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Jackleg drill operators are exposed to harmful levels of hand-arm vibration (HAV). Anti-vibration handles and gloves provide modest reductions in HAV exposures and forearm muscle exertion from the use of AV handles and gloves by jackleg drill operators. The goal of this pilot study was to investigate changes in HAV with the use of anti-vibration gloves and handles compared to forearm muscle exertion experienced by operators and measured with surface electromyography (EMG). Five subjects operated the drill under four different cases: no anti-vibration controls, anti-vibration gloves only, anti-vibration handle only, and simultaneous anti-vibration handle and glove use. Muscle exertion was expressed as a percent of maximum voluntary contraction (%MVC) and was compared using Welch’s ANOVA with Games-Howell post-hoc comparisons. The case with both anti-vibration controls in use simultaneously (largest grip diameter) was associated with a mean %MVC of 36.13% during operation for all forearm muscles combined, which was significantly higher than the other cases (p < 0.05). There were no statistically significant differences in mean HAV exposures. The anti-vibration handle with anti-vibration glove case only increased the maximum allowable exposure time by eight minutes as compared to the control case without any anti-vibration controls. These results suggest that the modest HAV exposure reductions from the use of anti-vibration handles and gloves may pale in comparison to the increased muscle exertion resulting from their use, and this tradeoff among jackleg drill operators is a potential concern that warrants further investigation.

Studies on hand-transmitted vibration exposure, biodynamic responses, and biological effects were conducted by researchers at the Health Effects Laboratory Division (HELD) of the National Institute for Occupational Safety and Health (NIOSH) during the last 20 years. These studies are systematically reviewed in this report, along with the identification of areas where additional research is needed. The majority of the studies cover the following aspects: (i) the methods and techniques for measuring hand-transmitted vibration exposure; (ii) vibration biodynamics of the hand–arm system and the quantification of vibration exposure; (iii) biological effects of hand-transmitted vibration exposure; (iv) measurements of vibration-induced health effects; (iv) quantification of influencing biomechanical effects; and (v) intervention methods and technologies for controlling hand-transmitted vibration exposure. The major findings of the studies are summarized and discussed.

Background Dupuytren’s contracture was recently designated a prescribed occupational disease when it occurs in patients with previous hand–arm vibration (HAV) exposure. Aims The aims of this study were to describe the impact of self-reported HAV exposure on upper limb function and satisfaction following surgery for Dupuytren’s contracture. Methods Paired pre- and postoperative Quick version of Disabilities of the Arm, Shoulder and Hand (QuickDASH) and patient satisfaction questionnaires were prospectively collected from all patients undergoing surgery for Dupuytren’s contracture over a 6-year period. Patients self-reported HAV exposure duration. Results Results were available for 425 hands (65%) at mean 13 months postoperatively. There were 111 patients (26%) that reported HAV exposure. The prevalence of HAV exposure was significantly greater in male compared with female patients (32% versus 4%; P < 0.001). A statistically significant difference in preoperative (difference 7.47; 95% confidence interval 4.78–10.17; P < 0.001) and postoperative QuickDASH score (difference 6.78; 95% confidence interval 2.69–10.88; P < 0.001) was observed between the two groups, but difference in QuickDASH improvement was not significantly different (difference 1.76; 95% confidence interval −1.58 to 5.10; P > 0.05). No significant difference in satisfaction rate or return to work was observed between the two groups. Conclusions Previous HAV exposure influenced the pre and postoperative function in patients undergoing surgery for Dupuytren’s contracture, but had no effect on satisfaction or return to work. Further prospective research will be required to determine whether the introduction of a compensatory framework will have a more profound effect on the functional outcomes of surgery.

ObjectiveTo estimate the prevalence of hand-arm vibration (HAV) in Australian workplaces.MethodsThe Australian Workplace Exposure Survey (AWES)—Hearing was a cross-sectional telephone survey of Australian workers conducted in 2016–2017. Respondents were asked about the time spent using tools or performing tasks known to be associated with HAV during their most recent working day. We created a library of HAV magnitude levels for each tool/task and estimated each worker’s daily HAV exposure level using standard formulae. We categorized each worker as to whether they exceeded the daily occupational limits of 2.5 and 5.0 m/s2. Results were extrapolated to the Australian working population using a raked weighting method.ResultsIn our sample of 4991 workers, 5.4% of men and 0.7% of women exceeded the HAV action limit of 2.5 m/s2 on their most recent working day. We estimate that 3.8% of the Australian workforce exceeds the HAV limit of 2.5 m/s2 and 0.8% exceeds the 5 m/s2 limit. Men were more likely to exceed the HAV limits than women, as were those with trade qualifications, and those who worked in remote locations. Workers in the construction, farming, and automobile industries had the highest prevalence of HAV exposure. Tool groups that contributed to higher exposure levels included: compactors, rollers, and tampers; power hammers and jackhammers; and underground mining equipment.ConclusionsHAV is common in the Australian working population. Given the health risks associated with this exposure, reduction strategies and interventions should be developed, with engineering controls as the starting point for exposure reduction strategies.

Context: Rising incidence of hand-arm vibration on dentists is an increasing concern in India. The purpose of this study is to investigate the dose-response relationship derived using ready reckoner and to identify the most practicable exposure action and limit value measure that can be collected to aid in the health assessment of dentists exposed to hand-arm vibration. Aims: The objective of this research is to determine the magnitude of vibration transmitted per day among dentists exposed to the vibrating hand-held tools; To determine the association of the magnitude of vibration transmission with duration of usage and to determine the proportion of Exposure Action Value (EAV) and Exposure Limit Value (ELV) among dentists. Methods and Materials: Using a cross-sectional analysis, this study analyzed the incidence of hand-arm vibration on 92 dentists and measured these results with a ready reckoner. Statistical analysis used: Chi-Square Test was used to test the association of vibration exposure with selected parameters that is of interest such as years of experience, duration of work, vibration magnitude of the instrument. Results: The proximity of middle-aged dentists with more than or equal to 10 years of working experience were found to play a huge role in exposure to hand-arm vibration. Conclusions: This study definitely answers the questions regarding the exposure to hand-arm vibration on dentists. This could be minimized reducing exposure times, health surveillance, improved handpieces and other equipment and improving the overall ergonomics of the workplace. Keywords: Dentistry, Exposure assessment, Handarm vibration, Health surveillance.

In industry 4,0, the establishment of an interconnected environment where human operators cooperate with the machines offers the opportunity for substantially improving the ergonomics and safety conditions of the workplace. This topic is discussed in the paper referring to the vibration risk, which is a well-known cause of work-related pathologies. A wearable device has been developed to collect vibration data and to segment the signals obtained in time windows. A machine learning classifier is then proposed to recognize the worker’s activity and to evaluate the exposure to vibration risks. The experimental results demonstrate the feasibility and effectiveness of the methodology proposed.

From power hand tools to hand-arm systems, there are many occupational diseases associated with vibration transmission. People who have worked for a long time with the formal exposure of vibration companies suffer from trembling white fingers (VWF). These hazards are mainly due to the extreme exposure of vibrations spread from the grinding machine to the hand-held system. International standards have been developed to assess the risk of injury after exposure to these types of vibrations. The current standards recognize that aspects such as the effect of vibration transmission direction, arm posture, hand grip or force need to be investigated. The mathematical model of five DOF hand arm system was studied and simulation was done by using SIMULINK software. Displacement verses Time graphs were plotted to find at what frequency maximum amplitude existed and it was seen at frequency 10 Hz

Exoskeleton devices are currently being utilized in a variety of occupational settings to reduce musculoskeletal efforts to lower fatigue, improve performance, and minimize work-related injuries associated with musculoskeletal disorders (MSDs). The intrinsic challenges that accompany the development of fully supporting and active upper extremity multi-degrees of freedom (DOF) devices include not only the mechanical design, but also lack of an intuitive way to control and operate these devices. A proof-of-concept instrumented handle consisting an embedded sensor network was developed with the intention to utilize artificial neural networks (ANN) to properly identify the intended motion of the user and to estimate the motion intensity. Results show this method is feasible and delivers useful insight into developing the next stages of the “smart handle” technology that will include the remaining hand motions, correctly classifying combination of intended motions and using the handle output to control complex multi-DOF upper extremity exoskeletons devices.

© 2020 Wiley Periodicals LLCJob rotation schedules are generally conducted without considering hand–arm vibration (HAV) exposure especially in manufacturing firms, such as heavy industry, which confront ergonomic risks easily. This does not create any occupational health and safety (OHS) issues in the short term; however, certain occupational diseases such as the white finger disease are inevitable in the long-term. This paper investigates how the risks of developing HAV-related occupational diseases can be minimized by producing optimal job rotation schedules using ergonomic mathematical models. In the proposed models, both ergonomic and traditional aspects of manufacturing environments are considered. Moreover, the skill level and workers' day off preferences are also considered for total system efficiency. The mixed-integer programming approach is used to formulate the models. The applicability of the models is tested using real-world data. It is seen that the total assignment cost of the models increases when the ergonomic aims are included in the models. Thus, there is a conflicting relationship between economic and ergonomic aims. The main findings of the models show that the employees' HAV exposure level can be kept under control with one simple constraint. By employing these models, employees and employers can be protected in terms of not only OHS but also economic issues.

Purpose This study describes the impact of self-reported hand–arm vibration (HAV) exposure on patient-reported outcomes, health-related quality of life, and satisfaction after carpal tunnel release. Methods We prospectively collected data from Quick–Disabilities of the Arm, Shoulder, and Hand (QuickDASH), patient satisfaction, and 5-level EuroQol-5D questionnaires before and after surgery. Patient-reported outcomes were available for 475 patients (78% follow-up at a mean of 14 months). Fifteen patients were excluded, giving a final cohort of 460 patients. Results A total of 119 patients reported HAV exposure (26%). Median postoperative QuickDASH and QuickDASH improvement were significantly worse in the HAV-exposed group, although both groups improved after surgery. Multivariable linear regression revealed a significantly worse postoperative score and change in QuickDASH in HAV-exposed patients. There was no difference in satisfaction, but after surgery, the 5-level EuroQol-5D score was significantly worse in HAV-exposed patients. Conclusions Carpal tunnel release in HAV-exposed patients results in a significantly lower improvement in self-reported disability compared with patients without HAV exposure. This study provides important prognostic information for patients with previous HAV exposure undergoing carpal tunnel release. Type of study/level of evidence Prognostic III.

Background Hearing loss is one of the most prevalent worker health conditions worldwide. Although the effect of noise exposure on hearing is well researched, other workplace exposures may account for significant hearing loss. The aim of this review was to determine whether occupational hand–arm vibration exposure through use of power or pneumatic tools, independent of noise exposure, is associated with permanent hearing loss. Do workers suffer from hand–arm vibration–induced hearing loss? Methods Peer-reviewed articles published in English between 1981 and 2020 were identified through five online databases with five search keywords. Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, including online database search methodology, study selection, article exclusion, and assessment of potential study design confounders and biases, were followed. Results Database searches retrieved 697 articles. Fifteen articles that reported 17 studies met the criteria for review. All but two studies revealed statistically significant associations between occupational exposure to hand–arm vibration and hearing loss. The majority of the study results revealed associations between hand–arm vibration and hearing loss, independent of potential age and noise confounders. Conclusion Few studies have examined the association between occupational exposure to hand–arm vibration and hearing loss. Dose response data were limited as only one study measured vibration intensity and duration. Although the majority of studies identified statistically significant associations, causal relationships could not be determined. Further research using standardized and uniform measurement protocols is needed to confirm whether the association between occupational exposure to hand–arm vibration and permanent hearing loss is causal and the mechanism(s).

This paper is concerned with the numerical analysis of the equations given by the mechanics of the impact of a ball and a hand-arm system for two potential subjects male and female. The influence of the mass of the ball and its velocity on the values of the hand-arm joints reactions is studied.

The study aimed to assess the hand-arm vibration (HAV), noise exposure, and shift in hearing threshold (SHT) due to the prolonged use of hand tools used in three different handicraft occupations. D...

BackgroundTesting of vibration perception threshold (VPT) at the fingertips as a quantitative measure of tactile sensitivity is a commonly used tool in diagnosing hand–arm vibration syndrome. There is limited research on dose–response relationships between hand–arm vibration (HAV) exposure and VPT on an individual level.AimsAssess possible dose–response relationships on an individual level between HAV exposure and VPT at the fingertips.MethodsWe assessed average daily vibration exposure (m/s2A8) and cumulative lifetime HAV exposure for 104 participants from different departments in a road maintenance company based on vibration measurements and questionnaires. VPT was measured based on the technical method described in ISO 13091-1:2005 using octave frequencies 8–500 Hz. We investigated associations using linear regression models with significance level p≤0.05.ResultsThe participants were either exposed to rock drills (n=33), impact wrenches (n=52) or none of these tools (n=19). Exposure to rock drills and impact wrenches was associated with elevated VPT for all seven test frequencies in the second and fifth fingers of both hands. A dose–response with the daily exposure measure m/s2(A8) was found based on 1.2 m/s2(A8) for impact wrenches, and 5.4 m/s2(A8) for rock drills. A stronger association was found with the cumulative exposure for rock drills compared with impact wrenches, and for the second finger compared with the fifth finger.ConclusionsHAV exposure was associated with elevated VPT, also at exposure levels below the common exposure action value of 2.5 m/s2(A8). Lowering the HAV exposure can contribute to prevent increasing VPTs in these workers.

Background: Hand-arm bimanual intensive therapy (HABIT) has been shown to be an effective method for improving upper-extremity function. However, owing to ambiguity within the evidence of HABIT’s effects on hand function among children with unilateral spastic cerebral palsy (CP), this meta-analysis sought to elucidate whether the same was true in this patient population. Summary: A computerized database search yielded 468 studies. After meticulous scrutiny and screening of these studies according to the selection criteria, 4 full-text articles were included in the meta-analysis. All 4 studies underwent a methodological quality assessment according to the Physiotherapy Evidence Database Scale (PEDro), with a score of greater than 8. Five comparisons were then made involving the 4 selected randomized controlled trials (RCTs). The effect size was measured using the correlation coefficient (r value). The effect sizes of the individual studies were 0.006, 0.03, 0.04, 0.22, and 0.15. The total effect size was 0.06. Key Message: This meta-analysis determined that there is a trivial benefit using HABIT when compared to constraint-induced movement therapy or structured and unstructured bimanual therapy in pediatric patients with unilateral spastic CP. More RCTs are needed to substantiate our evidence.

Exposure to hand-arm vibration (HAV) among the labor force in the mining industry can result in permanent vibration diseases such as behavioral disorders, visual impairment, osteoporosis, pain (mostly in the hands, wrists, and shoulders), circulatory system disorders, and malnutrition. In this study, the vibration exposure of excavator operators working regularly in 25 different natural stone quarries was measured. In addition, the relationship between vibration exposure and rock properties was investigated. Gloved and ungloved vibration measurements were performed and revealed that antivibration gloves reduce excavator operators’ vibration exposure by 7.10–25.95%. Samples from each quarry were characterized with rock mechanics tests. The correlations between the hand-arm vibration measurements and the natural stone physical–mechanical properties (uniaxial compressive strength, Shore hardness, Knoop hardness, apparent density and total porosity) were determined to be over 70%. One finding of the study was that the health risk in excavators cannot be reduced sufficiently by the sole use of antivibration gloves. Furthermore, the excavation of any rock with a Knoop hardness above 121 is associated with an 81% risk of HAV. To increase awareness of the danger of vibration exposure for natural stone miners, training programs should be provided, and technical and operational changes should be implemented.

This controlled, exploratory laboratory study was conducted to measure hand-arm vibration (HAV) exposures when using a bucking bar fitted with three different handles: 1) a typical plastic handle, 2) a similarly designed handle with an aluminum core and a built-in dampening spring, and 3) a steel core handle with the same built-in spring. Using two experienced machinists, tri-axial HAV exposures were measured at the bucking bar handles; small, battery-powered, self-contained Inertial Measurement Units (IMUs) were used to measure the vibration transmitted through the tool operator’s left and right arms; and a wearable device worn on the operator’s right wrist estimated the HAV exposures occurring at the tool handle. The plastic handle produced the highest HAV exposures while the aluminum-spring and steel spring handles reduced exposures by 19% and 39%, respectively. On average, 74%, 65% and 40% of the tool-measured vibration was transmitted to the right hand, forearm and upper arm, respectively. The wrist mounted sensor appeared to accurately estimate HAV exposures measured at the hand-tool interface.

Operators of hand tractors are exposed to high levels of hand transmitted vibration (HTV). This vibration, which can be both irksome and hazardous to human health, is imparted to the operator via his or her hands and arms. However, a standardized method for measuring HTV of hand tractors has yet to be defined. The aim of the study was to present an experimental method for the investigation of the biodynamic response and vibration transmissibility of the hand-arm system during the operation of a hand tractor in a stationary mode. Measurements were performed with ten subjects using three grip forces and three handle vibration levels to examine the influences of the hand pressure and frequency on hand transmitted vibration (HTV). The results indicate that the tightness of grip on the handle influences the vibration response of the hand-arm system, especially at frequencies between 20 and 100 Hz. The transmission of lower frequencies in the hand-arm system was relatively unattenuated. In comparison, attenuation was found to be quite marked for higher frequencies during the operation of the hand tractor. The vibration transmissibility to different parts of the hand-arm system decreased with the increase of the distance from the vibration source. The proposed methodology contributes to the collection of consistent data for the evaluation of operator vibration exposure and the ergonomics development of hand tractors.

The objective of this study is to characterize the vibration responses of a handheld workpiece and the hand–arm system, which is an important step toward identifying and developing effective methods and technologies for controlling the vibration exposures to workers performing the grinding of handheld workpieces. This study established a method for measuring the vibration responses of the entire workpiece–hand–arm system; the vibration exposure of a worker holding and pressing a typical workpiece against a sanding belt or grinding wheel in order to shape the workpiece was simulated. This method was applied to measure the apparent mass and vibration transmissibility of the system under two different feed forces (15 N and 30 N) and six simulated grinding interfaces with different stiffness values. A major resonance was observed in each transmissibility spectrum of the workpiece, which was correlated with the major resonance of the impedance of the entire system. This resonant frequency depended primarily on the workpiece mass and the grinding interface stiffness, but the hand–arm system could substantially affect the resonance magnitude. The feed force also significantly affected the resonance frequency and magnitude. While increasing the feed force increased the overall vibration transmissibility on the hand–arm system, the transmissibility with respect to the workpiece was not significantly affected by the interface conditions. The implications of the results are discussed.

Blueberry production has skyrocketed in the past two decades due to an exponential increase in consumer demand around the world. Hand harvesters are used, avoiding damage to the fruit and increasing harvesting efficiency multifold when compared with that of hand-picking. The downside of these hand harvesters is their high Hand Arm Vibration (HAV), which is very dangerous for the worker and can cause hand-arm vibration syndrome (HAVS). The aim of this study is to propose a spring-based anti-vibration handle that can be attached to vibrating equipment (blueberry hand harvester). Four different parameters were measured for the developed spring-based handles: hand arm vibration, wrist posture, muscle activity, and subjective discomfort rating. Results have shown that the use of a spring-based handle can reduce HAV by 61.1%, which is within the exposure limit values (ELV) defined by the European Union.

In this investigation, the novel multi-axial vibration absorber is proposed to reduce the handle vibration of petrol engine grass trimmer. The proposed vibration absorber is designed using Dunkerley’s equation and fabricated for testing. The experimental modal analysis of absorber is conducted to find resonance frequencies of the absorber and to validate the results obtained from equations. The experimental tests are carried on grass trimmer with absorber attached near handle location to find effectiveness of absorber in reducing hand-arm vibrations in the x, y and z directions. The result indicated that the total vibration value measured at the handle of grass trimmer is reduced by substantial level with the attachment of multi-axial vibration absorber.

Background Non-automated tool handles transmit a large magnitude of vibration to operators' hands, causing discomfort and pain. Therefore, the need for a better handle design is a matter of prime concern to overcome musculoskeletal disorders such as hand-arm vibration syndrome. Objective This study aimed to examine the influence of handle shapes in reducing the transmission of hand-arm vibration. Methods Seven different handles were designed and fabricated using 3D printing technology at the SSN College of Engineering, with consideration for the anatomical shape of the hand. The frequency-weighted Root Mean Square (RMS) values of the vibration levels transmitted were recorded at the wrist of twelve subjects, unaffected by musculoskeletal disorders. Subjective ratings of vibration and comfort perception were measured using the Borg Scale of Perceived Exertion. Results The total vibration value (ahv) of each of the six novel prototype handles (B-G) was compared to that of the reference handle denoted handle-A. The vibration reductions for handles B to G respectively were 0.542 m/s2 (14.59%), 0.481 m/s2 (12.95%), 0.351 m/s2 (9.45%), 0.270 m/s2 (7.27%), 0.407 m/s2 (10.96%) and 0.192 m/s2 (5.17%). Conclusions A significant level of vibration reduction was achieved by the prototype handles. Qualitative feedback from the study subjects suggests that they were not aware of the levels of vibration being transmitted to the hand with each handle.

Limited information is currently available regarding the hand-arm vibration (HAV) exposure 5 for professional off-road cyclists. Previous reports have suggested that commuting and 6 recreational cyclists are at risk of exceeding exposure limit values (ELV) in a single ride. 7 Therefore, further investigation of HAV exposure in competitive mountain biking is 8 warranted. Partial and total eight hour exposure data (Ai(8), A(8), ms⁻²) were computed for a 9 national level mountain bike enduro competitions. Hand-arm vibrations were measured using 10 a tri-axial accelerometer recording at a frequency of 3.2 kHz mounted on the handlebar and 11 accelerations were quantified after frequency weighting filters were applied (Wh). The data 12 presented shows that HAV exposure during one day of competitive enduro mountain bike 13 racing exceeds ELV (mean race exposure = 5.84 ms⁻² , minimum = 5.47ms⁻² , maximum = 14 6.61ms⁻²) and is greater than the HAV exposure observed in recreational cycling. This 15 suggests that further work is required to determine the exposure associated with changes in 16 equipment, technique and international racing events in professional athletes.

A defective pavement surface discourages cyclists from selecting certain routes, and vibration exposure is a noticeable consequence of reduced path surface quality. Current asset management practice includes walkover surveys and cyclists reporting defects directly to the local authority. This research proposes the use of an instrumented probe bicycle to collect data for the assessment of pavement condition and rider comfort. Furthermore, the collection of hand–arm vibration exposure data is proposed as a means of assessing pavement surface condition and suitability. Hand–arm vibration exposure has been measured in compliance with BS EN ISO 5349-1:2001. Root-mean-square vibration total values, vibration dose value and exposure values (15, 30 and 60 min) are provided for 13·682 km of pavement surface in Edinburgh, Scotland. The vibration exposure values are compared to those recommended by EU Directive 2002/44/EC. Power spectral analysis is also performed to determine the power transferred to the cyclist’s hands and arms. The collated vibration data may be used as a means of assessing pavement surface condition. Such data may prove beneficial for local authority asset management associated with resurfacing or repair works.

In many developed countries and cities, the construction industry, which is a major economic pillar, is expanding at a rapid pace. In this context, the use of construction machines and vibrating tools for various construction activities is indispensable. With the increasing use of handheld vibrating equipment, construction workers are exposed to hand-arm vibration (HAV), which is a serious occupational risk for those who work with vibrating tools and machinery that cause vibration damage to the fingers, hands and arms. Long-term and chronic exposure to HAV, it may induce hand-arm vibration syndrome (HAVS), resulting in vascular, neurological and musculoskeletal disorders. HAVS causes permanent and irreversible damage, leading to a high level of disability and work impairment. Due to its severity, a pilot study of HAV is revisited in accordance with the existing exposure points system from the UK’s Health and Safety Executive. Two important factors are considered, namely worker’s age and local climate (e.g., temperature and humidity). A simple idea is proposed to optimize the applicability of the exposure points system to different age groups and climates. The findings of this human-based study may be used as a practical reference for policymakers and contractors.

Introduction This is a retrospective study exploring clinical effect of acupuncture and moxibustion on upper limb disorder induced by occupational hand-arm vibration disease (OHAVD), and preliminarily exploring mechanism of the effect. Methods 43 patients diagnosed with occupational HAVD were divided into experimental group (n = 21) and control group (n = 22). Before and after 4 weeks treatment, the occurrence of vibration-induced white finger(VWF) was observed, upper limb function was assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, based on which the DASH scores were determined, and the serum concentration of TNFα was detected using ELISA. Results Pre-treatment DASH score was not significantly different between two groups, but post-treatment score was significantly lower in experimental group than in control group (21.94 ± 5.79vs.35.87 ± 3.80, p Conclusions Combination of acupuncture and moxibustion may be an effective treatment for occupational HAVD, the mechanism is possibly related to reduction of the serum TNFα levels.

BackgroundCurrent PPE practices in UK intensive care units involve “sessional” gown use. This protects staff, but puts patients at risk of nosocomial infection via PPE gowns. Anecdotal reports of such infections in ITUs during Covid are frequent. We therefore explored the use of short-sleeved gowns with hand and arm hygiene as an alternative to sessional gowns.MethodsITU Staff were invited for simulation suite training in Covid intubation and proning. They were trained in a specific hand and arm washing technique before performing simulated tasks using both standard and modified (short sleeved) PPE. Fluorescent powder was used to simulate micro-organisms, and detected using standardised photos under U/V light. Teams of staff were randomised to use standard or modified PPE first. Individuals were questioned about their feeling of personal safety, comfort and the patient’s safety at 4 intervals.Results68 staff and 17 proning volunteers were studied in 17 sessions. Modified PPE completely prevented staff contamination during Covid intubation, which occurred in 30/67 staff wearing standard PPE (p = 0.0029, McNemar). Conversely, proning volunteers were contaminated by staff in 15/17 sessions with standard PPE and in 1/17 with modified PPE (P = 0.0227 McNemar). Impressions of staff comfort were superior with modified PPE (p< 0.001, t-test); personal safety scored higher with standard PPE, but the difference decreased during the session (pConclusionsModified PPE using short sleeves and hand/arm cleansing appears superior to standard PPE with sessional gowns in preventing transfer of contamination between staff and patients. A clinical trial of this strategy is merited.

Contains fulltext : 241928.pdf (Publisher’s version ) (Open Access) OBJECTIVE: To preoperatively plan skin incision in the case of the first Dutch bilateral hand-arm transplantation. BACKGROUND: A bilateral hand-arm transplantation has been performed for the first time in the Netherlands in 2019. In the context of preparation for this surgical procedure, the optimal patient-specific skin flap was determined. Skin flaps should be properly matched between donor and recipient to ensure sufficient tissue for the approximation of skin over the tendon anastomosis, adequate distal tip perfusion, and esthetics. METHODS: Preoperatively, stereophotogrammetry was obtained from the upper extremities of the patient and a volunteer with similar body physique. Skin flap dimensions were determined for each extremity, which resulted in patient-specific incision patterns. Combining this digital information yielded practical skin incision guides for both the donor and acceptor arms. Finally, the computer-aided designs were 3D printed. RESULTS: The 3D prints were convenient to utilize in both shaping the donor flaps as in preparing the acceptor extremities, taking only a few seconds during precious ischemia time. There was sufficient skin flap perfusion, and the wound-healing followed an uncomplicated course. No corrections were made to the initial skin incisions. CONCLUSIONS: Three-dimensional printed templates were successfully utilized in the first Dutch bilateral hand-arm transplantation. We believe its usage increased time efficiency, improved the match of skin flaps in donor and recipient arms, and allowed us to control the amount of skin surplus without skin flap tip necrosis. In these procedures where time is of the essence, we believe preoperative planning is imperative for its success.

In order to investigate the effects of hand-arm posture, grip force, push force, and vibration excitation intensity on the mechanical impedance of human hand-arm system, a test system with a self-developed vibration handle has been prepared. Based on the testing system, the mechanical impedance of the hand-arm system of seven Chinese adult males were tested and calculated under the random vibration excitation with the frequency of 10–1000 Hz. The results reveal that when the frequency is lower (100 Hz), the hand-arm posture seems to have no obvious effect on the mechanical impedance. Higher grip or push force would increase the frequency corresponding to the peak value of the mechanical impedance and often correspond to a higher mechanical impedance in a specific frequency range (30–200 Hz). When the frequency is lower (

Objectives To assess the hazard of tool vibrations, we need valid exposure measurements. The use of hand-attached accelerometers (vibration sensors) to measure hand-arm vibrations (HAVs) has become a popular approach. However, according to International Standard ISO 5349-2, the preferred attachment of accelerometers is at the tool handle. We compared measures of HAV between hand- and tool-attached accelerometers in rock drilling. Methods We measured HAV in five rock drillers using jackleg drills in normal working operations with simultaneous measures of both hand-attached and tool-attached accelerometers. Five to seven measurement cycles of 15 s were executed on each worker, resulting in a total of 29 measurement cycles. To identify possible differences in working technique, we recorded videos of tool handle handgrips during drilling. Results There was a significant difference (9.5 m s−2; P ≤ 0.05) in vibration magnitudes measured by the tool-attached accelerometers compared with the hand-attached accelerometers. The hand-attached accelerometer showed a lower vibration magnitude for all workers (range of difference: 2.3–14.6). The variation between the two accelerometer attachments was larger between workers than within workers (ICC = 0.68). Conclusions For measurements of HAV from jackleg drills, the use of hand-attached accelerometers may cause a lower recorded vibration level compared with tool-attached accelerometers. This difference is likely to vary depending on how workers grip the tool handle, and a misclassification of exposure will occur if workers grip the tool handle in a way that makes the accelerometer lose contact with the vibrating surface. Individual differences in how workers grip the tool handles should be considered when assessing HAV.

The harvesting robot is usually composed of mobile platform, manipulator, end-effector, vision system, and control system. The mobile harvesting operation of the fruits and vegetables needs complex coordination among different modules. As a hand–arm system which handles the fruit and vegetable targets directly, the principle of the harvesting action, the ability of perception and judgment, and the hand–arm coordination are the key to ensure the speedy damage-free harvesting. The development of new-principle and new-structure damage-free harvesting hand–arm system has important academic and practical significance.

We present a novel learning and control framework that combines artificial neural networks with online trajectory optimization to learn dexterous manipulation skills from human demonstration and to transfer the learned behaviors to real robots. Humans can perform the demonstrations with their own hands and with real objects. An instrumented glove is used to record motions and tactile data. Our system learns neural control policies that generalize to modified object poses directly from limited amounts of demonstration data. Outputs from the neural policy network are combined at runtime with kinematic and dynamic safety and feasibility constraints as well as a learned regularizer to obtain commands for a real robot through online trajectory optimization. We test our approach on multiple tasks and robots.

Aim: To investigate the efficacy of Constraint induced movement therapy (CIMT) versus Hand–arm bimanual intensive training (HABIT) on postural control during reaching with the affected arm and reaching quality in sitting children with hemiplegia. Methods: Forty-Two children; twenty normal children and twenty –two with spastic hemiplegia were recruited for participation in the study, hemiplegic children were randomized to the CIMT or HABIT group. Two hemiplegic children were excluded. Their age ranged from four to eight years old. The primary outcome: postural control that was evaluated using Qualysis motion AB system. Secondary outcome: reaching quality that was assessed using Peabody developmental motor scales (version-2) before and after four weeks of interventions that were provided 6days/week for 3 hours/day. Results: The results of this study revealed that there was significant improvement (p < .05) in all measured dependent variables in the post-treatment condition compared with the pre-treatment in both study groups with preference for group (B). Conclusions: Both techniques have a positive influence on postural control and quality of reaching and it would be better to combine both of them in treatment programs.

Objective: To investigate whether low molecular organic biomarkers could be identified in blood samples from vibration exposed workers using a metabolomics. Methods: The study population consisted of 38 metalworkers. All participants underwent a standardized medical examination. Blood samples were collected before and after work shift and analyzed with gas chromatography time-of-flight mass spectrometry. Multivariate modeling (orthogonal partial least-squares analysis with discriminant analysis [OPLS-DA]) were used to verify differences in metabolic profiles. Results: Twenty-two study participants reported vascular symptoms judged as vibration-related. The metabolic profile from participants with vibration-induced white fingers (VWF) was distinctly separated from participants without VWF, both before and after vibration exposure. Conclusion: Metabolites that differed between the groups were identified both before and after exposure. Some of these metabolites might be indicators of health effects from exposure to vibrations. This is the first time that a metabolomic approach has been used in workers exposed to vibrations.

This research aims to evaluate the vibration transmitted to the hand-arm system by four electric portable harvesters, mainly different for kinematics of the harvester head (synchronous or opposite), rod material (aluminum or carbon fiber), and rod configuration (fixed length or telescopic). Models with telescopic rods were tested at minimum and maximum length. All models were driven at two running frequencies: 1050 and 1200 oscillations per minute. Accelerations were measured at different times and at no-load condition in two points, 0.5 m apart, next to the hand positions. The results showed that the main difference in acceleration values was due to the kinematics of the harvester heads: 21.80 versus 6.27 m s−2 for synchronous and opposite movement, respectively. Differences between rod configurations were on average not statistical significant, as well as those between running frequencies. For each machine, acceleration values in front position (on the rod) were higher than in rear position (near the hand-grip). The differences in kinematics of the harvester head also affected acceleration component values: acceleration was higher along x-axis (19.27 m s−2) when arms carrying sticks moved synchronously and higher along y-axis (5.11 m s−2) when arms moved in opposition.

When using a tool with a robotic hand-arm system, the stiffness at the grasped object plays a key role in the interaction with the environment, allowing the successful execution of the task. However, the rapidly increasing use of under-actuated hands in robotic systems due to their robustness and simplicity of control, pose limitations to the achievable object-level stiffness. Indeed, due to the serial coupling of the hand and the arm, the resulting object-level stiffness is determined by the most compliant of both elements. To address this problem, we propose a novel controller that takes into account the limited achievable geometry of the object stiffness ellipsoid given by a hand with under-actuation constraints, and exploits the contribution of the robotic arm in reshaping the final stiffness towards the desired profile. The under-actuation is illustrated by a coordinated stiffening of the hand fingers. The proposed method is experimentally validated by a hand-arm system performing a peg-in-hole task.

The objective of this study was to develop a vibration model of a grinding machine-workpiece-hand-arm system. A lumped-parameter model structure of the system was proposed, and its major parameters were determined using the mechanical impedance measured at the grinding point of a typical workpiece (golf club head) held by two hands and referenced to the vibration transmissibility spectra measured at the wrist and on the upper arm of human subjects. The model reasonably predicted the vibration transmissibility spectra measured on the club head and the driving-point response function when the grinding contact stiffness was below a certain value. This suggests that the model is acceptable not only to enhance the understanding of the system responses, but also to explore some engineering methods for controlling vibration exposures during the grinding process. The identified model parameters reveal that the major resonance of the handheld workpiece depends primarily on its mass and grinding contact stiffness. The feed force applied in the grinding process can substantially affect the grinding contact stiffness; as a result, it can significantly influence the resonance. Vibration-reducing gloves can marginally increase the workpiece resonance, but these gloves can reduce some vibration transmitted to the hand-arm system. This study also clarified an important mechanism for the prediction errors of linear human vibration models, which is useful to further improve human vibration modeling.

During recent years the number of tennis athletes has increased significantly. When playing tennis, the human body is exposed to many situations which can lead to human injuries, such as the so-called tennis elbow (lateral epicondylitis). In this work a biomechanical analysis of tennis athletes, particularly during the service, was performed, considering three different types of over-grip and the presence of one anti-vibrator device. One part of the study evaluates the exposure to hand-arm vibration of the athlete, based on the European Directive 2002/44/EC concerning the minimum health and safety requirements, regarding the exposure of workers to risks from physical agents. The second part of the study considers an infrared thermography analysis in order to identify signs of risk of injury, particularly tennis elbow, one of the most common injuries in this sport. The results show that the presence of the anti-vibrator influences the vibration values greatly in the case of athletes with more experience and also for athletes with less performance. The presence of the Cork and/or Tourna on the racket grip does not have any significant effect on the hand-arm vibration (HAV), similarly in the case of athletes with the best performance and athletes with less technique. The results indicated that the infrared thermography technique may be used to identify the risk of injuries in tennis players.