assuming that the entirety of a given metabolite was metabolized from a single pesticide. Several class appropriate pesticides were evaluated. For the children with the highest levels, almost all estimated ADDs exceeded the RfD. Although the actual metabolite concentrations dropped appreciably, ADD were still exceeded RfDs at the 95th percentile. The urinary OP screen was effective in identifying subjects with atypical internal doses. Daily Cr yield is a critical component in ADD calculations. Cr variability produces differences in internal dose measurement and estimates of ADD independent of exposure. Cr variability among young children needs to be examined, and caution should be applied when evaluating Cr adjusted internal doses for children.

Spatial distributions of arsenic exposure and mining communities from NHEXAS Arizona. National Human Exposure Assessment Survey.

Within the context of the National Human Exposure Assessment Survey (NHEXAS), metals were evaluated in the air, soil, dust, water, food, beverages, and urine of a single respondent. Potential doses were calculated for five metals including arsenic. In this paper, we seek to validate the potential dose calculations through spatial analysis of the data. Others report elevated arsenic concentrations in biological and environmental samples from residents of mining towns, particularly Ajo, Arizona. These reports led us to expect potential arsenic doses above the 90th percentile of the NHEXAS exposure distribution to be from residents of mining communities. Arsenic dose was calculated using media concentrations, time activity patterns, and published exposure factors. Of the 179 homes evaluated, 54 were in mining communities; 11 of these were considered separately for reasons of population bias. Of the 17 homes with the greatest potential arsenic doses, almost half (47%) were in mining communities. We evaluated the potential doses by media from nonmining and mining areas using the nonparametric Mann-Whitney U test. Statistically significant (p = 0.05) differences were found between mining (n = 43) and nonmining sites (n = 122) for total exposure and for each of the following media: house dust, yard soil, outdoor air, beverage consumed, and water consumed. No differences were found in either food or indoor air of mining and nonmining areas. We eliminated outliers and repeated the test for all media; significance increased. Dietary, organic arsenic from fish consumption contributed to elevated arsenic exposure among people from nonmining communities and acted as an initial confounder. When controlling for fish consumption, we were able to validate our potential dose model using arsenic, particularly in Ajo. Further, we identified three mining communities lacking elevated arsenic exposure. Additional work is needed speciating the arsenic and evaluating health risks. The utilization of Geographic Information System facilitated spatial this project and paves the way for more sophisticated future spatial analyses.

Evaluations of primary metals from NHEXAS Arizona: distributions and preliminary exposures. National Human Exposure Assessment Survey.

NHEXAS AZ is a multimedia, multipathway exposure assessment survey designed to evaluate metals and other analytes. This paper reports the analyte-specific concentration distributions in each of the media examined (air, soil, house dust, food, beverage, and water), for various methodologies used (inductively coupled plasma-atomic emission spectroscopy and hydride generation-atomic absorption spectroscopy). Results are reported for the five primary metals (Pb, As, Cd, Cr, and Ni). Ingestion was the most important pathway of exposure. Metal concentrations in air were very low (ng/m3) and found only above the 90th percentile. Metals were commonly found in house dust and soil. Exposure transfer coefficients minimize the importance of this component for those over the age of 6 years. When ranked by exposure, food, beverage, and water appeared to be the primary contributors of metal exposure in NHEXAS AZ. For instance, at the 90th percentile, Pb was undetected in air, found at 131 and 118 microg/m3 in floor dust and soil, respectively, and measured at 16 microg/kg in food, 7.1 microg/kg in beverage, and 2.0 and 1.3 microg/l in drinking and tap water, respectively. We calculated preliminary estimates of total exposure (microg/day) for each participant and examined them independently by age, gender, and ethnicity as reported by the subjects in the NHEXAS questionnaire. At the 90th percentile for Pb, total exposures were 64 microg/day across all subjects (n=176); adult men (n=55) had the greatest exposure (73 microg/day) and children (n=35) the least (37 microg/day). Hispanics (n=54) had greater exposure to Pb (68 microg/day) than non-Hispanics (n=119; 50 microg/day), whereas non-Hispanics had greater exposure for all other metals reported. These results have implications related to environmental justice. The NHEXAS project provides information to make informed decisions for protecting and promoting appropriate public health policy.

Spastic paretic stiff-legged gait: biomechanics of the unaffected limb.

A concern for individuals with hemiparesis affecting their gait, which heretofore has never been studied, is the possibility that various compensations occurring in the unaffected limb may strain or fatigue the muscles or ligaments and/or predispose to joint injury in that limb. We studied the biomechanics of the unaffected limb during walking in 20 subjects with hemiparesis who had stiff-legged gait as a result of stroke. An optoelectronic motion analysis and force platform system was used to estimate torques in all three planes about the hip, knee, and ankle. Sagittal plane joint motion and power about the unaffected hip, knee, and ankle were also studied. Data were compared with control walking data collected from 20 able-bodied controls. On average, peak torques and powers were all either reduced or the same compared with controls, even though in some instances values were >2 standard deviations (SD) above the control means. Our findings suggest that on average the probability of excessive muscular-tendon effort and the risk for biomechanical injury in the unaffected limb are minimal compared with able-bodied, walking controls. However, given individual variability, we recommend routine clinical gait analysis for all people with stiff-legged gait to eliminate excessive values in certain biomechanical parameters, which could, if not addressed, predispose to muscle-tendon strain or joint or ligamentous injury.