Doppler ultrasound exam of an arm or leg

MedlinePlus

... page: //medlineplus.gov/ency/article/003775.htm Doppler ultrasound exam of an arm or leg To use ... this page, please enable JavaScript. This test uses ultrasound to look at the blood flow in the ...

Changes in arm-hand function and arm-hand skill performance in patients after stroke during and after rehabilitation

PubMed Central

Smeets, Rob Johannes Elise Marie; Seelen, Henk Alexander Maria

2017-01-01

Background Arm-hand rehabilitation programs applied in stroke rehabilitation frequently target specific populations and thus are less applicable in heterogeneous patient populations. Besides, changes in arm-hand function (AHF) and arm-hand skill performance (AHSP) during and after a specific and well-described rehabilitation treatment are often not well evaluated. Method This single-armed prospective cohort study featured three subgroups of stroke patients with either a severely, moderately or mildly impaired AHF. Rehabilitation treatment consisted of a Concise_Arm_and_hand_ Rehabilitation_Approach_in_Stroke (CARAS). Measurements at function and activity level were performed at admission, clinical discharge, 3, 6, 9 and 12 months after clinical discharge. Results Eighty-nine stroke patients (M/F:63/23; mean age:57.6yr (+/-10.6); post-stroke time:29.8 days (+/-20.1)) participated. All patients improved on AHF and arm-hand capacity during and after rehabilitation, except on grip strength in the severely affected subgroup. Largest gains occurred in patients with a moderately affected AHF. As to self-perceived AHSP, on average, all subgroups improved over time. A small percentage of patients declined regarding self-perceived AHSP post-rehabilitation. Conclusions A majority of stroke patients across the whole arm-hand impairment severity spectrum significantly improved on AHF, arm-hand capacity and self-perceived AHSP. These were maintained up to one year post-rehabilitation. Results may serve as a control condition in future studies. PMID:28614403

Central and peripheral hemodynamics in exercising humans: leg vs arm exercise.

PubMed

Calbet, J A L; González-Alonso, J; Helge, J W; Søndergaard, H; Munch-Andersen, T; Saltin, B; Boushel, R

2015-12-01

In humans, arm exercise is known to elicit larger increases in arterial blood pressure (BP) than leg exercise. However, the precise regulation of regional vascular conductances (VC) for the distribution of cardiac output with exercise intensity remains unknown. Hemodynamic responses were assessed during incremental upright arm cranking (AC) and leg pedalling (LP) to exhaustion (Wmax) in nine males. Systemic VC, peak cardiac output (Qpeak) (indocyanine green) and stroke volume (SV) were 18%, 23%, and 20% lower during AC than LP. The mean BP, the rate-pressure product and the associated myocardial oxygen demand were 22%, 12%, and 14% higher, respectively, during maximal AC than LP. Trunk VC was reduced to similar values at Wmax. At Wmax, muscle mass-normalized VC and fractional O2 extraction were lower in the arm than the leg muscles. However, this was compensated for during AC by raising perfusion pressure to increase O2 delivery, allowing a similar peak VO2 per kg of muscle mass in both extremities. In summary, despite a lower Qpeak during arm cranking the cardiovascular strain is much higher than during leg pedalling. The adjustments of regional conductances during incremental exercise to exhaustion depend mostly on the relative intensity of exercise and are limb-specific. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Intensity of leg and arm training after primary middle-cerebral-artery stroke: a randomised trial.

PubMed

Kwakkel, G; Wagenaar, R C; Twisk, J W; Lankhorst, G J; Koetsier, J C

1999-07-17

We investigated the effects of different intensities of arm and leg rehabilitation training on the functional recovery of activities of daily living (ADL), walking ability, and dexterity of the paretic arm, in a single-blind randomised controlled trial. Within 14 days after stroke onset, 101 severely disabled patients with a primary middle-cerebral-artery stroke were randomly assigned to: a rehabilitation programme with emphasis on arm training; a rehabilitation programme with emphasis on leg training; or a control programme in which the arm and leg were immobilised with an inflatable pressure splint. Each treatment regimen was applied for 30 min, 5 days a week during the first 20 weeks after stroke. In addition, all patients underwent a basic rehabilitation programme. The main outcome measures were ability in ADL (Barthel index), walking ability (functional ambulation categories), and dexterity of the paretic arm (Action Research arm test) at 6, 12, 20, and 26 weeks. Analyses were by intention to treat. At week 20, the leg-training group (n=31) had higher scores than the control group (n=37) for ADL ability (median 19 [IQR 16-20] vs 16 [10-19], p<0.05), walking ability (4 [3-5] vs 3 [1-4], p<0.05), and dexterity (2 [0-56] vs 0 [0-2], p<0.01). The arm-training group (n=33) differed significantly from the control group only in dexterity (9 [0-39] vs 0 [0-2], p<0.01). There were no significant differences in these endpoints at 20 weeks between the arm-training and leg-training groups. Greater intensity of leg rehabilitation improves functional recovery and health-related functional status, whereas greater intensity of arm rehabilitation results in small improvements in dexterity, providing further evidence that exercise therapy primarily induces treatment effects on the abilities at which training is specifically aimed.

Early manifestation of arm-leg coordination during stepping on a surface in human neonates.

PubMed

La Scaleia, Valentina; Ivanenko, Y; Fabiano, A; Sylos-Labini, F; Cappellini, G; Picone, S; Paolillo, P; Di Paolo, A; Lacquaniti, F

2018-04-01

The accomplishment of mature locomotor movements relies upon the integrated coordination of the lower and upper limbs and the trunk. Human adults normally swing their arms and a quadrupedal limb coordination persists during bipedal walking despite a strong corticospinal control of the upper extremities that allows to uncouple this connection during voluntary activities. Here we investigated arm-leg coordination during stepping responses on a surface in human neonates. In eight neonates, we found the overt presence of alternating arm-leg oscillations, the arms moving up and down in alternation with ipsilateral lower limb movements. These neonates moved the diagonal limbs together, and the peak of the arm-to-trunk angle (i.e., maximum vertical excursion of the arm) occurred around the end of the ipsilateral stance phase, as it occurs during typical adult walking. Although episodes of arm-leg coordination were sporadic in our sample of neonates, their presence provides significant evidence for a neural coupling between the upper and lower limbs during early ontogenesis of locomotion in humans.

Composite Tissue Transplant of Hand or Arm: A Health Technology Assessment.

PubMed

2016-01-01

Injuries to arms and legs following severe trauma can result in the loss of large regions of tissue, disrupting healing and function and sometimes leading to amputation of the damaged limb. People experiencing amputations of the hand or arm could potentially benefit from composite tissue transplant, which is being performed in some countries. Currently, there are no composite tissue transplant programs in Canada. We conducted a systematic review of the literature, with no restriction on study design, examining the effectiveness and cost-effectiveness of hand and arm transplant. We assessed the overall quality of the clinical evidence with GRADE. We developed a Markov decision analytic model to determine the cost-effectiveness of transplant versus standard care for a healthy adult with a hand amputation. Incremental cost-effectiveness ratios (ICERs) were calculated using a 30-year time horizon. We also estimated the impact on provincial health care costs if these transplants were publicly funded in Ontario. Compared to pre-transplant function, patients' post-transplant function was significantly better. For various reasons, 17% of transplanted limbs were amputated, 6.4% of patients died within the first year after the transplant, and 10.6% of patients experienced chronic rejections. GRADE quality of evidence for all outcomes was very low. In the cost-effectiveness analysis, single-hand transplant was dominated by standard care, with increased costs ($735,647 CAD vs. $61,429) and reduced quality-adjusted life-years (QALYs) (10.96 vs. 11.82). Double-hand transplant also had higher costs compared with standard care ($633,780), but it had an increased effectiveness of 0.17 QALYs, translating to an ICER of $3.8 million per QALY gained. In most sensitivity analyses, ICERs for bilateral hand transplant were greater than $1 million per QALY gained. A hand transplant program would lead to an estimated annual budget impact of $0.9 million to $1.2 million in the next 3 years

Composite Tissue Transplant of Hand or Arm: A Health Technology Assessment

PubMed Central

Lambrinos, Anna; Xie, Xuanqian; Higgins, Caroline; Holubowich, Corinne

2016-01-01

Background Injuries to arms and legs following severe trauma can result in the loss of large regions of tissue, disrupting healing and function and sometimes leading to amputation of the damaged limb. People experiencing amputations of the hand or arm could potentially benefit from composite tissue transplant, which is being performed in some countries. Currently, there are no composite tissue transplant programs in Canada. Methods We conducted a systematic review of the literature, with no restriction on study design, examining the effectiveness and cost-effectiveness of hand and arm transplant. We assessed the overall quality of the clinical evidence with GRADE. We developed a Markov decision analytic model to determine the cost-effectiveness of transplant versus standard care for a healthy adult with a hand amputation. Incremental cost-effectiveness ratios (ICERs) were calculated using a 30-year time horizon. We also estimated the impact on provincial health care costs if these transplants were publicly funded in Ontario. Results Compared to pre-transplant function, patients’ post-transplant function was significantly better. For various reasons, 17% of transplanted limbs were amputated, 6.4% of patients died within the first year after the transplant, and 10.6% of patients experienced chronic rejections. GRADE quality of evidence for all outcomes was very low. In the cost-effectiveness analysis, single-hand transplant was dominated by standard care, with increased costs ($735,647 CAD vs. $61,429) and reduced quality-adjusted life-years (QALYs) (10.96 vs. 11.82). Double-hand transplant also had higher costs compared with standard care ($633,780), but it had an increased effectiveness of 0.17 QALYs, translating to an ICER of $3.8 million per QALY gained. In most sensitivity analyses, ICERs for bilateral hand transplant were greater than $1 million per QALY gained. A hand transplant program would lead to an estimated annual budget impact of $0.9 million to $1

Changes in kinematics and arm-leg coordination during a 100-m breaststroke swim.

PubMed

Oxford, Samuel W; James, Rob S; Price, Michael J; Payton, Carl J; Duncan, Michael J

2017-08-01

The purpose of this study was to compare arm-leg coordination and kinematics during 100 m breaststroke in 26 (8 female; 18 male) specialist breaststroke swimmers. Laps were recorded using three 50-Hz underwater cameras. Heart rate and blood lactate were measured pre- and post-swim. Arm-leg coordination was defined using coordination phases describing continuity between recovery and propulsive phases of upper and lower limbs: coordination phase 1 (time between end of leg kick and start of the arm pull phases); and coordination phase 2 (time between end of arm pull and start of leg kick phases). Duration of stroke phases, coordination phases, swim velocity, stroke length (SL), stroke rate (SR) and stroke index (SI) were analysed during the last three strokes of each lap that were unaffected by turning or finishing. Significant changes in velocity, SI and SL (P < 0.05) were found between laps. Both sexes showed significant increase (P < 0.05) in heart rate and blood lactate pre- to post-swim. Males had significantly (P < 0.01) faster swim velocities resulting from longer SLs (P = 0.016) with no difference in SR (P = 0.064). Sex differences in kinematic parameters can be explained by anthropometric differences providing males with increased propelling efficiency.

Relative Contribution of Arms and Legs in 30 s Fully Tethered Front Crawl Swimming

PubMed Central

Morouço, Pedro G.; Marinho, Daniel A.; Izquierdo, Mikel; Neiva, Henrique; Marques, Mário C.

2015-01-01

The relative contribution of arm stroke and leg kicking to maximal fully tethered front crawl swimming performance remains to be solved. Twenty-three national level young swimmers (12 male and 11 female) randomly performed 3 bouts of 30 s fully tethered swimming (using the whole body, only the arm stroke, and only the leg kicking). A load-cell system permitted the continuous measurement of the exerted forces, and swimming velocity was calculated from the time taken to complete a 50 m front crawl swim. As expected, with no restrictions swimmers were able to exert higher forces than that using only their arm stroke or leg kicking. Estimated relative contributions of arm stroke and leg kicking were 70.3% versus 29.7% for males and 66.6% versus 33.4% for females, with 15.6% and 13.1% force deficits, respectively. To obtain higher velocities, male swimmers are highly dependent on the maximum forces they can exert with the arm stroke (r = 0.77, P < 0.01), whereas female swimmers swimming velocity is more related to whole-body mean forces (r = 0.81, P < 0.01). The obtained results point that leg kicking plays an important role over short duration high intensity bouts and that the used methodology may be useful to identify strength and/or coordination flaws. PMID:26539511

Effects of combined high intensity arm and leg training on performance and cardio-respiratory measures.

PubMed

Zinner, Christoph; Sperlich, Billy; Born, Dennis-Peter; Michels, Guido

2017-01-01

The purpose of this study was to investigate the effects of combined arm and leg high-intensity low-volume interval training (HIITarm+leg) on maximal oxygen uptake, myocardial measures (i.e. stroke volume, cardiac output, ejection fraction), Tissue Oxygenation Index (TOI) of the vastus lateralis and triceps brachii, as well as power output in comparison to leg HIIT (HIITleg) only. The 20 healthy, male and female volunteers completed six sessions of either HIITleg on a cycle ergometer or HIITarm+leg on an arm and leg cycle ergometer. During pre- and post-testing, the volunteers completed a submaximal and incremental test to exhaustion on a cycle ergometer. Magnitude based interference revealed likely to very likely beneficial effects for HIITarm+leg compared to HIITleg in maximal oxygen uptake, cardiac measures as well peak power output. The TOI following HIITarm+leg demonstrated likely to very likely increased oxygenation in the triceps brachii or the vastus lateralis when compared to HIITleg. The results suggest that six sessions of HIITarm+leg may likely to very likely improve maximal oxygen uptake, some inotropy-related cardiac measures with improved tissue oxygenation of the triceps brachii and vastus lateralis muscles resulting in greater leg peak power output.

Hand-transmitted vibration and biodynamic response of the human hand-arm: a critical review.

PubMed

Dong, R G; Rakheja, S; Schopper, A W; Han, B; Smutz, W P

2001-01-01

Hand-arm vibration syndrome (HAVS) has been associated with prolonged exposure to vibration transmitted to the human hand-arm system from hand-held power tools, vibrating machines, or hand-held vibrating workpieces. The biodynamic response of the human hand and arm to hand transmitted vibration (HTV) forms an essential basis for effective evaluations of exposures, vibration-attenuation mechanisms, and potential injury mechanisms. The biodynamic response to HTV and its relationship to HAVS are critically reviewed and discussed to highlight the advances and the need for further research. In view of its strong dependence on the nature of HTV and the lack of general agreement on the characteristics of HTV, the reported studies are first reviewed to enhance an understanding of HTV and related issues. The characteristics of HTV and relevant unresolved issues are discussed on the basis of measured data, proposed standards, and measurement methods, while the need for further developments in measurement systems is emphasized. The studies on biodynamic response and their findings are grouped into four categories based on the methodology used and the objective. These include studies on (1) through-the-hand-arm response, expressed in terms of vibration transmissibility; (2) to-the-hand response, expressed in terms of the force-motion relationship of the hand-arm system; (3) to-the-hand biodynamic response function, expressed in terms of vibration energy absorption; and (4) computer modeling of the biodynamic response characteristics.

Development of exercise-induced arm-leg blood pressure gradient and abnormal arterial compliance in patients with repaired coarctation of the aorta.

PubMed

Markham, Larry W; Knecht, Sandra K; Daniels, Stephen R; Mays, Wayne A; Khoury, Philip R; Knilans, Timothy K

2004-11-01

Often, the lack of systemic arterial hypertension and the lack of a resting arm-leg blood pressure gradient are used to assess the adequacy of the anatomic result after intervention for coarctation of the aorta (CoA). Some patients with no arm-leg gradient at rest may develop a gradient with exercise, leading caregivers to question the success of the repair. It is not clear what the prevalence is of patients who have undergone a successful intervention for CoA and have no arm-leg gradient at rest but develop a significant gradient with exercise and which factors may predict the development of an arm-leg gradient with exercise. This study evaluates the prevalence and predictors of an exercise-induced arm-leg gradient in subjects who have undergone an apparently successful intervention for CoA.

Cardiovascular control during concomitant dynamic leg exercise and static arm exercise in humans

PubMed Central

Strange, S

1999-01-01

Skeletal muscle blood flow is thought to be determined by a balance between sympathetic vasoconstriction and metabolic vasodilatation. The purpose of this study was to assess the importance of high levels of sympathetic vasoconstrictor activity in control of blood flow to human skeletal muscle during dynamic exercise.Muscle sympathetic nerve activity to the exercising leg was increased by static or static ischaemic arm exercise added to on-going dynamic leg exercise. Ten subjects performed light (20 W) or moderate (40 W) dynamic knee extension for 6 min with one leg alone or concomitant with bilateral static handgrip at 20% of maximal voluntary contraction force with or without forearm muscle ischaemia or post-exercise forearm muscle ischaemia.Muscle sympathetic nerve activity was measured by microneurography (peroneal nerve) and leg muscle blood flow by a constant infusion thermodilution technique (femoral vein).Activation of an exercise pressor reflex from the arms, causing a 2- to 4-fold increase in muscle sympathetic nerve activity and a 15–32% increase in mean arterial blood pressure, did not affect blood flow to the dynamically exercising leg muscles at any level of leg exercise. Leg vascular conductance was reduced in line with the higher perfusion pressure.The results demonstrate that the vasoconstrictor effects of high levels of muscle sympathetic nerve activity does not affect blood flow to human skeletal muscle exercising at moderate intensities. One question remaining is whether the observed decrease in muscle vascular conductance is the result of sympathetic vasoconstriction or metabolic autoregulation of muscle blood flow. PMID:9831733

The Effects of Leg Kick on Swimming Speed and Arm-Stroke Efficiency in the Front Crawl.

PubMed

Silveira, Ricardo Peterson; de Souza Castro, Flávio Antônio; Figueiredo, Pedro; Vilas-Boas, João Paulo; Zamparo, Paola

2017-07-01

To analyze the effects of swimming pace on the relative contribution of leg kick to swimming speed and to compare arm-stroke efficiency (ηF) assessed when swimming with the arms only (SAO) and while swimming front crawl (FCS) using individual and fixed adjustments to arm-stroke and leg-kick contribution to forward speed. Twenty-nine master swimmers (21 men, 8 women) performed SAO and FCS at 6 self-selected speeds from very slow to maximal. The average swimming speed (v), stroke frequency (SF), and stroke length (SL) were assessed in the central 10 m of the swimming pool. Then, a 2nd-order polynomial regression was used to obtain values of v at paired SF. The percentage difference in v between FCS and SAO, for each paired SF, was used to calculate the relative contributions of the arm stroke (AC) and leg kick (LC) to FCS. Then ηF was calculated using the indirect "paddle-wheel" approach in 3 different ways: using general, individual, and no adjustments to AC. The LC increased with SF (and speed) from -1% ± 4% to 11% ± 1% (P < .05). At the lower FCS speeds, ηF calculated using general adjustments was lower than ηF calculated using individual adjustments (P < .05), but differences disappear at the fastest speeds. Finally, ηF calculated using individual adjustments to LC in the FCS condition did not differ with ηF assessed in the SAO condition at all the investigated speeds. The relative contributions of the arm stroke and leg kick should be individually estimated to reduce errors when calculating arm-stroke efficiency at different speeds and in different swimmers.

Left-handed skeletally mature baseball players have smaller humeral retroversion in the throwing arm than right-handed players.

PubMed

Takenaga, Tetsuya; Goto, Hideyuki; Sugimoto, Katsumasa; Tsuchiya, Atsushi; Fukuyoshi, Masaki; Nakagawa, Hiroki; Nozaki, Masahiro; Takeuchi, Satoshi; Otsuka, Takanobu

2017-12-01

It is known that the humeral retroversion of baseball players is greater in the throwing arm than in the nonthrowing arm. An investigation measuring dry bone specimens also showed that the right humerus had greater retroversion than the left. Considering these facts, it was hypothesized that humeral retroversion would differ between right- and left-handed players. This study aimed to compare the bilateral humeral retroversion between right- and left-handed skeletally mature baseball players. We investigated 260 (196 right-handed and 64 left-handed) male baseball players who belonged to a college or amateur team. Bilateral humeral retroversion was assessed using an ultrasound-assisted technique (humeral torsion angle [HTA]) as described by previous studies. Analysis of covariance, adjusted for handedness and baseball position, assessed the effect of throwing arm dominance on HTA. In comparison of the throwing arm, HTA was significantly smaller in left-handed (left humerus) than in right-handed (right humerus) players (77° vs. 81°; P < .001). In comparison of the nonthrowing arm, HTA was significantly greater in left-handed (right humerus) than in right-handed (left humerus) players (73° vs. 69°; P < .001). The mean side-to-side difference of HTA was significantly smaller in left-handed than in right-handed players (3° vs. 12°; P < .001). Humeral retroversion of left-handed skeletally mature baseball players was significantly smaller in the throwing arm, greater in the nonthrowing arm, and smaller in side-to-side differences than that of right-handed players. These findings may be key to understanding some of the biomechanical differences between right- and left-handed baseball players. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Development of PIMAL: Mathematical Phantom with Moving Arms and Legs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akkurt, Hatice; Eckerman, Keith F.

2007-05-01

The computational model of the human anatomy (phantom) has gone through many revisions since its initial development in the 1970s. The computational phantom model currently used by the Nuclear Regulatory Commission (NRC) is based on a model published in 1974. Hence, the phantom model used by the NRC staff was missing some organs (e.g., neck, esophagus) and tissues. Further, locations of some organs were inappropriate (e.g., thyroid).Moreover, all the computational phantoms were assumed to be in the vertical-upright position. However, many occupational radiation exposures occur with the worker in other positions. In the first phase of this work, updates onmore » the computational phantom models were reviewed and a revised phantom model, which includes the updates for the relevant organs and compositions, was identified. This revised model was adopted as the starting point for this development work, and hence a series of radiation transport computations, using the Monte Carlo code MCNP5, was performed. The computational results were compared against values reported by the International Commission on Radiation Protection (ICRP) in Publication 74. For some of the organs (e.g., thyroid), there were discrepancies between the computed values and the results reported in ICRP-74. The reasons behind these discrepancies have been investigated and are discussed in this report.Additionally, sensitivity computations were performed to determine the sensitivity of the organ doses for certain parameters, including composition and cross sections used in the simulations. To assess the dose for more realistic exposure configurations, the phantom model was revised to enable flexible positioning of the arms and legs. Furthermore, to reduce the user time for analyses, a graphical user interface (GUI) was developed. The GUI can be used to visualize the positioning of the arms and legs as desired posture is achieved to generate the input file, invoke the computations, and extract the

Liposuction for Advanced Lymphedema: A Multidisciplinary Approach for Complete Reduction of Arm and Leg Swelling.

PubMed

Boyages, John; Kastanias, Katrina; Koelmeyer, Louise A; Winch, Caleb J; Lam, Thomas C; Sherman, Kerry A; Munnoch, David Alex; Brorson, Håkan; Ngo, Quan D; Heydon-White, Asha; Magnussen, John S; Mackie, Helen

2015-12-01

This research describes and evaluates a liposuction surgery and multidisciplinary rehabilitation approach for advanced lymphedema of the upper and lower extremities. A prospective clinical study was conducted at an Advanced Lymphedema Assessment Clinic (ALAC) comprised of specialists in plastic surgery, rehabilitation, imaging, oncology, and allied health, at Macquarie University, Australia. Between May 2012 and 31 May 2014, a total of 104 patients attended the ALAC. Eligibility criteria for liposuction included (i) unilateral, non-pitting, International Society of Lymphology stage II/III lymphedema; (ii) limb volume difference greater than 25 %; and (iii) previously ineffective conservative therapies. Of 55 eligible patients, 21 underwent liposuction (15 arm, 6 leg) and had at least 3 months postsurgical follow-up (85.7 % cancer-related lymphedema). Liposuction was performed under general anesthesia using a published technique, and compression garments were applied intraoperatively and advised to be worn continuously thereafter. Limb volume differences, bioimpedance spectroscopy (L-Dex), and symptom and functional measurements (using the Patient-Specific Functional Scale) were taken presurgery and 4 weeks postsurgery, and then at 3, 6, 9, and 12 months postsurgery. Mean presurgical limb volume difference was 45.1 % (arm 44.2 %; leg 47.3 %). This difference reduced to 3.8 % (arm 3.6 %; leg 4.3 %) by 6 months postsurgery, a mean percentage volume reduction of 89.6 % (arm 90.2 %; leg 88.2 %) [p < 0.001]. All patients had improved symptoms and function. Bioimpedance spectroscopy showed reduced but ongoing extracellular fluid, consistent with the underlying lymphatic pathology. Liposuction is a safe and effective option for carefully selected patients with advanced lymphedema. Assessment, treatment, and follow-up by a multidisciplinary team is essential.

The apparent mass and mechanical impedance of the hand and the transmission of vibration to the fingers, hand, and arm

NASA Astrophysics Data System (ADS)

Concettoni, Enrico; Griffin, Michael

2009-08-01

Although hand-transmitted vibration causes injury and disease, most often evident in the fingers, the biodynamic responses of the fingers, hand, and arm are not yet well understood. A method of investigating the motion of the entire finger-hand-arm system, based on the simultaneous measurement of the biodynamic response at the driving point and the transmissibility to many points on the finger-hand-arm system, is illustrated. Fourteen male subjects participated in an experiment in which they pushed down on a vertically vibrating metal plate with their right forearm pronated and their elbow bent at 90°. The apparent mass and mechanical impedance of the finger-hand-arm system were measured for each of seven different contact conditions between the plate and the fingers and hand. Simultaneously, the vibration of the fingers, hand, and arm was measured at 41 locations using a scanning laser Doppler vibrometer. Transmissibilities showed how the vibration was transmitted along the arm and allowed the construction of spectral operating deflection shapes showing the vibration pattern of the fingers, hand, and arm for each of the seven contact conditions. The vibration patterns at critical frequencies for each contact condition have been used to explain features in the driving point biodynamic responses and the vibration behaviour of the hand-arm system. Spectral operating deflection shapes for the upper limb assist the interpretation of driving point biodynamic responses and help to advance understanding required to predict, explain, and control the various effects of hand-transmitted vibration.

Variability in hand-arm vibration during grinding operations.

PubMed

Liljelind, Ingrid; Wahlström, Jens; Nilsson, Leif; Toomingas, Allan; Burström, Lage

2011-04-01

Measurements of exposure to vibrations from hand-held tools are often conducted on a single occasion. However, repeated measurements may be crucial for estimating the actual dose with good precision. In addition, knowledge of determinants of exposure could be used to improve working conditions. The aim of this study was to assess hand-arm vibration (HAV) exposure during different grinding operations, in order to obtain estimates of the variance components and to evaluate the effect of work postures. Ten experienced operators used two compressed air-driven angle grinders of the same make in a simulated work task at a workplace. One part of the study consisted of using a grinder while assuming two different working postures: at a standard work bench (low) and on a wall with arms elevated and the work area adjusted to each operator's height (high). The workers repeated the task three times. In another part of the study, investigating the wheel wear, for each grinder, the operators used two new grinding wheels and with each wheel the operator performed two consecutive 1-min grinding tasks. Both grinding tasks were conducted on weld puddles of mild steel on a piece of mild steel. Measurements were taken according to ISO-standard 5349 [the equivalent hand-arm-weighted acceleration (m s(-2)) averaged over 1 min]. Mixed- and random-effects models were used to investigate the influence of the fixed variables and to estimate variance components. The equivalent hand-arm-weighted acceleration assessed when the task was performed on the bench and at the wall was 3.2 and 3.3 m s(-2), respectively. In the mixed-effects model, work posture was not a significant variable. The variables 'operator' and 'grinder' together explained only 12% of the exposure variability and 'grinding wheel' explained 47%; the residual variability of 41% remained unexplained. When the effect of grinding wheel wear was investigated in the random-effects model, 37% of the variability was associated with

Hand-arm vibration disorder among grass-cutter workers in Malaysia.

PubMed

Azmir, Nor Azali; Ghazali, Mohd Imran; Yahya, Musli Nizam; Ali, Mohamad Hanafi

2016-09-01

Prolonged exposure to hand-transmitted vibration from grass-cutting machines has been associated with increasing occurrences of symptoms and signs of occupational diseases related to hand-arm vibration syndrome (HAVS). A cross-sectional study was carried out using an adopted HAVS questionnaire on hand-arm vibration exposure and symptoms distributed to 168 male workers from the grass and turf maintenance industry who use hand-held grass-cutting machines as part of their work. The prevalence ratio and symptom correlation to HAVS between high and low-moderate exposure risk groups were evaluated. There were positive HAVS symptoms relationships between the low-moderate exposure group and the high exposure group among hand-held grass-cutting workers. The prevalence ratio was considered high because there were indicators that fingers turned white and felt numb, 3.63, 95% CI [1.41, 9.39] and 4.24, 95% CI [2.18, 8.27], respectively. Less than 14.3% of workers stated that they were aware of the occupational hand-arm vibration, and it seemed to be related to the finger blanching and numbness. The results suggest that HAVS is under-diagnosed in Malaysia, especially in the agricultural sectors. More information related to safety and health awareness programmes for HAVS exposure is required among hand-held grass-cutting workers.

Pacing the phasing of leg and arm movements in breaststroke swimming to minimize intra-cyclic velocity fluctuations

PubMed Central

Roerdink, Melvyn; Huibers, Alja V.; Evers, Lotte L. W.; Beek, Peter J.

2017-01-01

In swimming propelling efficiency is partly determined by intra-cyclic velocity fluctuations. The higher these fluctuations are at a given average swimming velocity, the less efficient is the propulsion. This study explored whether the leg-arm coordination (i.e. phase relation ϕ) within the breaststroke cycle can be influenced with acoustic pacing, and whether the so induced changes are accompanied by changes in intra-cyclic velocity fluctuations. Twenty-six participants were asked to couple their propulsive leg and arm movements to a double-tone metronome beat and to keep their average swimming velocity constant over trials. The metronome imposed five different phase relations ϕi (90, 135, 180, 225 and 270°) of leg-arm coordination. Swimmers adjusted their technique under the influence of the metronome, but failed to comply to the velocity requirement for ϕ = 90 and 135°. For imposed ϕ = 180, 225 and 270°, the intra-cyclic velocity fluctuations increased with increasing ϕ, while average swimming velocity did not differ. This suggests that acoustic pacing may be used to adjust ϕ and thereby performance of breaststroke swimming given the dependence of propelling efficiency on ϕ. PMID:29023496

Pacing the phasing of leg and arm movements in breaststroke swimming to minimize intra-cyclic velocity fluctuations.

PubMed

van Houwelingen, Josje; Roerdink, Melvyn; Huibers, Alja V; Evers, Lotte L W; Beek, Peter J

2017-01-01

In swimming propelling efficiency is partly determined by intra-cyclic velocity fluctuations. The higher these fluctuations are at a given average swimming velocity, the less efficient is the propulsion. This study explored whether the leg-arm coordination (i.e. phase relation ϕ) within the breaststroke cycle can be influenced with acoustic pacing, and whether the so induced changes are accompanied by changes in intra-cyclic velocity fluctuations. Twenty-six participants were asked to couple their propulsive leg and arm movements to a double-tone metronome beat and to keep their average swimming velocity constant over trials. The metronome imposed five different phase relations ϕi (90, 135, 180, 225 and 270°) of leg-arm coordination. Swimmers adjusted their technique under the influence of the metronome, but failed to comply to the velocity requirement for ϕ = 90 and 135°. For imposed ϕ = 180, 225 and 270°, the intra-cyclic velocity fluctuations increased with increasing ϕ, while average swimming velocity did not differ. This suggests that acoustic pacing may be used to adjust ϕ and thereby performance of breaststroke swimming given the dependence of propelling efficiency on ϕ.

Association of hand and arm disinfection with asthma control in US nurses.

PubMed

Dumas, Orianne; Varraso, Raphäelle; Boggs, Krislyn M; Descatha, Alexis; Henneberger, Paul K; Quinot, Catherine; Speizer, Frank E; Zock, Jan-Paul; Le Moual, Nicole; Camargo, Carlos A

2018-05-01

To investigate the association between occupational exposure to disinfectants/antiseptics used for hand hygiene and asthma control in nurses. In 2014, we invited female nurses with asthma drawn from the Nurses' Health Study II to complete two supplemental questionnaires on their occupation and asthma (cross-sectional study, response rate: 80%). Among 4055 nurses (mean age: 59 years) with physician-diagnosed asthma and asthma medication use in the past year, we examined asthma control, as defined by the Asthma Control Test (ACT). Nurses were asked about the daily frequency of hand hygiene tasks: 'wash/scrub hands with disinfectants/hand sanitizers' (hand hygiene) and 'wash/scrub arms with disinfecting products' (surrogate of surgical hand/arm antisepsis). Analyses were adjusted for age, race, ethnicity, smoking status and body mass index. Nurses with partly controlled asthma (ACT: 20-24, 50%) and poorly controlled asthma (ACT ≤19, 18%) were compared with nurses with controlled asthma (ACT=25, 32%). In separate models, both hand and arm hygiene were associated with poorly controlled asthma. After mutual adjustment, only arm hygiene was associated with poorly controlled asthma: OR (95% CI) for <1 time/day, 1.38 (1.06 to 1.80); ≥1 time/day, 1.96 (1.52 to 2.51), versus never. We observed a consistent dose-response relationship between frequency of arm hygiene tasks (never to >10 times/day) and poor asthma control. Associations persisted after further adjustment for surfaces/instruments disinfection tasks. Frequency of hand/arm hygiene tasks in nurses was associated with poor asthma control. The results suggest an adverse effect of products used for surgical hand/arm antisepsis. This potential new occupational risk factor for asthma warrants further study. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Evaluation of a functional hand orthosis combined with electrical stimulation adjunct to arm-hand rehabilitation in subacute stroke patients with a severely to moderately affected hand function.

PubMed

Franck, Johan Anton; Smeets, Rob Johannes Elise Marie; Seelen, Henk Alexander Maria

2018-01-09

To investigate the usability and effectiveness of a functional hand orthosis, combined with electrical stimulation adjunct to therapy-as-usual, on functional use of the moderately/severely impaired hand in sub-acute stroke patients. Single case experiment (A-B-A'-design) involving eight sub-acute stroke patients. The functional hand orthosis and electrical stimulation were used for six weeks, four days/week, 45'/day. Action_Research_Arm_Test, Intrinsic_Motivation_Inventory. At group level, patients improved 19.2 points (median value) (interquartile range: [8.8, 29.5] points) on the Action_Research_Arm_Test (p = 0.001). After correcting for spontaneous recovery and/or therapy-as-usual effects Action_Research_Arm_Test scores still improved significantly (median: 17.2 points; interquartile range: [5.1, 29.2] points) (p = 0.002). At individual level, six patients had improved as to arm-hand skill performance at follow-up (p < = 0.010). In one patient, arm-hand skill performance improvement did not attain statistical significance. In another patient, no arm-hand skill performance improvement was observed. Average Intrinsic_Motivation_Inventory sub-scores were between 4.6 and 6.3 (maximum: 7), except for 'perceived pressure/tension' (3.3). Sub-acute stroke patients who display only little/modest improvement on their capacity to perform daily activities, seem to benefit from training with a dynamic arm orthosis in combination with electrical stimulation. Patients' perceived intrinsic motivation and sense of self-regulation was high. Implications for rehabilitation Arm-hand training featuring the dynamic hand orthosis in combination with electrical stimulation shows a shift from no dexterity to dexterity. As to the users' experience regarding the dynamic hand orthosis, patients perceive a high-intrinsic motivation and sense of self-regulation. Combining the orthosis with electrical stimulation creates opportunities for a nonfunctional hand towards task

Hand-arm vibration in orthopaedic surgery: a neglected risk.

PubMed

Mahmood, F; Ferguson, K B; Clarke, J; Hill, K; Macdonald, E B; Macdonald, D J M

2017-12-30

Hand-arm vibration syndrome is an occupational disease caused by exposure to hand-arm transmitted vibration. The Health and Safety Executive has set limits for vibration exposure, including an exposure action value (EAV), where steps should be taken to reduce exposure, and an exposure limit value (ELV), beyond which vibrating equipment must not be used for the rest of the working day. To measure hand-arm transmitted vibration among orthopaedic surgeons, who routinely use hand-operated saws. We undertook a cadaveric study measuring vibration associated with a tibial cut using battery-operated saws. Three surgeons undertook three tibial cuts each on cadaveric tibiae. Measurements were taken using a frequency-weighted root mean square acceleration, with the vibration total value calculated as the root of the sums squared in each of the three axes. A mean (SD) vibration magnitude of 1 (0.2) m/s2 in the X-axis, 10.3 (1.9) m/s2 in the Y-axis and 4.2 (1.3) m/s2 in the Z-axis was observed. The weighted root mean squared magnitude of vibration was 11.3 (1.7) m/s2. These results suggest an EAV of 23 min and ELV of 1 h 33 min using this equipment. Our results demonstrate that use of a battery-operated sagittal saw can transmit levels of hand-arm vibration approaching the EAV or ELV through prolonged use. Further study is necessary to quantify this risk and establish whether surveillance is necessary for orthopaedic surgeons. © The Author 2017. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Validity and inter-observer reliability of subjective hand-arm vibration assessments.

PubMed

Coenen, Pieter; Formanoy, Margriet; Douwes, Marjolein; Bosch, Tim; de Kraker, Heleen

2014-07-01

Exposure to mechanical vibrations at work (e.g., due to handling powered tools) is a potential occupational risk as it may cause upper extremity complaints. However, reliable and valid assessment methods for vibration exposure at work are lacking. Measuring hand-arm vibration objectively is often difficult and expensive, while often used information provided by manufacturers lacks detail. Therefore, a subjective hand-arm vibration assessment method was tested on validity and inter-observer reliability. In an experimental protocol, sixteen tasks handling powered tools were executed by two workers. Hand-arm vibration was assessed subjectively by 16 observers according to the proposed subjective assessment method. As a gold standard reference, hand-arm vibration was measured objectively using a vibration measurement device. Weighted κ's were calculated to assess validity, intra-class-correlation coefficients (ICCs) were calculated to assess inter-observer reliability. Inter-observer reliability of the subjective assessments depicting the agreement among observers can be expressed by an ICC of 0.708 (0.511-0.873). The validity of the subjective assessments as compared to the gold-standard reference can be expressed by a weighted κ of 0.535 (0.285-0.785). Besides, the percentage of exact agreement of the subjective assessment compared to the objective measurement was relatively low (i.e., 52% of all tasks). This study shows that subjectively assessed hand-arm vibrations are fairly reliable among observers and moderately valid. This assessment method is a first attempt to use subjective risk assessments of hand-arm vibration. Although, this assessment method can benefit from some future improvement, it can be of use in future studies and in field-based ergonomic assessments. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Hand function in workers with hand-arm vibration syndrome.

PubMed

Cederlund, R; Isacsson, A; Lundborg, G

1999-01-01

Hand-arm vibration syndrome has been specially addressed in the Scandinavian countries in recent years, but the syndrome is still not sufficiently recognized in many countries. The object of this preliminary study was to describe the nature and character of vibration-induced impairment in the hands of exposed workers. Twenty symptomatic male workers (aged 28 to 65 years) subjected to vibration by hand-held tools were interviewed about subjective symptoms and activities of daily living and were assessed with a battery of objective tests for sensibility, dexterity, grip function, and grip strength. The test results were compared with normative data. The majority of patients complained of cold intolerance, numbness, pain, sensory impairment, and difficulties in handling manual tools and in handwriting. The various objective tests showed considerable variation in indications of pathologic outcome, revealing differences in sensitivity to detect impaired hand function. Semmes-Weinstein monofilament testing for perception of light touch-deep pressure sensation, the small-object shape identification test, and moving two-point discrimination testing for functional sensibility provided the most indications of pathologic outcomes. The authors conclude that vibration-exposed patients present considerable impairment in hand function.

Subjective scaling of hand-arm vibration.

PubMed

Maeda, Setsuo; Shibata, Nobuyuki

2008-04-01

The purpose of this research was to establish a scale for comfort with regard to hand-arm vibration using the category judgment method and to validate the frequency-weighting method of the ISO 5349-1 standard. Experiments were conducted using random signals as stimuli. These stimuli consisted of three types of signal, namely designated stimulus F, with flat power spectrum density (PSD) ranging from 1 to 1,000 Hz, stimulus H with PSD which became 20 dB higher at 1,000 Hz than at 1 Hz, and stimulus L that had a PSD 20 dB lower at 1,000 Hz. These stimuli were selected from the specific spectrum patterns of hand-held vibration tools. These signals were modified by the Wh frequency weighting in accordance with ISO 5349-1, and the R.M.S. values were adjusted to be equal. In addition, the signal levels were varied over a range of five steps to create 15 kinds of individual stimuli. The subjects sat in front of a vibrator and grasped the mounted handle which exposed them to vertical vibrations after which they were asked to choose a numerical category to best indicate their perceived level of comfort (or otherwise) during each stimulus. From the experimental results of the category judgment method, the relationship between the psychological values and the frequency-weighted R.M.S. acceleration according to the ISO 5349-1 standard was obtained. It was found that the subjective response scaling of hand-arm vibration can be used for design-objective values of hand-held tool vibration.

Detection of Hand and Leg Motor Tract Injury Using Novel Diffusion Tensor MRI Tractography in Children with Central Motor Dysfunction

PubMed Central

Jeong, Jeong-Won; Lee, Jessica; Kamson, David O.; Chugani, Harry T.; JuhÁsz, Csaba

2015-01-01

Purpose To examine whether an objective segmenation of corticospinal tract (CST) associated with hand and leg movements can be used to detect central motor weakness in the corresponding extremities in a pediatric population. Material and Methods This retrospective study included diffusion tensor imaging (DTI) of 25 children with central paresis affecting at least one limb (age: 9.0±4.2 years, 15 boys, 5/13/7 children with left/right/both hemispheric lesions including ischemia, cyst, and gliosis), as well as 42 pediatric control subjects with no motor dysfunction (age: 9.0±5.5 years, 21 boys, 31 healthy/11 non-lesional epilepsy children). Leg- and hand-related CST pathways were segmented using DTI-maximum a posteriori (DTI-MAP) classification. The resulting CST volumes were then divided by total supratentorial white matter volume, resulting in a marker called “normalized streamline volume ratio (NSVR)” to quantify the degree of axonal loss in separate CST pathways associated with leg and hand motor functions. A receiver operating characteristic curve was applied to measure the accuracy of this marker to identify extremities with motor weakness. Results NSVR values of hand/leg CST selectively achieved the following values of accuracy/sensitivity/specificity: 0.84/0.84/0.57, 0.82/0.81/0.55, 0.78/0.75/0.55, 0.79/0.81/0.54 at a cut-off of 0.03/0.03/0.03/0.02 for right hand CST, left hand CST, right leg CST, and left leg CST, respectively. Motor weakness of hand and leg was most likely present at the cut-off values of hand and leg NSVR (i.e., 0.029/0.028/0.025/0.020 for left-hand/right-hand/left-leg/right-leg). The control group showed a moderate age-related increase in absolute CST volumes and a biphasic age-related variation of the normalized CST volumes, which were lacking in the paretic children. Conclusions This study demonstrates that DTI-MAP classification may provide a new imaging tool to quantify axonal loss in children with central motor dysfunction

Detection of hand and leg motor tract injury using novel diffusion tensor MRI tractography in children with central motor dysfunction.

PubMed

Jeong, Jeong-Won; Lee, Jessica; Kamson, David O; Chugani, Harry T; Juhász, Csaba

2015-09-01

To examine whether an objective segmenation of corticospinal tract (CST) associated with hand and leg movements can be used to detect central motor weakness in the corresponding extremities in a pediatric population. This retrospective study included diffusion tensor imaging (DTI) of 25 children with central paresis affecting at least one limb (age: 9.0±4.2years, 15 boys, 5/13/7 children with left/right/both hemispheric lesions including ischemia, cyst, and gliosis), as well as 42 pediatric control subjects with no motor dysfunction (age: 9.0±5.5years, 21 boys, 31 healthy/11 non-lesional epilepsy children). Leg- and hand-related CST pathways were segmented using DTI-maximum a posteriori (DTI-MAP) classification. The resulting CST volumes were then divided by total supratentorial white matter volume, resulting in a marker called "normalized streamline volume ratio (NSVR)" to quantify the degree of axonal loss in separate CST pathways associated with leg and hand motor functions. A receiver operating characteristic curve was applied to measure the accuracy of this marker to identify extremities with motor weakness. NSVR values of hand/leg CST selectively achieved the following values of accuracy/sensitivity/specificity: 0.84/0.84/0.57, 0.82/0.81/0.55, 0.78/0.75/0.55, 0.79/0.81/0.54 at a cut-off of 0.03/0.03/0.03/0.02 for right hand CST, left hand CST, right leg CST, and left leg CST, respectively. Motor weakness of hand and leg was most likely present at the cut-off values of hand and leg NSVR (i.e., 0.029/0.028/0.025/0.020 for left-hand/right-hand/left-leg/right-leg). The control group showed a moderate age-related increase in absolute CST volumes and a biphasic age-related variation of the normalized CST volumes, which were lacking in the paretic children. This study demonstrates that DTI-MAP classification may provide a new imaging tool to quantify axonal loss in children with central motor dysfunction. Using this technique, we found that early-life brain

Gas exchange kinetics following concentric-eccentric isokinetic arm and leg exercise.

PubMed

Drescher, U; Mookerjee, S; Steegmanns, A; Knicker, A; Hoffmann, U

2017-06-01

To evaluate the effects of exercise velocity (60, 150, 240deg∙s -1 ) and muscle mass (arm vs leg) on changes in gas exchange and arterio-venous oxygen content difference (avDO 2 ) following high-intensity concentric-eccentric isokinetic exercise. Fourteen subjects (26.9±3.1years) performed a 3×20-repetition isokinetic exercise protocol. Recovery beat-to-beat cardiac output (CO) and breath-by-breath gas exchange were recorded to determine post-exercise half-time (t 1/2 ) for oxygen uptake (V˙O 2 pulm), carbon dioxide output (V˙CO 2 pulm), and ventilation (V˙ E ). Significant differences of the t 1/2 values were identified between 60 and 150deg∙s -1 . Significant differences in the t 1/2 values were observed between V˙O 2 pulm and V˙CO 2 pulm and between V˙CO 2 pulm and V˙ E . The time to attain the first avDO 2 -peak showed significant differences between arm and leg exercise. The present study illustrates, that V˙O 2 pulm kinetics are distorted due to non-linear CO dynamics. Therefore, it has to be taken into account, that V˙O 2 pulm may not be a valuable surrogate for muscular oxygen uptake kinetics in the recovery phases. Copyright © 2017 Elsevier B.V. All rights reserved.

On the Other Hand: Overflow Movements of Infants’ Hands and Legs During Unimanual Object Exploration

PubMed Central

Soska, Kasey C.; Galeon, Margaret A.; Adolph, Karen E.

2011-01-01

Motor overflow is extraneous movement in a limb not involved in a motor action. Typically, overflow is observed in people with neurological impairments and in healthy children and adults during strenuous and attention-demanding tasks. In the current study, we found that young infants produce vast amounts of motor overflow, corroborating claims of symmetry being the default state of the motor system. While manipulating an object with one hand, all 27 of the typically-developing 4.5- to 7.5-month-old infants who we observed displayed overflow movements of the free hand (on 4/5 of unimanual actions). Mirror-image movements of the hands occurred on 1/8 of unimanual actions, and the hands and legs moved in synchrony on 1/3 of unimanual acts. Motor overflow was less frequent when infants were in a sitting posture and when infants watched their acting hand, suggesting that upright posture and visual examination may help to alleviate overflow and break obligatory symmetry in healthy infants. PMID:22487940

Robust Arm and Hand Tracking by Unsupervised Context Learning

PubMed Central

Spruyt, Vincent; Ledda, Alessandro; Philips, Wilfried

2014-01-01

Hand tracking in video is an increasingly popular research field due to the rise of novel human-computer interaction methods. However, robust and real-time hand tracking in unconstrained environments remains a challenging task due to the high number of degrees of freedom and the non-rigid character of the human hand. In this paper, we propose an unsupervised method to automatically learn the context in which a hand is embedded. This context includes the arm and any other object that coherently moves along with the hand. We introduce two novel methods to incorporate this context information into a probabilistic tracking framework, and introduce a simple yet effective solution to estimate the position of the arm. Finally, we show that our method greatly increases robustness against occlusion and cluttered background, without degrading tracking performance if no contextual information is available. The proposed real-time algorithm is shown to outperform the current state-of-the-art by evaluating it on three publicly available video datasets. Furthermore, a novel dataset is created and made publicly available for the research community. PMID:25004155

The study on hand-arm vibration syndrome in China.

PubMed

Lin, Wang; Chunzhi, Zhang; Qiang, Zhang; Kai, Zhang; Xiaoli, Zeng

2005-07-01

To review the main achievement and problems of study on hand-arm vibration syndrome in China. The epidemiological and clinical study indicate that HAVS was reported from almost provinces in China, the prevalence of VWF ranges from 2.5% to 82.8% in the workers with vibrating tool use. The exposure-response relationship between prevalence of VWF and intensity and duration of exposed to hand-transmitted vibration has confirmed. Diagnostic criteria of HAVS has been established and performed by Chinese government in 1985, and it was revised by government as a national standard for occupational health in 2002. The "hygienic standard for hand-transmitted vibration in workplace" as a national standard and the "methods of measurement and assessment for hand-transmitted vibration" as a recommend standard were published by government also. The limited value of exposed to hand-arm vibration was 5.0 m/s2 that is energy equivalent frequency-weighted acceleration for a period of 4 h (ahw(4)). There are some problems in this field of China need to further study in the future.

Immediate Effects of Smoking on Cardiorespiratory Responses During Dynamic Exercise: Arm Vs. Leg Ergometry.

PubMed

Chen, Chien-Liang; Tang, Jing-Shia; Li, Ping-Chia; Chou, Pi-Ling

2015-01-01

This study compared the immediate effects of smoking on cardiorespiratory responses to dynamic arm and leg exercises. This randomized crossover study recruited 14 college students. Each participant underwent two sets of arm-cranking (AC) and leg-cycling (LC) exercise tests. The testing sequences of the control trial (participants refrained from smoking for 8 h before testing) and the experimental trial (participants smoked two cigarettes immediately before testing) were randomly chosen. We observed immediate changes in pulmonary function and heart rate variability after smoking and before the exercise test. The participants then underwent graded exercise tests of their arms and legs until reaching exhaustion. We compared the peak work achieved and time to exhaustion during the exercise tests with various cardiorespiratory indices [i.e., heart rate, oxygen consumption (VO2), minute ventilation (VE)]. The differences between the smoking and control trials were calculated using paired t-tests. For the exercise test periods, VO2, heart rate, and VE values were calculated at every 10% increment of the maximal effort time. The main effects of the time and trial, as well as their trial-by-time (4 × 10) interaction effects on the outcome measures, were investigated using repeated measure ANOVA with trend analysis. 5 min after smoking, the participants exhibited reduced forced vital capacities and forced expiratory volumes in the first second (P < 0.05), in addition to elevated resting heart rates (P < 0.001). The high-frequency, low-frequency, and the total power of the heart rate variability were also reduced (P < 0.05) at rest. For the exercise test periods, smoking reduced the time to exhaustion (P = 0.005) and the ventilatory threshold (P < 0.05) in the LC tests, whereas no significant effects were observed in the AC tests. A trend analysis revealed a significant trial-by-time interaction effect for heart rate, VO2, and VE during the graded exercise test (all P < 0

Mechanical impedance and absorbed power of hand-arm under x(h)-axis vibration and role of hand forces and posture.

PubMed

Aldien, Yasser; Marcotte, Pierre; Rakheja, Subhash; Boileau, Paul-Emile

2005-07-01

The biodynamic responses of the hand-arm system under x(h)-axis vibration are investigated in terms of the driving point mechanical impedance (DPMI) and absorbed power in a laboratory study. For this purpose, seven healthy male subjects are exposed to two levels of random vibration in the 8-1,000 Hz frequency range, using three instrumented cylindrical handles of different diameters (30, 40 and 50 mm), and different combinations of grip (10, 30 and 50 N) and push (0, 25 and 50 N) forces. The experiments involve grasping the handle while adopting two different postures, involving elbow flexion of 90 degrees and 180 degrees, with wrist in the neutral position for both postures. The analyses of the results revealed peak DPMI magnitude and absorbed power responses near 25 Hz and 150 Hz, for majority of the test conditions considered. The frequency corresponding to the peak response increased with increasing hand forces. Unlike the absorbed power, the DPMI response was mostly observed to be insensitive to variations in the excitation magnitude. The handle diameter revealed obvious effects on the DPMI magnitude, specifically at frequencies above 250 Hz, which was not evident in the absorbed power due to relatively low velocity at higher frequencies. The influence of hand forces was also evident on the DPMI magnitude response particularly at frequencies. above 100 Hz, while the effect of hand-arm posture on the DPMI magnitude was nearly negligible. The magnitude of power absorbed within the hand and arm was observed to be strongly dependent upon the excitation level over the entire frequency range, while the influence of hand-arm posture on the total absorbed power was observed to be important. The effect of variations in the hand forces on the absorbed power was relatively small for the bent elbow posture, while an increase in either the grip or the push force coupled with the extended arm posture resulted in considerably higher energy absorption. The results suggested

[Hand fine motor skills and use of both hand and arm in subjects after a stroke: a systematic review].

PubMed

Ostolaza, M; Abudarham, J; Dilascio, S; Drault-Boedo, E; Gallo, S; Garcete, A; Kramer, M; Maiaru, M; Mendelevich, A; Modica, M; Peralta, F; Sanchez-Correa, C

2017-04-01

In clinical practice it is important to be able to assess the function of the upper limb of the patient who has suffered a stroke. There is currently no systemic review that could identify assessment tools for the 'fine use of the hand' and 'use of both hand and arm'. Primary, to identify observational tools which can assess the fine use of the hand and the use of both hand and arm in patients with stroke sequels. Secondary, to analyze the bias risk in the included articles, describing and categorizing the clinical utility, validity and reliability. A search was carried in Medline, LILACS, SciELO and Open Grey, which included articles published until October 2015. Studies that validate assessing tools of the upper limb in subjects with a stroke sequel which evaluate the fine use of the hand and the use of both hand and arm were included. Eleven tools in evaluate observational haven been selected, which assess the fine use of the hand and the use of hand and arm. In every case both validity and reliability have been reported, but clinical utility has been less considered for assessment. The studies that researched these tools showed a high risk of bias in their development. ARAT-19 showed a lower bias risk, but when it has to do with applicability and the reference trial is taken into account, the level of concern is high.

Effect of hand paddles and parachute on butterfly coordination.

PubMed

Telles, Thiago; Barroso, Renato; Barbosa, Augusto Carvalho; Salgueiro, Diego Fortes de Souza; Colantonio, Emilson; Andries Júnior, Orival

2015-01-01

This study investigated the effects of hand paddles, parachute and hand paddles plus parachute on the inter-limb coordination of butterfly swimming. Thirteen male swimmers were evaluated in four random maximal intensity conditions: without equipment, with hand paddles, with parachute and with hand paddles + parachute. Arm and leg stroke phases were identified by 2D video analysis to calculate the total time gap (T1: time between hands' entry in the water and high break-even point of the first undulation; T2: time between the beginning of the hand's backward movement and low break-even point of the first undulation; T3: time between the hand's arrival in a vertical plane to the shoulders and high break-even point of the second undulation; T4: time between the hand's release from the water and low break-even point of the second undulation). The swimming velocity was reduced and T1, T2 and T3 increased in parachute and hand paddles + parachute. No changes were observed in T4. Total time gap decreased in parachute and hand paddles + parachute. It is concluded that hand paddles do not influence the arm-to-leg coordination in butterfly, while parachute and hand paddles + parachute do change it, providing a greater propulsive continuity.

Intra-Cyclic Phases of Arm-Leg Movement and Index of Coordination in Relation to Sprint Breaststroke Swimming in Young Swimmers

PubMed Central

Strzala, Marek; Krezalek, Piotr; Glab, Grzegorz; Kaca, Marcin; Ostrowski, Andrzej; Stanula, Arkadiusz; Tyka, Anna K.

2013-01-01

Despite the limitations set by FINA regulations, execution technique in breaststroke swimming is being improved thanks to more and more advanced analyses of the efficiency of the swimmer’s movements. The aim of this study was to detect the parameters of the time structure of the cycle correlated with the maximal swimming speed at the of 50 meters distance, in order to focus to specific technical aspects in the breaststroke training. In the group of 23 participants, between the age of 15.0 ± 1.17, the breaststroke cycle movement of the arms and legs was divided into two phases: propulsive or non-propulsive. In addition, indices characterizing the temporal coordination of movements of the upper limbs in relation to the lower limbs were distinguished: 1) Arm-Leg Lag - determines the interval between the phases of propulsion generated by upper and lower limbs; 2) Glide or Overlap - the inter-cyclic glide or overlap of the propulsive movement of the upper on lower limbs. Significant dependence was noted between the swim speed (V50surface breast) and the percentage of time of the arm propulsive in-sweep phase 0.64, p < 0.01. A significant correlation was observed between the V50surface breast with the percentage of partially surfaced hand phase of arm recovery 0.54, p < 0.01. Correlation between total leg propulsion and non-propulsion phases with V50surface breast was 0.49 and -0.49 respectively, both p < 0.01. The Glide or Overlap index was significantly related to the swimming speed V50surface breast 0.48, p < 0.05. This type of analysis suggests how to refine the swimming technique, with the goal to improve the current speed capabilities; furthermore the results also indicate the direction of its development in the future swimmers of the group studied. Key Points This study investigated the influence of the inter- and intra-cyclic time structure of the movements in sprint breaststroke swimming. The distinction of the operations phases of the upper limbs in the

Arm and Intensity-Matched Leg Exercise Induce Similar Inflammatory Responses.

PubMed

Leicht, Christof A; Paulson, Thomas A W; Goosey-Tolfrey, Victoria L; Bishop, Nicolette C

2016-06-01

The amount of active muscle mass can influence the acute inflammatory response to exercise, associated with reduced risk for chronic disease. This may affect those restricted to upper body exercise, for example, due to injury or disability. The purpose of this study was to compare the inflammatory responses for arm exercise and intensity-matched leg exercise. Twelve male individuals performed three 45-min constant load exercise trials after determination of peak oxygen uptake for arm exercise (V˙O2peak A) and cycling (V˙O2peak C): 1) arm cranking exercise at 60% V˙O2peak A, 2) moderate cycling at 60% V˙O2peak C, and 3) easy cycling at 60% V˙O2peak A. Cytokine, adrenaline, and flow cytometric analysis of monocyte subsets were performed before and up to 4 h postexercise. Plasma IL-6 increased from resting concentrations in all trials; however, postexercise concentrations were higher for arm exercise (1.73 ± 1.04 pg·mL) and moderate cycling (1.73 ± 0.95 pg·mL) compared with easy cycling (0.87 ± 0.41 pg·mL; P < 0.04). Similarly, the plasma IL-1ra concentration in the recovery period was higher for arm exercise (325 ± 139 pg·mL) and moderate cycling (316 ± 128 pg·mL) when compared with easy cycling (245 ± 77 pg·mL, P < 0.04). Arm exercise and moderate cycling induced larger increases in monocyte numbers and larger increases of the classical monocyte subset in the recovery period than easy cycling (P < 0.05). The postexercise adrenaline concentration was lowest for easy cycling (P = 0.04). Arm exercise and cycling at the same relative exercise intensity induces a comparable acute inflammatory response; however, cycling at the same absolute oxygen uptake as arm exercise results in a blunted cytokine, monocyte, and adrenaline response. Relative exercise intensity appears to be more important to the acute inflammatory response than modality, which is of major relevance for populations restricted to upper body exercise.

[Carpal canal ultrasound examination in patients with mild hand-arm vibration disease].

PubMed

Liu, Y Z; Ye, Z H; Yang, W L; Zhu, J X; Lu, Q J; Su, W L

2016-08-20

Objective: To investigate the clinical value of ultrasound examination of carpal canal structure in patients with mild hand-arm vibration disease. Methods: A total of 29 patients (58 wrists) with mild hand-arm vibration disease who were treated in Shenzhen Prevention and Treatment Center for Occupational Diseases from May to December, 2015 were enrolled as observation group, and 20 healthy volunteers (40 wrists) were enrolled as the control group. Color Doppler ultrasound was used to observe the morphology and echo of the median nerve in the carpal canal and 9 muscle tendons and transverse carpal ligament. The thickness of transverse carpal ligament and diameter of the median nerve at the level of the hamulus of hamate bone were measured, as well as the cross-sectional area of the median nerve at the level of pisiform bone. Results: In the 29 patients with hand-arm vibration disease patients in the observation group, 8 experienced entrapment of the median nerve in the carpal canal, among whom 5 had entrapment in both wrists; there were 13 wrists (23%) with nerve entrapment and 45 wrists (77%) without nerve entrapment. Compared with the control group, the patients with hand-arm vibration disease and nerve entrapment in the observation group showed significant thickening of the transverse carpal ligament at the level of the hamulus of hamate bone and a significant increase in the cross-sectional area of the median nerve at the level of pisiform bone ( P <0.05) , while there were no significant differences in the thickness of transverse carpal ligament at the level of the hamulus of hamate bone and the cross-sectional area of the median nerve at the level of pisiform bone ( t=- 9.397 and -4.385, both P >0.05) . Conclusion: Ultrasound examination can clearly show the radiological changes of carpal canal contents in patients with mild hand-arm vibration disease and has a certain diagnostic value in nerve damage in patients with hand-arm vibration disease.

Hand-arm vibration syndrome: What family physicians should know.

PubMed

Shen, Shixin Cindy; House, Ronald A

2017-03-01

To provide family physicians with an understanding of the epidemiology, pathogenesis, symptoms, diagnosis, and management of hand-arm vibration syndrome (HAVS), an important and common occupational disease in Canada. A MEDLINE search was conducted for research and review articles on HAVS. A Google search was conducted to obtain gray literature relevant to the Canadian context. Additional references were obtained from the articles identified. Hand-arm vibration syndrome is a prevalent occupational disease affecting workers in multiple industries in which vibrating tools are used. However, it is underdiagnosed in Canada. It has 3 components-vascular, in the form of secondary Raynaud phenomenon; sensorineural; and musculoskeletal. Hand-arm vibration syndrome in its more advanced stages contributes to substantial disability and poor quality of life. Its diagnosis requires careful history taking, in particular occupational history, physical examination, laboratory tests to rule out alternative diagnoses, and referral to an occupational medicine specialist for additional investigations. Management involves reduction of vibration exposure, avoidance of cold conditions, smoking cessation, and medication. To ensure timely diagnosis of HAVS and improve prognosis and quality of life, family physicians should be aware of this common occupational disease and be able to elicit the relevant occupational history, refer patients to occupational medicine clinics, and appropriately initiate compensation claims. Copyright© the College of Family Physicians of Canada.

Reanimating the arm and hand with intraspinal microstimulation

NASA Astrophysics Data System (ADS)

Zimmermann, Jonas B.; Seki, Kazuhiko; Jackson, Andrew

2011-10-01

To date, there is no effective therapy for spinal cord injury, and many patients could benefit dramatically from at least partial restoration of arm and hand function. Despite a substantial body of research investigating intraspinal microstimulation (ISMS) in frogs, rodents and cats, little is known about upper-limb responses to cervical stimulation in the primate. Here, we show for the first time that long trains of ISMS delivered to the macaque spinal cord can evoke functional arm and hand movements. Complex movements involving coordinated activation of multiple muscles could be elicited from a single electrode, while just two electrodes were required for independent control of reaching and grasping. We found that the motor responses to ISMS were described by a dual exponential model that depended only on stimulation history. We demonstrate that this model can be inverted to generate stimulus trains capable of eliciting arbitrary, graded motor responses, and could be used to restore volitional movements in a closed-loop brain-machine interface.

The relationships between hand coupling force and vibration biodynamic responses of the hand-arm system.

PubMed

Pan, Daniel; Xu, Xueyan S; Welcome, Daniel E; McDowell, Thomas W; Warren, Christopher; Wu, John; Dong, Ren G

2018-06-01

This study conducted two series of experiments to investigate the relationships between hand coupling force and biodynamic responses of the hand-arm system. In the first experiment, the vibration transmissibility on the system was measured as a continuous function of grip force while the hand was subjected to discrete sinusoidal excitations. In the second experiment, the biodynamic responses of the system subjected to a broadband random vibration were measured under five levels of grip forces and a combination of grip and push forces. This study found that the transmissibility at each given frequency increased with the increase in the grip force before reaching a maximum level. The transmissibility then tended to plateau or decrease when the grip force was further increased. This threshold force increased with an increase in the vibration frequency. These relationships remained the same for both types of vibrations. The implications of the experimental results are discussed. Practitioner Summary: Shocks and vibrations transmitted to the hand-arm system may cause injuries and disorders of the system. How to take hand coupling force into account in the risk assessment of vibration exposure remains an important issue for further studies. This study is designed and conducted to help resolve this issue.

[Hand-arm vibration syndrome in a nurse carrying out gypsum cutting operations].

PubMed

Speziale, Martina; Picchiotti, E

2009-01-01

A professional nurse, employed mainly on gypsum cutting operations, developed a hand-arm vibration syndrome with Raynaud's phenomenon, neurosensitive disorders and impairment of the bone and joints apparatus of the hand and arm. The nurse underwent diagnostic investigations (cold test, X-ray of the upper limbs, blood tests); also the vibration levels transmitted from instrument were measured and the exposure times were established. Clinical investigations showed the presence of a hand-arm vibration syndrome with secondary Raynaud's phenomenon and environmental surveys revealed very high vibration levels, such as could be associated with the disease with a causal relationship. In the literature no reports exist of the vibration syndrome being associated with health care workers in orthopaedic departments. The case described in this study occurred because of peculiar organisational factors that most likely have never occurred in other hospitals or orthopaedic departments.

Vibrations transmitted from human hands to upper arm, shoulder, back, neck, and head.

PubMed

Xu, Xueyan S; Dong, Ren G; Welcome, Daniel E; Warren, Christopher; McDowell, Thomas W; Wu, John Z

2017-12-01

Some powered hand tools can generate significant vibration at frequencies below 25 Hz. It is not clear whether such vibration can be effectively transmitted to the upper arm, shoulder, neck, and head and cause adverse effects in these substructures. The objective of this study is to investigate the vibration transmission from the human hands to these substructures. Eight human subjects participated in the experiment, which was conducted on a 1-D vibration test system. Unlike many vibration transmission studies, both the right and left hand-arm systems were simultaneously exposed to the vibration to simulate a working posture in the experiment. A laser vibrometer and three accelerometers were used to measure the vibration transmitted to the substructures. The apparent mass at the palm of each hand was also measured to help in understanding the transmitted vibration and biodynamic response. This study found that the upper arm resonance frequency was 7-12 Hz, the shoulder resonance was 7-9 Hz, and the back and neck resonances were 6-7 Hz. The responses were affected by the hand-arm posture, applied hand force, and vibration magnitude. The transmissibility measured on the upper arm had a trend similar to that of the apparent mass measured at the palm in their major resonant frequency ranges. The implications of the results are discussed. Musculoskeletal disorders (MSDs) of the shoulder and neck are important issues among many workers. Many of these workers use heavy-duty powered hand tools. The combined mechanical loads and vibration exposures are among the major factors contributing to the development of MSDs. The vibration characteristics of the body segments examined in this study can be used to help understand MSDs and to help develop more effective intervention methods.

Vibrations transmitted from human hands to upper arm, shoulder, back, neck, and head

PubMed Central

Xu, Xueyan S.; Dong, Ren G.; Welcome, Daniel E.; Warren, Christopher; McDowell, Thomas W.; Wu, John Z.

2016-01-01

Some powered hand tools can generate significant vibration at frequencies below 25 Hz. It is not clear whether such vibration can be effectively transmitted to the upper arm, shoulder, neck, and head and cause adverse effects in these substructures. The objective of this study is to investigate the vibration transmission from the human hands to these substructures. Eight human subjects participated in the experiment, which was conducted on a 1-D vibration test system. Unlike many vibration transmission studies, both the right and left hand-arm systems were simultaneously exposed to the vibration to simulate a working posture in the experiment. A laser vibrometer and three accelerometers were used to measure the vibration transmitted to the substructures. The apparent mass at the palm of each hand was also measured to help in understanding the transmitted vibration and biodynamic response. This study found that the upper arm resonance frequency was 7–12 Hz, the shoulder resonance was 7–9 Hz, and the back and neck resonances were 6–7 Hz. The responses were affected by the hand-arm posture, applied hand force, and vibration magnitude. The transmissibility measured on the upper arm had a trend similar to that of the apparent mass measured at the palm in their major resonant frequency ranges. The implications of the results are discussed. Relevance to industry Musculoskeletal disorders (MSDs) of the shoulder and neck are important issues among many workers. Many of these workers use heavy-duty powered hand tools. The combined mechanical loads and vibration exposures are among the major factors contributing to the development of MSDs. The vibration characteristics of the body segments examined in this study can be used to help understand MSDs and to help develop more effective intervention methods. PMID:29123326

Hand Gesture Based Wireless Robotic Arm Control for Agricultural Applications

NASA Astrophysics Data System (ADS)

Kannan Megalingam, Rajesh; Bandhyopadhyay, Shiva; Vamsy Vivek, Gedela; Juned Rahi, Muhammad

2017-08-01

One of the major challenges in agriculture is harvesting. It is very hard and sometimes even unsafe for workers to go to each plant and pluck fruits. Robotic systems are increasingly combined with new technologies to automate or semi automate labour intensive work, such as e.g. grape harvesting. In this work we propose a semi-automatic method for aid in harvesting fruits and hence increase productivity per man hour. A robotic arm fixed to a rover roams in the in orchard and the user can control it remotely using the hand glove fixed with various sensors. These sensors can position the robotic arm remotely to harvest the fruits. In this paper we discuss the design of hand glove fixed with various sensors, design of 4 DoF robotic arm and the wireless control interface. In addition the setup of the system and the testing and evaluation under lab conditions are also presented in this paper.

The 'Arm Force Field' method to predict manual arm strength based on only hand location and force direction.

PubMed

La Delfa, Nicholas J; Potvin, Jim R

2017-03-01

This paper describes the development of a novel method (termed the 'Arm Force Field' or 'AFF') to predict manual arm strength (MAS) for a wide range of body orientations, hand locations and any force direction. This method used an artificial neural network (ANN) to predict the effects of hand location and force direction on MAS, and included a method to estimate the contribution of the arm's weight to the predicted strength. The AFF method predicted the MAS values very well (r 2  = 0.97, RMSD = 5.2 N, n = 456) and maintained good generalizability with external test data (r 2  = 0.842, RMSD = 13.1 N, n = 80). The AFF can be readily integrated within any DHM ergonomics software, and appears to be a more robust, reliable and valid method of estimating the strength capabilities of the arm, when compared to current approaches. Copyright © 2016 Elsevier Ltd. All rights reserved.

Assessment of coarse and fine hand motor performance in asymptomatic subjects exposed to hand-arm vibration.

PubMed

Popević, Martin B; Janković, Srđan M; Borjanović, Srđan S; Jovičić, Slavica R; Tenjović, Lazar R; Milovanović, Aleksandar P S; Bulat, Petar

2014-03-01

A frequently encountered exposure profile for hand-arm vibration in contemporary occupational setting comprises workers with a long history of intermittent exposure but without detectable signs of hand-arm vibration syndrome (HAVS). Yet, most of the published studies deal with developed HAVS cases, rarely discussing the biological processes that may be involved in degradation of manual dexterity and grip strength when it can be most beneficial - during the asymptomatic stage. In the present paper, a group of 31 male asymptomatic vibration-exposed workers (according to the Stockholm Workshop Scale) were compared against 30 male controls. They were tested using dynamometry and dexterimetry (modelling coarse and fine manual performance respectively) and cold provocation was done to detect possible differences in manual performance drop on these tests. The results showed reduced manual dexterity but no significant degradation in hand grip strength in the exposed subjects. This suggests that intermittent exposure profile and small cumulative vibration dose could only lead to a measurable deficit in manual dexterity but not hand grip strength even at non-negligible A(8) levels and long term exposures.

Predicting hand function in older adults: evaluations of grip strength, arm curl strength, and manual dexterity.

PubMed

Liu, Chiung-Ju; Marie, Deana; Fredrick, Aaron; Bertram, Jessica; Utley, Kristen; Fess, Elaine Ewing

2017-08-01

Hand function is critical for independence in activities of daily living for older adults. The purpose of this study was to examine how grip strength, arm curl strength, and manual dexterous coordination contributed to time-based versus self-report assessment of hand function in community-dwelling older adults. Adults aged ≥60 years without low vision or neurological disorders were recruited. Purdue Pegboard Test, Jamar hand dynamometer, 30-second arm curl test, Jebsen-Taylor Hand Function Test, and the Late-Life Function and Disability Instrument were administered to assess manual dexterous coordination, grip strength, arm curl strength, time-based hand function, and self-report of hand function, respectively. Eighty-four adults (mean age = 72 years) completed the study. Hierarchical multiple regressions show that older adults with better arm curl strength (β = -.25, p < .01) and manual dexterous coordination (β = -.52, p < .01) performed better on the time-based hand function test. In comparison, older adults with better grip strength (β = .40, p < .01), arm curl strength (β = .23, p < .05), and manual dexterous coordination (β = .23, p < .05) were associated with better self-report of upper extremity function. The relationship between grip strength and hand function may be test-specific. Grip strength becomes a significant factor when the test requires grip strength to successfully complete the test tasks. Arm curl strength independently contributed to hand function in both time-based and self-report assessments, indicating that strength of extrinsic muscles of the hand are essential for hand function.

The effects of mirror therapy on arm and hand function in subacute stroke in patients.

PubMed

Radajewska, Alina; Opara, Józef A; Kucio, Cezary; Błaszczyszyn, Monika; Mehlich, Krzysztof; Szczygiel, Jarosław

2013-09-01

The aim of this study was to evaluate the effect of mirror therapy on arm and hand function in subacute stroke in patients. The study included 60 hemiparetic right-handed patients after ischemic stroke 8-10 weeks after onset. They underwent stationary comprehensive rehabilitation in the rehabilitation centre. They were divided into two randomly assigned groups: mirror (n=30) and control (n=30). For both groups, two subgroups were created: one that included patients with right arm paresis (n=15) and the other that included patients with left arm paresis (n=15). The mirror group received an additional intervention: training with a mirror for 5 days/week, 2 sessions/day, for 21 days. Each single session lasted for 15 min. The control group (n=30) underwent a conventional rehabilitation program without mirror therapy. To evaluate self-care in performing activities of daily living, the Functional Index 'Repty' was used. To evaluate hand and arm function, the Frenchay Arm Test and the Motor Status Score were used. Measurements were performed twice: before and after 21 days of applied rehabilitation. No significant improvement in hand and arm function in both subgroups in Frenchay Arm Test and Motor Status Score scales was observed. However, there was a significant improvement in self-care of activities of daily living in the right arm paresis subgroup in the mirror group measured using the Functional Index 'Repty'. Mirror therapy improves self-care of activities of daily living for patients with right arm paresis after stroke.

Wearable Pulse Oximetry Measurements on the Torso, Arms, and Legs: A Proof of Concept.

PubMed

Kramer, Marcus; Lobbestael, Aaron; Barten, Emily; Eian, John; Rausch, Gregory

2017-03-01

For decades pulse oximeters designed for use on the head, hands, or feet have provided invaluable estimates of oxygen saturation to medical personal attending to combat casualties. However, traditional placement sites are not ideal for the relatively new paradigm of continuous battlefield telemonitoring. To assess the feasibility of oximetry on nontraditional body sites, 42 healthy volunteers were enrolled, consented, and underwent an industry standard induced-hypoxia study. During the study volunteers used prototype wearable oximeters, designed for the torso, arms, and legs. Subsets (size n) of the volunteers had the wearables placed at the following body sites, and achieved accuracies (A RMS , root-mean-square difference) of the following: calf 1.7% (n = 26); bicep 3.1% (n = 12); forearm 3.4% (n = 11); pectoral 2.9% (n = 42); sternum 2.9% (n = 13). In keeping with regulatory guidance calibrations with an A RMS of less than 3.5% are acceptable for potential future development. Additionally, a new method was developed to enable accurate reporting of respiration rate from the pectoral oximeter, A RMS of 1.1 breaths per minute (n = 10). This study demonstrates the feasibility of monitoring oxygen saturation and respiration rate from nontraditional sites via a wearable pulse oximeter. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

Arm mechanical efficiency and arm exercise capacity are relatively preserved in chronic obstructive pulmonary disease.

PubMed

Franssen, Frits M E; Wouters, Emiel F M; Baarends, Erica M; Akkermans, Marco A; Schols, Annemie M W J

2002-10-01

Previous studies indicate that energy expenditure related to physical activity is enhanced and that mechanical efficiency of leg exercise is reduced in patients with chronic obstructive pulmonary disease (COPD). However, it is yet unclear whether an inefficient energy expenditure is also present during other activities in COPD. This study was carried out to examine arm efficiency and peak arm exercise performance relative to leg exercise in 33 (23 male) patients with COPD ((mean +/- SEM) age: 61 +/- 2 yr; FEV : 40 +/- 2% of predicted) and 20 sex- and age-matched healthy controls. Body composition, pulmonary function, resting energy expenditure (REE), and peak leg and arm exercise performance were determined. To calculate mechanical efficiency, subjects performed submaximal leg and arm ergometry at 50% of achieved peak loads. During exercise testing, metabolic and ventilatory parameters were measured. In contrast to a reduced leg mechanical efficiency in patients compared with controls (15.6 +/- 0.6% and 22.5 +/- 0.6%, respectively; < 0.001), arm mechanical efficiency was comparable in both groups (COPD: 18.3 +/- 0.9%, controls: 21.0 +/- 1.2%; NS). Arm efficiency was not related to leg efficiency, pulmonary function, work of breathing, or REE. Also, arm exercise capacity was relatively preserved in patients with COPD (ratio arm peak work rate/leg peak work rate in patients: 89% vs 53% in controls; < 0.001). Mechanical efficiency and exercise capacity of the upper and lower limbs are not homogeneously affected in COPD, with a relative preservation of the upper limbs. This may have implications for screening of exercise tolerance and prescription of training interventions in patients with COPD. Future studies need to elucidate the mechanism behind this observation.

Acute effects of vibration from a chipping hammer and a grinder on the hand-arm system.

PubMed Central

Kihlberg, S; Attebrant, M; Gemne, G; Kjellberg, A

1995-01-01

OBJECTIVES--The purpose of this study was to compare various effects on the hand-arm system of vibration exposure from a chipping hammer and a grinder with the same frequency weighted acceleration. Grip and push forces were measured and monitored during the exposure. The various effects were: muscle activity (measured with surface electrodes), discomfort ratings for different parts of the hand-arm system (made during and after exposure), and vibration perception threshold (for 10 minutes before and 10 minutes after the exposure). RESULTS--No increase in muscle activity due to exposure to vibration was found in the hand muscle studied. In the forearm, conversely, there was an increase in both muscle studied. For the upper arm the muscle activity only increased when exposed to impact vibration. Subjective ratings in the hand and shift in vibration perception threshold were effected more by the grinder than the hammer exposure. CONCLUSION--These results show that the reaction of the hand-arm system to vibration varies with frequency quantitatively as well as qualitatively. They do not support the notion that one single frequency weighted curve would be valid for the different health effects of hand-arm vibration (vascular, musculoskeletal, neurological, and psychophysiological). PMID:8535492

Frequency weightings based on biodynamics of fingers-hand-arm system.

PubMed

Dong, Ren G; Welcome, Daniel E; Wu, John Z

2005-07-01

The frequency weighting for assessing hand-transmitted vibration exposure is critical to obtaining a true dose-response relationship. Any valid weighting must have a solid theoretical foundation. The objectives of this study are to examine the biodynamic foundation for assessing the vibration exposure and to develop a set of biodynamic methods to formulate the frequency weightings for different anatomical locations of the fingers-hand-arm system. The vibration transmissibility measured on the fingers, hand, wrist, elbow, shoulder, and head was used to define the transmitted acceleration-based (TAB) frequency weighting. The apparent masses measured at the fingers and the palm of the hand were used to construct the biodynamic force-based (BFB) weightings. These weightings were compared with the ISO weighting specified in ISO 5349-1 (2001). The results of this study suggest that the frequency weightings for the vibration-induced problems at different anatomical locations of the hand-arm system can be basically divided into three groups: (a) the weighting for the fingers and hand, (b) the weighting for the wrist, elbow, and shoulder, and (c) the weighting for the head. The ISO weighting is highly correlated with the weighting for the second group but not with the first and third groups. The TAB and BFB finger weightings are quite different at frequencies lower than 100 Hz, but they show similar trends at higher frequencies. Both TAB and BFB finger weightings at frequencies higher than 20 Hz are greater than the ISO weighting.

Hand and body radiation exposure with the use of mini C-arm fluoroscopy.

PubMed

Tuohy, Christopher J; Weikert, Douglas R; Watson, Jeffry T; Lee, Donald H

2011-04-01

To determine whole body and hand radiation exposure to the hand surgeon wearing a lead apron during routine intraoperative use of the mini C-arm fluoroscope. Four surgeons (3 hand attending surgeons and 1 hand fellow) monitored their radiation exposure for a total of 200 consecutive cases (50 cases per surgeon) requiring mini C-arm fluoroscopy. Each surgeon measured radiation exposure with a badge dosimeter placed on the outside breast pocket of the lead apron (external whole body exposure), a second badge dosimeter under the lead apron (shielded whole body exposure), and a ring dosimeter (hand exposure). Completed records were noted in 198 cases, with an average fluoroscopy time of 133.52 seconds and average cumulative dose of 19,260 rem-cm(2) per case. The total measured radiation exposures for the (1) external whole body exposure dosimeters were 16 mrem (for shallow depth), 7 mrem (for eye depth), and less than 1 mrem (for deep depth); (2) shielded whole body badge dosimeters recorded less than 1 mrem; and (3) ring dosimeters totaled 170 mrem. The total radial exposure for 4 ring dosimeters that had registered a threshold of 30 mrem or more of radiation exposure was 170 mrem at the skin level, for an average of 42.5 mrem per dosimeter ring or 6.3 mrem per case. This study of whole body and hand radiation exposure from the mini C-arm includes the largest number of surgical cases in the published literature. The measured whole body and hand radiation exposure received by the hand surgeon from the mini C-arm represents a minimal risk of radiation, based on the current National Council on Radiation Protection and Management standards of annual dose limits (5,000 mrem per year for whole body and 50,000 mrem per year to the extremities). Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Exercise capacity in young adults with hypertension and systolic blood pressure difference between right arm and leg after repair of coarctation of the aorta.

PubMed

Instebø, Arne; Norgård, Gunnar; Helgheim, Vegard; Røksund, Ola Drange; Segadal, Leidulf; Greve, Gottfried

2004-10-01

Coarctation of the aorta represents 5-7% of congenital heart defects. Symptoms and prognosis depend on the degree of stenosis, age at surgery, surgical method and the presence of other heart defects. Postoperative complications are hypertension, restenosis and an abnormal blood pressure response during exercise. This study includes 41 patients, 15-40 years old, operated in the period 1975-1996. All were exercised on a treadmill until maximal oxygen consumption was achieved. Blood pressure was measured in the right arm and leg before and immediately after exercise, and in the right arm during exercise. Oxygen consumption was monitored and we defined an aerobic phase, an isocapnic buffering phase and a hypocapnic hyperventilation phase. The resting systolic blood pressure correlates with the resting systolic blood pressure difference between right arm and leg. A resting systolic blood pressure difference between the right arm and leg of 0.13 kPa (1 mmHg) to 2.67 kPa (20 mmHg) corresponds with a slight increase in resting systolic blood pressure. This rise in blood pressure increases the aerobic phase of the exercise test, helping the patients to achieve higher maximal oxygen consumption. A resting systolic blood pressure difference of more than 2.67 kPa (20 mmHg) corresponds with severe hypertension and causes reduction in the aerobic phase and maximal oxygen consumption. Resting systolic blood pressure and resting systolic blood pressure difference between the right arm and leg are not indicators for blood pressure response during exercise. Exercise testing is important to reveal exercise-induced hypertension and to monitor changes in transition from aerobic to anaerobic exercise and limitation to exercise capacity.

A low arm and leg muscle mass to total body weight ratio is associated with an increased prevalence of metabolic syndrome: The Korea National Health and Nutrition Examination Survey 2010-2011.

PubMed

Kim, Yong Hwan; So, Wi-Young

2016-09-14

The aim of this study was to investigate the association between metabolic syndrome (MetS) and arm and leg muscle mass to total weight ratios in Korean adults. This was a randomized, controlled, cross-sectional study. Data from 2,383 adults (1,030 men and 1,353 women) were collected from the Korea National Health and Nutrition Examination Survey 2010-2011. Blood lipid profiles, blood pressure, and anthropometric characteristics, including weight, height, waist circumference, and muscle mass on dual energy X-ray absorptiometry (DXA), were evaluated in the participants. MetS was defined according to the criteria of the National Cholesterol Education Program Adult Treatment Panel III. The average mass of both arms and legs was determined using regional muscle analysis by DXA. Afterwards, the arm and leg muscle mass to total body weight ratio was determined and classified into 4 quartiles (i.e., quartile 1 [highest muscle ratio] to quartile 4 [lowest muscle ratio]). According to the arm muscle and leg muscle ratios, there was a higher prevalence of MetS in quartile 4 than in quartile 1 in both men and women. A low arm and leg muscle mass to body weight ratio was associated with a higher prevalence of MetS after adjusting for age, physical activity, frequency of smoking, and frequency of alcohol consumption. In conclusion, MetS patients demonstrated a lower arm and leg muscle mass to body weight ratio. Strength training for the lower and upper extremities is recommended because it can have a positive effect on MetS prevention.

Vibration energy absorption (VEA) in human fingers-hand-arm system.

PubMed

Dong, R G; Schopper, A W; McDowell, T W; Welcome, D E; Wu, J Z; Smutz, W P; Warren, C; Rakheja, S

2004-07-01

A methodology for measuring the vibration energy absorbed into the fingers and the palm exposed to vibration is proposed to study the distribution of the vibration energy absorption (VEA) in the fingers-hand-arm system and to explore its potential association with vibration-induced white finger (VWF). The study involved 12 adult male subjects, constant-velocity sinusoidal excitations at 10 different discrete frequencies in the range of 16-1000 Hz, and four different hand-handle coupling conditions (finger pull-only, hand grip-only, palm push-only, and combined grip and push). The results of the study suggest that the VEA into the fingers is considerably less than that into the palm at low frequencies (< or = 25 Hz). They are, however, comparable under the excitations in the 250-1000 Hz frequency range. The finger VEA at high frequencies (> or = 100 Hz) is practically independent of the hand-handle coupling condition. The coupling conditions affect the VEA into the fingers and the palm very differently. The finger VEA results suggest that the ISO standardized frequency weighting (ISO 5349-1, 2001) may underestimate the effect of high frequency vibration on vibration-induced finger disorders. The proposed method may provide new opportunities to examine VEA and its association with VWF and other types of vibration-induced disorders in the hand-arm system.

Hand-arm vibration syndrome: A rarely seen diagnosis.

PubMed

Campbell, Rebecca A; Janko, Matthew R; Hacker, Robert I

2017-06-01

Hand-arm vibration syndrome (HAVS) is a collection of sensory, vascular, and musculoskeletal symptoms caused by repetitive trauma from vibration. This case report demonstrates how to diagnose HAVS on the basis of history, physical examination, and vascular imaging and its treatment options. A 41-year-old man who regularly used vibrating tools presented with nonhealing wounds on his right thumb and third digit. Arteriography revealed occlusions of multiple arteries in his hand with formation of collaterals. We diagnosed HAVS, and his wounds healed after several weeks with appropriate treatment. HAVS is a debilitating condition with often irreversible vascular damage, requiring early diagnosis and treatment.

Three-dimensional moment arms and architecture of chimpanzee (Pan troglodytes) leg musculature

PubMed Central

Holowka, Nicholas B; O'Neill, Matthew C

2013-01-01

The muscular and skeletal morphology of the chimpanzee ankle and foot differs from that of humans in many important respects. However, little information is available on the moment arms and architecture of the muscles that function around chimpanzee ankle and foot joints. The main goals of this study were to determine the influence of changes in leg and foot position on the moment arms of these muscle–tendon units (MTUs), and provide new measurements of their architecture. Three-dimensional moment arm data were collected from two adult, cadaveric Pan troglodytes specimens for 11 MTUs that cross the ankle and foot joints. Tendon-excursion measurements were made throughout the full range of plantarflexion–dorsiflexion (PF–DF) and eversion–inversion (EV–IN), including repeated measurements for mm. gastrocnemius at 0 °, 45 °, 90 ° and 135 ° of knee flexion. The total range of motion was calculated from three-dimensional joint motion data while ensuring that foot movement was restricted to a single plane. Measurements of muscle mass, fascicle length, pennation angle and physiological cross-sectional area were then collected for each MTU. Our results demonstrate that joint position has a significant effect on moment arm lengths, and that in some cases this effect is counterintuitive. These new data contribute to filling a significant gap in previously published chimpanzee moment arm data, providing a comprehensive characterization of the MTUs that move the chimpanzee ankle and foot joints. They also provide empirical support to the notion that chimpanzees have larger ranges of motion at these joints than humans. Comparison of osteometric estimates of moment arm lengths to direct tendon-excursion measures provides some guidance for the use of skeletal features in estimations of PF–DF moment arms. Finally, muscle architecture data are consistent with the findings of previous studies, and increase the sample size of the chimpanzee data that are currently

Metabolic Cost of Stride Rate, Resistance, and Combined Use of Arms and Legs on the Elliptical Trainer

ERIC Educational Resources Information Center

Mier, Constance M.; Feito, Yuri

2006-01-01

We measured the effects of stride rate, resistance, and combined arm-leg use on energy expenditure during elliptical trainer exercise and assessed the accuracy of the manufacturer's energy expenditure calculations. Twenty-six men and women (M age = 29 years, SD = 8; M body weight = 73.0 kg, SD = 15.2) participated. Twenty-two participants…

Experiences and consequences for women with hand-arm vibration injuries.

PubMed

Bylund, Sonya Hörnqwist; Ahlgren, Christina

2010-01-01

Vibrating machines are used in a variety of occupations. Exposure to hand-arm vibration can cause vascular, neurological, and muscular symptoms in the hands and arms. This qualitative study provides a deeper understanding of the consequences of vibration injuries in women. In depth interviews were conducted with eight women with vibration injuries. The women were metal and wood product assemblers and dental personnel. The transcribed interviews were analyzed in accordance with the grounded theory method. The core category in the findings was "another life". This was constructed by the categories "consequences for everyday activities", "work performance", "household duties", "leisure", and "self perception" and shows that the injury had affected most parts of the women's lives and decreased their quality of life. The importance of well-functioning hands in all activities was highlighted. Reduced hand function due to numbness, muscle weakness, and pain caused restricted abilities to perform activities at work, at home, and during leisure time. The women described impact on their self-perception, as the injury had affected them in their roles as a worker, mother, and woman. The findings indicate that a vibration injury is a multidimensional problem that can affect every aspect of an individual's life. Health care providers should be aware of these complex consequences.

Space robotics--DLR's telerobotic concepts, lightweight arms and articulated hands.

PubMed

Hirzinger, G; Brunner, B; Landzettel, K; Sporer, N; Butterfass, J; Schedl, M

2003-01-01

The paper briefly outlines DLR's experience with real space robot missions (ROTEX and ETS VII). It then discusses forthcoming projects, e.g., free-flying systems in low or geostationary orbit and robot systems around the space station ISS, where the telerobotic system MARCO might represent a common baseline. Finally it describes our efforts in developing a new generation of "mechatronic" ultra-light weight arms with multifingered hands. The third arm generation is operable now (approaching present-day technical limits). In a similar way DLR's four-fingered hand II was a big step towards higher reliability and yet better performance. Artificial robonauts for space are a central goal now for the Europeans as well as for NASA, and the first verification tests of DLR's joint components are supposed to fly already end of 93 on the space station.

Blood pressure differences between arms and association of dominant hands with blood pressure differences and carotid atherosclerosis.

PubMed

Maeda, Shinji

2013-06-01

Guidelines for the management of hypertension recommend that blood pressure (BP) should be measured twice at every visit; it should be measured in both arms at the first visit, and the right arm BP or higher BP should be recorded. Manufacturers of home BP monitors tend to design the device for measurement of left arm BP. The arm preferred for BP measurement differs according to the methods recommended by the society and according to the home BP monitors. The BP difference (ΔBP) is calculated by subtracting left arm BP from right arm BP. Here, we aim to first investigate which hand will give the most accurate reading by a sphygmomanometer in daily medical practice. Second, we wish to assess the association of the dominant hand with absolute BP difference (|ΔBP|) of at least 10 mmHg and with early atherosclerotic markers in a subanalysis. We found that 6.4% of outpatients were left handed, and the percentage of individuals with systolic |ΔBP| (|ΔSBP|) and diastolic |ΔBP| (|ΔDBP|) of at least 10 mmHg was 14.4 and 7.2%, respectively. The dominant hand was not significantly associated with |ΔBP| of at least 10 mmHg or early atherosclerotic markers. This study suggests that BP measured in one arm is substitutable with that of the other arm because of a lack of association of |ΔBP| with the dominant hand. However, BP of both arms should be actively measured in new outpatients with moderate fever, lifestyle-related diseases, vascular events, age 65 years and above, and smoking history, all of which are factors potentially associated with |ΔBP| of at least 10 mmHg, regardless of the dominant hand.

Recent advances in biodynamics of human hand-arm system.

PubMed

Dong, Ren G; Wu, John Z; Welcome, Daniel E

2005-07-01

The biodynamics of human hand-arm system is one of the most important foundations for the measurement, evaluation, and risk assessment of hand-transmitted vibration (HTV) exposure. This paper presents a new conceptual model relating factors influencing cause-effect relationships for HTV exposure, a new study strategy, and a comprehensive review of the recent advances in the biodynamics closely associated with HTV exposure. The review covers the following five aspects: theoretical modeling of biodynamic responses, vibration transmissibility, driving-point biodynamic responses, evaluation of anti-vibration gloves, and applied forces. This review finds that some significant advances in each of these aspects have been achieved in the recent years. Several important issues and problems in the biodynamic measurement have been identified and resolved, which has significantly helped improve the reliability and accuracy of the experimental data. The results reported in recent years suggest that, from the point of view of biodynamics, the frequency weighting specified in ISO 5349-1 (2001) overestimates the low frequency effect but underestimates the high frequency effect on the fingers and hand. The major problems, issues, and topics for further studies are also outlined in this paper. It is anticipated that the further studies of the biodynamics of the system will eventually lead to establishment of a robust vibration exposure theory. Although this review focuses on the biodynamics of the hand-arm system, the fundamental concepts and some methodologies reviewed in this paper may also be applicable for the study of whole-body vibration exposure.

An improved biomechanical model for simulating the strain of the hand-arm system under vibration stress.

PubMed

Fritz, M

1991-01-01

In order to define relationships between the vibration stress and the strain of the human hand-arm system a biomechanical model was developed. The four masses of the model representing the hand, the forearm and the upper arm were connected by dampers and springs in two perpendicular directions. Simulating muscle activity, damped torsion springs were included additionally. The motions of the model were described by a differential matrix equation which was solved by using a 'transfer matrix routine' as well as by numerical integration. Thus, functions with harmonic or transient time courses could be selected as an excitation. The simulated vibrations were compared with those of other hand-arm models. The forces and torques transmitted between the masses, and the energy dissipated by the dampers were computed for several combinations of exciter frequencies and accelerations. The dependence of torques upon excitation agreed fairly well with the behaviour of the arm muscles under vibration as described by various investigators. At frequencies above 100 Hz the energy was dissipated mainly by the dampers between the masses near to the exciter. Transferring this result to the hand-arm system it shows that at high frequencies energy is dissipated by the hand and its palmar tissues and this might be one cause for the incidence of vibration-induced white finger disease.

Shoulder pain and concomitant hand oedema among stroke patients with pronounced arm paresis

PubMed Central

2013-01-01

Background The aim of this prospective study was to identify clinical factors associated with the development of shoulder pain in stroke patients with pronounced arm paresis. Methods At stroke onset, 485 patients were initially assessed in 2007–2009. Sixty-three patients with pronounced arm paresis completed the study, and 21 of these developed shoulder pain. Clinical findings were recorded fortnightly by the attending physiotherapist during hospital stay. Results Hand oedema on the paretic side was more common in patients developing shoulder pain compared with those who did not develop shoulder pain. The onset of shoulder pain was associated with concomitant hand oedema. High NIHSS score was associated with developing shoulder pain. Patients with a history of shoulder pain developed pain earlier than those without previous shoulder pain. Patients with haemorrhagic stroke were significantly more prone to developing shoulder pain. Conclusions One-third of the stroke patients with pronounced arm paresis developed shoulder pain. Concomitant hand oedema seems to be an additional symptom of shoulder injury. Patients with low general status are more vulnerable to develop post-stroke shoulder pain. PMID:24765589

Interethnic differences at the thermometric response to cold test: functional disorders of blood circulation in hand fingers and exposure to hand-arm vibration.

PubMed

Riolfi, A; Princivalle, A; Romeo, L; Caramaschi, P; Perbellini, L

2008-02-01

To report some notable aspects regarding thermometric response to cold test in black African subjects compared with Caucasians: both groups comprised persons exposed to hand-arm vibration and controls. An overall sample of 48 workers was examined in order to study their blood circulation in hand fingers: a control group of 12 healthy Caucasian workers never exposed before to hand-arm vibration; 12 Caucasian workers exposed for several years to vibrating tools and affected by occupational Raynaud's phenomenon; 12 healthy black African workers exposed to hand-arm vibration for almost 3 years; and 12 healthy black African workers never exposed to hand-arm vibration. Computerized skin thermometry was performed and thermometric curves were analyzed according to thermometric interpretation criteria such as the area-over-curve (AOC), the fifth minute of recovery/baseline temperature ratio (5REC/BT) and the temperature at the tenth minute of recovery (10REC) after cold test. Thermometric parameters in Caucasian subjects confirmed the basis of the existing literature in controls (basal finger temperature higher than 32 degrees C and complete recovery to the initial temperature after the cold test) and also in patients with Raynaud's phenomenon (basal temperature often lower than control subjects and slow recovery of finger temperature after cold test). Statistically significant difference was found between healthy Caucasians and healthy black subjects in all the parameters tested: healthy black subjects showed values of AOC and 10REC suggesting almost constantly lower finger temperatures during the thermometry test. Black people, both exposed and non-exposed to hand-arm vibration showed thermometric parameters suggesting poor blood microcirculation, which seems even poorer than in Caucasian people complaining Raynaud's phenomenon. Our chronothermometric tests suggest some significant interethnic differences in peripheral microcirculation, which seems rather poor in black

[Clinical features of the hand-arm vibration syndrome in miners].

PubMed

Kákosy, Tibor; Németh, László; Kiss, Gábor; Lászlóffy, Marianna; Kardos, Kálmán

2006-05-07

It is well known that the vibrating tools used by the miners can cause hand-arm vibration syndrome. However no detailed reports on this field could be found in the Hungarian literature. The aim of this study was to clarify the clinical features of the hand-arm vibration syndrome of the miners. The circulation, the peripheral nerves and the osteoarticular system of the upper extremities of 152 miners were examined by means of cold provocation test, Allen-test, measurement of systolic blood pressure performed by Doppler flowmeter, clinical neurological and neurographic examination and X-ray investigation of the bones and joints. Hand-arm vibration syndrome was diagnosed in 87 patients (57.2%). The most common symptom was the lesion of the circulation which occurred in 78 patients (89.6%). The peripheral nerves were affected in 44 cases (50.5%). Radiological alteration of the bones and joints of the upper extremities was observed in 32 patients (36.8%). Out of 78 damaged cases the frequency of the vascular diseases was as follows: angiopathy (diminished systolic blood pressure in the fingers): 66 patient (84.6%), occlusion of the hand arteries (positive Allen-test) and arterial form of the thoracic outlet syndrome (positive elevation-test) respectively: 28 and 28 cases (35.9%), Raynaud phenomenon (positive cold-provocation test): 26 cases (33.3%). The peripheral nerves were examined in detail in 141 cases. Pathological alterations were observed in 78 patients (55.3%) in the following forms: carpal tunnel syndrome: 66 cases (84.6%), peripheral neuropathy of the upper limbs: 20 patients (25.6%), lesion of the ulnar nerve: 3 cases (3.8%), brachial plexus lesion: one patient (1.3%). Radiological alteration was most common in the carpal region (87 cases, 57.2%). The frequency of the lesion of cubital (40.4%) and shoulder region (40.7%) was practically the same. In the carpal region the most common alterations were the degenerative processes (23 cases, 15.1%) followed by

Moving Events in Time: Time-Referent Hand-Arm Movements Influence Perceived Temporal Distance to Past Events

ERIC Educational Resources Information Center

Blom, Stephanie S. A. H.; Semin, Gun R.

2013-01-01

We examine and find support for the hypothesis that time-referent hand-arm movements influence temporal judgments. In line with the concept of "left is associated with earlier times, and right is associated with later times," we show that performing left (right) hand-arm movements while thinking about a past event increases (decreases) the…

Cognitive–Behavioral Therapy for Hand and Arm Pain

PubMed Central

Vranceanu, Ana-Maria; Safren, Steve

2016-01-01

Cognitive–behavioral therapy (CBT) is a psychological treatment that emphasizes the interrelation among thoughts, behaviors, feelings, and sensations. CBT has been proved effective not only for treatment of psychological illness but also for teaching adaptive coping strategies in the context of chronic illnesses, including chronic pain. The present article provides general information on CBT, specific information on CBT for pain, as well as guidelines and strategies for using CBT for hand and arm pain patients, as part of multidisciplinary care models. PMID:21051204

Establishment of one-axis vibration test system for measurement of biodynamic response of human hand-arm system.

PubMed

Shibata, Nobuyuki; Hosoya, Naoki; Maeda, Setsuo

2008-12-01

Prolonged exposure to hand-arm vibration (HAV) due to use of hand-held power tools leads to an increased occurrence of symptoms of disorders in the vascular, neurological, and osteo-articular systems of the upper limbs called hand-arm vibration syndrome (HAVS). Biodynamic responses of the hand-arm system to vibration can be suggestive parameters that give us better assessment of exposure to HAV and fundamental data for design of low-vibration-exposure power tools. Recently, a single axis hand-arm vibration system has been installed in the Japan National Institute of Occupational Safety and Health (NIOSH). The aims of this study were to obtain the fundamental dynamic characteristics of an instrumented handle and to validate the performance and measurement accuracy of the system applied to dynamic response measurement. A pseudo-random vibration signal with a frequency range of 5-1,250 Hz and a power spectrum density of 1.0 (m/s2)2/Hz was used in this study. First the dynamic response of the instrumented handle without any weight was measured. After this measurement, the dynamic response measurement of the handle with weights mounted on the handle was performed. The apparent mass of a weight itself was obtained by using the mass cancellation method. The mass of the measuring cap on the instrumented handle was well compensated by using the mass cancellation method. Based on the 10% error tolerance, this handle can reliably measure the dynamic response represented by an apparent mass with a minimum weight of 2.0 g in a frequency range of 10.0 to 1,000 Hz. A marked increase in the AM magnitude of the weights of 15 g and 20 g in frequency ranges greater than 800 Hz is attributed not to the fundamental resonance frequency of the handle with weights, but to the fixation of the weight to the measuring cap. In this aspect, the peak of the AM magnitude can be reduced and hence should not be an obstacle to the biodynamic response measurement of the human hand-arm system. On the

From Auto- to Allotransplantation: Immunomodulatory Protocol for Hand and Arm Transplantation.

PubMed

Lee, W P Andrew; Shores, Jaimie T; Brandacher, Gerald

2018-05-18

 To achieve a favorable risk-benefit balance for hand transplantation, an immunomodulatory protocol was developed in the laboratory and translated to clinical application.  Following donor bone marrow infusion into transplant recipients, hand and arm allografts have been maintained on low-dose tacrolimus monotherapy.  Good-to-excellent functional recovery has been achieved in patients compliant with medication and therapy, thus restoring autonomous and productive lives.  The risk-benefit balance can be tilted in favor of the hand transplant recipients by using an immunomodulatory protocol with minimum immunosuppression. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Correlations of Handgrip Strength with Selected Hand-Arm-Anthropometric Variables in Indian Inter-university Female Volleyball Players

PubMed Central

Koley, Shyamal; Pal Kaur, Satinder

2011-01-01

Purpose The purpose of this study was to estimate the dominant handgrip strength and its correlations with some hand and arm anthropometric variables in 101 randomly selected Indian inter-university female volleyball players aged 18-25 years (mean age 20.52±1.40) from six Indian universities. Methods Three anthropometric variables, i.e. height, weight, BMI, two hand anthropometric variables, viz. right and left hand width and length, four arm anthropometric variables, i.e. upper arm length, lower arm length, upper extremity length, upper arm circumference and dominant right and non-dominant handgrip strength were measured among Indian inter-university female volleyball players by standard anthropometric techniques. Results The findings of the present study indicated that Indian female volleyball players had higher mean values in eleven variables and lesser mean values in two variables than their control counterparts, showing significant differences (P<0.032-0.001) in height (t=2.63), weight (t=8.66), left hand width (t=2.10), left and right hand length (t=9.99 and 10.40 respectively), right upper arm length (t=8.48), right forearm length (t=5.41), dominant (right) and non-dominant (left) handgrip strength (t=9.37 and 6.76 respectively). In female volleyball players, dominant handgrip strength had significantly positive correlations (P=0.01) with all the variables studied. Conclusion It may be concluded that dominant handgrip strength had strong positive correlations with all the variables studied in Indian inter-university female volleyball players. PMID:22375242

[The combined use of capillaroscopy and skin thermometry in health surveillance of workers exposed to hand-arm vibration].

PubMed

Riolfi, A; Perbellini, L

2010-01-01

The use of nailfold capillaroscopy combined with skin thermometry in the study of microcirculation of the hands in workers exposed to hand-arm vibration is assessed. Fifty-eight subjects were studied; 40 asymptomatic forestry workers exposed to hand-arm vibration, 13 forestry workers exposed to hand-arm vibration with Raynaud-like symptoms confirmed by skin thermometry; 5 controls. Reduction of capillary density was observed in workers exposed to vibrating tools with respect to controls. Tortuosity of capillary loops was significantly more frequent in subjects exposed to vibrating tools than in controls. No statistically significant difference in capillary vessels of the hands was found between asymptomatic exposed subjects and workers affected by Raynaud-like symptoms. In our sample nailfold capillaroscopy shows good sensibilty and specificity in detecting capillary modifications secondary to exposure to hand-vibration. Weaker evidence is instead given in order to actual disturbances of hands circulation in chronic exposure to vibrating tools.

The Effects of Unit Exercises on the Hand Grip Strength of Arm Wrestlers

ERIC Educational Resources Information Center

Yonca, Sezer S.; Engin, Çelikel B.; Serdar, Yücel A.; Mustafa, Karadag; Yüksel, Savucu

2017-01-01

The aim of this research is to evaluate the change in the hand grip strength of the male arm wrestlers before and after a unit of exercise. The participants of the research consist of sportsmen (n=16) of Firat University arm wrestling team in 18-25 age group. Within the scope of the research, all of the tests and measurements (age, length, body…

Simultaneously measured inter-arm and inter-leg systolic blood pressure differences and cardiovascular risk stratification: a systemic review and meta-analysis.

PubMed

Singh, Sukhchain; Sethi, Ankur; Singh, Mukesh; Khosla, Kavia; Grewal, Navsheen; Khosla, Sandeep

2015-08-01

Association of inter-arm systolic blood pressure difference (IASBPD) with cardiovascular (CV) morbidity and mortality remains controversial. We aimed to thoroughly examine all available evidence on inter-limb blood pressure (BP) difference and its association with CV risk and outcomes. We searched PubMed, EMBASE, CINAHL, Cochrane library, and Ovid for studies reporting bilateral simultaneous BP measurements in arms or legs and risk of peripheral arterial disease (PAD), coronary artery disease, cerebrovascular disease, subclavian stenosis, or mortality. Random-effect meta-analysis was performed to compare effect estimates. Twenty-seven studies met inclusion criteria, but only 17 studies (18 cohorts) were suitable for analysis. IASBPD of 10 mmHg or more was associated with PAD (risk ratios, 2.22; 1.41-3.5; P = .0006; sensitivity 16.6%; 6.7-35.4; specificity 91.9%; 83.1-96.3; 8 cohorts; 4774 subjects), left ventricular mass index (standardized mean difference 0.21; 0.03-0.39; P = .02; 2 cohort; 1604 subjects), and brachial-ankle pulse wave velocity (PWV) (one cohort). Association of PAD remained significant at cutoff of 15 mmHg (risk ratios, 1.91; 1.28-2.84; P = .001; 5 cohorts; 1914 subjects). We could not find statistically significant direct association of coronary artery disease, cerebrovascular disease, CV, and all-cause mortality in subjects with IASBPD of 10 mmHg or more, 15 mmHg or more, and inter-leg systolic BP difference of 15 mmHg or more. Inter-leg BP difference of 15 mmHg or more was strong predictor of PAD (P = .0001) and brachial-ankle PWV (P = .0001). Two invasive studies showed association of IASBPD and subclavian stenosis (estimates could not be combined). In conclusion, inter-arm and leg BP differences are strong predictors of PAD. IASBPD may be associated with subclavian stenosis, high left ventricular mass effect, and higher brachial-ankle PWVs. Inter-leg BP difference may also be associated with high left ventricular mass effect and higher

Linear modeling of human hand-arm dynamics relevant to right-angle torque tool interaction.

PubMed

Ay, Haluk; Sommerich, Carolyn M; Luscher, Anthony F

2013-10-01

A new protocol was evaluated for identification of stiffness, mass, and damping parameters employing a linear model for human hand-arm dynamics relevant to right-angle torque tool use. Powered torque tools are widely used to tighten fasteners in manufacturing industries. While these tools increase accuracy and efficiency of tightening processes, operators are repetitively exposed to impulsive forces, posing risk of upper extremity musculoskeletal injury. A novel testing apparatus was developed that closely mimics biomechanical exposure in torque tool operation. Forty experienced torque tool operators were tested with the apparatus to determine model parameters and validate the protocol for physical capacity assessment. A second-order hand-arm model with parameters extracted in the time domain met model accuracy criterion of 5% for time-to-peak displacement error in 93% of trials (vs. 75% for frequency domain). Average time-to-peak handle displacement and relative peak handle force errors were 0.69 ms and 0.21%, respectively. Model parameters were significantly affected by gender and working posture. Protocol and numerical calculation procedures provide an alternative method for assessing mechanical parameters relevant to right-angle torque tool use. The protocol more closely resembles tool use, and calculation procedures demonstrate better performance of parameter extraction using time domain system identification methods versus frequency domain. Potential future applications include parameter identification for in situ torque tool operation and equipment development for human hand-arm dynamics simulation under impulsive forces that could be used for assessing torque tools based on factors relevant to operator health (handle dynamics and hand-arm reaction force).

Hand-arm vibration syndrome: a common occupational hazard in industrialized countries.

PubMed

Heaver, C; Goonetilleke, K S; Ferguson, H; Shiralkar, S

2011-06-01

Regular exposure to hand-transmitted vibration can result in symptoms and signs of peripheral vascular, neurological and other disorders collectively known as the hand-arm vibration syndrome (HAVS). A significant proportion of workers can suffer from HAVS after using vibrating power tools. HAVS is a chronic and progressive disorder. Early recognition and prevention is the key to managing vibrating tool exposures and health effects. This article gives a broad overview of the condition with a detailed account of its pathogenesis, identification and management.

Virtual Reality to Maximize Function for Hand and Arm Rehabilitation: Exploration of Neural Mechanisms

PubMed Central

MERIANS, Alma S.; TUNIK, Eugene; ADAMOVICH, Sergei V.

2015-01-01

Stroke patients report hand function as the most disabling motor deficit. Current evidence shows that learning new motor skills is essential for inducing functional neuroplasticity and functional recovery. Adaptive training paradigms that continually and interactively move a motor outcome closer to the targeted skill are important to motor recovery. Computerized virtual reality simulations when interfaced with robots, movement tracking and sensing glove systems are particularly adaptable, allowing for online and offline modifications of task based activities using the participant’s current performance and success rate. We have developed a second generation system that can exercise the hand and the arm together or in isolation and provides for both unilateral and bilateral hand and arm activities in three-dimensional space. We demonstrate that by providing haptic assistance for the hand and arm and adaptive anti-gravity support, the system can accommodate patients with lower level impairments. We hypothesize that combining training in VE with observation of motor actions can bring additional benefits. We present a proof of concept of a novel system that integrates interactive VE with functional neuroimaging to address this issue. Three components of this system are synchronized, the presentation of the visual display of the virtual hands, the collection of fMRI images and the collection of hand joint angles from the instrumented gloves. We show that interactive VEs can facilitate activation of brain areas during training by providing appropriately modified visual feedback. We predict that visual augmentation can become a tool to facilitate functional neuroplasticity. PMID:19592790

The metabolic cost of human running: is swinging the arms worth it?

PubMed

Arellano, Christopher J; Kram, Rodger

2014-07-15

Although the mechanical function is quite clear, there is no consensus regarding the metabolic benefit of arm swing during human running. We compared the metabolic cost of running using normal arm swing with the metabolic cost of running while restricting the arms in three different ways: (1) holding the hands with the arms behind the back in a relaxed position (BACK), (2) holding the arms across the chest (CHEST) and (3) holding the hands on top of the head (HEAD). We hypothesized that running without arm swing would demand a greater metabolic cost than running with arm swing. Indeed, when compared with running using normal arm swing, we found that net metabolic power demand was 3, 9 and 13% greater for the BACK, CHEST and HEAD conditions, respectively (all P<0.05). We also found that when running without arm swing, subjects significantly increased the peak-to-peak amplitudes of both shoulder and pelvis rotation about the vertical axis, most likely a compensatory strategy to counterbalance the rotational angular momentum of the swinging legs. In conclusion, our findings support our general hypothesis that swinging the arms reduces the metabolic cost of human running. Our findings also demonstrate that arm swing minimizes torso rotation. We infer that actively swinging the arms provides both metabolic and biomechanical benefits during human running. © 2014. Published by The Company of Biologists Ltd.

Phase-dependent organization of postural adjustments associated with arm movements while walking.

PubMed

Nashner, L M; Forssberg, H

1986-06-01

This study examines the interactions between anteroposterior postural responses and the control of walking in human subjects. In the experimental paradigm, subjects walked upon a treadmill, gripping a rigid handle with one hand. Postural responses at different phases of stepping were elicited by rapid arm pulls or pushes against the handle. During arm movements, EMG's recorded the activity of representative arm, ankle, and thigh segment muscles. Strain gauges in the handle measured the force of the arm movement. A Selspot II system measured kinematics of the stepping movements. The duration of support and swing phases were marked by heel and toe switches in the soles of the subjects' shoes. In the first experiment, subjects were instructed to pull on the handle at their own pace. In these trials all subjects preferred to initiate pulls near heel strikes. Next, when instructed to pull as rapidly as possible in response to tone stimuli, reaction times were similar for all phases of the step cycle. Leg muscle responses associated with arm pulls and pushes, referred to as "postural activations," were directionally specific and preceded arm muscle activity. The temporal order and spatial distribution of postural activations in the muscles of the support leg were similar when arm pull movements occurred while the subject was standing in place and after heel strike while walking. Activations began in the ankle and radiated proximally to the thigh and then the arm. Activations of swing leg muscles were also directionally specific and involved flexion and forward or backward thrust of the limb. When arm movements were initiated during transitions from support by one leg to the other, patterns of postural activations were altered. Alterations usually occurred 10-20 ms before hell strikes and involved changes in the timing and sometimes the spatial structure of postural activations. Postural activation patterns are similar during in-place standing and during the support phase

Robot-Assisted Training of Arm and Hand Movement Shows Functional Improvements for Incomplete Cervical Spinal Cord Injury.

PubMed

Francisco, Gerard E; Yozbatiran, Nuray; Berliner, Jeffrey; OʼMalley, Marcia K; Pehlivan, Ali Utku; Kadivar, Zahra; Fitle, Kyle; Boake, Corwin

2017-10-01

The aim of the study was to demonstrate the feasibility, tolerability, and effectiveness of robotic-assisted arm training in incomplete chronic tetraplegia. Pretest/posttest/follow-up was conducted. Ten individuals with chronic cervical spinal cord injury were enrolled. Participants performed single degree-of-freedom exercise of upper limbs at an intensity of 3-hr per session for 3 times a week for 4 wks with MAHI Exo-II. Arm and hand function tests (Jebsen-Taylor Hand Function Test, Action Research Arm Test), strength of upper limb (upper limb motor score, grip, and pinch strength), and independence in daily living activities (Spinal Cord Independence Measure II) were performed at baseline, end of training, and 6 mos later. After 12 sessions of training, improvements in arm and hand functions were observed. Jebsen-Taylor Hand Function Test (0.14[0.04]-0.21[0.07] items/sec, P = 0.04), Action Research Arm Test (30.7[3.8]-34.3[4], P = 0.02), American Spinal Injury Association upper limb motor score (31.5[2.3]-34[2.3], P = 0.04) grip (9.7[3.8]-12[4.3] lb, P = 0.02), and pinch strength (4.5[1.1]-5.7[1.2] lb, P = 0.01) resulted in significant increases. Some gains were maintained at 6 mos. No change in Spinal Cord Independence Measure II scores and no adverse events were observed. Results from this pilot study suggest that repetitive training of arm movements with MAHI Exo-II exoskeleton is safe and has potential to be an adjunct treatment modality in rehabilitation of persons with spinal cord injury with mild to moderate impaired arm functions.

[Pulse wave velocity of the leg minus that of the arm measured with a custom device correlates to the coronary calcium quantification].

PubMed

Rico Martín, S; de Nicolás Jiménez, J M; Moyano Calvente, S L; Mogollón Jiménez, M V; Vega Fernández, J; Calderón García, J F; Bacaicoa Lopez de Sabando, M A; Tardio, M; Sánchez Muñoz-Torrero, J F

2016-05-01

The pulse wave velocity (PWV) in the great arteries is an indicator of vascular risk. Our objective was to identify the PWV index between the arms and legs that best correlates with the coronary calcium quantification (CCQ) and to compare it with other methods. Eight-one patients without vascular disease underwent the following measurements: CCQ; carotid intima-media thickness (IMT); carotid-femoral PWV (cfPWV), using COMPLIOR; and PWV in the arms and legs, with our own device (abiPWV, ankle brachial index PWV). The difference in PWVs between the leg and arm (l-a PWV) measured with abiPWV was the index that best correlated with CCQ (r=0.401, P<.001). The correlation between IMT and CCQ and between CF-PWV and CCQ were r=0.366, P=.001; and r=0.385, P=.001, respectively. For a CCQ score higher than 100 as a marker of significant coronary arteriosclerosis, the areas under the curve for l-a PWV, IMT and cfPWV were 0.721 (P=.002), 0.758 (P<.001) and 0.636 (P=.058), respectively. For patients without vascular disease, the l-a PWV measured with abiPWV appears to be the index that best correlates with the CCQ. This association is comparable to that between IMT and CCQ and between cfPWV and CCQ. The abiPWV is an easy-to-use device that can help improve vascular risk stratification. Copyright © 2016 Elsevier España, S.L.U. y Sociedad Española de Medicina Interna (SEMI). All rights reserved.

The effect of swinging the arms on muscle activation and production of leg force during ski skating at different skiing speeds.

PubMed

Göpfert, Caroline; Lindinger, Stefan J; Ohtonen, Olli; Rapp, Walter; Müller, Erich; Linnamo, Vesa

2016-06-01

The study investigated the effects of arm swing during leg push-off in V2-alternate/G4 skating on neuromuscular activation and force production by the leg muscles. Nine skilled cross-country skiers performed V2-alternate skating without poles at moderate, high, and maximal speeds, both with free (SWING) and restricted arm swing (NOSWING). Maximal speed was 5% greater in SWING (P<0.01), while neuromuscular activation and produced forces did not differ between techniques. At both moderate and high speed the maximal (2% and 5%, respectively) and average (both 5%) vertical force and associated impulse (10% and 14%) were greater with SWING (all P<0.05). At high speed range of motion and angular velocity of knee flexion were 24% greater with SWING (both P<0.05), while average EMG of m. biceps femoris was 31% lower (all P<0.05) in SWING. In a similar manner, the average EMG of m. vastus medialis and m. biceps femoris were lower (17% and 32%, P<0.05) during the following knee extension. Thus, swinging the arms while performing V2-alternate can enhance both maximal speed and skiing economy at moderate and, in particularly, high speeds. Copyright © 2016 Elsevier B.V. All rights reserved.

An examination of the vibration transmissibility of the hand-arm system in three orthogonal directions.

PubMed

Welcome, Daniel E; Dong, Ren G; Xu, Xueyan S; Warren, Christopher; McDowell, Thomas W; Wu, John Z

2015-02-01

The objective of this study is to enhance the understanding of the vibration transmission in the hand-arm system in three orthogonal directions ( X, Y , and Z ). For the first time, the transmitted vibrations distributed on the entire hand-arm system exposed in the three orthogonal directions via a 3-D vibration test system were measured using a 3-D laser vibrometer. Seven adult male subjects participated in the experiment. This study confirms that the vibration transmissibility generally decreased with the increase in distance from the hand and it varied with the vibration direction. Specifically, to the upper arm and shoulder, only moderate vibration transmission was measured in the test frequency range (16 to 500 Hz), and virtually no transmission was measured in the frequency range higher than 50 Hz. The resonance vibration on the forearm was primarily in the range of 16-30 Hz with the peak amplitude of approximately 1.5 times of the input vibration amplitude. The major resonance on the dorsal surfaces of the hand and wrist occurred at around 30-40 Hz and, in the Y direction, with peak amplitude of more than 2.5 times of the input amplitude. At higher than 50 Hz, vibration transmission was effectively limited to the hand and fingers. A major finger resonance was observed at around 100 Hz in the X and Y directions and around 200 Hz in the Z direction. In the fingers, the resonance magnitude in the Z direction was generally the lowest, and the resonance magnitude in the Y direction was generally the highest with the resonance amplitude of 3 times the input vibration, which was similar to the transmissibility at the wrist and hand dorsum. The implications of the results are discussed. Prolonged, intensive exposure to hand-transmitted vibration could result in hand-arm vibration syndrome. While the syndrome's precise mechanisms remain unclear, the characterization of the vibration transmissibility of the system in the three orthogonal dimensions performed in this

An examination of the vibration transmissibility of the hand-arm system in three orthogonal directions

PubMed Central

Welcome, Daniel E.; Dong, Ren G.; Xu, Xueyan S.; Warren, Christopher; McDowell, Thomas W.; Wu, John Z.

2015-01-01

The objective of this study is to enhance the understanding of the vibration transmission in the hand-arm system in three orthogonal directions (X, Y, and Z). For the first time, the transmitted vibrations distributed on the entire hand-arm system exposed in the three orthogonal directions via a 3-D vibration test system were measured using a 3-D laser vibrometer. Seven adult male subjects participated in the experiment. This study confirms that the vibration transmissibility generally decreased with the increase in distance from the hand and it varied with the vibration direction. Specifically, to the upper arm and shoulder, only moderate vibration transmission was measured in the test frequency range (16 to 500 Hz), and virtually no transmission was measured in the frequency range higher than 50 Hz. The resonance vibration on the forearm was primarily in the range of 16–30 Hz with the peak amplitude of approximately 1.5 times of the input vibration amplitude. The major resonance on the dorsal surfaces of the hand and wrist occurred at around 30–40 Hz and, in the Y direction, with peak amplitude of more than 2.5 times of the input amplitude. At higher than 50 Hz, vibration transmission was effectively limited to the hand and fingers. A major finger resonance was observed at around 100 Hz in the X and Y directions and around 200 Hz in the Z direction. In the fingers, the resonance magnitude in the Z direction was generally the lowest, and the resonance magnitude in the Y direction was generally the highest with the resonance amplitude of 3 times the input vibration, which was similar to the transmissibility at the wrist and hand dorsum. The implications of the results are discussed. Relevance to industry Prolonged, intensive exposure to hand-transmitted vibration could result in hand-arm vibration syndrome. While the syndrome's precise mechanisms remain unclear, the characterization of the vibration transmissibility of the system in the three orthogonal

Leg size and muscle functions associated with leg compliance

NASA Technical Reports Server (NTRS)

Convertino, Victor A.; Doerr, Donald F.; Flores, Jose F.; Hoffler, G. Wyckliffe; Buchanan, Paul

1988-01-01

The relationship between the leg compliance and factors related to the size of leg muscle and to physical fitness was investigated in ten healthy subjects. Vascular compliance of the leg, as determined by a mercury strain gauge, was found to be not significantly correlated with any variables associated with physical fitness per se (e.g., peak O2 uptake, calf strength, age, body weight, or body composition. On the other hand, leg compliance correlated with the calf cross-sectional area (CSA) and the calculated calf volume, with the CSA of calf muscle being the most dominant contributing factor (while fat and bone were poor predicators). It is suggested that leg compliance can be lowered by increasing calf muscle mass, thus providing structural support to limit the expansion of leg veins.

Activation timing of postural muscles of lower legs and prediction of postural disturbance during bilateral arm flexion in older adults.

PubMed

Yaguchi, Chie; Fujiwara, Katsuo; Kiyota, Naoe

2017-12-22

Activation timings of postural muscles of lower legs and prediction of postural disturbance were investigated in young and older adults during bilateral arm flexion in a self-timing task and an oddball task with different probabilities of target presentation. Arm flexion was started from a standing posture with hands suspended 10 cm below the horizontal level in front of the body, in which postural control focused on the ankles is important. Fourteen young and 14 older adults raised the arms in response to the target sound signal. Three task conditions were used: 15 and 45% probabilities of the target in the oddball task and self-timing. Analysis items were activation timing of postural muscles (erector spinae, biceps femoris, and gastrocnemius) with respect to the anterior deltoid (AD), and latency and amplitude of the P300 component of event-related brain potential. For young adults, all postural muscles were activated significantly earlier than AD under each condition, and time of preceding gastrocnemius activation was significantly longer in the order of the self-timing, 45 and 15% conditions. P300 latency was significantly shorter, and P300 amplitude was significantly smaller under the 45% condition than under the 15% condition. For older adults, although all postural muscles, including gastrocnemius, were activated significantly earlier than AD in the self-timing condition, only activation timing of gastrocnemius was not significantly earlier than that of AD in oddball tasks, regardless of target probability. No significant differences were found between 15 and 45% conditions in onset times of all postural muscles, and latency and amplitude of P300. These results suggest that during arm movement, young adults can achieve sufficient postural preparation in proportion to the probability of target presentation in the oddball task. Older adults can achieve postural control using ankle joints in the self-timing task. However, in the oddball task, older adults

Loss of Productivity Due to Neck/Shoulder Symptoms and Hand/Arm Symptoms: Results from the PROMO-Study

PubMed Central

IJmker, Stefan; Blatter, Birgitte M.; de Korte, Elsbeth M.

2007-01-01

Introduction The objective of the present study is to describe the extent of productivity loss among computer workers with neck/shoulder symptoms and hand/arm symptoms, and to examine associations between pain intensity, various physical and psychosocial factors and productivity loss in computer workers with neck/shoulder and hand/arm symptoms. Methods A cross-sectional design was used. The study population consisted of 654 computer workers with neck/shoulder or hand/arm symptoms from five different companies. Descriptive statistics were used to describe the occurrence of self-reported productivity loss. Logistic regression analyses were used to examine the associations. Results In 26% of all the cases reporting symptoms, productivity loss was involved, the most often in cases reporting both symptoms (36%). Productivity loss involved sickness absence in 11% of the arm/hand cases, 32% of the neck/shoulder cases and 43% of the cases reporting both symptoms. The multivariate analyses showed statistically significant odds ratios for pain intensity (OR: 1.26; CI: 1.12–1.41), for high effort/no low reward (OR: 2.26; CI: 1.24–4.12), for high effort/low reward (OR: 1.95; CI: 1.09–3.50), and for low job satisfaction (OR: 3.10; CI: 1.44–6.67). Physical activity in leisure time, full-time work and overcommitment were not associated with productivity loss. Conclusion In most computer workers with neck/shoulder symptoms or hand/arm symptoms productivity loss derives from a decreased performance at work and not from sickness absence. Favorable psychosocial work characteristics might prevent productivity loss in symptomatic workers. PMID:17636455

Learning robotic eye-arm-hand coordination from human demonstration: a coupled dynamical systems approach.

PubMed

Lukic, Luka; Santos-Victor, José; Billard, Aude

2014-04-01

We investigate the role of obstacle avoidance in visually guided reaching and grasping movements. We report on a human study in which subjects performed prehensile motion with obstacle avoidance where the position of the obstacle was systematically varied across trials. These experiments suggest that reaching with obstacle avoidance is organized in a sequential manner, where the obstacle acts as an intermediary target. Furthermore, we demonstrate that the notion of workspace travelled by the hand is embedded explicitly in a forward planning scheme, which is actively involved in detecting obstacles on the way when performing reaching. We find that the gaze proactively coordinates the pattern of eye-arm motion during obstacle avoidance. This study provides also a quantitative assessment of the coupling between the eye-arm-hand motion. We show that the coupling follows regular phase dependencies and is unaltered during obstacle avoidance. These observations provide a basis for the design of a computational model. Our controller extends the coupled dynamical systems framework and provides fast and synchronous control of the eyes, the arm and the hand within a single and compact framework, mimicking similar control system found in humans. We validate our model for visuomotor control of a humanoid robot.

Hand-arm Vibration Effects on Performance, Tactile Acuity, and Temperature of Hand

PubMed Central

Forouharmajd, Farhad; Yadegari, Mehrdad; Ahmadvand, Masoumeh; Forouharmajd, Farshad; Pourabdian, Siamak

2017-01-01

Effects of vibration appear as mechanical and psychological disorders, including stress reactions, cognitive and movement disorders, problem in concentration and paying attention to the assigned duties. The common signs and symptoms of hand-arm vibration (HAV) in the fingers and hands may appear as pins and needles feeling, tingling, numbness, and also the loss of finger sensation and dexterity. Laboratory Virtual Instrument Engineering Workbench programming software designed for occupational vibrations measurement was used to calculate HAV acceleration. Hole steadiness test is designed to measure involuntary movement of people. V-Pieron test is designed for one of the other aspects of the psycho motor phenomena of steadiness by moving the stylus across a V-form ruler. The two points test was an experiment of touch acuity, which used a caliper by placing the two styli very close on the pad of finger knuckles. The temperature of finger skin is also measured simultaneous to the above tests. Wilcoxon test indicated that a significant decrement in hand steadiness occurred after gripping a vibrating handle for 2 min (P ≤ 0.003). Wilcoxon test also represented a significant change in errors after gripping a grinder vibratory handle (P ≤ 0.003). The differences at all of the knuckles were significant with a confidence interval percentage of 99%. There was a significant reduction in finger skin temperature before and after exposure to vibration (mean = 0.45°C, based on paired sample test). The obtained results considerably demonstrated the relation between hand performance and vibrations due to gripping a grinder. It can be concluded that an injury or accident may happen after exposure to vibrations for the fine duties, in fast actions. PMID:29204383

Hand-arm Vibration Effects on Performance, Tactile Acuity, and Temperature of Hand.

PubMed

Forouharmajd, Farhad; Yadegari, Mehrdad; Ahmadvand, Masoumeh; Forouharmajd, Farshad; Pourabdian, Siamak

2017-01-01

Effects of vibration appear as mechanical and psychological disorders, including stress reactions, cognitive and movement disorders, problem in concentration and paying attention to the assigned duties. The common signs and symptoms of hand-arm vibration (HAV) in the fingers and hands may appear as pins and needles feeling, tingling, numbness, and also the loss of finger sensation and dexterity. Laboratory Virtual Instrument Engineering Workbench programming software designed for occupational vibrations measurement was used to calculate HAV acceleration. Hole steadiness test is designed to measure involuntary movement of people. V-Pieron test is designed for one of the other aspects of the psycho motor phenomena of steadiness by moving the stylus across a V-form ruler. The two points test was an experiment of touch acuity, which used a caliper by placing the two styli very close on the pad of finger knuckles. The temperature of finger skin is also measured simultaneous to the above tests. Wilcoxon test indicated that a significant decrement in hand steadiness occurred after gripping a vibrating handle for 2 min ( P ≤ 0.003). Wilcoxon test also represented a significant change in errors after gripping a grinder vibratory handle ( P ≤ 0.003). The differences at all of the knuckles were significant with a confidence interval percentage of 99%. There was a significant reduction in finger skin temperature before and after exposure to vibration (mean = 0.45°C, based on paired sample test). The obtained results considerably demonstrated the relation between hand performance and vibrations due to gripping a grinder. It can be concluded that an injury or accident may happen after exposure to vibrations for the fine duties, in fast actions.

Quantitatively measured tremor in hand-arm vibration-exposed workers.

PubMed

Edlund, Maria; Burström, Lage; Hagberg, Mats; Lundström, Ronnie; Nilsson, Tohr; Sandén, Helena; Wastensson, Gunilla

2015-04-01

The aim of the present study was to investigate the possible increase in hand tremor in relation to hand-arm vibration (HAV) exposure in a cohort of exposed and unexposed workers. Participants were 178 male workers with or without exposure to HAV. The study is cross-sectional regarding the outcome of tremor and has a longitudinal design with respect to exposure. The dose of HAV exposure was collected via questionnaires and measurements at several follow-ups. The CATSYS Tremor Pen(®) was used for measuring postural tremor. Multiple linear regression methods were used to analyze associations between different tremor variables and HAV exposure, along with predictor variables with biological relevance. There were no statistically significant associations between the different tremor variables and cumulative HAV or current exposure. Age was a statistically significant predictor of variation in tremor outcomes for three of the four tremor variables, whereas nicotine use was a statistically significant predictor of either left or right hand or both hands for all four tremor variables. In the present study, there was no evidence of an exposure-response association between HAV exposure and measured postural tremor. Increase in age and nicotine use appeared to be the strongest predictors of tremor.

A Biomechanical Assessment of Hand/Arm Force with Pneumatic Nail Gun Actuation Systems.

PubMed

Lowe, Brian D; Albers, James; Hudock, Stephen D

2014-09-01

A biomechanical model is presented, and combined with measurements of tip press force, to estimate total user hand force associated with two pneumatic nail gun trigger systems. The contact actuation trigger (CAT) can fire a nail when the user holds the trigger depressed first and then "bumps" the nail gun tip against the workpiece. With a full sequential actuation trigger (SAT) the user must press the tip against the workpiece prior to activating the trigger. The SAT is demonstrably safer in reducing traumatic injury risk, but increases the duration (and magnitude) of tip force exertion. Time integrated (cumulative) hand force was calculated for a single user from measurements of the tip contact force with the workpiece and transfer time between nails as inputs to a static model of the nail gun and workpiece in two nailing task orientations. The model shows the hand force dependence upon the orientation of the workpiece in addition to the trigger system. Based on standard time allowances from work measurement systems (i.e. Methods-Time Measurement - 1) it is proposed that efficient application of hand force with the SAT in maintaining tip contact can reduce force exertion attributable to the sequential actuation trigger to 2-8% (horizontal nailing) and 9-20% (vertical nailing) of the total hand/arm force. The present model is useful for considering differences in cumulative hand/arm force exposure between the SAT and CAT systems and may explain the appeal of the CAT trigger in reducing the user's perception of muscular effort.

A Biomechanical Assessment of Hand/Arm Force with Pneumatic Nail Gun Actuation Systems

PubMed Central

Lowe, Brian D.; Albers, James; Hudock, Stephen D.

2015-01-01

A biomechanical model is presented, and combined with measurements of tip press force, to estimate total user hand force associated with two pneumatic nail gun trigger systems. The contact actuation trigger (CAT) can fire a nail when the user holds the trigger depressed first and then “bumps” the nail gun tip against the workpiece. With a full sequential actuation trigger (SAT) the user must press the tip against the workpiece prior to activating the trigger. The SAT is demonstrably safer in reducing traumatic injury risk, but increases the duration (and magnitude) of tip force exertion. Time integrated (cumulative) hand force was calculated for a single user from measurements of the tip contact force with the workpiece and transfer time between nails as inputs to a static model of the nail gun and workpiece in two nailing task orientations. The model shows the hand force dependence upon the orientation of the workpiece in addition to the trigger system. Based on standard time allowances from work measurement systems (i.e. Methods-Time Measurement - 1) it is proposed that efficient application of hand force with the SAT in maintaining tip contact can reduce force exertion attributable to the sequential actuation trigger to 2–8% (horizontal nailing) and 9–20% (vertical nailing) of the total hand/arm force. The present model is useful for considering differences in cumulative hand/arm force exposure between the SAT and CAT systems and may explain the appeal of the CAT trigger in reducing the user’s perception of muscular effort. PMID:26321780

Vascular hand-arm vibration syndrome--magnetic resonance angiography.

PubMed

Poole, C J M; Cleveland, T J

2016-01-01

The diagnosis of vascular hand-arm vibration syndrome (HAVS) requires consistent symptoms, photographic evidence of digital blanching and sufficient exposure to hand-transmitted vibration (HTV; A(8) > 2.5 m/s2). There is no reliable quantitative investigation for distinguishing HAVS from other causes of Raynaud's phenomenon and from normal individuals. Hypothenar and thenar hammer syndromes produce similar symptoms to HAVS but are difficult to diagnose clinically and may be confused with HAVS. Magnetic resonance angiography (MRA) is a safe and minimally invasive method of visualizing blood vessels. Three cases of vascular HAVS are described in which MRA revealed occlusions of the ulnar, radial and superficial palmar arteries. It is proposed that HTV was the cause of these occlusions, rather than blows to the hand unrelated to vibration, the assumed mechanism for the hammer syndromes. All three cases were advised not to expose their hands to HTV despite one of them being at Stockholm vascular stage 2 (early). MRA should be the investigation of choice for stage 2 vascular HAVS or vascular HAVS with unusual features or for a suspected hammer syndrome. The technique is however technically challenging and best done in specialist centres in collaboration with an occupational physician familiar with the examination of HAVS cases. Staging for HAVS should be developed to include anatomical arterial abnormalities as well as symptoms and signs of blanching. Workers with only one artery supplying a hand, or with only one palmar arch, may be at increased risk of progression and therefore should not be exposed to HTV irrespective of their Stockholm stage. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The relation of hand and arm configuration variances while tracking geometric figures in Parkinson's disease: aspects for rehabilitation.

PubMed

Keresztényi, Zoltán; Cesari, Paola; Fazekas, Gábor; Laczkó, József

2009-03-01

Variances of drawing arm movements between patients with Parkinson's disease and healthy controls were compared. The aim was to determine whether differences in joint synergies or individual joint rotations affect the endpoint (hand position) variance. Joint and endpoint coordinates were measured while participants performed drawing tasks. Variances of arm configurations and endpoints were computed and statistically analyzed for 12 patients and 12 controls. The variance of arm movements for patients (both for arm configuration and endpoint) was overall higher than that for the control group. Variation was smaller for drawing a circle versus a square and for drawing with the dominant versus the nondominant hand within both groups. The ratio of arm configuration variances between groups was similar to the ratio of endpoint variances. There were significant differences in the velocity, but not in the path lengths of movements comparing the two groups. Patients presented less movement stability while drawing different figures in different trials. Moreover, the similarity of the ratios suggests that the ill-coordinated hand movement was caused by the error in the movements of individual body parts rather than by the lack of intersegmental coordination. Thus, rehabilitation may focus on the improvement of the precision of individual joint rotations.

Arm and Hand Movement in Children Suspected of Having Autism Spectrum Disorder

ERIC Educational Resources Information Center

Braddock, Barbara A.; Hilton, Jane C.

2016-01-01

The aim of this study was to describe arm and hand movement in children suspected of having autism spectrum disorder (ASD; age range 29-43 months). A videotaped retrospective review of five children with symptoms of ASD during "Communication Temptation Tasks" was completed at two time points (pre-testing and 6 weeks later). Categories of…

Prevention and treatment of exercise related leg pain in young soldiers; a review of the literature and current practice in the Dutch Armed Forces.

PubMed

Zimmermann, Wes O; Helmhout, P H; Beutler, A

2017-04-01

Overuse injuries of the leg are a common problem for young soldiers. This article reviews the literature concerning the prevention and treatment of exercise related leg pain in military settings and presents the latest developments in proposed mechanisms and treatments. Current practice and treatment protocols from the Dutch Armed Forces are reviewed, with an emphasis on the most prevalent conditions of medial tibial stress syndrome and chronic exertional compartment syndrome. The conclusion is that exercise related leg pain in the military is an occupational problem that deserves further study. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Hand-arm vibration exposure monitoring with wearable sensor module.

PubMed

Austad, Hanne O; Røed, Morten H; Liverud, Anders E; Dalgard, Steffen; Seeberg, Trine M

2013-01-01

Vibration exposure is a serious risk within work physiology for several work groups. Combined with cold artic climate, the risk for permanent harm is even higher. Equipment that can monitor the vibration exposure and warn the user when at risk will provide a safer work environment for these work groups. This study evaluates whether data from a wearable wireless multi-parameter sensor module can be used to estimate vibration exposure and exposure time. This work has been focused on the characterization of the response from the accelerometer in the sensor module and the optimal location of the module in the hand-arm configuration.

[The hand-arm vibration syndrome: (II). The diagnostic aspects and fitness criteria].

PubMed

Bovenzi, M

1999-01-01

Part II of this paper reviews the clinical and laboratory methods to diagnose the neurological, vascular and osteoarticular components of the hand-arm vibration syndrome. The prognosis and reversibility of vibration-induced neurological and vascular disorders after cessation of vibration exposure or the introduction of powered tools equipped with vibration isolation systems are discussed on the basis of the results of follow-up clinical investigations and longitudinal epidemiologic studies. Finally, the review debates some of the methodological aspects connected with the health surveillance of vibration-exposed workers and considers the possible medical contra-indications for prolonged exposure to hand-transmitted vibration.

Relationship between self-reported upper limb disability and quantitative tests in hand-arm vibration syndrome.

PubMed

Poole, Kerry; Mason, Howard

2007-03-15

To establish the relationship between quantitative tests of hand function and upper limb disability, as measured by the Disability of the Arm, Shoulder and Hand (DASH) questionnaire, in hand-arm vibration syndrome (HAVS). A total of 228 individuals with HAVS were included in this study. Each had undergone a full HAVS assessment by an experienced physician, including quantitative tests of vibrotactile and thermal perception thresholds, maximal hand-grip strength (HG) and the Purdue pegboard (PP) test. Individuals were also asked to complete a DASH questionnaire. PP and HG of the quantitative tests gave the best and statistically significant individual correlations with the DASH disability score (r2 = 0.168 and 0.096). Stepwise linear regression analysis revealed that only PP and HG measurements were statistically significant predictors of upper limb disability (r2 = 0.178). Overall a combination of the PP and HG measurements, rather than each alone, gave slightly better discrimination, although not statistically significant, between normal and abnormal DASH scores with a sensitivity of 73.1% and specificity of 64.3%. Measurements of manual dexterity and hand-grip strength using PP and HG may be useful in helping to confirm lack of upper limb function and 'perceived' disability in HAVS.

Development of a 3D immersive videogame to improve arm-postural coordination in patients with TBI

PubMed Central

2011-01-01

Background Traumatic brain injury (TBI) disrupts the central and executive mechanisms of arm(s) and postural (trunk and legs) coordination. To address these issues, we developed a 3D immersive videogame-- Octopus. The game was developed using the basic principles of videogame design and previous experience of using videogames for rehabilitation of patients with acquired brain injuries. Unlike many other custom-designed virtual environments, Octopus included an actual gaming component with a system of multiple rewards, making the game challenging, competitive, motivating and fun. Effect of a short-term practice with the Octopus game on arm-postural coordination in patients with TBI was tested. Methods The game was developed using WorldViz Vizard software, integrated with the Qualysis system for motion analysis. Avatars of the participant's hands precisely reproducing the real-time kinematic patterns were synchronized with the simulated environment, presented in the first person 3D view on an 82-inch DLP screen. 13 individuals with mild-to-moderate manifestations of TBI participated in the study. While standing in front of the screen, the participants interacted with a computer-generated environment by popping bubbles blown by the Octopus. The bubbles followed a specific trajectory. Interception of the bubbles with the left or right hand avatar allowed flexible use of the postural segments for balance maintenance and arm transport. All participants practiced ten 90-s gaming trials during a single session, followed by a retention test. Arm-postural coordination was analysed using principal component analysis. Results As a result of the short-term practice, the participants improved in game performance, arm movement time, and precision. Improvements were achieved mostly by adapting efficient arm-postural coordination strategies. Of the 13 participants, 10 showed an immediate increase in arm forward reach and single-leg stance time. Conclusion These results support the

Development of a 3D immersive videogame to improve arm-postural coordination in patients with TBI.

PubMed

Ustinova, Ksenia I; Leonard, Wesley A; Cassavaugh, Nicholas D; Ingersoll, Christopher D

2011-10-31

Traumatic brain injury (TBI) disrupts the central and executive mechanisms of arm(s) and postural (trunk and legs) coordination. To address these issues, we developed a 3D immersive videogame--Octopus. The game was developed using the basic principles of videogame design and previous experience of using videogames for rehabilitation of patients with acquired brain injuries. Unlike many other custom-designed virtual environments, Octopus included an actual gaming component with a system of multiple rewards, making the game challenging, competitive, motivating and fun. Effect of a short-term practice with the Octopus game on arm-postural coordination in patients with TBI was tested. The game was developed using WorldViz Vizard software, integrated with the Qualysis system for motion analysis. Avatars of the participant's hands precisely reproducing the real-time kinematic patterns were synchronized with the simulated environment, presented in the first person 3D view on an 82-inch DLP screen. 13 individuals with mild-to-moderate manifestations of TBI participated in the study. While standing in front of the screen, the participants interacted with a computer-generated environment by popping bubbles blown by the Octopus. The bubbles followed a specific trajectory. Interception of the bubbles with the left or right hand avatar allowed flexible use of the postural segments for balance maintenance and arm transport. All participants practiced ten 90-s gaming trials during a single session, followed by a retention test. Arm-postural coordination was analysed using principal component analysis. As a result of the short-term practice, the participants improved in game performance, arm movement time, and precision. Improvements were achieved mostly by adapting efficient arm-postural coordination strategies. Of the 13 participants, 10 showed an immediate increase in arm forward reach and single-leg stance time. These results support the feasibility of using the custom-made 3D

[Aerodynamic characteristics of crewman's arms during windblast].

PubMed

Zhang, Yun-ran; Wu, Gui-rong

2003-10-01

To study the aerodynamic characteristics of crewman's arms with or without protective devices in the status with raised legs or not. The experiments were performed in an FL-24 transonic and supersonic wind tunnel, over Mach number range of 0.4-2.0, with 5 degrees-30 degrees angles of attack, 0 degrees - 90 degrees sideslip angles and Re number of (0.93-3.1) x 10(6). The test model was a 1/5-scale crewman/ejection seat combination. The aerodynamic characteristics of the various sections of crewman's arms were studied and analyzed. The results showed that 1) The effect of raised leg on the aerodynamic characteristics of the crewman's arms was very evident, and was related to the status of leg raising; 2) The sideslip considerably increased aerodynamic loads on the crewman's arms, in particular when beta=50 degrees the loads was severe in the test; 3) The tested protective devices was valid, the effectiveness of wind deflector in protecting crewman's arms was evident; 4) A formula for calculating aerodynamic force acting on crewman's arms was presented. 1)The tested protective devices was valid, and the effectiveness of wind deflector in protecting crewman's arms was evident; 2) An aerodynamic basis for the development of crewman windblast protective device was presented; 3)The calculation formula presented is useful in estimating aerodynamic forces of crewman's arms.

Exposure assessment in health assessments for hand-arm vibration syndrome.

PubMed

Mason, H J; Poole, K; Young, C

2011-08-01

Assessing past cumulative vibration exposure is part of assessing the risk of hand-arm vibration syndrome (HAVS) in workers exposed to hand-arm vibration and invariably forms part of a medical assessment of such workers. To investigate the strength of relationships between the presence and severity of HAVS and different cumulative exposure metrics obtained from a self-reporting questionnaire. Cumulative exposure metrics were constructed from a tool-based questionnaire applied in a group of HAVS referrals and workplace field studies. These metrics included simple years of vibration exposure, cumulative total hours of all tool use and differing combinations of acceleration magnitudes for specific tools and their daily use, including the current frequency-weighting method contained in ISO 5349-1:2001. Use of simple years of exposure is a weak predictor of HAVS or its increasing severity. The calculation of cumulative hours across all vibrating tools used is a more powerful predictor. More complex calculations based on involving likely acceleration data for specific classes of tools, either frequency weighted or not, did not offer a clear further advantage in this dataset. This may be due to the uncertainty associated with workers' recall of their past tool usage or the variability between tools in the magnitude of their vibration emission. Assessing years of exposure or 'latency' in a worker should be replaced by cumulative hours of tool use. This can be readily obtained using a tool-pictogram-based self-reporting questionnaire and a simple spreadsheet calculation.

Vocational Rehabilitation of Young Adults with a Disability of One Arm or Hand.

ERIC Educational Resources Information Center

Nijboer, Irene D.; Wevers, Cornelius J.

1993-01-01

A work analysis was conducted to determine whether the job of lathe and milling machine operator is suitable for young adults with one arm or hand. The analysis concluded that it is suitable but adjustments of the workplace may be necessary, such as transporting heavy equipment. The importance of labor research to vocational rehabilitation is…

Feasibility study into self-administered training at home using an arm and hand device with motivational gaming environment in chronic stroke.

PubMed

Nijenhuis, Sharon M; Prange, Gerdienke B; Amirabdollahian, Farshid; Sale, Patrizio; Infarinato, Francesco; Nasr, Nasrin; Mountain, Gail; Hermens, Hermie J; Stienen, Arno H A; Buurke, Jaap H; Rietman, Johan S

2015-10-09

Assistive and robotic training devices are increasingly used for rehabilitation of the hemiparetic arm after stroke, although applications for the wrist and hand are trailing behind. Furthermore, applying a training device in domestic settings may enable an increased training dose of functional arm and hand training. The objective of this study was to assess the feasibility and potential clinical changes associated with a technology-supported arm and hand training system at home for patients with chronic stroke. A dynamic wrist and hand orthosis was combined with a remotely monitored user interface with motivational gaming environment for self-administered training at home. Twenty-four chronic stroke patients with impaired arm/hand function were recruited to use the training system at home for six weeks. Evaluation of feasibility involved training duration, usability and motivation. Clinical outcomes on arm/hand function, activity and participation were assessed before and after six weeks of training and at two-month follow-up. Mean System Usability Scale score was 69 % (SD 17 %), mean Intrinsic Motivation Inventory score was 5.2 (SD 0.9) points, and mean training duration per week was 105 (SD 66) minutes. Median Fugl-Meyer score improved from 37 (IQR 30) pre-training to 41 (IQR 32) post-training and was sustained at two-month follow-up (40 (IQR 32)). The Stroke Impact Scale improved from 56.3 (SD 13.2) pre-training to 60.0 (SD 13.9) post-training, with a trend at follow-up (59.8 (SD 15.2)). No significant improvements were found on the Action Research Arm Test and Motor Activity Log. Remotely monitored post-stroke training at home applying gaming exercises while physically supporting the wrist and hand showed to be feasible: participants were able and motivated to use the training system independently at home. Usability shows potential, although several usability issues need further attention. Upper extremity function and quality of life improved after training

Bruising Hands and Arms

MedlinePlus

... arms is common. Dermatologists call it 'actinic purpura', 'solar purpura' or 'Bateman's purpura'. These flat blotches start ... lesion or disease, please consult a dermatologist. Any use, re-creation, dissemination, forwarding or copying of this ...

The validity and clinical utility of the Disabilities of the Arm Shoulder and Hand questionnaire for hand injuries in developing country contexts: A systematic review.

PubMed

de Klerk, Susan; Buchanan, Helen; Jerosch-Herold, Christina

Systematic review. The Disabilities of the Arm Shoulder and Hand Questionnaire has multiple language versions from many countries around the world. In addition there is extensive research evidence of its psychometric properties. The purpose of this study was to systematically review the evidence available on the validity and clinical utility of the Disabilities of the Arm Shoulder and Hand as a measure of activity and participation in patients with musculoskeletal hand injuries in developing country contexts. We registered the review with international prospective register of systematic reviews prior to conducting a comprehensive literature search and extracting descriptive data. Two reviewers independently assessed methodological quality with the Consensus-Based Standards for the Selection of Health Measurement Instruments critical appraisal tool, the checklist to operationalize measurement characteristics of patient-rated outcome measures and the multidimensional model of clinical utility. Fourteen studies reporting 12 language versions met the eligibility criteria. Two language versions (Persian and Turkish) had an overall rating of good, and one (Thai) had an overall rating of excellent for cross-cultural validity. The remaining 9 language versions had an overall poor rating for cross-cultural validity. Content and construct validity and clinical utility yielded similar results. Poor quality ratings for validity and clinical utility were due to insufficient documentation of results and inadequate psychometric testing. With the increase in migration and globalization, hand therapists are likely to require a range of culturally adapted and translated versions of the Disabilities of the Arm Shoulder and Hand. Recommendations include rigorous application and reporting of cross-cultural adaptation, appropriate psychometric testing, and testing of clinical utility in routine clinical practice. Copyright © 2017 Hanley & Belfus. Published by Elsevier Inc. All rights

Current Perception Threshold for Assessment of the Neurological Components of Hand-Arm Vibration Syndrome: A Review

PubMed Central

Kurozawa, Youichi; Hosoda, Takenobu; Nasu, Yoshiro

2010-01-01

Current perception threshold (CPT) has been proposed as a quantitative method for assessment of peripheral sensory nerve function. The aim of this review of selected reports is to provide an overview of CPT measurement for the assessment of the neurological component of hand-arm vibration syndrome (HAVS). The CPT values at 2000 Hz significantly increased for patients with HAVS. This result supports the previous histological findings that demyelination is found predominantly in the peripheral nerves in the hands of men exposed to hand-arm vibration. Diagnostic sensitivity and specificity were high for severe cases of Stockholm sensorineural (SSN) stage 3 compared with non-exposed controls, but not high for mild cases of SSN stage 1 or 2 and for carpal tunnel syndrome associated with HAVS. However, there are only a few studies on the diagnostic validity of the CPT test for the neurological components of HAVS. Further research is needed and should include diagnostic validity and standardizing of measurement conditions such as skin temperature. PMID:24031119

Frequency weighting derived from power absorption of fingers-hand-arm system under z(h)-axis vibration.

PubMed

Dong, Ren G; Welcome, Daniel E; McDowell, Thomas W; Wu, John Z; Schopper, Aaron W

2006-01-01

The objectives of this study are to derive the frequency weighting from three vibration power absorption (VPA) methods (finger VPA, palm VPA, and total or hand VPA), and to explore whether these energy methods are better than the currently accepted acceleration method. To calculate the VPA weightings, the mechanical impedance of eight subjects exposed to a broadband random vibration spectrum in the z(h)-axis using 18 combinations of hand couplings and applied forces was measured. The VPA weightings were compared with the frequency weighting specified in ISO 5349-1 [2001. Mechanical Vibration--Measurement and Evaluation of Human Exposure to Hand--Transmitted Vibration--Part 1: General Requirements. International Organization for Standardization, Geneva, Switzerland]. This study found that the hand and palm VPA weightings are very similar to the ISO weighting but the finger VPA weighting for the combined grip and push action is much higher than the ISO weighting at frequencies higher than 25 Hz. Therefore, this study predicted that the total power absorption of the entire hand-arm system is likely to be correlated with psychophysical response or subjective sensation. However, if the ISO weighting method cannot yield good predictions of the vibration-induced disorders in the fingers and hand, the hand and palm energy methods are unlikely to yield significantly better predictions. The finger VPA is a vibration measure between unweighted and ISO weighted accelerations. The palm VPA method may have some value for studying the disorders in the wrist-arm system.

Improved accuracy of screw implantation could decrease the incidence of post-operative hydrothorax? O-arm navigation vs. free-hand in thoracic spinal deformity correction surgery.

PubMed

Zhao, Zhihui; Liu, Zhen; Hu, Zongshan; Tseng, Changchun; Li, Jie; Pan, Wei; Qiu, Yong; Zhu, Zezhang

2018-03-16

The purpose of this study was to analyze the occurrence of PE after intra-operative O-arm navigation-assisted surgery and determine whether the post-operative PE incidence could be decreased by using O-arm navigation as compared to conventional free-hand technique. A cohort of 27 patients with spinal deformity who were operated upon with an O-arm navigated system (group A) between 2013 and 2016 were enrolled in the study. A total of 27 curve-matched patients treated by conventional free-hand technique were included as the control group (group B). Whole spine posterior-anterior and lateral radiographs, and CT scans were taken pre and post-operation. Radiologic parameters and volume of PE were measured and compared between the two groups. There were no significant differences in age, Cobb angle, and sagittal contour between the two groups pre-operatively. The mean total volume of post-operative PE was significantly larger in the free-hand group (p < 0.001). In the O-arm group, 59 malpositioned screws were identified in 22 patients. In the free-hand group, 88 malpositioned screws were found among 26 patients. The screw perforation rate was higher in the free-hand group than in the O-arm group (p = 0.007). In the O-arm group, the mean volume of PE was significantly larger among patients with malpositioned screws than those without malpositioned screws (p < 0.001), as well as in the free-hand group. The volume of PE after correction surgery can be significantly decreased by application of O-arm navigation system as compared to conventional free-hand technique. We ascribed the improvement to the accuracy of screw implantation navigated by O-arm.

Effective Propulsion in Swimming: Grasping the Hydrodynamics of Hand and Arm Movements.

PubMed

van Houwelingen, Josje; Schreven, Sander; Smeets, Jeroen B J; Clercx, Herman J H; Beek, Peter J

2017-02-01

In this paper, a literature review is presented regarding the hydrodynamic effects of different hand and arm movements during swimming with the aim to identify lacunae in current methods and knowledge, and to distil practical guidelines for coaches and swimmers seeking to increase swimming speed. Experimental and numerical studies are discussed, examining the effects of hand orientation, thumb position, finger spread, sculling movements, and hand accelerations during swimming, as well as unsteady properties of vortices due to changes in hand orientation. Collectively, the findings indicate that swimming speed may be increased by avoiding excessive sculling movements and by spreading the fingers slightly. In addition, it appears that accelerating the hands rather than moving them at constant speed may be beneficial, and that (in front crawl swimming) the thumb should be abducted during entry, catch, and upsweep, and adducted during the pull phase. Further experimental and numerical research is required to confirm these suggestions and to elucidate their hydrodynamic underpinnings and identify optimal propulsion techniques. To this end, it is necessary that the dynamical motion and resulting unsteady effects are accounted for, and that flow visualization techniques, force measurements, and simulations are combined in studying those effects.

Dissociable neural responses to hands and non-hand body parts in human left extrastriate visual cortex.

PubMed

Bracci, Stefania; Ietswaart, Magdalena; Peelen, Marius V; Cavina-Pratesi, Cristiana

2010-06-01

Accumulating evidence points to a map of visual regions encoding specific categories of objects. For example, a region in the human extrastriate visual cortex, the extrastriate body area (EBA), has been implicated in the visual processing of bodies and body parts. Although in the monkey, neurons selective for hands have been reported, in humans it is unclear whether areas selective for individual body parts such as the hand exist. Here, we conducted two functional MRI experiments to test for hand-preferring responses in the human extrastriate visual cortex. We found evidence for a hand-preferring region in left lateral occipitotemporal cortex in all 14 participants. This region, located in the lateral occipital sulcus, partially overlapped with left EBA, but could be functionally and anatomically dissociated from it. In experiment 2, we further investigated the functional profile of hand- and body-preferring regions by measuring responses to hands, fingers, feet, assorted body parts (arms, legs, torsos), and non-biological handlike stimuli such as robotic hands. The hand-preferring region responded most strongly to hands, followed by robotic hands, fingers, and feet, whereas its response to assorted body parts did not significantly differ from baseline. By contrast, EBA responded most strongly to body parts, followed by hands and feet, and did not significantly respond to robotic hands or fingers. Together, these results provide evidence for a representation of the hand in extrastriate visual cortex that is distinct from the representation of other body parts.

Dissociable Neural Responses to Hands and Non-Hand Body Parts in Human Left Extrastriate Visual Cortex

PubMed Central

Ietswaart, Magdalena; Peelen, Marius V.; Cavina-Pratesi, Cristiana

2010-01-01

Accumulating evidence points to a map of visual regions encoding specific categories of objects. For example, a region in the human extrastriate visual cortex, the extrastriate body area (EBA), has been implicated in the visual processing of bodies and body parts. Although in the monkey, neurons selective for hands have been reported, in humans it is unclear whether areas selective for individual body parts such as the hand exist. Here, we conducted two functional MRI experiments to test for hand-preferring responses in the human extrastriate visual cortex. We found evidence for a hand-preferring region in left lateral occipitotemporal cortex in all 14 participants. This region, located in the lateral occipital sulcus, partially overlapped with left EBA, but could be functionally and anatomically dissociated from it. In experiment 2, we further investigated the functional profile of hand- and body-preferring regions by measuring responses to hands, fingers, feet, assorted body parts (arms, legs, torsos), and non-biological handlike stimuli such as robotic hands. The hand-preferring region responded most strongly to hands, followed by robotic hands, fingers, and feet, whereas its response to assorted body parts did not significantly differ from baseline. By contrast, EBA responded most strongly to body parts, followed by hands and feet, and did not significantly respond to robotic hands or fingers. Together, these results provide evidence for a representation of the hand in extrastriate visual cortex that is distinct from the representation of other body parts. PMID:20393066

Thermal Energy Harvesting on the Bodily Surfaces of Arms and Legs through a Wearable Thermo-Electric Generator.

PubMed

Proto, Antonino; Bibbo, Daniele; Cerny, Martin; Vala, David; Kasik, Vladimir; Peter, Lukas; Conforto, Silvia; Schmid, Maurizio; Penhaker, Marek

2018-06-13

This work analyzes the results of measurements on thermal energy harvesting through a wearable Thermo-electric Generator (TEG) placed on the arms and legs. Four large skin areas were chosen as locations for the placement of the TEGs. In order to place the generator on the body, a special manufactured band guaranteed the proper contact between the skin and TEG. Preliminary measurements were performed to find out the value of the resistor load which maximizes the power output. Then, an experimental investigation was conducted for the measurement of harvested energy while users were performing daily activities, such as sitting, walking, jogging, and riding a bike. The generated power values were in the range from 5 to 50 μW. Moreover, a preliminary hypothesis based on the obtained results indicates the possibility to use TEGs on leg for the recognition of locomotion activities. It is due to the rather high and different biomechanical work, produced by the gastrocnemius muscle, while the user is walking rather than jogging or riding a bike. This result reflects a difference between temperatures associated with the performance of different activities.

Human-Human Interaction Forces and Interlimb Coordination During Side-by-Side Walking With Hand Contact.

PubMed

Sylos-Labini, Francesca; d'Avella, Andrea; Lacquaniti, Francesco; Ivanenko, Yury

2018-01-01

Handholding can naturally occur between two walkers. When people walk side-by-side, either with or without hand contact, they often synchronize their steps. However, despite the importance of haptic interaction in general and the natural use of hand contact between humans during walking, few studies have investigated forces arising from physical interactions. Eight pairs of adult subjects participated in this study. They walked on side-by-side treadmills at 4 km/h independently and with hand contact. Only hand contact-related sensory information was available for unintentional synchronization, while visual and auditory communication was obstructed. Subjects walked at their natural cadences or following a metronome. Limb kinematics, hand contact 3D interaction forces and EMG activity of 12 upper limb muscles were recorded. Overall, unintentional step frequency locking was observed during about 40% of time in 88% of pairs walking with hand contact. On average, the amplitude of contact arm oscillations decreased while the contralateral (free) arm oscillated in the same way as during normal walking. Interestingly, EMG activity of the shoulder muscles of the contact arm did not decrease, and their synergistic pattern remained similar. The amplitude of interaction forces and of trunk oscillations was similar for synchronized and non-synchronized steps, though the synchronized steps were characterized by significantly more regular orientations of interaction forces. Our results further support the notion that gait synchronization during natural walking is common, and that it may occur through interaction forces. Conservation of the proximal muscle activity of the contact (not oscillating) arm is consistent with neural coupling between cervical and lumbosacral pattern generation circuitries ("quadrupedal" arm-leg coordination) during human gait. Overall, the findings suggest that individuals might integrate force interaction cues to communicate and coordinate steps during

Human-Human Interaction Forces and Interlimb Coordination During Side-by-Side Walking With Hand Contact

PubMed Central

Sylos-Labini, Francesca; d'Avella, Andrea; Lacquaniti, Francesco; Ivanenko, Yury

2018-01-01

Handholding can naturally occur between two walkers. When people walk side-by-side, either with or without hand contact, they often synchronize their steps. However, despite the importance of haptic interaction in general and the natural use of hand contact between humans during walking, few studies have investigated forces arising from physical interactions. Eight pairs of adult subjects participated in this study. They walked on side-by-side treadmills at 4 km/h independently and with hand contact. Only hand contact-related sensory information was available for unintentional synchronization, while visual and auditory communication was obstructed. Subjects walked at their natural cadences or following a metronome. Limb kinematics, hand contact 3D interaction forces and EMG activity of 12 upper limb muscles were recorded. Overall, unintentional step frequency locking was observed during about 40% of time in 88% of pairs walking with hand contact. On average, the amplitude of contact arm oscillations decreased while the contralateral (free) arm oscillated in the same way as during normal walking. Interestingly, EMG activity of the shoulder muscles of the contact arm did not decrease, and their synergistic pattern remained similar. The amplitude of interaction forces and of trunk oscillations was similar for synchronized and non-synchronized steps, though the synchronized steps were characterized by significantly more regular orientations of interaction forces. Our results further support the notion that gait synchronization during natural walking is common, and that it may occur through interaction forces. Conservation of the proximal muscle activity of the contact (not oscillating) arm is consistent with neural coupling between cervical and lumbosacral pattern generation circuitries (“quadrupedal” arm-leg coordination) during human gait. Overall, the findings suggest that individuals might integrate force interaction cues to communicate and coordinate steps

A method for analyzing absorbed power distribution in the hand and arm substructures when operating vibrating tools

NASA Astrophysics Data System (ADS)

Dong, Jennie H.; Dong, Ren G.; Rakheja, Subhash; Welcome, Daniel E.; McDowell, Thomas W.; Wu, John Z.

2008-04-01

In this study it was hypothesized that the vibration-induced injuries or disorders in a substructure of human hand-arm system are primarily associated with the vibration power absorption distributed in that substructure. As the first step to test this hypothesis, the major objective of this study is to develop a method for analyzing the vibration power flow and the distribution of vibration power absorptions in the major substructures (fingers, palm-hand-wrist, forearm and upper arm, and shoulder) of the system exposed to hand-transmitted vibration. A five-degrees-of-freedom model of the system incorporating finger- as well as palm-side driving points was applied for the analysis. The mechanical impedance data measured at the two driving points under four different hand actions involving 50 N grip-only, 15 N grip and 35 N push, 30 N grip and 45 N push, and 50 N grip and 50 N push, were used to identify the model parameters. The vibration power absorption distributed in the substructures were evaluated using vibration spectra measured on many tools. The frequency weightings of the distributed vibration power absorptions were derived and compared with the weighting defined in ISO 5349-1 (2001). This study found that vibration power absorption is primarily distributed in the arm and shoulder when operating low-frequency tools such as rammers, while a high concentration of vibration power absorption in the fingers and hand is observed when operating high-frequency tools, such as grinders. The vibration power absorption distributed in palm-wrist and arm is well correlated with the ISO-weighted acceleration, while the finger vibration power absorption is highly correlated with unweighted acceleration. The finger vibration power absorption-based frequency weighting suggested that exposure to vibration in the frequency range of 16-500 Hz could pose higher risks of developing finger disorders. The results support the use of the frequency weighting specified in the current

Comparison between free-hand and O-arm-based navigated posterior lumbar interbody fusion in elderly cohorts with three-level lumbar degenerative disease.

PubMed

Wang, Yucheng; Chen, Kangwu; Chen, Hao; Zhang, Kai; Lu, Jian; Mao, Haiqing; Yang, Huilin

2018-06-06

This retrospective cohort study aims to evaluate the effects of introducing the O-arm-based navigation technique into the traditional posterior lumbar interbody fusion (PLIF) procedure treating elderly patients with three-level lumbar degenerative diseases. Forty-one consecutive elderly patients were enrolled according to the criteria. There were 21 patients in the free-hand group and 20 patients in the O-arm group. Both two groups underwent the PLIF with or without the O-arm-based navigation technique. The demographic features, clinical data and outcomes, and radiological information were collected for further analysis. The average follow-up time was 18.3 (range, 12-28) months in the free-hand group and 16.7 (range, 12-24) months in the O-arm group. Comparison between two groups revealed no significant difference regarding demographic features. The operation time took in the navigation group was significantly less than that in the free-hand group (222.55 ± 38.00 mins versus 255.19 ± 40.26 mins, P < 0.05). Both VAS and ODI were improved post-operatively in two groups while comparison between groups showed no difference. The accuracy rate of pedicle screw positioning was 88.7% in the free-hand group to 96.9% in the O-arm group (P < 0.05). The O-arm-based navigation is an efficacious auxiliary technique which could significantly improve the accuracy of pedicle screw insertion, especially in cases of patients with complex anatomic degenerative diseases, without sacrificing the feasibility and reliable outcome of traditional PLIF.

Quantification of muscle oxygenation and flow of healthy volunteers during cuff occlusion of arm and leg flexor muscles and plantar flexion exercise

NASA Astrophysics Data System (ADS)

Durduran, Turgut; Yu, Guoqiang; Zhou, Chao; Lech, Gwen; Chance, Britton; Yodh, Arjun G.

2003-07-01

A hybrid instrument combining near infrared and diffuse correlation spectroscopies was used to measure muscle oxygenation and blood flow dynamics during cuff occlusion and ischemia. Measurements were done on six healthy subjects on their arm and leg flexor muscles. Hemodynamic response was characterized for blood oxygen saturation, total hemoglobin concenration and relative blood flow speed. The characterization allowed us to define the normal response range as well as showing the feasibility of using a hybrid instrument for dynamic measurements.

Dose-response relationship between hand-transmitted vibration and hand-arm vibration syndrome in a tropical environment.

PubMed

Su, Anselm Ting; Maeda, Setsuo; Fukumoto, Jin; Darus, Azlan; Hoe, Victor C W; Miyai, Nobuyuki; Isahak, Marzuki; Takemura, Shigeki; Bulgiba, Awang; Yoshimasu, Kouichi; Miyashita, Kazuhisa

2013-07-01

The dose-response relationship for hand-transmitted vibration has been investigated extensively in temperate environments. Since the clinical features of hand-arm vibration syndrome (HAVS) differ between the temperate and tropical environment, we conducted this study to investigate the dose-response relationship of HAVS in a tropical environment. A total of 173 male construction, forestry and automobile manufacturing plant workers in Malaysia were recruited into this study between August 2011 and 2012. The participants were interviewed for history of vibration exposure and HAVS symptoms, followed by hand functions evaluation and vibration measurement. Three types of vibration doses-lifetime vibration dose (LVD), total operating time (TOT) and cumulative exposure index (CEI)-were calculated and its log values were regressed against the symptoms of HAVS. The correlation between each vibration exposure dose and the hand function evaluation results was obtained. The adjusted prevalence ratio for finger tingling and numbness was 3.34 (95% CI 1.27 to 8.98) for subjects with lnLVD≥20 ln m(2) s(-4) against those <16 ln m(2) s(-4). Similar dose-response pattern was found for CEI but not for TOT. No subject reported white finger. The prevalence of finger coldness did not increase with any of the vibration doses. Vibrotactile perception thresholds correlated moderately with lnLVD and lnCEI. The dose-response relationship of HAVS in a tropical environment is valid for finger tingling and numbness. The LVD and CEI are more useful than TOT when evaluating the dose-response pattern of a heterogeneous group of vibratory tools workers.

Representation of continuous hand and arm movements in macaque areas M1, F5, and AIP: a comparative decoding study

NASA Astrophysics Data System (ADS)

Menz, Veera Katharina; Schaffelhofer, Stefan; Scherberger, Hansjörg

2015-10-01

Objective. In the last decade, multiple brain areas have been investigated with respect to their decoding capability of continuous arm or hand movements. So far, these studies have mainly focused on motor or premotor areas like M1 and F5. However, there is accumulating evidence that anterior intraparietal area (AIP) in the parietal cortex also contains information about continuous movement. Approach. In this study, we decoded 27 degrees of freedom representing complete hand and arm kinematics during a delayed grasping task from simultaneously recorded activity in areas M1, F5, and AIP of two macaque monkeys (Macaca mulatta). Main results. We found that all three areas provided decoding performances that lay significantly above chance. In particular, M1 yielded highest decoding accuracy followed by F5 and AIP. Furthermore, we provide support for the notion that AIP does not only code categorical visual features of objects to be grasped, but also contains a substantial amount of temporal kinematic information. Significance. This fact could be utilized in future developments of neural interfaces restoring hand and arm movements.

An artificial arm/hand system with a haptic sensory function using electric stimulation of peripheral sensory nerve fibers.

PubMed

Mabuchi, Kunihiko

2013-01-01

We are currently developing an artificial arm/hand system which is capable of sensing stimuli and then transferring these stimuli to users as somatic sensations. Presently, we are evoking the virtual somatic sensations by electrically stimulating a sensory nerve fiber which innervates a single mechanoreceptor unit at the target area; this is done using a tungsten microelectrode that was percutaneously inserted into the use's peripheral nerve (a microstimulation method). The artificial arm/hand system is composed of a robot hand equipped with a pressure sensor system on its fingers. The sensor system detects mechanical stimuli, which are transferred to the user by means of the microstimulation method so that the user experiences the stimuli as the corresponding somatic sensations. In trials, the system worked satisfactorily and there was a good correlation between the pressure applied to the pressure sensors on the robot fingers and the subjective intensities of the evoked pressure sensations.

Control of Leg Movements Driven by EMG Activity of Shoulder Muscles

PubMed Central

La Scaleia, Valentina; Sylos-Labini, Francesca; Hoellinger, Thomas; Wang, Letian; Cheron, Guy; Lacquaniti, Francesco; Ivanenko, Yuri P.

2014-01-01

During human walking, there exists a functional neural coupling between arms and legs, and between cervical and lumbosacral pattern generators. Here, we present a novel approach for associating the electromyographic (EMG) activity from upper limb muscles with leg kinematics. Our methodology takes advantage of the high involvement of shoulder muscles in most locomotor-related movements and of the natural co-ordination between arms and legs. Nine healthy subjects were asked to walk at different constant and variable speeds (3–5 km/h), while EMG activity of shoulder (deltoid) muscles and the kinematics of walking were recorded. To ensure a high level of EMG activity in deltoid, the subjects performed slightly larger arm swinging than they usually do. The temporal structure of the burst-like EMG activity was used to predict the spatiotemporal kinematic pattern of the forthcoming step. A comparison of actual and predicted stride leg kinematics showed a high degree of correspondence (r > 0.9). This algorithm has been also implemented in pilot experiments for controlling avatar walking in a virtual reality setup and an exoskeleton during over-ground stepping. The proposed approach may have important implications for the design of human–machine interfaces and neuroprosthetic technologies such as those of assistive lower limb exoskeletons. PMID:25368569

Control of Leg Movements Driven by EMG Activity of Shoulder Muscles.

PubMed

La Scaleia, Valentina; Sylos-Labini, Francesca; Hoellinger, Thomas; Wang, Letian; Cheron, Guy; Lacquaniti, Francesco; Ivanenko, Yuri P

2014-01-01

During human walking, there exists a functional neural coupling between arms and legs, and between cervical and lumbosacral pattern generators. Here, we present a novel approach for associating the electromyographic (EMG) activity from upper limb muscles with leg kinematics. Our methodology takes advantage of the high involvement of shoulder muscles in most locomotor-related movements and of the natural co-ordination between arms and legs. Nine healthy subjects were asked to walk at different constant and variable speeds (3-5 km/h), while EMG activity of shoulder (deltoid) muscles and the kinematics of walking were recorded. To ensure a high level of EMG activity in deltoid, the subjects performed slightly larger arm swinging than they usually do. The temporal structure of the burst-like EMG activity was used to predict the spatiotemporal kinematic pattern of the forthcoming step. A comparison of actual and predicted stride leg kinematics showed a high degree of correspondence (r > 0.9). This algorithm has been also implemented in pilot experiments for controlling avatar walking in a virtual reality setup and an exoskeleton during over-ground stepping. The proposed approach may have important implications for the design of human-machine interfaces and neuroprosthetic technologies such as those of assistive lower limb exoskeletons.

Characterizing rapid-onset vasodilation to single muscle contractions in the human leg

PubMed Central

Credeur, Daniel P.; Holwerda, Seth W.; Restaino, Robert M.; King, Phillip M.; Crutcher, Kiera L.; Laughlin, M. Harold; Padilla, Jaume

2014-01-01

Rapid-onset vasodilation (ROV) following single muscle contractions has been examined in the forearm of humans, but has not yet been characterized in the leg. Given known vascular differences between the arm and leg, we sought to characterize ROV following single muscle contractions in the leg. Sixteen healthy men performed random ordered single contractions at 5, 10, 20, 40, and 60% of their maximum voluntary contraction (MVC) using isometric knee extension made with the leg above and below heart level, and these were compared with single isometric contractions of the forearm (handgrip). Single thigh cuff compressions (300 mmHg) were utilized to estimate the mechanical contribution to leg ROV. Continuous blood flow was determined by duplex-Doppler ultrasound and blood pressure via finger photoplethysmography (Finometer). Single isometric knee extensor contractions produced intensity-dependent increases in peak leg vascular conductance that were significantly greater than the forearm in both the above- and below-heart level positions (e.g., above heart level: leg 20% MVC, +138 ± 28% vs. arm 20% MVC, +89 ± 17%; P < 0.05). Thigh cuff compressions also produced a significant hyperemic response, but these were brief and smaller in magnitude compared with single isometric contractions in the leg. Collectively, these data demonstrate the presence of a rapid and robust vasodilation to single muscle contractions in the leg that is largely independent of mechanical factors, thus establishing the leg as a viable model to study ROV in humans. PMID:25539935

49 CFR 572.15 - General description.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Assembly SA 103C 030 Torso Assembly SA 103C 041 Upper Arm Assembly Left SA 103C 042 Upper Arm Assembly Right SA 103C 051 Forearm Hand Assembly Left SA 103C 052 Forearm Hand Assembly Right SA 103C 061Upper Leg Assembly Left SA 103C 062 Upper Leg Assembly Right SA 103C 071 Lower Leg Assembly Left SA 103C 072...

49 CFR 572.15 - General description.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Assembly SA 103C 030 Torso Assembly SA 103C 041 Upper Arm Assembly Left SA 103C 042 Upper Arm Assembly Right SA 103C 051 Forearm Hand Assembly Left SA 103C 052 Forearm Hand Assembly Right SA 103C 061Upper Leg Assembly Left SA 103C 062 Upper Leg Assembly Right SA 103C 071 Lower Leg Assembly Left SA 103C 072...

49 CFR 572.15 - General description.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Assembly SA 103C 030 Torso Assembly SA 103C 041 Upper Arm Assembly Left SA 103C 042 Upper Arm Assembly Right SA 103C 051 Forearm Hand Assembly Left SA 103C 052 Forearm Hand Assembly Right SA 103C 061Upper Leg Assembly Left SA 103C 062 Upper Leg Assembly Right SA 103C 071 Lower Leg Assembly Left SA 103C 072...

49 CFR 572.15 - General description.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Assembly SA 103C 030 Torso Assembly SA 103C 041 Upper Arm Assembly Left SA 103C 042 Upper Arm Assembly Right SA 103C 051 Forearm Hand Assembly Left SA 103C 052 Forearm Hand Assembly Right SA 103C 061Upper Leg Assembly Left SA 103C 062 Upper Leg Assembly Right SA 103C 071 Lower Leg Assembly Left SA 103C 072...

Isometric Arm Strength and Subjective Rating of Upper Limb Fatigue in Two-Handed Carrying Tasks

PubMed Central

Li, Kai Way; Chiu, Wen-Sheng

2015-01-01

Sustained carrying could result in muscular fatigue of the upper limb. Ten male and ten female subjects were recruited for measurements of isometric arm strength before and during carrying a load for a period of 4 minutes. Two levels of load of carrying were tested for each of the male and female subjects. Exponential function based predictive equations for the isometric arm strength were established. The mean absolute deviations of these models in predicting the isometric arm strength were in the range of 3.24 to 17.34 N. Regression analyses between the subjective ratings of upper limb fatigue and force change index (FCI) for the carrying were also performed. The results indicated that the subjective rating of muscular fatigue may be estimated by multiplying the FCI with a constant. The FCI may, therefore, be adopted as an index to assess muscular fatigue for two-handed carrying tasks. PMID:25794159

Isometric arm strength and subjective rating of upper limb fatigue in two-handed carrying tasks.

PubMed

Li, Kai Way; Chiu, Wen-Sheng

2015-01-01

Sustained carrying could result in muscular fatigue of the upper limb. Ten male and ten female subjects were recruited for measurements of isometric arm strength before and during carrying a load for a period of 4 minutes. Two levels of load of carrying were tested for each of the male and female subjects. Exponential function based predictive equations for the isometric arm strength were established. The mean absolute deviations of these models in predicting the isometric arm strength were in the range of 3.24 to 17.34 N. Regression analyses between the subjective ratings of upper limb fatigue and force change index (FCI) for the carrying were also performed. The results indicated that the subjective rating of muscular fatigue may be estimated by multiplying the FCI with a constant. The FCI may, therefore, be adopted as an index to assess muscular fatigue for two-handed carrying tasks.

Tremor and hand-arm vibration syndrome (HAVS) in road maintenance workers.

PubMed

Bast-Pettersen, Rita; Ulvestad, Bente; Færden, Karl; Clemm, Thomas Aleksander C; Olsen, Raymond; Ellingsen, Dag Gunnar; Nordby, Karl-Christian

2017-01-01

The aim of this study was to evaluate postural and rest tremor among workers using vibrating hand tools, taking into account the possible effects of toxicants such as alcohol and tobacco. A further aim was to study workers diagnosed with hand-arm vibration syndrome (HAVS) at the time of examination. This study comprises 103 road maintenance workers, 55 exposed to vibrating hand tools (age 41.0 years; range 21-62) and 48 referents (age 38.5 years; range 19-64). They were examined with the CATSYS Tremor Pen ® . Exposure to vibrating tools and serum biomarkers of alcohol and tobacco consumption were measured. Cumulative exposure to vibrating tools was associated with increased postural (p < 0.01) and rest tremor (p < 0.05) and with a higher Center Frequency of postural tremor (p < 0.01) among smokers and users of smokeless tobacco. Rest tremor Center Frequency was higher than postural tremor frequency (p < 0.001). The main findings indicate an association between cumulative exposure to hand-held vibrating tools, tremor parameters and consumption of tobacco products. The hand position is important when testing for tremor. Rest tremor had a higher Center Frequency. Postural tremor was more strongly associated with exposure than rest tremor. The finding of increased tremor among the HAVS subjects indicated that tremor might be a part of the clinical picture of a HAVS diagnosis. As with all cross-sectional studies, inferences should be made with caution when drawing conclusions about associations between exposure and possible effects. Future research using longitudinal design is required to validate the findings of the present study.

Hand-arm vibration in tropical rain forestry workers.

PubMed

Futatsuka, M; Inaoka, T; Ohtsuka, R; Sakurai, T; Moji, K; Igarashi, T

1995-01-01

Working conditions and health hazards including vibration syndrome related to forestry work using chain-saws were studied in Papua New Guinea and Indonesia. The subjects comprised 291 workers including 97 chain-saw operators. The health examination consisted of peripheral circulatory and sensory tests in the upper extremities. The vibration spectrum measured at the handle of the chain-saw indicated that these acceleration levels would lead to a moderately high risk of hand-arm vibration syndrome (HAVS). The peripheral circulatory function tests revealed dysfunction after more than five years vibration exposure. However, in general, the results of the function tests and subjective complaints showed fewer health problems compared to those of Japanese forestry workers. The reason of such differences of vibration effects seem to be the following: (1) warmer climate (more than 25 degrees C throughout the year), (2) young workers and short work experience. (3) short time vibration exposures on working days in the natural forests, (4) seasonal changes in logging work (5) healthy workers effects. Thus, we found no clear evidence that the workers of our study suffered from HAVS. A principal component analysis was applied. The factor score of the components of the reactive dynamics of peripheral circulation differed significantly after more than five years' exposure. On the other hand, we cannot deny the possibility that subclinical dysfunction of peripheral circulation may be caused by chain-saw operation in the tropics in future. Further investigations on the HAVS among forestry workers in the tropic environment are needed.

Computer coordination of limb motion for a three-legged walking robot

NASA Technical Reports Server (NTRS)

Klein, C. A.; Patterson, M. R.

1980-01-01

Coordination of the limb motion of a vehicle which could perform assembly and maintenance operations on large structures in space is described. Manipulator kinematics and walking robots are described. The basic control scheme of the robot is described. The control of the individual arms are described. Arm velocities are generally described in Cartesian coordinates. Cartesian velocities are converted to joint velocities using the Jacobian matrix. The calculation of a trajectory for an arm given a sequence of points through which it is to pass is described. The free gait algorithm which controls the lifting and placing of legs for the robot is described. The generation of commanded velocities for the robot, and the implementation of those velocities by the algorithm are discussed. Suggestions for further work in the area of robot legged locomotion are presented.

Disability in the upper extremity and quality of life in hand-arm vibration syndrome.

PubMed

Poole, Kerry; Mason, Howard

2005-11-30

To investigate whether hand-arm vibration syndrome (HAVS) leads to disability in the upper extremity or deficit in quality of life (QoL) using validated questionnaire tools, and to establish whether these effects are related to the Stockholm Workshop Staging (SWS). This was a postal cross-sectional questionnaire study with a 50% response rate. Four hundred and forty-four males, who had been diagnosed and staged according to the SWS were sent the Disability in the Arm, Shoulder and Hand (DASH) and the SF-36v2 QoL questionnaires. HAVS cases had significantly greater DASH disability scores and reduced QoL physical and mental component scores compared to published normal values. Those HAVS cases with a presumptive diagnosis of Carpal Tunnel Syndrome(CTS) had even higher disability scores. There was a clear, linear relationship between both the DASH disability score and the physical component of the QoL and sensorineural SWS, but not with the vascular SWS. HAVS has a significant effect on an individual's perceived ability to perform everyday tasks involving the upper extremity, and their quality of life. Physical capability may be further compromised in those individuals who have a presumptive diagnosis of CTS. These findings may have important implications regarding management of the affected worker.

Hand-arm vibration syndrome among a group of construction workers in Malaysia.

PubMed

Su, Ting Anselm; Hoe, Victor Chee Wai; Masilamani, Retneswari; Awang Mahmud, Awang Bulgiba

2011-01-01

To determine the extent of hand transmitted vibration exposure problems, particularly hand-arm vibration syndrome (HAVS), among construction workers in Malaysia. A cross-sectional study was conducted on a construction site in Kuala Lumpur, Malaysia. 243 workers were recruited. Questionnaire interviews and hand examinations were administered to 194 respondents. Vibration magnitudes for concrete breakers, drills and grinders were measured using a 3-axis accelerometer. Clinical outcomes were compared and analysed according to vibration exposure status. Vibration total values for concrete breakers, impact drills and grinders were 10.02 ms(-2), 7.72 ms(-2) and 5.29ms(-2), respectively. The mean 8 h time-weighted hand transmitted vibration exposure, A(8), among subjects on current and previous construction sites was 7.52 (SD 2.68) ms(-2) and 9.21 (SD 2.48) ms(-2), respectively. Finger tingling, finger numbness, musculoskeletal problems of the neck, finger coldness, abnormal Phalen's test and abnormal light touch sensation were significantly more common in the high vibration exposure group (n=139) than the low-moderate vibration exposure group (n=54). Mean total lifetime vibration dose among exposed subjects was 15.2 (SD 3.2) m(2) h(3) s(-4) (ln scale). HAVS prevalence was 18% and the prevalence ratio of stage 1 and higher disease in the high vibration exposure group versus the low-moderate vibration exposure group was 4.86 (95% CI 1.19 to 19.80). Hand transmitted vibration is a recognisable problem in tropical countries including Malaysia. The current study has identified clinical symptoms and signs suggesting HAVS among construction workers exposed to hand transmitted vibration in a warm environment.

Occupational hand-arm vibration syndrome in Korea.

PubMed

Yoo, Cheolin; Lee, Ji-Ho; Lee, Choong-Ryeol; Kim, Yangho; Lee, Hun; Choi, Younghee; Kim, Young Wook; Chae, Chang Ho; Kim, Hyokyoung; Koh, Sang Baek; Kim, Euna; Lee, Lu Jin; Lee, Kiyoung

2005-06-01

It is suspected that there is a large number of patients suffering from hand-arm vibration syndrome (HAVS) in Korea. However, no cases have been reported since 1992. This study was conducted to identify HAVS cases and determine the characteristics of the syndrome. In April 2001, the Busan, Ulsan, and Gyeong-Nam Province Occupational Disease Surveillance System (BUGODSS) was established to identify work-related HAVS and other occupational diseases. In the 2 years of this project, occupational physicians from five hospitals in these provinces collected information by way of interviews and questionnaires during mandatory occupational medical examinations. Among the initial 189 suspected HAVS cases, 58 volunteers were given cold-water provocation tests in order to diagnose the vascular component of the disorder. One hundred fifty-four approximately occupational HAVS cases were identified from ca. 21,000 workers. One hundred fifty about of these cases were male. The cases were most often found in workers from the shipbuilding industry, and the grinder was the most common source of vibration exposure. Cases of sensorineural disorder (SD) were more common than cases of vascular disorder (VD). The mean values of the finger skin temperature and its recovery rate at 5 min and 10 min after cold-water provocation were significantly lower in the group with the VD than in the group with the SD. We identified 154 occupational HAVS cases, although no cases have been reported during the occupational medical examinations mandated by the state. The majority of the cases were in workers that used grinders in the shipbuilding industry. We determined that peripheral VD and peripheral SD can progress independently of each other. We conclude that exposure to hand-transmitted vibration (HTV) and HAVS cases are common in shipbuilding industry in Korea. The recovery rate of finger skin temperature after cold-water provocation is one of the useful methods for diagnosing the vascular component

Dose-response relation between exposure to two types of hand-arm vibration and sensorineural perception of vibration.

PubMed

Virokannas, H

1995-05-01

31 railway workers and 32 lumberjacks were examined to compare the dose-response relation between the exposure to two types of hand-arm vibration and the sensory disturbances in peripheral nerves as evaluated by the vibration perception thresholds (VPTs). Clinical examinations were carried out that included measurements of the VPTs, and electroneuromyography (ENMG), and an inquiry to confirm the use of vibrating tools. Diseases of the central nervous system and neuropathies were checked by inquiry and a clinical examination, diabetes was excluded by a blood sample analysis, and the subjects with carpal tunnel syndrome confirmed with ENMG were excluded from the study. Lifetime use of hand held tamping machines (railway workers) and chain saws (lumberjacks) had a significant correlation with the VPTs at frequencies from 32 to 500 Hz. The increase of the VPTs (250 Hz) in relation to use of vibrating tools was 1.8-fold higher on average in the whole group and 2.3-fold higher in the young (< 45) railway workers who had used hand held tamping machines, than in the corresponding groups of lumberjacks, who had used chain saws, whereas the frequency weighted acceleration of vibration in tamping machines was fourfold. There was a significant dose-response relation between the exposure to hand-arm vibration and the VPTs. The VPTs as a function of the frequency weighted acceleration of vibration and the exposure to vibration gave promising results for assessment of the risk of damage to sensory nerves induced by vibration.

Assessment of thermotactile and vibrotactile thresholds for detecting sensorineural components of the hand-arm vibration syndrome (HAVS).

PubMed

Ye, Ying; Griffin, Michael J

2018-01-01

Thermotactile thresholds and vibrotactile thresholds are measured to assist the diagnosis of the sensorineural component of the hand-arm vibration syndrome (HAVS). This study investigates whether thermotactile and vibrotactile thresholds distinguish between fingers with and without numbness and tingling. In 60 males reporting symptoms of the hand-arm vibration syndrome, thermotactile thresholds for detecting hot and cold temperatures and vibrotactile thresholds at 31.5 and 125 Hz were measured on the index and little fingers of both hands. In fingers reported to suffer numbness or tingling, hot thresholds increased, cold thresholds decreased, and vibrotactile thresholds at both 31.5 and 125 Hz increased. With sensorineural symptoms on all three phalanges (i.e. numbness or tingling scores of 6), both thermotactile thresholds and both vibrotactile thresholds had sensitivities greater than 80% and specificities around 90%, with areas under the receiver operating characteristic curves around 0.9. There were correlations between all four thresholds, but cold thresholds had greater sensitivity and greater specificity on fingers with numbness or tingling on only the distal phalanx (i.e. numbness or tingling scores of 1) suggesting cold thresholds provide better indications of early sensorineural disorder. Thermotactile thresholds and vibrotactile thresholds can provide useful indications of sensorineural function in patients reporting symptoms of the sensorineural component of HAVS.

Research on simultaneous impact of hand-arm and whole-body vibration.

PubMed

Kowalski, Piotr; Zając, Jacek

2012-01-01

This article presents the results of laboratory tests on the combined effect of whole-body vibration (WBV) and hand-arm vibration (HAV). The reactions of subjects exposed to various combinations of vibration were recorded. The vibrotactile perception threshold (VPT) test identified changes caused by exposure to vibration. Ten male subjects met the criteria of the study. There were 4 series of tests: a reference test and tests after exposure to HAV, WBV, and after simultaneous exposure to HAV and WBV. An analysis of the results (6000 ascending and descending VPTs) showed that the changes in VPTs were greatest after simultaneous exposure to both kinds of vibration. The increase in VPT, for all stimulus frequencies, was then higher than after exposure to HAV or WBV only.

Does intraoperative navigation improve the accuracy of pedicle screw placement in the apical region of dystrophic scoliosis secondary to neurofibromatosis type I: comparison between O-arm navigation and free-hand technique.

PubMed

Jin, Mengran; Liu, Zhen; Liu, Xingyong; Yan, Huang; Han, Xiao; Qiu, Yong; Zhu, Zezhang

2016-06-01

To assess the accuracy of O-arm-navigation-based pedicle screw insertion in dystrophic scoliosis secondary to NF-1 and compare it with free-hand pedicle screw insertion technique. 32 patients with dystrophic NF-1-associated scoliosis were divided into two groups. A total of 92 pedicle screws were implanted in apical region (two vertebrae above and below the apex each) in 13 patients using O-arm-based navigation (O-arm group), and 121 screws were implanted in 19 patients using free-hand technique (free-hand group). The postoperative CT images were reviewed and analyzed for pedicle violation. The screw penetration was divided into four grades: grade 0 (ideal placement), grade 1 (penetration <2 mm), grade 2 (penetration between 2 and 4 mm), and grade 3 (penetration >4 mm). The accuracy rate of pedicle screw placement (grade 0, 1) was significantly higher in the O-arm group (79 %, 73/92) compared to 67 % (81/121) of the free-hand group (P = 0.045). Meanwhile, a significantly lower prevalence of grade 2-3 perforation was observed in the O-arm group (21 vs. 33 %, P < 0.05), and the incidence of medial perforation was significantly minimized by using O-arm navigation compared to free-hand technique (2 vs. 15 %, P < 0.01). Moreover, the implant density in apical region was significantly elevated by using O-arm navigation (58 vs. 42 %, P < 0.001). We reported 79 % accuracy of O-arm-based pedicle screw placement in dystrophic NF-1-associated scoliosis. O-arm navigation system does facilitate pedicle screw insertion in dystrophic NF-1-associated scoliosis, demonstrating superiorities in the safety and accuracy of pedicle screw placement in comparison with free-hand technique.

Cross-Cultural Adaptation of the Disability of Arm, Shoulder, and Hand Questionnaire: Spanish for Puerto Rico Version

ERIC Educational Resources Information Center

Mulero-Portela, Ana L.; Colon-Santaella, Carmen L.; Cruz-Gomez, Cynthia

2009-01-01

The purpose of this study was to perform a cross-cultural adaptation of the Disability of Arm, Shoulder, and Hand (DASH) questionnaire to Spanish for Puerto Rico. Five steps were followed for the cross-cultural adaptation: forward translations into Spanish for Puerto Rico, synthesis of the translations, back translations into English, revision by…

Determination of muscle mass changes in legs from K-40 measurements

NASA Technical Reports Server (NTRS)

Palmer, H. E.; Rieksts, G. A.

1979-01-01

The K-40 content of the upper legs was periodically measured in several subjects whose injured legs had been in a cast for 6 weeks or more. As the subjects began using the leg again, the K-40 content increased as the muscle tissue was replaced. A 25% increase in K-40 content in 6 months is typical for a normal leg use and recovery. This is equivalent to an original muscle mass loss of 20%. By measuring specific body regions, such as arms or legs, with a high-efficiency detector system, muscle mass changes which exceed a few percent can be measured. These methods could be used in space flight and bedrest studies, and in studying nutritional deficiencies due to disease or diet.

Hand-arm vibration syndrome in South African gold miners.

PubMed

Nyantumbu, Busi; Barber, Chris M; Ross, Mary; Curran, Andrew D; Fishwick, David; Dias, Belinda; Kgalamono, Spo; Phillips, James I

2007-01-01

Hand-arm vibration syndrome (HAVS) is associated with the use of hand-held vibrating tools. Affected workers may experience symptoms of tingling, numbness, loss of grip strength and pain. Loss of dexterity may impair everyday activities, and potentially increase the risk of occupational accidents. Although high vibration levels (up to 31 m/s(2)) have been measured in association with rock drills, HAVS has not been scientifically evaluated in the South African mining industry. The aim of this study was to determine the prevalence and severity of HAVS in South African gold miners, and to identify the tools responsible. A cross-sectional study was conducted in a single South African gold-mine. Participants were randomly selected from mineworkers returning from annual leave, comprising 156 subjects with occupational exposure to vibration, and 140 workers with no exposure. Miners who consented to participate underwent a clinical HAVS assessment following the UK Health and Safety Laboratory protocol. The prevalence of HAVS in vibration-exposed gold miners was 15%, with a mean latent period of 5.6 years. Among the non-exposed comparison group, 5% had signs and symptoms indistinguishable from HAVS. This difference was statistically significant (P < 0.05). All the cases of HAVS gave a history of exposure to rock drills. The study has diagnosed the first cases of HAVS in the South African mining industry. The prevalence of HAVS was lower than expected, and possible explanations for this may include a survivor population, and lack of vascular symptom reporting due to warm-ambient temperatures.

Diagnostic criteria and staging of hand-arm vibration syndrome in the United Kingdom.

PubMed

McGeoch, Kenneth L; Lawson, Ian J; Burke, Frank; Proud, George; Miles, Jeremy

2005-07-01

In the United Kingdom the diagnosis of Hand-arm Vibration Syndrome varies depending on the purpose of that diagnosis. The criteria differ in three situations. More than 100,000 miners and ex-miners with claims for HAVS have been examined using a Medical Assessment Process which included the use of standardised tests. This contract is unique but it has had significant effects on the two other processes. The Industrial Injuries Disablement Benefit Scheme provides a benefit that can be paid to an employed earner because of an accident or Prescribed Disease. New recommendations have been published to remove the anomalies in the present format for assessing HAVS. If implemented the new scheme will recognise the Stockholm Workshop Scales and workers with neurological problems will also be compensated. The Health and Safety Executive will issue new guidance in the near future on the hazards of hand-arm vibration. Health surveillance in the workplace will be fundamental and the HSE propose a tiered approach with levels 1 to 5. Specialist occupational nurses and doctors with training in the diagnosis and assessment of HAVS will be needed for levels 3 and 4. Only at this level may a diagnosis of HAVS be made. The Medical Assessment Process has demonstrated that it is possible to examine a large number of claimants in a standardised manner. The IIAC and HSE recommendations contain very important improvements on the existing positions in the UK and it must be hoped that they will be implemented in the near future.

The Relation of Hand and Arm Configuration Variances while Tracking Geometric Figures in Parkinson's Disease: Aspects for Rehabilitation

ERIC Educational Resources Information Center

Keresztenyi, Zoltan; Cesari, Paola; Fazekas, Gabor; Laczko, Jozsef

2009-01-01

Variances of drawing arm movements between patients with Parkinson's disease and healthy controls were compared. The aim was to determine whether differences in joint synergies or individual joint rotations affect the endpoint (hand position) variance. Joint and endpoint coordinates were measured while participants performed drawing tasks.…

Short daily exposure to hand-arm vibrations in Swedish car mechanics.

PubMed

Barregård, Lars

2003-01-01

The aim of the study was to examine the daily exposure times to hand-arm vibrations in Swedish car mechanics, to test a method for estimating the exposure time without observing the workers for whole days, and to use the results for predicting the prevalence of vibration-induced white fingers (VWF) by the ISO 5349-model. Six garages were surveyed. In each garage, 5-10 car mechanics were observed in random order every 30 seconds throughout working days. The daily exposure time for each mechanic was estimated from the fraction of the observations that the mechanic was exposed. A total of 51 mechanics were observed, most of them on two different working days, yielding estimates for 95 days. The median effective exposure time was 10 minutes per day (95% confidence interval 5-15 minutes, arithmetic mean 14 minutes, maximum 80 minutes), and most of the exposure time was attributable to fastening and loosening nuts. The within-worker and between-worker variability was high (total sigma2 0.99, geometric standard deviation of 2.7). Using the observed exposure time and data on vibration levels of the main tools in Swedish car mechanics (average weighted acceleration level of 3.5 m/s2), the model in ISO-standard 5349 would predict that only three percent of the car mechanics will suffer from VWF after 20 years of exposure. In contrast, a recent survey of VWF showed the prevalence to be 25 percent. The precision of the observation method was estimated and was found to be good for the group daily mean. On the individual level the precision was only acceptable if the daily exposure time was > or = 40 minutes. In conclusion, the daily exposure time was short and the vibration level was limited. Nevertheless, hand-arm vibrations cause VWF in a significant number of car mechanics. The method of observing workers intermittently seemed to work well.

An interpretative phenomenological analysis of the psychological ramifications of hand-arm vibration syndrome.

PubMed

Ayers, Beverley; Forshaw, Mark

2010-05-01

With a substantial number of individuals diagnosed with Hand-Arm Vibration Syndrome (HAVS) and the preponderance of research focused on the medical and paramedical issues, the psychological and mental health sequelae of HAVS are largely neglected within the published literature. A series of focus groups and interviews were conducted involving nine people who had been diagnosed with HAVS. Transcripts of these interviews were analysed using Interpretative Phenomenological Analysis. Four key themes were identified within the discourse of individuals affected by HAVS: machismo; coping; psychological impacts; and the development of support services for HAVS. Clinical implications are briefly discussed.

[Arm Motor Function Recovery during Rehabilitation with the Use of Hand Exoskeleton Controlled by Brain-Computer Interface: a Patient with Severe Brain Damage].

PubMed

Biryukova, E V; Pavlova, O G; Kurganskaya, M E; Bobrov, P D; Turbina, L G; Frolov, A A; Davydov, V I; Sil'tchenko, A V; Mokienko, O A

2016-01-01

We studied the dynamics of motor function recovery in a patient with severe brain damage in the course of neurorehabilitation using hand exoskeleton controlled by brain-computer interface. For estimating the motor function of paretic arm, we used the biomechanical analysis of movements registered during the course of rehabilitation. After 15 weekly sessions of hand exoskeleton control, the following results were obtained: a) the velocity profile of goal-directed movements of paretic hand became bell-shaped, b) the patient began to extend and abduct the hand which was flexed and adducted in the beginning of rehabilitation, and c) the patient began to supinate the forearm which was pronated in the beginning of rehabilitation. The first result is an evidence of the general improvement of the quality of motor control, while the second and third results prove that the spasticity of paretic arm has decreased.

[Design and application of medical electric leg-raising machine].

PubMed

Liang, Jintang; Chen, Jinyuan; Zhao, Zixian; Lin, Jinfeng; Li, Juanhong; Zhong, Jingliang

2017-08-01

Passive leg raising is widely used in clinic, but it lacks of specialized mechanical raise equipment. It requires medical staff to raise leg by hand or requires a multi-functional bed to raise leg, which takes time and effort. Therefore we have developed a new medical electric leg-raising machine. The equipment has the following characteristics: simple structure, stable performance, easy operation, fast and effective, safe and comfortable. The height range of the lifter is 50-120 cm, the range of the angle of raising leg is 10degree angle-80degree angle, the maximum supporting weight is 40 kg. Because of raising the height of the lower limbs and making precise angle, this equipment can completely replace the traditional manner of lifting leg by hand with multi-functional bed to lift patients' leg and can reduce the physical exhaustion and time consumption of medical staff. It can change the settings at any time to meet the needs of the patient; can be applied to the testing of PLR and dynamically assessing the hemodynamics; can prevent deep vein thrombosis and some related complications of staying in bed; and the machine is easy to be cleaned and disinfected, which can effectively avoid hospital acquired infection and cross infection; and can also be applied to emergency rescue of various disasters and emergencies.

Effect of Transcranial Direct Current Stimulation on Severely Affected Arm-Hand Motor Function in Patients After an Acute Ischemic Stroke: A Pilot Randomized Control Trial.

PubMed

Rabadi, Meheroz H; Aston, Christopher E

2017-10-01

The aim of this article was to determine whether cathodal transcranial direct current stimulation (c-tDCS) to unaffected primary motor cortex (PMC) plus conventional occupational therapy (OT) improves functional motor recovery of the affected arm hand in patients after an acute ischemic stroke compared with sham transcranial direct current stimulation plus conventional OT. In this prospective, randomized, double-blinded, sham-controlled trial of 16 severe, acute ischemic stroke patients with severe arm-hand weakness were randomly assigned to either experimental (c-tDCS plus OT; n = 8) or control (sham transcranial direct current stimulation plus OT; n = 8) groups. All patients received a standard 3-hr in-patient rehabilitation therapy, plus an additional ten 30-min sessions of tDCS. During each session, 1 mA of cathodal stimulation to the unaffected PMC is performed followed by the patient's scheduled OT. The primary outcome measure was change in Action Research Arm Test (ARAT) total and subscores on discharge. Application of c-tDCS to unaffected PMC resulted in a clinically relevant 10-point improvement in the affected arm-hand function based on ARAT total score compared with a 2-point improvement in the control group. Application of 30-min of c-tDCS to the unaffected PMC showed a 10-point improvement in the ARAT score. This corresponds to a large effect size in improvement of affected arm-hand function in patients with severe, acute ischemic stroke. Although not statistically significant, this suggests that larger studies, enrolling at least 25 patients in each group, and with a longer follow-up are warranted.

Dose-response relation between exposure to two types of hand-arm vibration and sensorineural perception of vibration.

PubMed Central

Virokannas, H

1995-01-01

OBJECTIVES--31 railway workers and 32 lumberjacks were examined to compare the dose-response relation between the exposure to two types of hand-arm vibration and the sensory disturbances in peripheral nerves as evaluated by the vibration perception thresholds (VPTs). METHODS--Clinical examinations were carried out that included measurements of the VPTs, and electroneuromyography (ENMG), and an inquiry to confirm the use of vibrating tools. Diseases of the central nervous system and neuropathies were checked by inquiry and a clinical examination, diabetes was excluded by a blood sample analysis, and the subjects with carpal tunnel syndrome confirmed with ENMG were excluded from the study. RESULTS--Lifetime use of hand held tamping machines (railway workers) and chain saws (lumberjacks) had a significant correlation with the VPTs at frequencies from 32 to 500 Hz. The increase of the VPTs (250 Hz) in relation to use of vibrating tools was 1.8-fold higher on average in the whole group and 2.3-fold higher in the young (< 45) railway workers who had used hand held tamping machines, than in the corresponding groups of lumberjacks, who had used chain saws, whereas the frequency weighted acceleration of vibration in tamping machines was fourfold. CONCLUSION--There was a significant dose-response relation between the exposure to hand-arm vibration and the VPTs. The VPTs as a function of the frequency weighted acceleration of vibration and the exposure to vibration gave promising results for assessment of the risk of damage to sensory nerves induced by vibration. PMID:7795756

Synergy effects of combined multichannel EMG-triggered electrical stimulation and mirror therapy in subacute stroke patients with severe or very severe arm/hand paresis.

PubMed

Schick, Thomas; Schlake, Hans-Peter; Kallusky, Juliane; Hohlfeld, Günter; Steinmetz, Maria; Tripp, Florian; Krakow, Karsten; Pinter, Michaela; Dohle, Christian

2017-01-01

Neurorehabilitation requires the development of severity-dependent and successful therapies for arm/hand rehabilitation in stroke patients. To evaluate the effectiveness of adding mirror therapy to bilateral EMG-triggered multi-channel electrostimulation for the treatment of severe arm/hand paresis in stroke patients. The subjects of this randomized, controlled, multicentre study were stroke patients who had suffered their first insult between 1 and 6 months before study start and had severe or very severe arm/hand paresis, as classified by Fugl-Meyer-Assessment. Subjects were randomly allocated to an intervention group (n = 16) or control group (n = 17). Both groups were treated for 3 weeks (5x week, 30 minutes) with bilateral EMG-triggered multi-channel electrostimulation. The intervention group additionally received mirror feedback of the unaffected limb. The primary outcome measure was motor recovery of the upper extremities, as measured by the Fugl-Meyer Assessment. The Intervention Group with very severe paresis had significantly better motor recovery in total Fugl-Meyer Assessment (p = 0.017) at a medium effect size (Cohen) of d = 0.7, due to a significant recovery of shoulder and elbow function (p = 0.003) in the Fugl-Meyer Assessment Part A subtest. For subjects with severe paresis, additional mirror therapy did not significantly influence outcome. Additional mirror therapy in combination with EMG-triggered multi-channel electrostimulation is therapeutically beneficial for post-acute stroke patients with very severe arm/hand paresis.

Evaluation of feedforward and feedback contributions to hand stiffness and variability in multijoint arm control.

PubMed

He, Xin; Du, Yu-Fan; Lan, Ning

2013-07-01

The purpose of this study is to validate a neuromechanical model of the virtual arm (VA) by comparing emerging behaviors of the model to those of experimental observations. Hand stiffness of the VA model was obtained by either theoretical computation or simulated perturbations. Variability in hand position of the VA was generated by adding signal dependent noise (SDN) to the motoneuron pools of muscles. Reflex circuits of Ia, Ib and Renshaw cells were included to regulate the motoneuron pool outputs. Evaluation of hand stiffness and variability was conducted in simulations with and without afferent feedback under different patterns of muscle activations during postural maintenance. The simulated hand stiffness and variability ellipses captured the experimentally observed features in shape, magnitude and orientation. Steady state afferent feedback contributed significantly to the increase in hand stiffness by 35.75±16.99% in area, 18.37±7.80% and 16.15±7.15% in major and minor axes; and to the reduction of hand variability by 49.41±21.19% in area, 36.89±12.78% and 18.87±23.32% in major and minor axes. The VA model reproduced the neuromechanical behaviors that were consistent with experimental data, and it could be a useful tool for study of neural control of posture and movement, as well as for application to rehabilitation.

A systematic review of the etiopathogenesis of Kienböck's disease and a critical appraisal of its recognition as an occupational disease related to hand-arm vibration

PubMed Central

2012-01-01

Background We systematically reviewed etiological factors of Kienböck’s disease (osteonecrosis of the lunate) discussed in the literature in order to examine the justification for including Kienböck’s disease (KD) in the European Listing of Occupational Diseases. Methods We searched the Ovid/Medline and the Cochrane Library for articles discussing the etiology of osteonecrosis of the lunate published since the first description of KD in 1910 and up until July 2012 in English, French or German. Literature was classified by the level of evidence presented, the etiopathological hypothesis discussed, and the author's conclusion about the role of the etiopathological hypothesis. The causal relationship between KD and hand-arm vibration was elucidated by the Bradford Hill criteria. Results A total of 220 references was found. Of the included 152 articles, 140 (92%) reached the evidence level IV (case series). The four most frequently discussed factors were negative ulnar variance (n=72; 47%), primary arterial ischemia of the lunate (n=63; 41%), trauma (n=63; 41%) and hand-arm vibration (n=53; 35%). The quality of the cohort studies on hand-arm vibration did not permit a meta-analysis to evaluate the strength of an association to KD. Evidence for the lack of consistency, plausibility and coherence of the 4 most frequently discussed etiopathologies was found. No evidence was found to support any of the nine Bradford Hill criteria for a causal relationship between KD and hand-arm vibration. Conclusions A systematic review of 220 articles on the etiopathology of KD and the application of the Bradford Hill criteria does not provide sufficient scientific evidence to confirm or refute a causal relationship between KD and hand-arm vibration. This currently suggests that, KD does not comply with the criteria of the International Labour Organization determining occupational diseases. However, research with a higher level of evidence is required to further determine if hand-arm

A systematic review of the etiopathogenesis of Kienböck's disease and a critical appraisal of its recognition as an occupational disease related to hand-arm vibration.

PubMed

Stahl, Stéphane; Stahl, Adelana Santos; Meisner, Christoph; Rahmanian-Schwarz, Afshin; Schaller, Hans-Eberhard; Lotter, Oliver

2012-11-21

We systematically reviewed etiological factors of Kienböck's disease (osteonecrosis of the lunate) discussed in the literature in order to examine the justification for including Kienböck's disease (KD) in the European Listing of Occupational Diseases. We searched the Ovid/Medline and the Cochrane Library for articles discussing the etiology of osteonecrosis of the lunate published since the first description of KD in 1910 and up until July 2012 in English, French or German. Literature was classified by the level of evidence presented, the etiopathological hypothesis discussed, and the author's conclusion about the role of the etiopathological hypothesis. The causal relationship between KD and hand-arm vibration was elucidated by the Bradford Hill criteria. A total of 220 references was found. Of the included 152 articles, 140 (92%) reached the evidence level IV (case series). The four most frequently discussed factors were negative ulnar variance (n=72; 47%), primary arterial ischemia of the lunate (n=63; 41%), trauma (n=63; 41%) and hand-arm vibration (n=53; 35%). The quality of the cohort studies on hand-arm vibration did not permit a meta-analysis to evaluate the strength of an association to KD. Evidence for the lack of consistency, plausibility and coherence of the 4 most frequently discussed etiopathologies was found. No evidence was found to support any of the nine Bradford Hill criteria for a causal relationship between KD and hand-arm vibration. A systematic review of 220 articles on the etiopathology of KD and the application of the Bradford Hill criteria does not provide sufficient scientific evidence to confirm or refute a causal relationship between KD and hand-arm vibration. This currently suggests that, KD does not comply with the criteria of the International Labour Organization determining occupational diseases. However, research with a higher level of evidence is required to further determine if hand-arm vibration is a risk factor for KD.

pGALS – paediatric Gait Arms Legs and Spine: a simple examination of the musculoskeletal system

PubMed Central

2013-01-01

We describe pGALS (paediatric Gait, Arms, Legs and Spine) – a simple quick musculoskeletal assessment to distinguish abnormal from normal joints in children and young people. The use of pGALS is aimed at the non-specialist in paediatric musculoskeletal medicine as a basic clinical skill to be used in conjunction with essential knowledge about red flags, normal development and awareness of patterns of musculoskeletal pathologies. pGALS has been validated in school-aged children and also in the context of acute general paediatrics to detect abnormal joints. We propose that pGALS is an important part of basic clinical skills to be acquired by all doctors who may be involved in the care of children. The learning of pGALS along with basic knowledge is a useful way to increase awareness of joint disease, facilitate early recognition of joint problems and prompt referral to specialist teams to optimise clinical outcomes. We have compiled this article as a resource that can be used by the paediatric rheumatology community to facilitate teaching. PMID:24219838

Intelligent control of robotic arm/hand systems for the NASA EVA retriever using neural networks

NASA Technical Reports Server (NTRS)

Mclauchlan, Robert A.

1989-01-01

Adaptive/general learning algorithms using varying neural network models are considered for the intelligent control of robotic arm plus dextrous hand/manipulator systems. Results are summarized and discussed for the use of the Barto/Sutton/Anderson neuronlike, unsupervised learning controller as applied to the stabilization of an inverted pendulum on a cart system. Recommendations are made for the application of the controller and a kinematic analysis for trajectory planning to simple object retrieval (chase/approach and capture/grasp) scenarios in two dimensions.

Delivery of health surveillance for hand-arm vibration in the West Midlands.

PubMed

Kinoulty, Mary

2006-01-01

Concerns about provider competence and quality of hand-arm vibrations (HAVs) health surveillance programmes were identified by Health & Safety Executive (HSE) inspectors. To evaluate health surveillance programmes and compare them with published HSE guidance. To identify deficiencies and areas for improvement in the health surveillance programmes. A proforma was developed for the study and used on a sample of 10 local occupational health providers. All 10 organizations were aware of current HSE guidance for health surveillance for HAVs but only a minority (30%) were following it. Occupational health provider training, written procedures and health surveillance delivery were all identified as areas requiring improvement. The majority of organizations were not following HSE guidance. Occupational health providers undertaking health surveillance for HAV require specific training.

Associations of work activities requiring pinch or hand grip or exposure to hand-arm vibration with finger and wrist osteoarthritis: a meta-analysis.

PubMed

Hammer, Paula E C; Shiri, Rahman; Kryger, Ann I; Kirkeskov, Lilli; Bonde, Jens Peter

2014-03-01

We systematically reviewed the epidemiologic evidence linking finger and wrist osteoarthritis (OA) with work activities requiring pinch or hand grip or exposure to hand-arm vibration (HAV). PubMed and Embase databases were searched up to June 2013. We selected studies assessing the associations of radiographic diagnosed finger and/or wrist joint OA with work activities involving pinch or hand grip or exposure to HAV. We used specific criteria to evaluate completeness of reporting, potential confounding, and bias. Pooled odds ratios (OR) were computed using random-effects meta-analyses. Of the 19 studies included, 17 were cross-sectional, 1 was a prospective cohort, and 1 a case-control study. The meta-analyses of studies that controlled their estimates for at least age and gender showed the associations of pinch grip work with proximal interphalangeal joint [OR 1.56, 95% confidence interval (95% CI) 1.09-2.23] and the first carpometacarpal joint OA (OR 2.10, 95% CI 1.06-4.17), but not with distal interphalangeal, metacarpalphalangeal, or wrist joints OA. Hand grip work and exposure to HAV were not associated with any finger or wrist OA. Epidemiological studies provide limited evidence that pinch grip may increase the risk of wrist or finger OA, but causal relation cannot be resolved because of cross-sectional designs and inadequate characterization of biomechanical strain to the hand and wrist.

The Effect of Restricted Arm Swing on Energy Expenditure in Healthy Men

ERIC Educational Resources Information Center

Yizhar, Ziva; Boulos, Spiro; Inbar, Omri; Carmeli, Eli

2009-01-01

Arm swing in human walking is an active natural motion involving the upper extremities. Earlier studies have described the interrelationship between arms and legs during walking, but the effect of arm swing on energy expenditure and dynamic parameters during normal gait, is inconclusive. The aim of this study was to investigate the effect of…

Flexible kinesthetic distance perception: when do your arms tell you how far you have walked?

PubMed

Harrison, Steven J; Kuznetsov, Nikita; Breheim, Samuel

2013-01-01

Given the flexible organization of locomotion evidenced in the many ways the limbs can be coordinated, the authors explored the potentially correspondingly flexible organization of nonvisual (kinesthetic) distance perception. As kinesthetic distance perception is known to be affected by how the limbs are coordinated, the authors probed the potential perceptual contribution of the arms during locomotion by manipulating arm-leg coordination patterns in blind-walked distance-matching tasks. Whereas manipulation of arm-leg coordination for walking with free-swinging arms had no observable perceptual consequences, comparable manipulation for walking with hiking poles did affect distance matching. These results suggest that under conditions in which the arms act to propel the body (e.g., crawling or stair-climbing) a person's nonvisual sense of movement is conveyed in the coordinated actions of all four limbs.

Syringomyelia

MedlinePlus

... are symptoms, they may include: Headache Loss of muscle mass ( wasting , atrophy), often in the arms and hands Spasms or tightness in the leg or hand and arm muscles Muscle function loss , loss of ability to use ...

Hand-arm vibration syndrome from exposure to high-pressure hoses.

PubMed

Cooke, R; House, R; Lawson, I J; Pelmear, P L; Wills, M

2001-09-01

Hand-arm vibration syndrome has been reported in the literature to occur following exposure to vibration from the use of many tools, but to date there have been no case reports of its occurrence in workers who have used high-pressure hoses, alone or with other tools. To remedy this, the case histories of nine subjects (two without mixed exposure) examined in the UK and Canada are presented, together with their severity classified according to the Stockholm scales. Attention is drawn to the need to use multiple diagnostic tests to establish the diagnosis and the need to implement vibration isolation and damping methodologies, as and when feasible, with respect to hose nozzles in order to minimize the hazard. The ultimate goal for tool manufacturers, hygienists and engineers should be to reduce workplace vibration levels to meet national and international guidelines and legislation, including UK Health & Safety Executive guidelines and European Economic Community directives. The respective risk levels are presented, together with vibration measurements on hoses used by some of the cases.

THE EFFECT OF HAND DOMINANCE ON MARTIAL ARTS STRIKES

PubMed Central

Neto, Osmar Pinto; Silva, Jansen Henrique; de Miranda Marzullo, Ana Carolina; Bolander, Richard P.; Bir, Cynthia A.

2011-01-01

The main goal of this study was to compare dominant and non-dominant martial arts palm strikes under different circumstances that usually happen during martial arts and combative sports applications. Seven highly experienced (10 ± 5 years) right hand dominant Kung Fu practitioners performed strikes with both hands, stances with left or right lead legs, and with the possibility or not of stepping towards the target (moving stance). Peak force was greater for the dominant hand strikes (1593.76 ± 703.45 N vs. 1042.28 ± 374.16 N; p < .001), whereas no difference was found in accuracy between the hands (p = .141). Additionally, peak force was greater for the strikes with moving stance (1448.75 ± 686.01 N vs. 1201.80 ± 547.98 N; p = .002) and left lead leg stance (1378.06 ± 705.48 N vs.1269.96 ± 547.08 N). Furthermore, the difference in peak force between strikes with moving and stationary stances was statistically significant only for the strikes performed with a left lead leg stance (p = .007). Hand speed was higher for the dominant hand strikes (5.82 ± 1.08 m/s vs. 5.24 ± 0.78 m/s; p = 0.001) and for the strikes with moving stance (5.79 ± 1.01 m/s vs. 5.29 ± 0.90 m/s; p < .001). The difference in hand speed between right and left hand strikes was only significant for strikes with moving stance. In summary, our results suggest that the stronger palm strike for a right-handed practitioner is a right hand strike on a left lead leg stance moving towards the target. PMID:22047701

Are the hamstrings from the drive leg or landing leg more active in baseball pitchers? An electromyographic study.

PubMed

Erickson, Brandon J; Zaferiou, Antonia; Chalmers, Peter N; Ruby, Deana; Malloy, Phillip; Luchetti, Timothy J; Verma, Nikhil N; Romeo, Anthony A

2017-11-01

Ulnar collateral ligament reconstruction (UCLR) has become a common procedure among baseball players of all levels. There are several graft choices in performing UCLR, one of which is a hamstring (gracilis or semitendinosus) autograft. It is unclear whether the hamstring muscle from a pitcher's drive leg (ipsilateral side of the UCLR) or landing leg (contralateral side of the UCLR) is more active during the pitching motion. We hypothesized that the landing leg semitendinosus will be more electromyographically active than the drive leg. Healthy, elite male pitchers aged 16-21 years were recruited. Sixteen pitchers (average age, 17.6 ± 1.6 years; 67% threw right handed) underwent electromyographic analysis. Pitchers threw 5 fastballs at 100% effort from the wind-up with electromyographic analysis of every pitch. Activation of the semitendinosus and biceps femoris in both legs was compared within pitchers and between pitchers. Hamstring activity was higher in the drive leg than in the landing leg during each phase and in sum, although the difference was significant only during the double support phase (P = .021). On within-pitcher analysis, 10 of 16 pitchers had significantly more sum hamstring activity in the drive leg than in the landing leg, while only 4 of 16 had more activity in the landing leg (P = .043). During the baseball pitch, muscle activity of the semitendinosus was higher in the drive leg than in the landing leg in most pitchers. Surgeons performing UCLR using hamstring autograft should consider harvesting the graft from the pitcher's landing leg to minimize disruption to the athlete's pitching motion. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

A Comparison of Image Quality and Radiation Exposure Between the Mini C-Arm and the Standard C-Arm.

PubMed

van Rappard, Juliaan R M; Hummel, Willy A; de Jong, Tijmen; Mouës, Chantal M

2018-04-01

The use of intraoperative fluoroscopy has become mandatory in osseous hand surgery. Due to its overall practicality, the mini C-arm has gained popularity among hand surgeons over the standard C-arm. This study compares image quality and radiation exposure for patient and staff between the mini C-arm and the standard C-arm, both with flat panel technology. An observer-based subjective image quality study was performed using a contrast detail (CD) phantom. Five independent observers were asked to determine the smallest circles discernable to them. The results were plotted in a graph, forming a CD curve. From each curve, an image quality figure (IQF) was derived. A lower IQF equates to a better image quality. The patients' entrance skin dose was measured, and to obtain more information about the staff exposure dose, a perspex hand phantom was used. The scatter radiation was measured at various distances and angles relative to a central point on the detector. The IQF was significantly lower for the mini C-arm resulting in a better image quality. The patients' entrance dose was 10 times higher for the mini C-arm as compared with the standard C-arm, and the scatter radiation threefold. Due to its improved image quality and overall practicality, the mini C-arm is recommended for hand surgical procedures. To ensure that the surgeons' radiation exposure is not exceeding the safety limits, monitoring radiation exposure using mini C-arms with flat panel technology during surgery should be done in a future clinical study.

Summary of compliant and multi-arm control at NASA. Langley Research Center

NASA Technical Reports Server (NTRS)

Harrison, Fenton W.

1992-01-01

The topics are presented in viewgraph form and include the: single arm system, single arm axis system, single arm control systems, single arm hand controller axis system, single arm position axis system, single arm vision axis system, single arm force axis system, multi-arm system, multi-arm axis system, and the dual arm hand control axis system with control signals.

Case Study: Physical Capacity and Nutritional Status Before and After a Single-Handed Yacht Race.

PubMed

Ghiani, Giovanna; Magnani, Sara; Doneddu, Azzurra; Sainas, Gianmarco; Pinna, Virginia; Caboi, Marco; Palazzolo, Girolamo; Tocco, Filippo; Crisafulli, Antonio

2018-06-12

During solitary sailing, the sailor is exposed to sleep deprivation and difficulties in consuming regular meals. Sailor weight loss is often reported. In the present case study, we describe changes in the physical capacity and nutritional status of an athlete attempting a single-handed yacht race around the globe. An Italian male ocean racer (Gaetano Mura) asked for our help to reach an optimum level of physical and nutritional preparation. We planned his diet after assessing his anthropometric parameters and body composition, as well as his usual energy intake and nutritional expenditure. The diet consisted of 120 meals stored in sealed plastic bags. Before his departure, GM performed two incremental exercise tests (cycle ergometry and arm crank ergometry) to assess his physical capacity. Cardiac functions were also estimated by Doppler echocardiography. All measures and exercise tests were repeated 10 days after GM finished the race, which lasted 64 days. Anthropometric measures did not change significantly, with the exception of arm fat area and thigh muscle area, which decreased. There were evident increments in maximum oxygen intake and maximum workload during arm cranking after the race. On the contrary, maximum oxygen uptake and maximum workload decreased during cycling. Finally, end-diastolic and stroke volume decreased after the race. It was concluded that nutritional counseling was useful to avoid excessive changes in nutritional status and body composition due to 64 days of solitary navigation. However, a reduction in physical leg capacity and cardiovascular functions secondary to leg disuse were present.

[Clinical efficacy of mouse nerve growth factor in treatment of occupational hand-arm vibration disease].

PubMed

Fan, Chunyue; Wang, Yanyan; Zhang, Ying; Lang, Li; Deng, Xiaofeng; Cheng, Ying

2014-12-01

To investigate the efficacy of mouse nerve growth factor (mNGF) in treating occupational hand-arm vibration disease (HAVD). Sixty-four patients with HAVD were equally and randomly divided into treatment group and control group. The control group was given Salvia miltiorrhiza Bunge and deproteinized extract of calf blood to improve circulation, and also given methylcobalamin tablets and vitamin B6 for neurotrophic treatment. In addition to the above treatments for the control group, the treatment group was also given 30 µg/d mNGF by intramuscular injection for two courses (4 weeks for each course) with a 15-day interval. Both the treatment group and the control group showed significant improvements in clinical symptoms and signs (hand numbness and pain, and reduced senses of touch, pain, and vibration), cold water loading test (CWLT), and electroneuromyography (ENMG) after treatments (P < 0.05). And the treatment group had significantly more improvements than the control group (P < 0.05). mNGF can significantly improve hand numbness and pain, reduced senses of touch, pain, and vibration, CWLT, and ENMG, so it has better clinical effect and safety in treating HAVD. Early diagnosis and treatment can improve the outcome of patients with HAVD.

Decoding static and dynamic arm and hand gestures from the JPL BioSleeve

NASA Astrophysics Data System (ADS)

Wolf, M. T.; Assad, C.; Stoica, A.; You, Kisung; Jethani, H.; Vernacchia, M. T.; Fromm, J.; Iwashita, Y.

This paper presents methods for inferring arm and hand gestures from forearm surface electromyography (EMG) sensors and an inertial measurement unit (IMU). These sensors, together with their electronics, are packaged in an easily donned device, termed the BioSleeve, worn on the forearm. The gestures decoded from BioSleeve signals can provide natural user interface commands to computers and robots, without encumbering the users hands and without problems that hinder camera-based systems. Potential aerospace applications for this technology include gesture-based crew-autonomy interfaces, high degree of freedom robot teleoperation, and astronauts' control of power-assisted gloves during extra-vehicular activity (EVA). We have developed techniques to interpret both static (stationary) and dynamic (time-varying) gestures from the BioSleeve signals, enabling a diverse and adaptable command library. For static gestures, we achieved over 96% accuracy on 17 gestures and nearly 100% accuracy on 11 gestures, based solely on EMG signals. Nine dynamic gestures were decoded with an accuracy of 99%. This combination of wearableEMGand IMU hardware and accurate algorithms for decoding both static and dynamic gestures thus shows promise for natural user interface applications.

Replantation (Finger, Hand, or Arm)

MedlinePlus

... is Replantation? Find a hand surgeon near you. Videos Figures Figure 1: Replantation refers to the surgical ... or "in." Also, avoid using media types like "video," "article," and "picture." Tip 4: Your results can ...

The effect of hand dominance on martial arts strikes.

PubMed

Neto, Osmar Pinto; Silva, Jansen Henrique; Marzullo, Ana Carolina de Miranda; Bolander, Richard P; Bir, Cynthia A

2012-08-01

The main goal of this study was to compare dominant and non-dominant martial arts palm strikes under different circumstances that usually happen during martial arts and combative sports applications. Seven highly experienced (10±5 years) right hand dominant Kung Fu practitioners performed strikes with both hands, stances with left or right lead legs, and with the possibility or not of stepping towards the target (moving stance). Peak force was greater for the dominant hand strikes (1593.76±703.45 N vs. 1042.28±374.16 N; p<.001), whereas no difference was found in accuracy between the hands (p=.141). Additionally, peak force was greater for the strikes with moving stance (1448.75±686.01 N vs. 1201.80±547.98 N; p=.002) and left lead leg stance (1378.06±705.48 N vs. 1269.96±547.08 N). Furthermore, the difference in peak force between strikes with moving and stationary stances was statistically significant only for the strikes performed with a left lead leg stance (p=.007). Hand speed was higher for the dominant hand strikes (5.82±1.08 m/s vs. 5.24±0.78 m/s; p=.001) and for the strikes with moving stance (5.79±1.01 m/s vs. 5.29±0.90 m/s; p<.001). The difference in hand speed between right and left hand strikes was only significant for strikes with moving stance. In summary, our results suggest that the stronger palm strike for a right-handed practitioner is a right hand strike on a left lead leg stance moving towards the target. Copyright © 2011 Elsevier B.V. All rights reserved.

Walking the talk--speech activates the leg motor cortex.

PubMed

Liuzzi, Gianpiero; Ellger, Tanja; Flöel, Agnes; Breitenstein, Caterina; Jansen, Andreas; Knecht, Stefan

2008-09-01

Speech may have evolved from earlier modes of communication based on gestures. Consistent with such a motor theory of speech, cortical orofacial and hand motor areas are activated by both speech production and speech perception. However, the extent of speech-related activation of the motor cortex remains unclear. Therefore, we examined if reading and listening to continuous prose also activates non-brachiofacial motor representations like the leg motor cortex. We found corticospinal excitability of bilateral leg muscle representations to be enhanced by speech production and silent reading. Control experiments showed that speech production yielded stronger facilitation of the leg motor system than non-verbal tongue-mouth mobilization and silent reading more than a visuo-attentional task thus indicating speech-specificity of the effect. In the frame of the motor theory of speech this finding suggests that the system of gestural communication, from which speech may have evolved, is not confined to the hand but includes gestural movements of other body parts as well.

Smart Hand For Manipulators

NASA Astrophysics Data System (ADS)

Fiorini, Paolo

1987-10-01

Sensor based, computer controlled end effectors for mechanical arms are receiving more and more attention in the robotics industry, because commonly available grippers are only adequate for simple pick and place tasks. This paper describes the current status of the research at JPL on a smart hand for a Puma 560 robot arm. The hand is a self contained, autonomous system, capable of executing high level commands from a supervisory computer. The mechanism consists of parallel fingers, powered by a DC motor, and controlled by a microprocessor embedded in the hand housing. Special sensors are integrated in the hand for measuring the grasp force of the fingers, and for measuring forces and torques applied between the arm and the surrounding environment. Fingers can be exercised under position, velocity and force control modes. The single-chip microcomputer in the hand executes the tasks of communication, data acquisition and sensor based motor control, with a sample cycle of 2 ms and a transmission rate of 9600 baud. The smart hand described in this paper represents a new development in the area of end effector design because of its multi-functionality and autonomy. It will also be a versatile test bed for experimenting with advanced control schemes for dexterous manipulation.

Evaluation of protective gloves and working techniques for reducing hand-arm vibration exposure in the workplace.

PubMed

Milosevic, Matija; McConville, Kristiina M Valter

2012-01-01

Operation of handheld power tools results in exposure to hand-arm vibrations, which over time lead to numerous health complications. The objective of this study was to evaluate protective equipment and working techniques for the reduction of vibration exposure. Vibration transmissions were recorded during different work techniques: with one- and two-handed grip, while wearing protective gloves (standard, air and anti-vibration gloves) and while holding a foam-covered tool handle. The effect was examined by analyzing the reduction of transmitted vibrations at the wrist. The vibration transmission was recorded with a portable device using a triaxial accelerometer. The results suggest large and significant reductions of vibration with appropriate safety equipment. Reductions of 85.6% were achieved when anti-vibration gloves were used. Our results indicated that transmitted vibrations were affected by several factors and could be measured and significantly reduced.

Electromechanical and robot-assisted arm training for improving activities of daily living, arm function, and arm muscle strength after stroke.

PubMed

Mehrholz, Jan; Pohl, Marcus; Platz, Thomas; Kugler, Joachim; Elsner, Bernhard

2015-11-07

evidence was low to very low. Electromechanical and robot-assisted arm training did not increase the risk of participant drop-out (RD 0.00, 95% CI -0.02 to 0.03, P = 0.84, I² = 0%) with moderate-quality evidence, and adverse events were rare. People who receive electromechanical and robot-assisted arm and hand training after stroke might improve their activities of daily living, arm and hand function, and arm and hand muscle strength. However, the results must be interpreted with caution because the quality of the evidence was low to very low, and there were variations between the trials in the intensity, duration, and amount of training; type of treatment; and participant characteristics.

Hand-arm vibration syndrome: clinical characteristics, conventional electrophysiology and quantitative sensory testing.

PubMed

Rolke, Roman; Rolke, Silke; Vogt, Thomas; Birklein, Frank; Geber, Christian; Treede, Rolf-Detlef; Letzel, Stephan; Voelter-Mahlknecht, Susanne

2013-08-01

Workers exposed to vibrating tools may develop hand-arm vibration syndrome (HAVS). We assessed the somatosensory phenotype using quantitative sensory testing (QST) in comparison to electrophysiology to characterize (1) the most sensitive QST parameter for detecting sensory loss, (2) the correlation of QST and electrophysiology, and (3) the frequency of a carpal tunnel syndrome (CTS) in HAVS. QST, cold provocation tests, fine motor skills, and median nerve neurography were used. QST included thermal and mechanical detection and pain thresholds. Thirty-two patients were examined (54 ± 11 years, 91% men) at the more affected hand compared to 16 matched controls. Vibration detection threshold was the most sensitive parameter to detect sensory loss that was more pronounced in the sensitivity range of Pacinian (150 Hz, x12) than Meissner's corpuscles (20 Hz, x3). QST (84% abnormal) was more sensitive to detect neural dysfunction than conventional electrophysiology (37% abnormal). Motor (34%) and sensory neurography (25%) were abnormal in HAVS. CTS frequency was not increased (9.4%). Findings are consistent with a mechanically-induced, distally pronounced motor and sensory neuropathy independent of CTS. HAVS involves a neuropathy predominantly affecting large fibers with a sensory damage related to resonance frequencies of vibrating tools. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Modeling of biodynamic responses distributed at the fingers and the palm of the human hand-arm system.

PubMed

Dong, Ren G; Dong, Jennie H; Wu, John Z; Rakheja, Subhash

2007-01-01

The objective of this study is to develop analytical models for simulating driving-point biodynamic responses distributed at the fingers and palm of the hand under vibration along the forearm direction (z(h)-axis). Two different clamp-like model structures are formulated to analyze the distributed responses at the fingers-handle and palm-handle interfaces, as opposed to the single driving point invariably considered in the reported models. The parameters of the proposed four- and five degrees-of-freedom models are identified through minimization of an rms error function of the model and measured responses under different hand actions, namely, fingers pull, push only, grip only, and combined push and grip. The results show that the responses predicted from both models agree reasonably well with the measured data in terms of distributed as well total impedance magnitude and phase. The variations in the identified model parameters under different hand actions are further discussed in view of the biological system behavior. The proposed models are considered to serve as useful tools for design and assessment of vibration isolation methods, and for developing a hand-arm simulator for vibration analysis of power tools.

Impedance hand controllers for increasing efficiency in teleoperations

NASA Technical Reports Server (NTRS)

Carignan, C.; Tarrant, J.

1989-01-01

An impedance hand controller with direct force feedback is examined as an alternative to bilateral force reflection in teleoperations involving force contact. Experimentation revealed an operator preference for direct force feedback which provided a better feel of contact with the environment. The advantages of variable arm impedance were also made clear in tracking tests where subjects preferred the larger hand controller inertias made possible by the acceleration feedback loop in the master arm. The ability to decouple the hand controller impedance from the slave arm dynamics is expected to be even more significant when the inertial properties of various payloads in the slave arm are considered.

Roll type conducting polymer legs for rigid-flexible thermoelectric generator

NASA Astrophysics Data System (ADS)

Park, Teahoon; Lim, Hanwhuy; Hwang, Jong Un; Na, Jongbeom; Lee, Hyunki; Kim, Eunkyoung

2017-07-01

A roll-type conducting polymer film was explored as a flexible organic p-type thermoelectric leg using poly(3,4-ethylenedioxythiophene) (PEDOT) doped with tosylate. The PEDOT films were prepared through solution casting polymerization and rolled up for a roll-type leg. Due to the high flexibility, the roll-type PEDOT leg enabled easy contact to both top and bottom electrodes. Simulation on the dynamic heat transfer and convective cooling for a vertically roosted rod- and roll-type PEDOT leg showed that the temperature difference (ΔT) between the hot and cold sides of the leg was much higher in the roll than that of the rod. The PEDOT legs were integrated with n-type Bi2Te3 blocks, to give a 36-couple rigid-flexible thermoelectric generator (RF-TEG). The maximum output voltage from the 36-couple RF-TEG under a ΔT of 7.9 K was determined as 36.7 mV along with a high output power of 115 nW. A wearable RF-TEG was prepared upon the combination of the 36-couple RF-TEG with an arm warmer, to afford an output voltage of 10.6 mV, which was generated constantly and steadily from human wrist heat.

Effort, success, and nonuse determine arm choice

PubMed Central

Xiao, Yupeng; Kim, Sujin; Yoshioka, Toshinori; Gordon, James; Osu, Rieko

2015-01-01

How do humans choose one arm or the other to reach single targets in front of the body? Current theories of reward-driven decisionmaking predict that choice results from a comparison of “action values,” which are the expected rewards for possible actions in a given state. In addition, current theories of motor control predict that in planning arm movements, humans minimize an expected motor cost that balances motor effort and endpoint accuracy. Here, we test the hypotheses that arm choice is determined by comparison of action values comprising expected effort and expected task success for each arm, as well as a handedness bias. Right-handed subjects, in either a large or small target condition, were first instructed to use each hand in turn to shoot through an array of targets and then to choose either hand to shoot through the same targets. Effort was estimated via inverse kinematics and dynamics. A mixed-effects logistic-regression analysis showed that, as predicted, both expected effort and expected success predicted choice, as did arm use in the preceding trial. Finally, individual parameter estimation showed that the handedness bias correlated with mean difference between right- and left-arm success, leading to overall lower use of the left arm. We discuss our results in light of arm nonuse in individuals' poststroke. PMID:25948869

Software-recorded and self-reported duration of computer use in relation to the onset of severe arm-wrist-hand pain and neck-shoulder pain.

PubMed

Ijmker, Stefan; Huysmans, Maaike A; van der Beek, Allard J; Knol, Dirk L; van Mechelen, Willem; Bongers, Paulien M; Blatter, Birgitte M

2011-07-01

In both science and media, the adverse effects of a long duration of computer use at work on musculoskeletal health have long been debated. Until recently, the duration of computer use was mainly measured by self-reports, and studies using more objective measures, such as software-recorded computer duration, were lacking. The objective of this study was to examine the association between duration of computer use at work, measured with software and self-reports, and the onset of severe arm-wrist-hand and neck-shoulder symptoms. A 2-year follow-up study was conducted between 2004 and 2006 among 1951 office workers in The Netherlands. Self-reported computer duration and other risk factors were collected at baseline and at 1-year follow-up. Computer use at work was recorded continuously with computer software for 1009 participants. Outcome questionnaires were obtained at baseline and every 3 months during follow-up. Cases were identified based on the transition within 3 months of no or minor symptoms to severe symptoms. Self-reported duration of computer use was positively associated with the onset of both arm-wrist-hand (RR 1.9, 95% CI 1.1 to 3.1 for more than 4 h/day of total computer use at work) and neck-shoulder symptoms (RR 1.5, 95% CI 1.1 to 2.0 for more than 4 h/day of mouse use at work). The recorded duration of computer use did not show any statistically significant association with the outcomes. In the present study, no association was found between the software-recorded duration of computer use at work and the onset of severe arm-wrist-hand and neck-shoulder symptoms using an exposure window of 3 months. In contrast, a positive association was found between the self-reported duration of computer use at work and the onset of severe arm-wrist-hand and neck-shoulder symptoms. The different findings for recorded and self-reported computer duration could not be explained satisfactorily.

The effect of sitting and calf activity on leg fluid and snoring.

PubMed

Singh, Bhajan; Yadollahi, Azadeh; Lyons, Owen; Alshaer, Hisham; Bradley, T Douglas

2017-06-01

Prolonged sitting may promote leg fluid retention that redistributes to the neck during sleep and contributes to snoring. This could be attenuated by calf activity while sitting. In 16 healthy non-obese subjects we measured leg fluid volume (LFV) below the knees using bioelectrical impedance while sitting for 4h, snoring using a portable BresoDx™ device, and Mallampati grade. Using a double cross-over study design, subjects were randomized to one of two arms and crossed-over one week later: control arm - no calf exercise while sitting; intervention arm - calf contraction against a pedal resistance while sitting. The effects of sitting±calf activity on LFV and snoring were compared. We found that LFV increased by 216±101.0ml (p<0.0001) after sitting. Calf activity while sitting attenuated LFV by 53.8ml (p<0.0001) and, in all five subjects with severe upper airway narrowing (Mallampati grade IV), reduced snoring duration (from 357±132.9 to 116.2±72.1s/h, p=0.02) suggesting reduced overnight rostral fluid shift to the neck. Copyright © 2017 Elsevier B.V. All rights reserved.

The sensitivity, specificity and reliability of the GALS (gait, arms, legs and spine) examination when used by physiotherapists and physiotherapy students to detect rheumatoid arthritis.

PubMed

Beattie, Karen A; Macintyre, Norma J; Pierobon, Jessica; Coombs, Jennifer; Horobetz, Diana; Petric, Alexis; Pimm, Mara; Kean, Walter; Larché, Maggie J; Cividino, Alfred

2011-09-01

To evaluate the sensitivity, specificity and reliability of the gait, arms, legs and spine (GALS) examination to detect signs and symptoms of rheumatoid arthritis when used by physiotherapy students and physiotherapists. Two physiotherapy students and two physiotherapists were trained to perform the GALS examination by viewing an instructional DVD and attending a workshop. Two rheumatologists familiar with the GALS examination also participated in the workshop. All healthcare professionals performed the GALS examination on 25 participants with rheumatoid arthritis recruited through a rheumatology practice and 23 participants without any arthritides recruited from a primary care centre. Each participant was assessed by one rheumatologist, one physiotherapist and one physiotherapy student. Abnormalities of gait, arms, legs and spine, including their location and description, were recorded, along with whether or not a diagnosis of rheumatoid arthritis was suspected. Healthcare professionals understood the study's objective to be their agreement on GALS findings and were unaware that half of the participants had rheumatoid arthritis. Sensitivity, specificity and likelihood ratios were calculated to determine the ability of the GALS examination to screen for rheumatoid arthritis. Using rheumatologists' findings on the study day as the standard for comparison, sensitivity and specificity were 71 to 86% and 69 to 93%, respectively. Positive likelihood ratios ranged from 2.74 to 10.18, while negative likelihood ratios ranged from 0.21 to 0.38. The GALS examination may be a useful tool for physiotherapists to rule out rheumatoid arthritis in a direct access setting. Differences in duration and type of experience of each healthcare professional may contribute to the variation in results. The merits of introducing the GALS examination into physiotherapy curricula and practice should be explored. Copyright © 2010 Chartered Society of Physiotherapy. Published by Elsevier Ltd

Cross-cultural adaptation and clinical evaluation of a Korean version of the disabilities of arm, shoulder, and hand outcome questionnaire (K-DASH).

PubMed

Lee, Joo-Yup; Lim, Jae-Young; Oh, Joo Han; Ko, Young-Mi

2008-01-01

We developed a Korean version of the disabilities of arm, shoulder, and hand outcome questionnaire (K-DASH) by performing cross-cultural adaptation and evaluated the reliability and validity of the K-DASH. The K-DASH, SF-36, and Visual Analog Scale (VAS) for pain were administered to 161 patients with arm, shoulder, and hand problems. The internal consistency of the disability/symptom scores of the K-DASH was high (Cronbach's alpha 0.94). The retest assessed 131 of the 161 patients. The intraclass correlation coefficient was 0.91. The construct validity was evaluated using the correlations between the K-DASH and the SF-36 and VAS. The physical and mental component summary scales of the SF-36 and the VAS at rest and during activity were significantly correlated with the DASH disability/symptom scores. Despite the linguistic and cultural differences, the reliability and validity of the K-DASH were just as excellent as those of the original DASH.

A prognostic scoring system for arm exercise stress testing.

PubMed

Xie, Yan; Xian, Hong; Chandiramani, Pooja; Bainter, Emily; Wan, Leping; Martin, Wade H

2016-01-01

Arm exercise stress testing may be an equivalent or better predictor of mortality outcome than pharmacological stress imaging for the ≥50% for patients unable to perform leg exercise. Thus, our objective was to develop an arm exercise ECG stress test scoring system, analogous to the Duke Treadmill Score, for predicting outcome in these individuals. In this retrospective observational cohort study, arm exercise ECG stress tests were performed in 443 consecutive veterans aged 64.1 (11.1) years. (mean (SD)) between 1997 and 2002. From multivariate Cox models, arm exercise scores were developed for prediction of 5-year and 12-year all-cause and cardiovascular mortality and 5-year cardiovascular mortality or myocardial infarction (MI). Arm exercise capacity in resting metabolic equivalents (METs), 1 min heart rate recovery (HRR) and ST segment depression ≥1 mm were the stress test variables independently associated with all-cause and cardiovascular mortality by step-wise Cox analysis (all p<0.01). A score based on the relation HRR (bpm)+7.3×METs-10.5×ST depression (0=no; 1=yes) prognosticated 5-year cardiovascular mortality with a C-statistic of 0.81 before and 0.88 after adjustment for significant demographic and clinical covariates. Arm exercise scores for the other outcome end points yielded C-statistic values of 0.77-0.79 before and 0.82-0.86 after adjustment for significant covariates versus 0.64-0.72 for best fit pharmacological myocardial perfusion imaging models in a cohort of 1730 veterans who were evaluated over the same time period. Arm exercise scores, analogous to the Duke Treadmill Score, have good power for prediction of mortality or MI in patients who cannot perform leg exercise.

Comparison between the C-leg microprocessor-controlled prosthetic knee and non-microprocessor control prosthetic knees: a preliminary study of energy expenditure, obstacle course performance, and quality of life survey.

PubMed

Seymour, Ron; Engbretson, Brenda; Kott, Karen; Ordway, Nathaniel; Brooks, Gary; Crannell, Jessica; Hickernell, Elise; Wheeler, Katie

2007-03-01

This study investigated energy expenditure and obstacle course negotiation between the C-leg and various non-microprocessor control (NMC) prosthetic knees and compared a quality of life survey (SF-36v2) of use of the C-leg to national norms. Thirteen subjects with unilateral limb loss (12 with trans-femoral and one with a knee disarticulation amputation) participated in the study. The mean age was 46 years, range 30-75. Energy expenditure using both the NMC and C-leg prostheses was measured at self-selected typical and fast walking paces on a motorized treadmill. Subjects were also asked to walk through a standardized walking obstacle course carrying a 4.5 kg (10 lb) basket and with hands free. Finally, the SF-36v2 was completed for subjects while using the C-leg. Statistically significant differences were found in oxygen consumption between prostheses at both typical and fast paces with the C-leg showing decreased values. Use of the C-leg resulted in a statistically significant decrease in the number of steps and time to complete the obstacle course. Scores on a quality of life index for subjects using the C-leg were above the mean for norms for limitation in the use of an arm or leg, equal to the mean for the general United States population for the physical component score and were above this mean for the mental component score. Based on oxygen consumption and obstacle course findings, the C-leg when compared to the NMC prostheses may provide increased functional mobility and ease of performance in the home and community environment. Questionnaire results suggest a minimal quality of life impairment when using a C-leg for this cohort of individuals with amputation.

Inconsistency between simultaneous blood pressure measurements in the arm, forearm, and leg in anesthetized children.

PubMed

Keidan, Ilan; Sidi, Avner; Ben-Menachem, Erez; Tene, Yael; Berkenstadt, Haim

2014-02-01

To determine the accuracy and precision of simultaneous noninvasive blood pressure (NIBP) measurement in the arm, forearm, and ankle in anesthetized children. Prospective, randomized study. University medical center. 101 ASA physical status 1 and 2 children (aged 1-8 yrs) scheduled for elective surgery with general anesthesia. Simultaneous NIBP measurements were recorded at the arm, forearm, and ankle at 5-minute intervals. The systolic blood pressure difference between the arm-forearm or the arm-ankle was within the ± 10% range in 63% and 29% of measurements, and within the ± 20% range in 85% and 67% of measurements, respectively. The diastolic blood pressure difference between the arm-forearm or the arm-ankle was within the ± 10% range in 42% and 44% and within the ± 20% range in 67% and 74% of measurements, respectively. In patients in whom the initial three NIBP measurements were within the ± 20% range between the forearm and arm, 86% of the subsequent measurements were also within that limit. Forearm and ankle NIBP measurements are unreliable and inconsistent with NIBP measured in the arm of anesthetized children. These alternative BP measurement sites are not reliable in accuracy (comparison with reference "gold" standard) and precision (reproducibility). Copyright © 2014 Elsevier Inc. All rights reserved.

Rotational effect of buoyancy in frontcrawl: Does it really cause the legs to sink?

PubMed

Yanai, T

2001-02-01

The purposes of this study were to quantify the rotational effect of buoyant force (buoyant torque) during the performance of front crawl and to reexamine the mechanics of horizontal alignment of the swimmers. Three-dimensional videography was used to measure the position and orientation of the body segments of 11 competitive swimmers performing front crawl stroke at a sub-maximum sprinting speed. The dimensions of each body segment were defined mathematically to match the body segment parameters (mass, density, and centroid position) reported in the literature. The buoyant force and torque were computed for every video-field (60fields/s), assuming that the water surface followed a sine curve along the length of the swimmer. The average buoyant torque over the stroke cycle (mean=22Nm) was directed to raise the legs and lower the head, primarily because the recovery arm and a part of the head were lifted out of the water and the center of buoyancy shifted toward the feet. This finding contradicts the prevailing speculation that buoyancy only causes the legs to sink throughout the stroke cycle. On the basis of a theoretical analysis of the results, it is postulated that the buoyant torque, and perhaps the forces generated by kicks, function to counteract the torque generated by the hydrodynamic forces acting on the hands, so as to maintain the horizontal alignment of the body in front crawl.

Role of contralesional hemisphere in paretic arm reaching in patients with severe arm paresis due to stroke: A preliminary report.

PubMed

Mohapatra, Sambit; Harrington, Rachael; Chan, Evan; Dromerick, Alexander W; Breceda, Erika Y; Harris-Love, Michelle

2016-03-23

Stroke is highly prevalent and a leading cause of serious, long-term disability among American adults. Impaired movement (i.e. paresis) of the stroke-affected arm is a major contributor to post-stroke disability, yet the mechanisms of upper extremity motor recovery are poorly understood, particularly in severely impaired patients who lack hand function. To address this problem, we examined the functional relevance of the contralesional hemisphere in paretic arm motor performance in individuals with severe arm paresis. Twelve individuals with severe stroke-induced arm paresis (Upper Extremity Fugl-Meyer Assessment=17.1 ± 8.5; maximum score=66) participated in the study. Participants performed a reaching response time task with their paretic arm. At varying time intervals following a 'Go' cue, a pair of transcranial magnetic stimulation (TMS) pulses were delivered to contralesional hemisphere primary motor (M1) or dorsal pre-motor cortex (PMd) to momentarily disrupt the pattern of neural firing. Response time components and hand-path characteristics were compared across the 2 sites for trials with and without TMS disruption. There was no significant effect of TMS disruption on overall Response time or Reaction time, but Movement time was significantly longer (i.e. slower) with disruption of the contralesional hemisphere (p=0.015), regardless of which area was stimulated. Peak hand-path velocity and hand-path smoothness were also significantly lower (p=0.005 and p<0.0001, respectively) with TMS disruption of the contralesional hemisphere. The data from this study provide evidence supporting a functionally relevant role of contralesional hemisphere motor areas in paretic arm reaching movements in individuals with severe post-stroke arm impairment. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Work disability after diagnosis of hand-arm vibration syndrome.

PubMed

Sauni, Riitta; Toivio, Pauliina; Pääkkönen, Rauno; Malmström, Jari; Uitti, Jukka

2015-11-01

Our aim was to study the course of vasospastic and sensorineural symptoms after the clinical diagnosis of hand-arm vibration syndrome (HAVS), and the association of current HAVS symptoms with occupational status, self-evaluation of health, quality of life, and work ability. We gathered all HAVS cases diagnosed at the Finnish Institute of Occupational Health in Helsinki and Tampere during 1990-2008. A questionnaire was sent to all these patients (n = 241). Altogether 149 of them (62 %) returned the questionnaire. Cumulative lifelong vibration exposure was evaluated on the basis of the data in the patient files. On average, 8.5 years after the diagnosis of HAVS, approximately one-third of the patients reported improvement in symptoms of vibration-induced white finger (VWF) and the sensorineural symptoms. Young age and shorter exposure time were associated with improvement in VWF symptoms (p = 0.033 and p < 0.001, respectively). Persistent or deteriorated symptoms of both VWF and sensorineural symptoms were associated with lowered work ability, quality of life (EQ-5D), and general health, also after adjusting for age, smoking, and diseases other than HAVS. The patients' own prediction of work ability in 2 years was more negative if the VWF symptoms or sensorineural symptoms had continued after diagnosis of HAVS (p = 0.065 and p = 0.001, respectively). Our results suggest that in about two-thirds of the patients, the HAVS symptoms may stabilize or deteriorate in the follow-up. Considering the effects on work ability, timely prevention measures should be taken more actively to help patients continue their working careers.

Biomechanical study on axillary crutches during single-leg swing-through gait.

PubMed

Goh, J C; Toh, S L; Bose, K

1986-08-01

This paper describes a kinetic and kinematic study on axillary crutches during one-leg swing-through gait. The primary objective is to evaluate the interplay of forces at the crutch and body interfaces and to relate them in the understanding of problems associated with the use of axillary crutches. Ten normal adult male subjects with simulated left leg impairment participated in the study. For data acquisition, the VICON kinematic system, a Kistler force plate and an instrumented crutch (with force transducers at the two upper struts close to the axillary bar and one near the crutch tip) were used. Results showed that the peak ground reaction force on the weight-bearing leg during lower limb stance increased by 21.6 percent bodyweight. The peak reaction force transmitted to the arm during crutch stance was 44.4 percent bodyweight. These increased loadings could be detrimental to patients with unsound weight-bearing leg and upper extremities respectively. When the crutches were used incorrectly, 34 percent bodyweight was carried by the underarm. This could cause undue pressure over the neurovascular structures at the axillary region.

Novel diffusion tensor imaging technique reveals developmental streamline volume changes in the corticospinal tract associated with leg motor control

PubMed Central

Kamson, David O.; Juhász, Csaba; Chugani, Harry T.; Jeong, Jeong-Won

2014-01-01

Background Diffusion tensor imaging (DTI) has expanded our knowledge of corticospinal tract (CST) anatomy and development. However, previous developmental DTI studies assessed the CST as a whole, overlooking potential differences in development of its components related to control of the upper and lower extremities. The present cross-sectional study investigated age-related changes, side and gender differences in streamline volume of the leg- and hand-related segments of the CST in children. Subjects and methods DTI data of 31 children (1–14years; mean age: 6±4years; 17 girls) with normal conventional MRI were analyzed. Leg- and hand-related CST streamline volumes were quantified separately, using a recently validated novel tractography approach. CST streamline volumes on both sides were compared between genders and correlated with age. Results Higher absolute streamline volumes were found in the left leg-related CST compared to the right (p=0.001) without a gender effect (p=0.4), whereas no differences were found in the absolute hand-related CST volumes (p>0.4). CST leg-related streamline volumes, normalized to hemispheric white matter volumes, declined with age in the right hemisphere only (R=−.51; p=0.004). Absolute leg-related CST streamline volumes showed similar, but slightly weaker correlations. Hand-related absolute or normalized CST streamline volumes showed no age-related variations on either side. Conclusion These results suggest differential development of CST segments controlling hand vs. leg movements. Asymmetric volume changes in the lower limb motor pathway may be secondary to gradually strengthening left hemispheric dominance and is consistent with previous data suggesting that footedness is a better predictor of hemispheric lateralization than handedness. PMID:25027193

Pediatric restless legs syndrome: analysis of symptom descriptions and drawings.

PubMed

Picchietti, Daniel L; Arbuckle, Robert A; Abetz, Linda; Durmer, Jeffrey S; Ivanenko, Anna; Owens, Judith A; Croenlein, Jens; Allen, Richard P; Walters, Arthur S

2011-11-01

The specific aims of this study were to collect and analyze detailed symptom descriptions from patients with pediatric restless legs syndrome, ages 6 to 17 years, as well as assess symptom impact and the usefulness of drawings. Trained qualitative interviewers conducted face-to-face audio-recorded interviews of children and adolescents who met criteria for definite restless legs syndrome. Thirty-three patients in 3 age groups used 16 different categories of descriptors for restless legs sensations, with a mean of 3 or more categories used per patient in each age group. "Need to move/kick," "pain/hurts," "uncomfortable/cannot get comfortable," and "like bugs or ants/crawling" were the most common descriptors. Two-thirds reported daytime sensations, and nearly half had arm involvement. They described impact on sleep, cognitive function, and affect. Drawings provided useful diagnostic information. These detailed empirical data will be useful in clinical practice, as well as in the development of formal diagnostic tools and severity measures.

Novel diffusion tensor imaging technique reveals developmental streamline volume changes in the corticospinal tract associated with leg motor control.

PubMed

Kamson, David O; Juhász, Csaba; Chugani, Harry T; Jeong, Jeong-Won

2015-04-01

Diffusion tensor imaging (DTI) has expanded our knowledge of corticospinal tract (CST) anatomy and development. However, previous developmental DTI studies assessed the CST as a whole, overlooking potential differences in development of its components related to control of the upper and lower extremities. The present cross-sectional study investigated age-related changes, side and gender differences in streamline volume of the leg- and hand-related segments of the CST in children. DTI data of 31 children (1-14 years; mean age: 6±4 years; 17 girls) with normal conventional MRI were analyzed. Leg- and hand-related CST streamline volumes were quantified separately, using a recently validated novel tractography approach. CST streamline volumes on both sides were compared between genders and correlated with age. Higher absolute streamline volumes were found in the left leg-related CST compared to the right (p=0.001) without a gender effect (p=0.4), whereas no differences were found in the absolute hand-related CST volumes (p>0.4). CST leg-related streamline volumes, normalized to hemispheric white matter volumes, declined with age in the right hemisphere only (R=-.51; p=0.004). Absolute leg-related CST streamline volumes showed similar, but slightly weaker correlations. Hand-related absolute or normalized CST streamline volumes showed no age-related variations on either side. These results suggest differential development of CST segments controlling hand vs. leg movements. Asymmetric volume changes in the lower limb motor pathway may be secondary to gradually strengthening left hemispheric dominance and is consistent with previous data suggesting that footedness is a better predictor of hemispheric lateralization than handedness. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Aesthesiometric threshold changes over the course of a workshift in miners exposed to hand-arm vibration.

PubMed Central

Haines, T; Chong, J; Verrall, A B; Julian, J; Bernholz, C; Spears, R; Muir, D C

1988-01-01

The objective of this study was to investigate whether aesthesiometric threshold changes occur over the course of a workshift in vibration exposed hard rock miners relative to workers unexposed to vibration during the shift. The subjects were 99 miners and 40 smelter workers; four subjects declined to participate and nine were excluded from the analysis because of apparent failure to comprehend the testing procedure. Two point discrimination and depth sense aesthesiometry were conducted at the beginning and at the end of the workshift in all digits of both hands excluding the thumbs. In addition to the use of a vibrating tool during the shift, age, digital temperature, signs of arm injury, presence of fingertip callus, and handedness were documented. In the analysis the difference between postshift and preshift readings was studied in relation to these variables, particularly exposure to the jackleg drill during the shift. With the exception of exposure of the jackleg drill, no associations were observed between these variables and change over the workshift in aesthesiometric results, on both unadjusted comparison of means and backward elimination regression analysis. A statistically significant association, however, was found between the use of a jackleg drill and change in two point discrimination and in depth sense aesthesiometric results over the course of the shift, for the right hand. Evidence of the occurrence of a learning effect, particularly for two point discrimination aesthesiometry, was observed. The occurrence of an effect in the right, but not the left, hand reflects dominant handedness and relatively greater vibration exposure in the right hand in our subjects. This study supports the incorporation of an exposure free interval before aesthesiometric testing of vibration exposed workers. PMID:3342191

Nailfold capillary morphological characteristics of hand-arm vibration syndrome: a cross-sectional study

PubMed Central

Chen, QingSong; Chen, GuiPing; Xiao, Bin; Lin, HanSheng; Qu, HongYing; Zhang, DanYing; Shi, MaoGong; Lang, Li; Yang, Bei; Yan, MaoSheng

2016-01-01

Objective The purpose of this study was to investigate the characteristics of nailfold capillaroscopy associated with hand-arm vibration syndrome (HAVS). Methods In total, 113 male gold miners were recruited: 35 workers who were chronically exposed to vibration and developed vibration-induced white finger were defined as the HAVS group, 39 workers who were exposed to vibration but did not have HAVS were classified as the vibration-exposed controls (VEC) group, and 39 workers without vibration exposure were categorised as the non-VEC (NVEC) group. Video capillaroscopy was used to capture images of the 2nd, 3rd and 4th fingers of both hands. The following nailfold capillary characteristics were included: number of capillaries/mm, avascular areas, haemorrhages and enlarged capillaries. The experiments were carried out in the same winter. All characteristics were evaluated under blinded conditions. Results Significant differences in all morphological characteristics existed between the groups (p<0.05). Avascular areas in the HAVS, VEC and NVEC groups appeared in 74.3%, 43.6% and 25.0% of participants, respectively. A higher percentage of participants had haemorrhages in the HAVS group (65.7%) compared with the other groups (VEC: 7.7% and NVEC: 7.5%). The number of capillaries/mm, input limb width, output limb width, apical width, and ratio of output limb and input limb all had more than 70% sensitivity or specificity of their cut-off value. Conclusions Nailfold capillary characteristics, especially the number of capillaries/mm, avascular areas, haemorrhages, output limb width, input limb width and apical width alterations, revealed significant associations with HAVS. PMID:27888176

Design and Characterization of Hand Module for Whole-Arm Rehabilitation Following Stroke

PubMed Central

Masia, L.; Krebs, Hermano Igo; Cappa, P.; Hogan, N.

2009-01-01

In 1991, a novel robot named MIT-MANUS was introduced as a test bed to study the potential of using robots to assist in and quantify the neurorehabilitation of motor function. It introduced a new modality of therapy, offering a highly backdrivable experience with a soft and stable feel for the user. MIT-MANUS proved an excellent fit for shoulder and elbow rehabilitation in stroke patients, showing a reduction of impairment in clinical trials with well over 300 stroke patients. The greatest impairment reduction was observed in the group of muscles exercised. This suggests a need for additional robots to rehabilitate other target areas of the body. Previous work has expanded the planar MIT-MANUS to include an antigravity robot for shoulder and elbow, and a wrist robot. In this paper we present the “missing link”: a hand robot. It consists of a single-degree-of-freedom (DOF) mechanism in a novel statorless configuration, which enables rehabilitation of grasping. The system uses the kinematic configuration of a double crank and slider where the members are linked to stator and rotor; a free base motor, i.e., a motor having two rotors that are free to rotate instead of a fixed stator and a single rotatable rotor (dual-rotor statorless motor). A cylindrical structure, made of six panels and driven by the relative rotation of the rotors, is able to increase its radius linearly, moving or guiding the hand of the patients during grasping. This module completes our development of robots for the upper extremity, yielding for the first time a whole-arm rehabilitation experience. In this paper, we will discuss in detail the design and characterization of the device. PMID:20228969

Normative data for neuromuscular assessment of the hand-arm vibration syndrome and its retrospective applications in Korean male workers.

PubMed

Ahn, Ryeok; Yoo, Cheol-In; Lee, Hun; Sim, Chang-Sun; Sung, Joo Hyun; Yoon, Jae-Kook; Shin, Song-Woo

2013-10-01

The purpose of this study was to describe normative data for the neuromuscular assessments of the hand-arm vibration syndrome (HAVS) in Korean. Data for the vibrotactile perception threshold (VPT) at three frequencies (31.5, 125, and 250 Hz), the hand grip strength (HGS), the finger pinch strength (FPS), the finger tapping test, and the Purdue pegboard tests were collected from 120 male office workers aged 30-59 years with no prior history of regular use of handheld vibrating tools. The collected data were compared with the results of a similar study of shipbuilding workers in order to investigate the diagnostic utility of clinical test for HAVS. The mean VPT values indicate that no significant differences were observed between the dominant and non-dominant hands or between the index and little fingers. The age group of 30s was highly sensitive to vibration input with a peak in sensitivity at 125 Hz among all age groups. In neuromuscular performance, dominant hands are usually more accurate, dexterous, and functionally quicker than non-dominant hands. The index finger was superior to the little finger in the finger tapping counts (p < 0.05). Also, FPS was greater in the index finger than in the middle finger (p < 0.05). The HGS of dominant hands was significantly stronger than that of non-dominant hands (p < 0.05). When the normative data were compared with the data of shipyard workers exposed to vibration, there were statistically significant differences in VPT and neuromuscular functions. The current data can be used to evaluate HAVS in Korean male workers. Age is an important factor for VPT.

Active and Inactive Leg Hemodynamics during Sequential Single-Leg Interval Cycling.

PubMed

Gordon, Nicole; Abbiss, Chris R; Ihsan, Mohammed; Maiorana, Andrew J; Peiffer, Jeremiah J

2018-06-01

Leg order during sequential single-leg cycling (i.e., exercising both legs independently within a single session) may affect local muscular responses potentially influencing adaptations. This study examined the cardiovascular and skeletal muscle hemodynamic responses during double-leg and sequential single-leg cycling. Ten young healthy adults (28 ± 6 yr) completed six 1-min double-leg intervals interspersed with 1 min of passive recovery and, on a separate occasion, 12 (six with one leg followed by six with the other leg) 1-min single-leg intervals interspersed with 1 min of passive recovery. Oxygen consumption, heart rate, blood pressure, muscle oxygenation, muscle blood volume, and power output were measured throughout each session. Oxygen consumption, heart rate, and power output were not different between sets of single-leg intervals, but the average of both sets was lower than the double-leg intervals. Mean arterial pressure was higher during double-leg compared with sequential single-leg intervals (115 ± 9 vs 104 ± 9 mm Hg, P < 0.05) and higher during the initial compared with second set of single-leg intervals (108 ± 10 vs 101 ± 10 mm Hg, P < 0.05). The increase in muscle blood volume from baseline was similar between the active single leg and the double leg (267 ± 150 vs 214 ± 169 μM·cm, P = 0.26). The pattern of change in muscle blood volume from the initial to second set of intervals was significantly different (P < 0.05) when the leg was active in the initial (-52.3% ± 111.6%) compared with second set (65.1% ± 152.9%). These data indicate that the order in which each leg performs sequential single-leg cycling influences the local hemodynamic responses, with the inactive muscle influencing the stimulus experienced by the contralateral leg.

Asymmetric balance control between legs for quiet but not for perturbed stance.

PubMed

Vieira, Osvaldo; Coelho, Daniel Boari; Teixeira, Luis Augusto

2014-10-01

Interlateral performance asymmetry in upright balance control was evaluated in this investigation by comparing unipedal stance on the right versus the left leg. Participants were healthy young adults, hand-foot congruent preference for the right body side. Balance performance was evaluated in unperturbed quiet stance and in the recovery of balance stability following a mechanical perturbation induced by unexpected load release. Evaluation was made under availability of full sensory information, and under deprivation of vision combined with distortion of sensory inputs from the feet soles. Results from perturbed posture revealed that muscular response latency and postural sway were symmetric between the legs. Unipedal stance was more stable when the body was supported on the right as compared with the left leg. No interaction was found between leg and sensory condition. Our findings are interpreted as resulting from specialization of the sensorimotor system controlling the right leg for continuous low-magnitude postural adjustments, while corrections to large-scale stance sway are symmetrically controlled between body sides.

A virtual reality system for arm and hand rehabilitation

NASA Astrophysics Data System (ADS)

Luo, Zhiqiang; Lim, Chee Kian; Chen, I.-Ming; Yeo, Song Huat

2011-03-01

This paper presents a virtual reality (VR) system for upper limb rehabilitation. The system incorporates two motion track components, the Arm Suit and the Smart Glove which are composed of a range of the optical linear encoders (OLE) and the inertial measurement units (IMU), and two interactive practice applications designed for driving users to perform the required functional and non-functional motor recovery tasks. We describe the technique details about the two motion track components and the rational to design two practice applications. The experiment results show that, compared with the marker-based tracking system, the Arm Suit can accurately track the elbow and wrist positions. The repeatability of the Smart Glove on measuring the five fingers' movement can be satisfied. Given the low cost, high accuracy and easy installation, the system thus promises to be a valuable complement to conventional therapeutic programs offered in rehabilitation clinics and at home.

Normalisation of brain connectivity through compensatory behaviour, despite congenital hand absence.

PubMed

Hahamy, Avital; Sotiropoulos, Stamatios N; Henderson Slater, David; Malach, Rafael; Johansen-Berg, Heidi; Makin, Tamar R

2015-01-06

Previously we showed, using task-evoked fMRI, that compensatory intact hand usage after amputation facilitates remapping of limb representations in the cortical territory of the missing hand (Makin et al., 2013a). Here we show that compensatory arm usage in individuals born without a hand (one-handers) reflects functional connectivity of spontaneous brain activity in the cortical hand region. Compared with two-handed controls, one-handers showed reduced symmetry of hand region inter-hemispheric resting-state functional connectivity and corticospinal white matter microstructure. Nevertheless, those one-handers who more frequently use their residual (handless) arm for typically bimanual daily tasks also showed more symmetrical functional connectivity of the hand region, demonstrating that adaptive behaviour drives long-range brain organisation. We therefore suggest that compensatory arm usage maintains symmetrical sensorimotor functional connectivity in one-handers. Since variability in spontaneous functional connectivity in our study reflects ecological behaviour, we propose that inter-hemispheric symmetry, typically observed in resting sensorimotor networks, depends on coordinated motor behaviour in daily life.

A multipurpose modular drone with adjustable arms produced via the FDM additive manufacturing process

NASA Astrophysics Data System (ADS)

Brischetto, Salvatore; Ciano, Alessandro; Ferro, Carlo Giovanni

2016-07-01

The present paper shows an innovative multirotor Unmanned Aerial Vehicle (UAV) which is able to easily and quickly change its configuration. In order to satisfy this feature, the principal structure is made of an universal plate, combined with a circular ring, to create a rail guide able to host the arms, in a variable number from 3 to 8, and the legs. The arms are adjustable and contain all the avionic and motor drivers to connect the main structure with each electric motor. The unique arm design, defined as all-in-one, allows classical single rotor configurations, double rotor configurations and amphibious configurations including inflatable elements positioned at the bottom of the arms. The proposed multi-rotor system is inexpensive because of the few universal pieces needed to compose the platform which allows the creation of a kit. This modular kit allows to have a modular drone with different configurations. Such configurations are distinguished among them for the number of arms, number of legs, number of rotors and motors, and landing capability. Another innovation feature is the introduction of the 3D printing technology to produce all the structural elements. In this manner, all the pieces are designed to be produced via the Fused Deposition Modelling (FDM) technology using desktop 3D printers. Therefore, an universal, dynamic and economic multi-rotor UAV has been developed.

Technology-assisted training of arm-hand skills in stroke: concepts on reacquisition of motor control and therapist guidelines for rehabilitation technology design

PubMed Central

Timmermans, Annick AA; Seelen, Henk AM; Willmann, Richard D; Kingma, Herman

2009-01-01

Background It is the purpose of this article to identify and review criteria that rehabilitation technology should meet in order to offer arm-hand training to stroke patients, based on recent principles of motor learning. Methods A literature search was conducted in PubMed, MEDLINE, CINAHL, and EMBASE (1997–2007). Results One hundred and eighty seven scientific papers/book references were identified as being relevant. Rehabilitation approaches for upper limb training after stroke show to have shifted in the last decade from being analytical towards being focussed on environmentally contextual skill training (task-oriented training). Training programmes for enhancing motor skills use patient and goal-tailored exercise schedules and individual feedback on exercise performance. Therapist criteria for upper limb rehabilitation technology are suggested which are used to evaluate the strengths and weaknesses of a number of current technological systems. Conclusion This review shows that technology for supporting upper limb training after stroke needs to align with the evolution in rehabilitation training approaches of the last decade. A major challenge for related technological developments is to provide engaging patient-tailored task oriented arm-hand training in natural environments with patient-tailored feedback to support (re) learning of motor skills. PMID:19154570

Postural control of typical developing boys during the transition from double-leg stance to single-leg stance.

PubMed

Deschamps, Kevin; Staes, Filip; Peerlinck, Kathelijne; Van Geet, Kristel; Hermans, Cedric; Lobet, Sebastien

2017-02-01

Literature is lacking information about postural control performance of typically developing children during a transition task from double-leg stance to single-leg stance. The purpose of the present study was therefore to evaluate the clinical feasibility of a transition task in typical developing age groups as well as to study the correlation between associated balance measures and age.Thirty-three typically developing boys aged 6-20 years performed a standard transition task from DLS to SLS with eyes open (EO) and eyes closed (EC). Balance features derived from the center of pressure displacement captured by a single force platform were correlated with age on the one hand and considered for differences in the perspective of limb dominance on the other hand.All TDB (typically developing boys) were able to perform the transition task with EO. With respect to EC condition, all TDB from the age group 6-7 years and the youngest of the age group 8-12 years (N = 4) were unable to perform the task. No significant differences were observed between the balance measures of the dominant and non-dominant limbs.With respect to EO condition, correlation analyses indicated that time to new stability point (TNSP) as well as the sway measure after this TNSP were correlated with age (p < 0.0001). For the EC condition, only the anthropometrically scaled sway measure was found to be correlated (p = 0.03). The results provide additional insight into balance development in childhood and may serve as a useful basis for assessing balance impairments in higher functioning children with musculoskeletal problems. What is Known: • Reference data regarding postural balance of typically developing children during walking, running, sit-to-stand, and bipodal and unipodal stance has been well documented in the literature. • These reference data provided not only insight into the maturation process of the postural control system, but also served in diagnosing and managing functional

Leg CT scan

MedlinePlus

CAT scan - leg; Computed axial tomography scan - leg; Computed tomography scan - leg; CT scan - leg ... CT scan makes detailed pictures of the body very quickly. The test may help look for: An abscess ...

Leg kinematics and kinetics in landing from a single-leg hop for distance. A comparison between dominant and non-dominant leg.

PubMed

van der Harst, J J; Gokeler, A; Hof, A L

2007-07-01

Anterior cruciate ligament (ACL) deficiency can be a major problem for athletes and subsequent reconstruction of the ACL may be indicated if a conservative regimen has failed. After ACL reconstruction signs of abnormality in the use of the leg remain for a long time. It is expected that the landing after a single-leg hop for distance (horizontal hop) might give insight in the differences in kinematics and kinetics between uninjured legs and ACL-reconstructed legs. Before the ACL-reconstructed leg can be compared with the contralateral leg, knowledge of differences between legs of uninjured subjects is needed. Kinematic and kinetic variables of both legs were measured with an optoelectronic system and a force plate and calculated by inverse dynamics. The dominant leg (the leg with biggest horizontal hop distance) and the contralateral leg of nine uninjured subjects were compared. No significant differences were found in most of the kinematic and kinetic variables between dominant leg and contralateral leg of uninjured subjects. Only hop distance and hip extension angles differed significantly. This study suggests that there are no important differences between dominant leg and contralateral leg in healthy subjects. As a consequence, the uninvolved leg of ACL-reconstructed patients can be used as a reference. The observed variables of this study can be used as a reference of normal values and normal differences between legs in healthy subjects.

Neuromechanical considerations for incorporating rhythmic arm movement in the rehabilitation of walking

NASA Astrophysics Data System (ADS)

Klimstra, Marc D.; Thomas, Evan; Stoloff, Rebecca H.; Ferris, Daniel P.; Zehr, E. Paul

2009-06-01

We have extensively used arm cycling to study the neural control of rhythmic movements such as arm swing during walking. Recently rhythmic movement of the arms has also been shown to enhance and shape muscle activity in the legs. However, restricted information is available concerning the conditions necessary to maximally alter lumbar spinal cord excitability. Knowledge on the neuromechanics of a task can assist in the determination of the type, level, and timing of neural signals, yet arm swing during walking and arm cycling have not received a detailed neuromechanical comparison. The purpose of this research was to provide a combined neural and mechanical measurement approach that could be used to assist in the determination of the necessary and sufficient conditions for arm movement to assist in lower limb rehabilitation after stroke and spinal cord injury. Subjects performed three rhythmic arm movement tasks: (1) cycling (cycle); (2) swinging while standing (swing); and (3) swinging while treadmill walking (walk). We hypothesized that any difference in neural control between tasks (i.e., pattern of muscle activity) would reflect changes in the mechanical constraints unique to each task. Three-dimensional kinematics were collected simultaneously with force measurement at the hand and electromyography from the arms and trunk. All data were appropriately segmented to allow a comparison between and across conditions and were normalized and averaged to 100% movement cycle based on shoulder excursion. Separate mathematical principal components analysis of kinematic and neural variables was performed to determine common task features and muscle synergies. The results highlight important neural and mechanical features that distinguish differences between tasks. For example, there are considerable differences in the anatomical positions of the arms during each task, which relate to the moments experienced about the elbow and shoulder. Also, there are differences between

Test-retest reliability of neurophysiological tests of hand-arm vibration syndrome in vibration exposed workers and unexposed referents.

PubMed

Gerhardsson, Lars; Gillström, Lennart; Hagberg, Mats

2014-01-01

Exposure to hand-held vibrating tools may cause the hand-arm vibration syndrome (HAVS). The aim was to study the test-retest reliability of hand and muscle strength tests, and tests for the determination of thermal and vibration perception thresholds, which are used when investigating signs of neuropathy in vibration exposed workers. In this study, 47 vibration exposed workers who had been investigated at the department of Occupational and Environmental Medicine in Gothenburg were compared with a randomized sample of 18 unexposed subjects from the general population of the city of Gothenburg. All participants passed a structured interview, answered several questionnaires and had a physical examination including hand and finger muscle strength tests, determination of vibrotactile (VPT) and thermal perception thresholds (TPT). Two weeks later, 23 workers and referents, selected in a randomized manner, were called back for the same test-procedures for the evaluation of test-retest reliability. The test-retest reliability after a two week interval expressed as limits of agreement (LOA; Bland-Altman), intra-class correlation coefficients (ICC) and Pearson correlation coefficients was excellent for tests with the Baseline hand grip, Pinch-grip and 3-Chuck grip among the exposed workers and referents (N = 23: percentage of differences within LOA 91 - 100%; ICC-values ≥0.93; Pearson r ≥0.93). The test-retest reliability was also excellent (percentage of differences within LOA 96-100 %) for the determination of vibration perception thresholds in digits 2 and 5 bilaterally as well as for temperature perception thresholds in digits 2 and 5, bilaterally (percentage of differences within LOA 91 - 96%). For ICC and Pearson r the results for vibration perception thresholds were good for digit 2, left hand and for digit 5, bilaterally (ICC ≥ 0.84; r ≥0.85), and lower (ICC = 0.59; r = 0.59) for digit 2, right hand. For the latter two indices the test

Virtual Hand Illusion Induced by Visuomotor Correlations

PubMed Central

Sanchez-Vives, Maria V.; Spanlang, Bernhard; Frisoli, Antonio; Bergamasco, Massimo; Slater, Mel

2010-01-01

Background Our body schema gives the subjective impression of being highly stable. However, a number of easily-evoked illusions illustrate its remarkable malleability. In the rubber-hand illusion, illusory ownership of a rubber-hand is evoked by synchronous visual and tactile stimulation on a visible rubber arm and on the hidden real arm. Ownership is concurrent with a proprioceptive illusion of displacement of the arm position towards the fake arm. We have previously shown that this illusion of ownership plus the proprioceptive displacement also occurs towards a virtual 3D projection of an arm when the appropriate synchronous visuotactile stimulation is provided. Our objective here was to explore whether these illusions (ownership and proprioceptive displacement) can be induced by only synchronous visuomotor stimulation, in the absence of tactile stimulation. Methodology/Principal Findings To achieve this we used a data-glove that uses sensors transmitting the positions of fingers to a virtually projected hand in the synchronous but not in the asynchronous condition. The illusion of ownership was measured by means of questionnaires. Questions related to ownership gave significantly larger values for the synchronous than for the asynchronous condition. Proprioceptive displacement provided an objective measure of the illusion and had a median value of 3.5 cm difference between the synchronous and asynchronous conditions. In addition, the correlation between the feeling of ownership of the virtual arm and the size of the drift was significant. Conclusions/Significance We conclude that synchrony between visual and proprioceptive information along with motor activity is able to induce an illusion of ownership over a virtual arm. This has implications regarding the brain mechanisms underlying body ownership as well as the use of virtual bodies in therapies and rehabilitation. PMID:20454463

Age-dependent variations in the directional sensitivity of balance corrections and compensatory arm movements in man

PubMed Central

Allum, J H J; Carpenter, M G; Honegger, F; Adkin, A L; Bloem, B R

2002-01-01

We investigated the effects of ageing on balance corrections induced by sudden stance perturbations in different directions. Effects were examined in biomechanical and electromyographic (EMG) recordings from a total of 36 healthy subjects divided equally into three age groups (20–34, 35–55 and 60–75 years old). Perturbations consisted of six combinations of support-surface roll (laterally) and pitch (forward-backward) each with 7.5 deg amplitude (2 pure pitch, and 4 roll and pitch) delivered randomly. To reduce stimulus predictability further and to investigate scaling effects, perturbations were at either 30 or 60 deg s−1. In the legs, trunk and arms we observed age-related changes in balance corrections. The changes that appeared in the lower leg responses included smaller stretch reflexes in soleus and larger reflexes in tibialis anterior of the elderly compared with the young. For all perturbation directions, onsets of balance correcting responses in these ankle muscles were delayed by 20–30 ms and initially had smaller amplitudes (between 120–220 ms) in the elderly. This reduced early activity was compensated by increased lower leg activity after 240 ms. These EMG changes were paralleled by comparable differences in ankle torque responses, which were initially (after 160 ms) smaller in the elderly, but subsequently greater (after 280 ms). Findings in the middle-aged group were generally intermediate between the young and the elderly groups. Comparable results were obtained for the two different stimulus velocities. Stimulus-induced trunk roll, but not trunk pitch, changed dramatically with increasing age. Young subjects responded with early large roll movements of the trunk in the opposite direction to platform roll. A similarly directed but reduced amplitude of trunk roll was observed in the middle-aged. The elderly had very little initial roll modulation and also had smaller stretch reflexes in paraspinals. Balance-correcting responses (over 120�

Strategies for providing upper extremity amputees with tactile and hand position feedback--moving closer to the bionic arm.

PubMed

Riso, R R

1999-01-01

A continuing challenge for prostheses developers is to replace the sensory function of the hand. This includes tactile sensitivity such as finger contact, grip force, object slippage, surface texture and temperature, as well as proprioceptive sense. One approach is sensory substitution whereby an intact sensory system such as vision, hearing or cutaneous sensation elsewhere on the body is used as an input channel for information related to the prosthesis. A second technique involves using electrical stimulation to deliver sensor derived information directly to the peripheral afferent nerves within the residual limb. Stimulation of the relevant afferent nerves can ultimately come closest to restoring the original sensory perceptions of the hand, and to this end, researchers have already demonstrated some degree of functionality of the transected sensory nerves in studies with amputee subjects. This paper provides an overview of different types of nerve interface components and the advantages and disadvantages of employing each of them in sensory feedback systems. Issues of sensory perception, neurophysiology and anatomy relevant to hand sensation and function are discussed with respect to the selection of the different types of nerve interfaces. The goal of this paper is to outline what can be accomplished for implementing sensation into artificial arms in the near term by applying what is present or presently attainable technology.

Cardio-Respiratory Responses to Maximal Work During Arm and Bicycle Ergometry.

ERIC Educational Resources Information Center

Israel, Richard G.; Hardison, George T.

This study compared cardio-respiratory responses during maximal arm work using a Monarch Model 880 Rehab Trainer to cardio-respiratory responses during maximal leg work on a Monarch Model 850 Bicycle Ergometer. Subjects for the investigation were 17 male university students ranging from 18 to 28 years of age. The specific variables compared…

Exploring the relationship between stride, stature and hand size for forensic assessment.

PubMed

Guest, Richard; Miguel-Hurtado, Oscar; Stevenage, Sarah; Black, Sue

2017-11-01

Forensic evidence often relies on a combination of accurately recorded measurements, estimated measurements from landmark data such as a subject's stature given a known measurement within an image, and inferred data. In this study a novel dataset is used to explore linkages between hand measurements, stature, leg length and stride. These three measurements replicate the type of evidence found in surveillance videos with stride being extracted from an automated gait analysis system. Through correlations and regression modelling, it is possible to generate accurate predictions of stature from hand size, leg length and stride length (and vice versa), and to predict leg and stride length from hand size with, or without, stature as an intermediary variable. The study also shows improved accuracy when a subject's sex is known a-priori. Our method and models indicate the possibility of calculating or checking relationships between a suspect's physical measurements, particularly when only one component is captured as an accurately recorded measurement. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Nailfold capillary morphological characteristics of hand-arm vibration syndrome: a cross-sectional study.

PubMed

Chen, QingSong; Chen, GuiPing; Xiao, Bin; Lin, HanSheng; Qu, HongYing; Zhang, DanYing; Shi, MaoGong; Lang, Li; Yang, Bei; Yan, MaoSheng

2016-11-25

The purpose of this study was to investigate the characteristics of nailfold capillaroscopy associated with hand-arm vibration syndrome (HAVS). In total, 113 male gold miners were recruited: 35 workers who were chronically exposed to vibration and developed vibration-induced white finger were defined as the HAVS group, 39 workers who were exposed to vibration but did not have HAVS were classified as the vibration-exposed controls (VEC) group, and 39 workers without vibration exposure were categorised as the non-VEC (NVEC) group. Video capillaroscopy was used to capture images of the 2nd, 3rd and 4th fingers of both hands. The following nailfold capillary characteristics were included: number of capillaries/mm, avascular areas, haemorrhages and enlarged capillaries. The experiments were carried out in the same winter. All characteristics were evaluated under blinded conditions. Significant differences in all morphological characteristics existed between the groups (p<0.05). Avascular areas in the HAVS, VEC and NVEC groups appeared in 74.3%, 43.6% and 25.0% of participants, respectively. A higher percentage of participants had haemorrhages in the HAVS group (65.7%) compared with the other groups (VEC: 7.7% and NVEC: 7.5%). The number of capillaries/mm, input limb width, output limb width, apical width, and ratio of output limb and input limb all had more than 70% sensitivity or specificity of their cut-off value. Nailfold capillary characteristics, especially the number of capillaries/mm, avascular areas, haemorrhages, output limb width, input limb width and apical width alterations, revealed significant associations with HAVS. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Effects of waterproof covering on hand immersion tests using water at 10 degrees C, 12 degrees C and 15 degrees C for diagnosis of hand-arm vibration syndrome.

PubMed

Suizu, K; Harada, N

2005-05-01

To compare effects of waterproof covering on finger skin temperature (FST) and subjective hand pain during immersion tests using cold water at 10 degrees C, 12 degrees C and 15 degrees C. In the (Draft International Standard) of the International Organization for Standardization (ISO/DIS 14835-1), a water temperature of 12 degrees C and use of water covering are proposed. Six healthy male subjects took part in the immersion tests and immersed both hands into water at 10 degrees C, 12 degrees C and 15 degrees C for 5 min, repeatedly, with waterproof covering (polyethylene gloves) or without (bare hands). The FST data from middle fingers and subjective pain scores for hand pain were analyzed. Furthermore, the test with water at 12 degrees C was repeated to assess the repeatability of the test. The glove and water temperature factors for FST were significant at every minute from 1 min during immersion up to 2 min after recovery, showing higher values for waterproof covering than for bare hands and showing lowest values for water temperature of 10 degrees C and highest for 15 degrees C. The glove and water temperature factors for subjective pain score were significant at the 1-min and 2-min points during immersion, showing lower scores for waterproof covering than for bare hands and showing highest scores for water temperature of 10 degrees C and lowest for 15 degrees C. The results of the first and second tests using water of 12 degrees C showed no systematic difference in FST and hand pain between the tests, with a few exceptions. Subjective pain during the cold immersion test with polyethylene gloves and water at 12 degrees C can be reduced, while the differences in FST between water temperatures of 10 degrees C and 12 degrees C were small or not apparent at some points during immersion and recovery. The test also seems to be suitable for repeatability. Further investigation on hand-arm vibration syndrome (HAVS) patients to validate the use of the immersion test

Reliability of a Malay-translated questionnaire for use in a hand-arm vibration syndrome study in Malaysia.

PubMed

Su, T A; Hoe, V C W

2008-12-01

Validity and reliability of the information relating to hand-transmitted vibration exposure and vibration-related health outcome are very important for case finding in hand-arm vibration syndrome (HAVS) studies. In a local HAVS study among a group of construction workers in Kuala Lumpur, Malaysia, a questionnaire translated into Malay was created based on the Hand-transmitted Vibration Health Surveillance--Initial Questionnaire and Clinical Assessment, from Vibration Injury Network. This study was conducted to determine the reliability of standardised questions in the questionnaire used in the study. 15 subjects were selected randomly from the sampling frame of the HAVS study. Test-retest reliability was conducted on all items contained in parts 1-6 of the questionnaire and clinical assessment form, with an interval of 13-14 days between the first and second administration. Kappa coefficient and percentage agreement were calculated for all standardised questions. The kappa coefficient and percentage agreement for all standardised questions varied from -0.174 to 1.000 and 66.7 to 100.0 percent, respectively. The kappa coefficient for important questions related to current vibratory tool usage, tingling, numbness and hand grip weakness were 0.714, 0.432, -0.077 and -0.120, respectively, while the percentage agreement for current vibratory tool usage, finger colour change, tingling, numbness and hand grip weakness were 85.7 percent, 92.8 percent, 79.5 percent, 85.7 percent and 71.4 percent, respectively. Intra-rater reliability on the extent of vibration exposure was good, with the intra-class correlation coefficient (95 percent confidence interval) ranging from 0.786 (0.334-0.931) to 0.975 (0.923-0.992). Critical questions on vascular, neurological and musculoskeletal symptoms of HAVS were found to be reliable. The history on the extent of vibration exposure revealed good reliability when explored by the investigator alone. This questionnaire is considered reliable

Consequences of impact on arm (elbow and shoulder joints) caused by ball hitting, theoretical analysis

NASA Astrophysics Data System (ADS)

Negrea, Adina; Busuioceanu, Ioana Iuliana

2018-02-01

Present paper estimates the mechanics of the impact of a ball and a hand-arm, during the sports training using a classical model for the hand-arm system, avoiding the contribution of the coefficient of restitution. The results of this investigation are focused on the equations needed to find out theimpact reactions in elbow and shoulder joints, for different anthropometric data. Also, the computing of the position of mass centers and the moments of inertia for each constitutive part of hand-arm system is made.

The effect of differential training-based occupational therapy on hand and arm function in patients after stroke: Results of the pilot study.

PubMed

Repšaitė, Viktorija; Vainoras, Alfonsas; Berškienė, Kristina; Baltaduonienė, Daiva; Daunoravičienė, Algė; Sendžikaitė, Ernesta

2015-01-01

The aim of this study was to evaluate the effect of differential training-based occupational therapy on the recovery of arm function and to compare these data with the results obtained after conventional occupational therapy. A total of 27 patients who had suffered a cerebral infarction in the left brain hemisphere were recruited for the study. There were 9 men (33.33%) and 18 women (66.67%). All the patients had paresis of the right arm. The patients were divided into 2 groups: the control group comprised 15 patients who were given conventional occupational therapy (5 times per week) and the study group consisted of 12 patients who underwent conventional occupational therapy (3 times per week) along with occupational therapy based on differential training (2 times per week). In the control group, the mean performance time of only 2 tasks, i.e., flip cards and fold towel, improved significantly (P<0.05), while significant deterioration in the mean performance time of the task "lift can" was observed (P<0.05). In the study group, the mean performance time of all the tasks except for forearm to box (side), hand to box (front), and lift paperclip improved significantly (P<0.05), and no deterioration in arm function was observed. Both patients' groups improved arm function after occupational therapy sessions, but the patients who underwent conventional occupational therapy along with differential training-based occupational therapy recovered their arm function more effectively than their counterparts after conventional occupational therapy. Copyright © 2015 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

[Paraesthesia in the legs].

PubMed

Eisensehr, Ilonka

2007-10-18

Paraesthesia in the legs can have numerous causes. In addition to the restless legs syndrome, other primary causes include venous insufficiency in the leg, propriospinal myoclonus, nocturnal leg cramps, peripheral polyneuropathy that affects mostly the legs or neuroleptic drug-induced akathisia. Through detailed questioning of the patient, restless legs syndrome can be specifically distinguished from the other named differential diagnoses.

Disrupting Illicit Small Arms Trafficking in the Middle East

DTIC Science & Technology

2008-12-01

personal use and light weapons as weapons designed for use by a crew. Small arms include revolvers, self-loading pistols, rifles, sub- machine guns...assault rifles, and light machine guns. Light weapons include machine -guns, mortars, hand grenades, grenade launchers, portable anti-aircraft guns...71 David Atwood , Anne-Katherin Glatz, and Robert Muggah, Demanding Attention: Addressing the Dynamics of Small Arms Demand (Geneva: Small Arms

Rotationally Actuated Prosthetic Hand

NASA Technical Reports Server (NTRS)

Norton, William E.; Belcher, Jewell G., Jr.; Carden, James R.; Vest, Thomas W.

1991-01-01

Prosthetic hand attached to end of remaining part of forearm and to upper arm just above elbow. Pincerlike fingers pushed apart to degree depending on rotation of forearm. Simpler in design, simpler to operate, weighs less, and takes up less space.

Does Navigation Improve Accuracy of Placement of Pedicle Screws in Single-level Lumbar Degenerative Spondylolisthesis?: A Comparison Between Free-hand and Three-dimensional O-Arm Navigation Techniques.

PubMed

Boon Tow, Benjamin Phak; Yue, Wai Mun; Srivastava, Abhishek; Lai, Jenn Ming; Guo, Chang Ming; Wearn Peng, Benedict Chan; Chen, John L T; Yew, Andy K S; Seng, Chusheng; Tan, Seang Beng

2015-10-01

This was a prospective, nonrandomized study. To assess the accuracy of O-arm navigation-based pedicle screw insertion in lumbar degenerative spondylolisthesis and to compare it with free-hand pedicle screw insertion technique in matched population. O-arm navigation is latest in navigation technology that can provide real-time intraoperative images in 3 dimensions while placing the pedicle screws to improve intraoperative pedicle screw accuracy. Degenerative lumbar spondylolisthesis is a locally unstable pathology and placement of pedicle screws can cause increased rotation and translation of the vertebral body. However, is this motion detected by the tracker placed across the unstable segment, is a matter of debate. Inability to detect these positional changes can lead to pedicle perforation while inserting screws using navigation. No study has evaluated the role of O-arm navigation in this patient population. The study population was divided into 2 groups with 19 patients each, one comprising patients who underwent O-arm navigation-based pedicle screw insertion (group 1) and the other comprising patients who underwent free-hand pedicle screw insertion technique (group 2). A total of 152 pedicle screws were implanted in 38 patients for 1-level instrumented fusion for degenerative lumbar spondylolisthesis. Intraoperative 3-dimensional computed tomography scans using the O-arm were obtained for all patients after insertion of pedicle screws. The images were reviewed intraoperatively and postoperatively for the analysis of pedicle breaches. Assessments in either of the group included (i) accuracy of placement of screws; (ii) the rate and direction of perforation; and (iii) the number of segments the perforated screw was away from the navigation tracker. Mean age of patients in group 1 (O-arm navigation-assisted) was 60 years (SD 11.25; range, 37-73 y), whereas in group 2 (free-hand pedicle screw) was 62 years (SD 18.07; range, 36-90 y). Overall anatomic perforation

Novel actuation design of a gait trainer with shadow leg approach.

PubMed

Meuleman, Jos; Meuleman, Jos; van Asseldonk, Edwin H F; van der Kooij, Herman

2013-06-01

Robotic gait training has developed since the end of the 20(th) century, yet there is much room for improvement in the design of the robots. With the conventional exoskeleton structures, donning of patients in a gait trainer usually is a cumbersome process due to the need of joint alignments and normal walking is often hindered due to obstructed arm swing. Our goal was to design a gait training robots that overcomes these limitations. We propose a novel design in which these drawbacks are reduced to a great amount. By using a parallel structure behind the patient (shadow leg) that is connected to the patient joints with rods, little alignment is needed, the area lateral to the hip is left free, and thus arm swing is not obstructed. The construction is lightweight, because the actuators are mounted on a fixed base and the transmission of power is executed with light weight rods. An end stop in the shadow leg prevents hyper extension of the patient's knee. The relationship between motor displacement and human joint rotations is nonlinear. In this paper we derive the nonlinear relationships between motors and patient joints and verify these. calculations with a measurement. The device has been built, now tests with subjects are required to assess if subjects can indeed walk normally in the robot.

Multi-fingered robotic hand

NASA Technical Reports Server (NTRS)

Ruoff, Carl F. (Inventor); Salisbury, Kenneth, Jr. (Inventor)

1990-01-01

A robotic hand is presented having a plurality of fingers, each having a plurality of joints pivotally connected one to the other. Actuators are connected at one end to an actuating and control mechanism mounted remotely from the hand and at the other end to the joints of the fingers for manipulating the fingers and passing externally of the robot manipulating arm in between the hand and the actuating and control mechanism. The fingers include pulleys to route the actuators within the fingers. Cable tension sensing structure mounted on a portion of the hand are disclosed, as is covering of the tip of each finger with a resilient and pliable friction enhancing surface.

Interactive Design and Development of Real Arm Movements for Application in Rehabilitation

NASA Astrophysics Data System (ADS)

Rosman, Rafidah; Hadi, Muhammad Zaidan Abdul; Abu Bakar, Nurulliyana

2018-03-01

An interactive real arm movements for application in rehabilitation is designed and developed. The aim is to encourage hand paralysis patients performing their physical therapy by introducing games application in replacing conventional hand therapy module and methods. In this project, the accelerometer is used for tracking the orientation of the arm. As the arm moves, the values from x, y and z axis from the accelerometer changes and are being read by the Analog Inputs of the Arduino Board. After being read by the Analog Inputs of the Arduino Board, the 3D model moves as well. Solidworks software was used to modeled the hand in which the data is then transferred to Matlab/Simulink using SimMechanicalLink from Mathworks. Lastly, the sensor glove was programmed to work as a controller of games application in hand rehabilitation thus makes it an enjoyable therapy process.

Task driven optimal leg trajectories in insect-scale legged microrobots

NASA Astrophysics Data System (ADS)

Doshi, Neel; Goldberg, Benjamin; Jayaram, Kaushik; Wood, Robert

Origami inspired layered manufacturing techniques and 3D-printing have enabled the development of highly articulated legged robots at the insect-scale, including the 1.43g Harvard Ambulatory MicroRobot (HAMR). Research on these platforms has expanded its focus from manufacturing aspects to include design optimization and control for application-driven tasks. Consequently, the choice of gait selection, body morphology, leg trajectory, foot design, etc. have become areas of active research. HAMR has two controlled degrees-of-freedom per leg, making it an ideal candidate for exploring leg trajectory. We will discuss our work towards optimizing HAMR's leg trajectories for two different tasks: climbing using electroadhesives and level ground running (5-10 BL/s). These tasks demonstrate the ability of single platform to adapt to vastly different locomotive scenarios: quasi-static climbing with controlled ground contact, and dynamic running with un-controlled ground contact. We will utilize trajectory optimization methods informed by existing models and experimental studies to determine leg trajectories for each task. We also plan to discuss how task specifications and choice of objective function have contributed to the shape of these optimal leg trajectories.

Terminal Distribution of the Corticospinal Projection from the Hand/Arm Region of the Primary Motor Cortex to the Cervical Enlargement in Rhesus Monkey

PubMed Central

Morecraft, Robert J.; Ge, Jizhi; Stilwell-Morecraft, Kimberly S.; McNeal, David W.; Pizzimenti, Marc A.; Darling, Warren G.

2013-01-01

To further our understanding of the corticospinal projection (CSP) from the hand/arm representation of the primary motor cortex (M1), high-resolution anterograde tracing methodology and stereology were used to investigate the terminal distribution of this connection at spinal levels C5 to T1. The highest number of labeled terminal boutons occurred contralaterally (98%) with few ipsilaterally (2%). Contralaterally, labeled boutons were located within laminae I – X, with the densest distribution found in lamina VII and, to a lesser extent, laminae IX and VI. Fewer terminals were found in other contralateral laminae. Within lamina VII, terminal boutons were most prominent in the dorsomedial, dorsolateral and ventrolateral subsectors. Within lamina IX, the heaviest terminal labeling was distributed dorsally. Ipsilaterally, boutons were found in laminae V – X. The most pronounced distribution occurred in the dorsomedial and ventromedial sectors of lamina VII and fewer labeled boutons were located in other ipsilateral laminae. Segmentally, contralateral lamina VII labeling was highest at levels C5-C7. In contrast, lamina IX labeling was highest at C7-T1 and more widely dispersed amongst the quadrants at C8-T1. Our findings suggest dominant contralateral influence of the M1 hand/arm CSP, a contralateral innervation pattern in lamina VII supporting Kuypers (1982) conceptual framework of a “lateral motor system”, and a projection to lamina IX indicating significant influence on motoneurons innervating flexors acting on the shoulder and elbow rostrally (C5-C7), along with flexors, extensors, abductors and adductors acting on the digits, hand and wrist caudally (C8-T1). PMID:23840034

Effects of age, sex and arm on the precision of arm position sense-left-arm superiority in healthy right-handers.

PubMed

Schmidt, Lena; Depper, Lena; Kerkhoff, Georg

2013-01-01

Position sense is an important proprioceptive ability. Disorders of arm position sense (APS) often occur after unilateral stroke, and are associated with a negative functional outcome. In the present study we assessed horizontal APS by measuring angular deviations from a visually defined target separately for each arm in a large group of healthy subjects. We analyzed the accuracy and instability of horizontal APS as a function of age, sex and arm. Subjects were required to specify verbally the position of their unseen arm on a 0-90° circuit by comparing the current position with the target position indicated by a LED lamp, while the arm was passively moved by the examiner. Eighty-seven healthy subjects participated in the study, ranging from 20 to 77 years, subdivided into three age groups. The results revealed that APS was not a function of age or sex, but was significantly better in the non-dominant (left) arm in absolute errors (AE) but not in constant errors (CE) across all age groups of right-handed healthy subjects. This indicates a right-hemisphere superiority for left APS in right-handers and neatly fits to the more frequent and more severe left-sided body-related deficits in patients with unilateral stroke (i.e. impaired APS in left spatial neglect, somatoparaphrenia) or in individuals with abnormalities of the right cerebral hemisphere. These clinical issues will be discussed.

Effect of Tendon Vibration on Hemiparetic Arm Stability in Unstable Workspaces.

PubMed

Conrad, Megan O; Gadhoke, Bani; Scheidt, Robert A; Schmit, Brian D

2015-01-01

Sensory stimulation of wrist musculature can enhance stability in the proximal arm and may be a useful therapy aimed at improving arm control post-stroke. Specifically, our prior research indicates tendon vibration can enhance stability during point-to-point arm movements and in tracking tasks. The goal of the present study was to investigate the influence of forearm tendon vibration on endpoint stability, measured at the hand, immediately following forward arm movements in an unstable environment. Both proximal and distal workspaces were tested. Ten hemiparetic stroke subjects and 5 healthy controls made forward arm movements while grasping the handle of a two-joint robotic arm. At the end of each movement, the robot applied destabilizing forces. During some trials, 70 Hz vibration was applied to the forearm flexor muscle tendons. 70 Hz was used as the stimulus frequency as it lies within the range of optimal frequencies that activate the muscle spindles at the highest response rate. Endpoint position, velocity, muscle activity and grip force data were compared before, during and after vibration. Stability at the endpoint was quantified as the magnitude of oscillation about the target position, calculated from the power of the tangential velocity data. Prior to vibration, subjects produced unstable, oscillating hand movements about the target location due to the applied force field. Stability increased during vibration, as evidenced by decreased oscillation in hand tangential velocity.

Effect of Tendon Vibration on Hemiparetic Arm Stability in Unstable Workspaces

PubMed Central

Conrad, Megan O.; Gadhoke, Bani; Scheidt, Robert A.; Schmit, Brian D.

2015-01-01

Sensory stimulation of wrist musculature can enhance stability in the proximal arm and may be a useful therapy aimed at improving arm control post-stroke. Specifically, our prior research indicates tendon vibration can enhance stability during point-to-point arm movements and in tracking tasks. The goal of the present study was to investigate the influence of forearm tendon vibration on endpoint stability, measured at the hand, immediately following forward arm movements in an unstable environment. Both proximal and distal workspaces were tested. Ten hemiparetic stroke subjects and 5 healthy controls made forward arm movements while grasping the handle of a two-joint robotic arm. At the end of each movement, the robot applied destabilizing forces. During some trials, 70 Hz vibration was applied to the forearm flexor muscle tendons. 70 Hz was used as the stimulus frequency as it lies within the range of optimal frequencies that activate the muscle spindles at the highest response rate. Endpoint position, velocity, muscle activity and grip force data were compared before, during and after vibration. Stability at the endpoint was quantified as the magnitude of oscillation about the target position, calculated from the power of the tangential velocity data. Prior to vibration, subjects produced unstable, oscillating hand movements about the target location due to the applied force field. Stability increased during vibration, as evidenced by decreased oscillation in hand tangential velocity. PMID:26633892

Neural control of rhythmic arm cycling after stroke

PubMed Central

Loadman, Pamela M.; Hundza, Sandra R.

2012-01-01

Disordered reflex activity and alterations in the neural control of walking have been observed after stroke. In addition to impairments in leg movement that affect locomotor ability after stroke, significant impairments are also seen in the arms. Altered neural control in the upper limb can often lead to altered tone and spasticity resulting in impaired coordination and flexion contractures. We sought to address the extent to which the neural control of movement is disordered after stroke by examining the modulation pattern of cutaneous reflexes in arm muscles during arm cycling. Twenty-five stroke participants who were at least 6 mo postinfarction and clinically stable, performed rhythmic arm cycling while cutaneous reflexes were evoked with trains (5 × 1.0-ms pulses at 300 Hz) of constant-current electrical stimulation to the superficial radial (SR) nerve at the wrist. Both the more (MA) and less affected (LA) arms were stimulated in separate trials. Bilateral electromyography (EMG) activity was recorded from muscles acting at the shoulder, elbow, and wrist. Analysis was conducted on averaged reflexes in 12 equidistant phases of the movement cycle. Phase-modulated cutaneous reflexes were present, but altered, in both MA and LA arms after stroke. Notably, the pattern was “blunted” in the MA arm in stroke compared with control participants. Differences between stroke and control were progressively more evident moving from shoulder to wrist. The results suggest that a reduced pattern of cutaneous reflex modulation persists during rhythmic arm movement after stroke. The overall implication of this result is that the putative spinal contributions to rhythmic human arm movement remain accessible after stroke, which has translational implications for rehabilitation. PMID:22572949

Efficacy and cost-effectiveness of octenidine wound gel in the treatment of chronic venous leg ulcers in comparison to modern wound dressings.

PubMed

Hämmerle, Gilbert; Strohal, Robert

2016-04-01

The aim of this study was to determine the efficacy, safety and cost-effectiveness of an octenidine-based wound gel in the treatment of chronic venous leg ulcers. For this purpose, 49 wounds were treated with either modern wound-phase-adapted dressings alone (treatment arm 1; n = 17), octenidine wound gel plus modern wound-phase-adapted dressings (treatment arm 2; n = 17) or octenidine wound gel alone (treatment arm 3; n = 15). During the study period of 42 days with dressing changes every 3-5 days, wound healing characteristics and treatment costs of different dressings were analysed. Wound size reduction was significantly better (P = 0·028) in both octenidine wound gel treatment arms compared to modern dressings alone with total reductions of 14·6%, 64·1% and 96·2% in treatment arms 1-3. Early wound healing was merely observed under octenidine wound gel treatment (n = 9), whereby lowest treatment costs were generated by octenidine wound gel alone (€20·34/dressing change). As a result, the octenidine wound gel is cost-effective and well suitable for the treatment of chronic venous leg ulcers, considering both safety and promotion of wound healing. © 2014 The Authors. International Wound Journal © 2014 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Referral of sensation to an advanced humanoid robotic hand prosthesis.

PubMed

Rosén, Birgitta; Ehrsson, H Henrik; Antfolk, Christian; Cipriani, Christian; Sebelius, Fredrik; Lundborg, Göran

2009-01-01

Hand prostheses that are currently available on the market are used by amputees to only a limited extent, partly because of lack of sensory feedback from the artificial hand. We report a pilot study that showed how amputees can experience a robot-like advanced hand prosthesis as part of their own body. We induced a perceptual illusion by which touch applied to the stump of the arm was experienced from the artificial hand. This illusion was elicited by applying synchronous tactile stimulation to the hidden amputation stump and the robotic hand prosthesis in full view. In five people who had had upper limb amputations this stimulation caused referral touch sensation from the stump to the artificial hand, and the prosthesis was experienced more like a real hand. We also showed that this illusion can work when the amputee controls the movements of the artificial hand by recordings of the arm muscle activity with electromyograms. These observations indicate that the previously described "rubber hand illusion" is also valid for an advanced hand prosthesis, even when it has a robotic-like appearance.

Motor cortex hand area and speech: implications for the development of language.

PubMed

Meister, Ingo Gerrit; Boroojerdi, Babak; Foltys, Henrik; Sparing, Roland; Huber, Walter; Töpper, Rudolf

2003-01-01

Recently a growing body of evidence has suggested that a functional link exists between the hand motor area of the language dominant hemisphere and the regions subserving language processing. We examined the excitability of the hand motor area and the leg motor area during reading aloud and during non-verbal oral movements using transcranial magnetic stimulation (TMS). During reading aloud, but not before or afterwards, excitability was increased in the hand motor area of the dominant hemisphere. This reading effect was found to be independent of the duration of speech. No such effect could be found in the contralateral hemisphere. The excitability of the leg area of the motor cortex remained unchanged during reading aloud. The excitability during non-verbal oral movements was slightly increased in both hemispheres. Our results are consistent with previous findings and may indicate a specific functional connection between the hand motor area and the cortical language network.

Effects of training with a passive hand orthosis and games at home in chronic stroke: a pilot randomised controlled trial.

PubMed

Nijenhuis, Sharon M; Prange-Lasonder, Gerdienke B; Stienen, Arno Ha; Rietman, Johan S; Buurke, Jaap H

2017-02-01

To compare user acceptance and arm and hand function changes after technology-supported training at home with conventional exercises in chronic stroke. Secondly, to investigate the relation between training duration and clinical changes. A randomised controlled trial. Training at home, evaluation at research institute. Twenty chronic stroke patients with severely to mildly impaired arm and hand function. Participants were randomly assigned to six weeks (30 minutes per day, six days a week) of self-administered home-based arm and hand training using either a passive dynamic wrist and hand orthosis combined with computerised gaming exercises (experimental group) or prescribed conventional exercises from an exercise book (control group). Main outcome measures are the training duration for user acceptance and the Action Research Arm Test for arm and hand function. Secondary outcomes are the Intrinsic Motivation Inventory, Fugl-Meyer assessment, Motor Activity Log, Stroke Impact Scale and grip strength. The control group reported a higher training duration (189 versus 118 minutes per week, P = 0.025). Perceived motivation was positive and equal between groups ( P = 0.935). No differences in clinical outcomes over training between groups were found (P ⩾ 0.165). Changes in Box and Block Test correlated positively with training duration ( P = 0.001). Both interventions were accepted. An additional benefit of technology-supported arm and hand training over conventional arm and hand exercises at home was not demonstrated. Training duration in itself is a major contributor to arm and hand function improvements.

Comparison of stiffness and interface pressure during rest and exercise among various arm sleeves.

PubMed

Hirai, M; Niimi, K; Iwata, H; Sugimoto, I; Ishibashi, H; Ota, T; Nakamura, H

2010-08-01

To compare the interface pressure during rest and exercise among various kinds of arm sleeves. The interface pressure underneath nine different arm sleeves was measured during 10 maximal opening and closing movements of fingers using a pressure transducer (Air Pack Type Analyser) in 16 healthy volunteers. Furthermore, in order to evaluate the characteristics of each arm sleeve, the extensibility, stiffness and thickness were determined in vitro by several apparatuses. There was a significant correlation between stiffness and extensibility. The stiffness was significantly correlated with the pressure difference between muscle contraction and relaxation during exercise. The higher the value of stiffness, the greater the pressure amplitude during exercise. Short-stretch arm sleeves characterized with a high level stiffness, including thick round- and flat-knitted arm sleeves, are more beneficial for the augmentation of muscle pumping than long-stretch arm sleeves, in the same way as short-stretch bandages or stockings applied to the leg.

The effects of the arm swing on biomechanical and physiological aspects of roller ski skating.

PubMed

Hegge, Ann Magdalen; Ettema, Gertjan; de Koning, Jos J; Rognstad, Asgeir Bakken; Hoset, Martin; Sandbakk, Øyvind

2014-08-01

This study analyzed the biomechanical and physiological effects of the arm swing in roller ski skating, and compared leg-skating (i.e. ski skating without poles) using a pronounced arm swing (SWING) with leg-skating using locked arms (LOCKED). Sixteen elite male cross-country skiers performed submaximal stages at 10, 15 and 20kmh(-1) on a 2% inclined treadmill in the two techniques. SWING demonstrated higher peak push-off forces and a higher force impulse at all speeds, but a longer cycle length only at the highest speed (all P<.05), indicating a lower force effectiveness with SWING at the two lowest speeds. Additionally, the flexion-extension movement in the lower limbs was more pronounced for SWING. Oxygen uptake was higher for SWING at the two lowest speeds (both P<.05) without any differences in blood lactate. At the highest speed, oxygen uptake did not differ between SWING and LOCKED, but the RER, blood lactate and ventilation were lower with SWING (all P<.05). Taken together, these results demonstrate that utilizing the arm swing in roller ski skating increases the ski forces and aerobic energy cost at low and moderate speeds, whereas the greater forces at high speed lead to a longer cycle length and smaller anaerobic contribution. Copyright © 2014 Elsevier B.V. All rights reserved.

In a demanding task, three-handed manipulation is preferred to two-handed manipulation

NASA Astrophysics Data System (ADS)

Abdi, Elahe; Burdet, Etienne; Bouri, Mohamed; Himidan, Sharifa; Bleuler, Hannes

2016-02-01

Equipped with a third hand under their direct control, surgeons may be able to perform certain surgical interventions alone; this would reduce the need for a human assistant and related coordination difficulties. However, does human performance improve with three hands compared to two hands? To evaluate this possibility, we carried out a behavioural study on the performance of naive adults catching objects with three virtual hands controlled by their two hands and right foot. The subjects could successfully control the virtual hands in a few trials. With this control strategy, the workspace of the hands was inversely correlated with the task velocity. The comparison of performance between the three and two hands control revealed no significant difference of success in catching falling objects and in average effort during the tasks. Subjects preferred the three handed control strategy, found it easier, with less physical and mental burden. Although the coordination of the foot with the natural hands increased trial after trial, about two minutes of practice was not sufficient to develop a sense of ownership towards the third arm.

In a demanding task, three-handed manipulation is preferred to two-handed manipulation.

PubMed

Abdi, Elahe; Burdet, Etienne; Bouri, Mohamed; Himidan, Sharifa; Bleuler, Hannes

2016-02-25

Equipped with a third hand under their direct control, surgeons may be able to perform certain surgical interventions alone; this would reduce the need for a human assistant and related coordination difficulties. However, does human performance improve with three hands compared to two hands? To evaluate this possibility, we carried out a behavioural study on the performance of naive adults catching objects with three virtual hands controlled by their two hands and right foot. The subjects could successfully control the virtual hands in a few trials. With this control strategy, the workspace of the hands was inversely correlated with the task velocity. The comparison of performance between the three and two hands control revealed no significant difference of success in catching falling objects and in average effort during the tasks. Subjects preferred the three handed control strategy, found it easier, with less physical and mental burden. Although the coordination of the foot with the natural hands increased trial after trial, about two minutes of practice was not sufficient to develop a sense of ownership towards the third arm.

Rifampin

MedlinePlus

... lack of coordination difficulty concentrating confusion changes in behavior muscle weakness pain in the arms, hands, feet, or legs heartburn stomach cramps diarrhea gas painful or irregular menstrual periods vision changes Some ...

The Lindsay Leg Club: supporting the NHS to provide leg ulcer care.

PubMed

McKenzie, Morag

2013-06-01

Public health services will need to cope with additional demands due to an ageing society and the increasing prevalence of chronic conditions. Lower-limb ulceration is a long-term, life-changing condition and leg ulcer management can be challenging for nursing staff. The Lindsay Leg Club model is a unique partnership between community nurses, members and the local community, which provides quality of care and empowerment for patients with leg ulcers, while also supporting and educating nursing staff. The Leg Club model works in accord with core themes of Government and NHS policy. Patient feedback on the Leg Club model is positive and the Leg Clubs provide a service to members which is well accepted by patients, yet is more economically efficient than the traditional district nursing practice of home visits. Lindsay Leg Clubs provide a valuable support service to the NHS in delivering improved quality of care while improving efficiency.

The Effect of a Mechanical Arm System on Portable Grinder Vibration Emissions

PubMed Central

McDowell, Thomas W.; Welcome, Daniel E.; Warren, Christopher; Xu, Xueyan S.; Dong, Ren G.

2016-01-01

Mechanical arm systems are commonly used to support powered hand tools to alleviate ergonomic stressors related to the development of workplace musculoskeletal disorders. However, the use of these systems can increase exposure times to other potentially harmful agents such as hand-transmitted vibration. To examine how these tool support systems affect tool vibration, the primary objectives of this study were to characterize the vibration emissions of typical portable pneumatic grinders used for surface grinding with and without a mechanical arm support system at a workplace and to estimate the potential risk of the increased vibration exposure time afforded by the use of these mechanical arm systems. This study also developed a laboratory-based simulated grinding task based on the ISO 28927-1 (2009) standard for assessing grinder vibrations; the simulated grinding vibrations were compared with those measured during actual workplace grinder operations. The results of this study demonstrate that use of the mechanical arm may provide a health benefit by reducing the forces required to lift and maneuver the tools and by decreasing hand-transmitted vibration exposure. However, the arm does not substantially change the basic characteristics of grinder vibration spectra. The mechanical arm reduced the average frequency-weighted acceleration by about 24% in the workplace and by about 7% in the laboratory. Because use of the mechanical arm system can increase daily time-on-task by 50% or more, the use of such systems may actually increase daily time-weighted hand-transmitted vibration exposures in some cases. The laboratory acceleration measurements were substantially lower than the workplace measurements, and the laboratory tool rankings based on acceleration were considerably different than those from the workplace. Thus, it is doubtful that ISO 28927-1 is useful for estimating workplace grinder vibration exposures or for predicting workplace grinder acceleration rank

Motor recovery of stroke patients after rehabilitation: one-year follow-up study.

PubMed

Kuptniratsaikul, Vilai; Kovindha, Apichana; Suethanapornkul, Sumalee; Massakulpan, Pornpimon; Permsirivanich, Wutichai; Kuptniratsaikul, Patcharawimol Srisa-An

2017-01-01

Purpose To investigate motor recovery of stroke patients 1 year after rehabilitation. Materials and Methods A cross-sectional study of 192 stroke patients discharged from rehabilitation wards in nine tertiary hospitals was conducted. Motor recovery was assessed using the Brunnstrom motor recovery stages (BMRS), at 6 and 12 months after discharge. Factors related to the BMRS of the hand, arm and leg were analyzed. Results The mean age of patients was 62.2 years (57.3% male). Significantly more patients presented improvement of at least one BMRS of the hand, arm and leg compared with those with decreasing BMRS (p < 0.001). The percentage of patients with BMRS III- VI at 6 months was greater than that at discharge, but the recovery at 12 months was slightly higher than that at 6 months. It seems that motor recovery from stroke was near maximal at six months. Regarding the factors related to motor recovery, only lengths of stay (LOS) <30 d during the first admission and Barthel index at discharge ≥10 were related to the improvement of BMRS of the hand, arm and leg on multivariate analysis. Additionally, no complication at discharge was associated with the improvement of BMRS of the leg. Conclusions Approximately half of our stroke patients had motor improvement of at least one stage of BMRS at one year. Motor recovery after stroke at the end of the first year was associated with shorter LOS during the first admission, higher discharge Barthel index score and absence of complications at discharge.

[Experience in using xeomin in the treatment of arm and hand spasticity in the early rehabilitation phase of stroke].

PubMed

Kostenko, E V; Petrova, L V; Ganzhula, P A; Lisenker, L N; Otcheskaia, O V; Khozova, A A; Boĭko, A N

2012-01-01

To reduce arm and hand spasticity, 28 patients in the early rehabilitation phase of ischemic hemisphere stroke received injections of the botulinum toxin A preparation xeomin in the content of complex rehabilitation programs. The following muscles: m. biceps brachii, m. flexor digitorum profundus, m. flexor digitorum superficialis, m. flexor carpi ulnaris, m. flexor carpi radialis were injected according to standard scheme. The total dose of drug was 200U in moderate (2-3 scores on the Ashworth scale) and 300U in marked (3-4 scores on the Ashworth scale) spasticity. Efficacy and safety of treatment was assessed at baseline and 2, 4, 8, 12, 16 weeks after injections. Xeomin significantly (p<0.05) reduced muscle tonus in patients with post-stroke spasticity of different severity. Clinical effect was seen 2 weeks after injection, it reached maximum at week 4 and then slowly decreased to week 16. The improved functional activity of the paretic arm (due to patient's and caregiver's reports) remained for to 12 weeks. The treatment was most effective in the group of patients with moderate spasticity. The correlation analysis confirmed that the severity of spasticity increased with the disease duration that reduced rehabilitation efficiency. The treatment with xeomin was safe, no serious side-effects were found.

Effects of age, sex and arm on the precision of arm position sense—left-arm superiority in healthy right-handers

PubMed Central

Schmidt, Lena; Depper, Lena; Kerkhoff, Georg

2013-01-01

Position sense is an important proprioceptive ability. Disorders of arm position sense (APS) often occur after unilateral stroke, and are associated with a negative functional outcome. In the present study we assessed horizontal APS by measuring angular deviations from a visually defined target separately for each arm in a large group of healthy subjects. We analyzed the accuracy and instability of horizontal APS as a function of age, sex and arm. Subjects were required to specify verbally the position of their unseen arm on a 0-90° circuit by comparing the current position with the target position indicated by a LED lamp, while the arm was passively moved by the examiner. Eighty-seven healthy subjects participated in the study, ranging from 20 to 77 years, subdivided into three age groups. The results revealed that APS was not a function of age or sex, but was significantly better in the non-dominant (left) arm in absolute errors (AE) but not in constant errors (CE) across all age groups of right-handed healthy subjects. This indicates a right-hemisphere superiority for left APS in right-handers and neatly fits to the more frequent and more severe left-sided body-related deficits in patients with unilateral stroke (i.e. impaired APS in left spatial neglect, somatoparaphrenia) or in individuals with abnormalities of the right cerebral hemisphere. These clinical issues will be discussed. PMID:24399962

Optimal Body Size and Limb Length Ratios Associated with 100-m Personal-Best Swim Speeds.

PubMed

Nevill, Alan M; Oxford, Samuel W; Duncan, Michael J

2015-08-01

This study aims to identify optimal body size and limb segment length ratios associated with 100-m personal-best (PB) swim speeds in children and adolescents. Fifty national-standard youth swimmers (21 males and 29 females age 11-16 yr; mean ± SD age, 13.5 ± 1.5 yr) participated in the study. Anthropometry comprised stature; body mass; skinfolds; maturity offset; upper arm, lower arm, and hand lengths; and upper leg, lower leg, and foot lengths. Swimming performance was taken as the PB time recorded in competition for the 100-m freestyle swim. To identify the optimal body size and body composition components associated with 100-m PB swim speeds (having controlled for age and maturity offset), we adopted a multiplicative allometric log-linear regression model, which was refined using backward elimination. Lean body mass was the singularly most important whole-body characteristic. Stature and body mass did not contribute to the model, suggesting that the advantage of longer levers was limb-specific rather than a general whole-body advantage. The allometric model also identified that having greater limb segment length ratios [i.e., arm ratio = (low arm)/(upper arm); foot-to-leg ratio = (foot)/(lower leg)] was key to PB swim speeds. It is only by adopting multiplicative allometric models that the above mentioned ratios could have been derived. The advantage of having a greater lower arm is clear; however, having a shorter upper arm (achieved by adopting a closer elbow angle technique or by possessing a naturally endowed shorter upper arm), at the same time, is a new insight into swimming performance. A greater foot-to-lower-leg ratio suggests that a combination of larger feet and shorter lower leg length may also benefit PB swim speeds.

Stopping Speech Suppresses the Task-Irrelevant Hand

ERIC Educational Resources Information Center

Cai, Weidong; Oldenkamp, Caitlin L.; Aron, Adam R.

2012-01-01

Some situations require one to quickly stop an initiated response. Recent evidence suggests that rapid stopping engages a mechanism that has diffuse effects on the motor system. For example, stopping the hand dampens the excitability of the task-irrelevant leg. However, it is unclear whether this "global suppression" could apply across wider motor…

Explaining Away the Body: Experiences of Supernaturally Caused Touch and Touch on Non-Hand Objects within the Rubber Hand Illusion

PubMed Central

2010-01-01

Background In rubber hand illusions and full body illusions, touch sensations are projected to non-body objects such as rubber hands, dolls or virtual bodies. The robustness, limits and further perceptual consequences of such illusions are not yet fully explored or understood. A number of experiments are reported that test the limits of a variant of the rubber hand illusion. Methodology/Principal Findings A variant of the rubber hand illusion is explored, in which the real and foreign hands are aligned in personal space. The presence of the illusion is ascertained with participants' scores and temperature changes of the real arm. This generates a basic illusion of touch projected to a foreign arm. Participants are presented with further, unusual visuotactile stimuli subsequent to onset of the basic illusion. Such further visuotactile stimulation is found to generate very unusual experiences of supernatural touch and touch on a non-hand object. The finding of touch on a non-hand object conflicts with prior findings, and to resolve this conflict a further hypothesis is successfully tested: that without prior onset of the basic illusion this unusual experience does not occur. Conclusions/Significance A rubber hand illusion is found that can arise when the real and the foreign arm are aligned in personal space. This illusion persists through periods of no tactile stimulation and is strong enough to allow very unusual experiences of touch felt on a cardboard box and experiences of touch produced at a distance, as if by supernatural causation. These findings suggest that one's visual body image is explained away during experience of the illusion and they may be of further importance to understanding the role of experience in delusion formation. The findings of touch on non-hand objects may help reconcile conflicting results in this area of research. In addition, new evidence is provided that relates to the recently discovered psychologically induced temperature changes

Evaluation of hand-arm and whole-body vibrations in construction and property management.

PubMed

Coggins, Marie A; Van Lente, Eric; McCallig, Margaret; Paddan, Gurmail; Moore, Ken

2010-11-01

To identify and measure the magnitude of hand-arm vibration (HAV) and whole-body vibration (WBV) sources (tools, vehicles etc.) in use within a previously unexamined sector: a construction and property management company. To evaluate the effect of factors such as age of tool, materials being worked on, number and location of tool handles, tool weight, and manufacturer brand on HAV magnitude and the effect of factors such as manufacturer machine brand, terrain, and work task on WBV magnitude. This study was carried out in a construction and property management company, employees (n = 469) working in the engineering services and maintenance departments who use vibrating equipment as part of their work were invited to participate. Two hundred and eighty-nine employees working as general operatives, excavator drivers, stone masons, carpenters, labourers, fitters, welders, and gardeners agreed to participate. A total of 20 types of hand tool (n = 264) and 11 types of vehicle (n = 158) in use within the company were selected for inclusion in the study. Five pieces of equipment had never previously been measured. Vibration measurements were carried out in accordance with ISO 5349-1 (Mechanical vibration-measurement and assessment of human exposure to hand transmitted vibration-Part 1: general guidance. 2001) (HAV) and ISO 2631-1 (Mechanical vibration and shock: evaluation of human exposure to WBV in the working environment. Part 1-general requirements. 1997) (WBV). Vibration measurements were made while workers were operating the equipment as part of their normal work activities. A wide range of vibration emission values were recorded for most tool types, e.g. orbital sanders (1.39-10.90 m s⁻²) and angle grinders (0.28-12.25 m s⁻²), and vehicle, e.g. forklifts (0.41-1.00 m s⁻²) and tractors (0.04-0.42 m s⁻²). Vibration magnitudes were largely consistent with those found in previous studies. The highest HAV magnitude was measured on a demolition hammer (13.3 m

Diagnosis and treatment of hand-arm vibration syndrome and its relationship to carpal tunnel syndrome.

PubMed

Falkiner, Sonja

2003-07-01

Hand-arm vibration syndrome (HAVS) is a condition associated with the use of vibrating tools that occurs mainly in men. It consists primarily of 'occupational' Raynaud disease and digital polyneuropathy. Carpal tunnel syndrome (CTS) is also associated with hand transmitted vibration exposure and can coexist with HAVS. This article examines recent papers on causation, diagnosis, relationship to CTS and treatment. A Medline search was conducted, as was a search of UK, USA and Australian government occupational health and safety websites. Published papers that were single case studies or of poor design were not included. There are no 'gold standard' diagnostic tests for HAVS. It can mimic CTS in temperate climates and can occur with CTS. This is the diagnostic challenge when a male worker presents with apparent CTS symptoms. If he has worked with vibrating tools for many years, a diagnosis of HAVS or co-diagnosis of HAVS should be considered before a diagnosis of pure CTS is made. Nonwork risk factors for HAVS are predisposition, smoking, and exposure to vibration outside work. Cessation of exposure (and smoking) and redeployment is a critical part of treatment due to the dose response relationship of HAVS. This contrasts with adequately treated CTS, where the vast majority of workers can return to pre-injury duties. In severe cases, calcium antagonists are also used, but treatment is often ineffective. Few workplaces in Australia manage vibration risk or conduct screening to identify workers with early HAVS who should be redeployed. Local doctors have an important opportunity to diagnose HAVS and to make recommendations to the workplace on redeployment as part of treatment before symptoms become irreversible.

Contralesional arm preference depends on hemisphere of damage and target location in unilateral stroke patients

PubMed Central

Mani, Saandeep; Przybyla, Andrzej; Good, David C.; Haaland, Kathleen Y.; Sainburg, Robert L.

2014-01-01

Background Previous research has shown that during simulated activities of daily living right handed stroke patients use their contralesional arm more after left than right hemisphere stroke. These findings were attributed to a hand preference effect. However, these decisions about when to use the contralesional arm may be modulated by where in the work space the task is performed, a factor that could be used in physical rehabilitation to influence recovery by decreasing learned non-use. Objective To examine how target location and side of stroke influences arm selection choices for simple reaching movements. Methods Fourteen right-handed stroke patients (7 with left hemisphere damage, 7 with right hemisphere damage) with similar degree of hemiparesis (Fugl-Meyer motor score), and 16 right-handed control subjects participated in this experiment. Thirty-two targets were presented throughout the reachable horizontal plane workspace in a pseudo-random fashion, and the subjects were asked to select one hand to reach the target on each trial. Results The left hemisphere damaged group chose their contralesional arm significantly more often than the right hemisphere damaged group. Patients with right hemisphere damage also chose their left (contralesional) arm significantly less than the control group. However, these patterns of choice were most pronounced in the center of the workspace. Conclusion Both the side of hemisphere damage and workspace location played a significant role in the choice of whether to use the contralesional arm for reaching. These findings have implications for structuring rehabilitation for unilateral stroke patients. PMID:24523143

Color Camera for Curiosity Robotic Arm

NASA Image and Video Library

2010-11-16

The Mars Hand Lens Imager MAHLI camera will fly on NASA Mars Science Laboratory mission, launching in late 2011. This photo of the camera was taken before MAHLI November 2010 installation onto the robotic arm of the mission Mars rover, Curiosity.

Targeted Muscle Reinnervation for Real-Time Myoelectric Control of Multifunction Artificial Arms

PubMed Central

Kuiken, Todd A.; Li, Guanglin; Lock, Blair A.; Lipschutz, Robert D.; Miller, Laura A.; Stubblefield, Kathy A.; Englehart, Kevin

2011-01-01

Context Improving the function of prosthetic arms remains a challenge, as access to the neural control information for the arm is lost during amputation. We have developed a surgical technique called targeted muscle reinnervation (TMR) which transfers residual arm nerves to alternative muscle sites. After reinnervation, these target muscles produce an electromyogram (EMG) on the surface of the skin that can be measured and used to control prosthetic arms. Objective Assess the performance of TMR upper-limb amputee patients using a pattern-recognition algorithm to decode EMG signals and control prosthetic arm motions. Design Surface EMG signals were recorded on participants and decoded using a pattern-recognition algorithm. The decoding program controlled the movement of a virtual prosthetic arm. Participants were instructed to perform various arm movements, and their abilities to control the virtual prosthetic arm were measured. In addition, TMR patients used the same control system to operate advanced arm prosthesis prototypes. Setting This study was conducted between January 2007 and January 2008 at the Rehabilitation Institute of Chicago. Participants This study included five patients with shoulder disarticulation or transhumeral amputations who received TMR surgery between February 2002 and October 2006. It also included five non-amputee (control) participants. Main Outcome Measure Performance metrics measured during virtual arm movements included motion-selection time, motion-completion time, and motion-completion (or `success') rate. Three of the TMR patients were also able to test advanced arm prostheses. Results TMR patients were able to repeatedly perform 10 different elbow, wrist and hand motions with the virtual prosthetic arm. For TMR patients, the average (standard deviation (SD)) motion-selection and motion-completion times for elbow and wrist movements were 0.22 s (0.06) and 1.29 s (0.15), respectively. These times were 0.06 s and 0.21 s longer than

Leg blood pressure measured in orthostatic posture is associated with left ventricular mass in normotensive subjects.

PubMed

Gemignani, Tiago; Matos-Souza, José R; Franchini, Kleber G; Nadruz, Wilson

2012-10-01

Changing from a supine to an orthostatic posture is associated with substantial increments in leg blood pressure (BP) levels, which could ultimately influence the hemodynamic burden imposed on the heart. This study investigated the relationship between brachial and leg BP measurements and the left cardiac chamber's structure and assessed the role of body posture changes in this regard. One hundred and thirty normotensive, nondiabetic, nonsmoking, normolipemic subjects were evaluated by a clinical history, anthropometry, the analysis of metabolic parameters, echocardiography, and the measurement of BP in the arm and the calf in both supine and orthostatic positions. Significant correlation coefficients between the leg BP measurements and the cardiac structure were detected, especially between the orthostatic pulse pressure (PP) and the left ventricular (LV) wall thickness (r = 0.38; P < 0.001), the orthostatic PP and the LV mass (r = 0.37; P < 0.001), and the orthostatic systolic BP (SBP) and the left atrial size (r = 0.35; P < 0.001). Stepwise and standard regression analysis adjusted for brachial BP and anthropometric and metabolic variables confirmed that the leg orthostatic PP was independently related to the LV wall thickness and mass. Moreover, the leg orthostatic SBP was associated with the left atrial dimension even after adding the LV mass to the statistical models. Finally, triglyceride levels and body surface area showed significant relationship with leg orthostatic PP and SBP, whereas brachial orthostatic PP and SBP were only associated with age and anthropometric variables. Orthostatic leg BP is independently associated with the cardiac structure in normotensive subjects.

Uptake and quality of health surveillance for noise and hand-arm vibration.

PubMed

Poole, K; Mason, H J; Harris-Roberts, J

2011-08-01

Health surveillance (HS) is required for employees if noise or hand-arm vibration (HAV) exposures are likely to be above exposure action levels. The extent to which employers comply with Health and Safety Executive (HSE) regulations is unclear. To establish the uptake and quality of HS for noise and HAV in high-risk industries. A cross-sectional telephone-based questionnaire study involving employers in high-risk industries for noise or HAV. A total of 246 and 386 interviews were completed for noise and HAV, respectively. The uptake of HS in the cohorts was 17 and 10%, respectively. Selection of those companies thought to have 'higher risk' increased the uptake to 25 and 18%, respectively. The proportion of companies carrying out HS was strongly related to the size of the company, with smaller companies less likely to provide this for their employees. A large proportion of companies that reported having HS in place had formal procedures for managing exposed workers (90 and 83% for noise and HAV, respectively), received feedback on individual workers (81 and 80%) and some reported that they used this information to inform their risk management process (58 and 63%). The frequency of HS for HAV was in line with that suggested in HSE guidance in 70% of cases, however, for noise, it was often utilized more frequently. While many of the companies appear to be following HSE guidance, there is a significant number that are not. Further initiatives that engage with smaller companies may help increase HS provision.

A Subcortical Oscillatory Network Contributes to Recovery of Hand Dexterity after Spinal Cord Injury

ERIC Educational Resources Information Center

Nishimura, Yukio; Morichika, Yosuke; Isa, Tadashi

2009-01-01

Recent studies have shown that after partial spinal-cord lesion at the mid-cervical segment, the remaining pathways compensate for restoring finger dexterity; however, how they control hand/arm muscles has remained unclear. To elucidate the changes in dynamic properties of neural circuits connecting the motor cortex and hand/arm muscles, we…

A pilot study of gene expression analysis in workers with hand-arm vibration syndrome.

PubMed

Maeda, Setsuo; Yu, Xiaozhong; Wang, Rui-Sheng; Sakakibara, Hisataka

2008-04-01

The purpose of this pilot study was to examine differences in gene expressions by cDNA microarray analysis of hand-arm vibration syndrome (HAVS) patients. Vein blood samples were collected and total RNA was extracted. All blood samples were obtained in the morning in one visit after a standard light breakfast. We performed microarray analysis with the labeled cDNA prepared by reverse transcription from RNA samples, using the Human CHIP version 1 (DNA Chip Research Inc, Yokohama, Japan). There are 2,976 genes on the chip, and these genes were selected from a cDNA library prepared with human peripheral white blood cells (WBC). Different gene levels between the HAVS patients and controls, and between groups of HAVS with different levels of symptoms, were indicated by the randomized variance model. The most up-regulated genes were analyzed for their possible functions and association with the occurrence of HAVS. From the results of this pilot study, although the results were obtained a limited number of subjects, it would appear that cDNA microarray analysis of HAVS patients has potential as a new objective method of HAVS diagnosis. Further research is needed to examine the gene expression with increased numbers of patients at different stages of HAVS.

Impact of body posture on laterality judgement and explicit recognition tasks performed on self and others' hands.

PubMed

Conson, Massimiliano; Errico, Domenico; Mazzarella, Elisabetta; De Bellis, Francesco; Grossi, Dario; Trojano, Luigi

2015-04-01

Judgments on laterality of hand stimuli are faster and more accurate when dealing with one's own than others' hand, i.e. the self-advantage. This advantage seems to be related to activation of a sensorimotor mechanism while implicitly processing one's own hands, but not during explicit one's own hand recognition. Here, we specifically tested the influence of proprioceptive information on the self-hand advantage by manipulating participants' body posture during self and others' hand processing. In Experiment 1, right-handed healthy participants judged laterality of either self or others' hands, whereas in Experiment 2, an explicit recognition of one's own hands was required. In both experiments, the participants performed the task while holding their left or right arm flexed with their hand in direct contact with their chest ("flexed self-touch posture") or with their hand placed on a wooden smooth surface in correspondence with their chest ("flexed proprioceptive-only posture"). In an "extended control posture", both arms were extended and in contact with thighs. In Experiment 1 (hand laterality judgment), we confirmed the self-advantage and demonstrated that it was enhanced when the subjects judged left-hand stimuli at 270° orientation while keeping their left arm in the flexed proprioceptive-only posture. In Experiment 2 (explicit self-hand recognition), instead, we found an advantage for others' hand ("self-disadvantage") independently from posture manipulation. Thus, position-related proprioceptive information from left non-dominant arm can enhance sensorimotor one's own body representation selectively favouring implicit self-hands processing.

Learning and Control Model of the Arm for Loading

NASA Astrophysics Data System (ADS)

Kim, Kyoungsik; Kambara, Hiroyuki; Shin, Duk; Koike, Yasuharu

We propose a learning and control model of the arm for a loading task in which an object is loaded onto one hand with the other hand, in the sagittal plane. Postural control during object interactions provides important points to motor control theories in terms of how humans handle dynamics changes and use the information of prediction and sensory feedback. For the learning and control model, we coupled a feedback-error-learning scheme with an Actor-Critic method used as a feedback controller. To overcome sensory delays, a feedforward dynamics model (FDM) was used in the sensory feedback path. We tested the proposed model in simulation using a two-joint arm with six muscles, each with time delays in muscle force generation. By applying the proposed model to the loading task, we showed that motor commands started increasing, before an object was loaded on, to stabilize arm posture. We also found that the FDM contributes to the stabilization by predicting how the hand changes based on contexts of the object and efferent signals. For comparison with other computational models, we present the simulation results of a minimum-variance model.

The Relationship among Leg Strength, Leg Power and Alpine Skiing Success.

ERIC Educational Resources Information Center

Gettman, Larry R.; Huckel, Jack R.

The purpose of this study was to relate leg strength and power to alpine skiing success as measured by FIS points. Isometric leg strength was represented by the knee extension test described by Clarke. Leg power was measured by the vertical jump test and the Margaria-Kalamen stair run. Results in the strength and power tests were correlated with…

Corticotropin, Repository Injection

MedlinePlus

Corticotropin repository injection is used to treat the following conditions:infantile spasms (seizures that usually begin during the first ... of the arms, hands, feet, and legs). Corticotropin repository injection is in a class of medications called ...

Reduced oxygen cost of running is related to alignment of the resultant GRF and leg axis vector: A pilot study.

PubMed

Moore, I S; Jones, A M; Dixon, S J

2016-07-01

This pilot study investigated whether a 10-week running program (10wkRP), which reduced the oxygen cost of running, affected resultant ground reaction force (GRF), leg axis alignment, joint moment characteristics, and gear ratios. Ten novice, female runners completed a 10wkRP. Running kinematics and kinetics, in addition to oxygen consumption ( V ˙ O 2 ) during steady-state running, were recorded pre- and post-10wkRP. V ˙ O 2 decreased (8%) from pre-10wkRP to post-10wkRP. There was a better alignment of the resultant GRF and leg axis at peak propulsion post-10wkRP compared with pre-10wkRP (10.8 ± 4.9 vs 1.6 ± 1.2°), as the resultant GRF vector was applied 7 ± 0.6° (P = 0.008) more horizontally. There were shorter external ankle moment arms (24%) and smaller knee extensor moments (23%) at peak braking post-10wkRP. The change in V ˙ O 2 was associated with the change in alignment of the resultant GRF and leg axis (rs  = 0.88, P = 0.003). As runners became more economical, they exhibited a more aligned resultant GRF vector and leg axis at peak propulsion. This appears to be a self-optimization strategy that may improve performance. Additionally, changes to external ankle moment arms indicated beneficial low gear ratios were achieved at the time of peak braking force. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Multiple sensor smart robot hand with force control

NASA Technical Reports Server (NTRS)

Killion, Richard R.; Robinson, Lee R.; Bejczy, Antal

1987-01-01

A smart robot hand developed at JPL for the Protoflight Manipulator Arm (PFMA) is described. The development of this smart hand was based on an integrated design and subsystem architecture by considering mechanism, electronics, sensing, control, display, and operator interface in an integrated design approach. The mechanical details of this smart hand and the overall subsystem are described elsewhere. The sensing and electronics components of the JPL/PFMA smart hand are summarized and it is described in some detail in control capabilities.

Hand-Eye Calibration of Robonaut

NASA Technical Reports Server (NTRS)

Nickels, Kevin; Huber, Eric

2004-01-01

NASA's Human Space Flight program depends heavily on Extra-Vehicular Activities (EVA's) performed by human astronauts. EVA is a high risk environment that requires extensive training and ground support. In collaboration with the Defense Advanced Research Projects Agency (DARPA), NASA is conducting a ground development project to produce a robotic astronaut's assistant, called Robonaut, that could help reduce human EVA time and workload. The project described in this paper designed and implemented a hand-eye calibration scheme for Robonaut, Unit A. The intent of this calibration scheme is to improve hand-eye coordination of the robot. The basic approach is to use kinematic and stereo vision measurements, namely the joint angles self-reported by the right arm and 3-D positions of a calibration fixture as measured by vision, to estimate the transformation from Robonaut's base coordinate system to its hand coordinate system and to its vision coordinate system. Two methods of gathering data sets have been developed, along with software to support each. In the first, the system observes the robotic arm and neck angles as the robot is operated under external control, and measures the 3-D position of a calibration fixture using Robonaut's stereo cameras, and logs these data. In the second, the system drives the arm and neck through a set of pre-recorded configurations, and data are again logged. Two variants of the calibration scheme have been developed. The full calibration scheme is a batch procedure that estimates all relevant kinematic parameters of the arm and neck of the robot The daily calibration scheme estimates only joint offsets for each rotational joint on the arm and neck, which are assumed to change from day to day. The schemes have been designed to be automatic and easy to use so that the robot can be fully recalibrated when needed such as after repair, upgrade, etc, and can be partially recalibrated after each power cycle. The scheme has been implemented on

Single-leg squats can predict leg alignment in dancers performing ballet movements in "turnout".

PubMed

Hopper, Luke S; Sato, Nahoko; Weidemann, Andries L

2016-01-01

The physical assessments used in dance injury surveillance programs are often adapted from the sports and exercise domain. Bespoke physical assessments may be required for dance, particularly when ballet movements involve "turning out" or external rotation of the legs beyond that typically used in sports. This study evaluated the ability of the traditional single-leg squat to predict the leg alignment of dancers performing ballet movements with turnout. Three-dimensional kinematic data of dancers performing the single-leg squat and five ballet movements were recorded and analyzed. Reduction of the three-dimensional data into a one-dimensional variable incorporating the ankle, knee, and hip joint center positions provided the strongest predictive model between the single-leg squat and the ballet movements. The single-leg squat can predict leg alignment in dancers performing ballet movements, even in "turned out" postures. Clinicians should pay careful attention to observational positioning and rating criteria when assessing dancers performing the single-leg squat.

Hand grip strength and anthropometric characteristics in Italian female national basketball teams.

PubMed

Pizzigalli, Luisa; Micheletti Cremasco, Margherita; LA Torre, Antonio; Rainoldi, Alberto; Benis, Roberto

2017-05-01

The aim of this study was to investigate the influence of hand and body dimensions on hand grip strength and to define a reference scale for talent identification in basketball players. Body and hand anthropometric data and the maximal handgrip strength of 109 female Italian basketball National players (Under14-Seniores) were measured. Handgrip strength and arm length trend increased, raising the statistical significant differences only for players from the age of 19 (U20, Seniores) with respect to sub-elite groups (U14, U15) (P<0.05). Handgrip strength showed low positive correlations with height and Body Mass Index but a positive relationships with arm length (r=0.5; P<0.001). Findings underline training and years of practice have effects on increasing handgrip strength. Data show that to select female basketball players by arm length means selecting by handgrip strength. Thus it is possible to suggest that in addition to height, arm length could also be considered a useful parameter in young female talent identification.

The Effect of a Mechanical Arm System on Portable Grinder Vibration Emissions.

PubMed

McDowell, Thomas W; Welcome, Daniel E; Warren, Christopher; Xu, Xueyan S; Dong, Ren G

2016-04-01

Mechanical arm systems are commonly used to support powered hand tools to alleviate ergonomic stressors related to the development of workplace musculoskeletal disorders. However, the use of these systems can increase exposure times to other potentially harmful agents such as hand-transmitted vibration. To examine how these tool support systems affect tool vibration, the primary objectives of this study were to characterize the vibration emissions of typical portable pneumatic grinders used for surface grinding with and without a mechanical arm support system at a workplace and to estimate the potential risk of the increased vibration exposure time afforded by the use of these mechanical arm systems. This study also developed a laboratory-based simulated grinding task based on the ISO 28927-1 (2009) standard for assessing grinder vibrations; the simulated grinding vibrations were compared with those measured during actual workplace grinder operations. The results of this study demonstrate that use of the mechanical arm may provide a health benefit by reducing the forces required to lift and maneuver the tools and by decreasing hand-transmitted vibration exposure. However, the arm does not substantially change the basic characteristics of grinder vibration spectra. The mechanical arm reduced the average frequency-weighted acceleration by about 24% in the workplace and by about 7% in the laboratory. Because use of the mechanical arm system can increase daily time-on-task by 50% or more, the use of such systems may actually increase daily time-weighted hand-transmitted vibration exposures in some cases. The laboratory acceleration measurements were substantially lower than the workplace measurements, and the laboratory tool rankings based on acceleration were considerably different than those from the workplace. Thus, it is doubtful that ISO 28927-1 is useful for estimating workplace grinder vibration exposures or for predicting workplace grinder acceleration rank

Dynamically Stable Legged Locomotion.

DTIC Science & Technology

1983-01-27

sweeps the leg during stance, and the third places the foot during flight and controls body attitude during stance. Each of the three methods elucidates...secondary strategy has been to examine systems with springy legs, so that the role of resonant oscillatory leg behavior might be better understood. ’ The ...body attitude : I lopping _leit: ’ The control system rcgulate:; hopping height by manlil)Lulating hopping energy. The leg is springy, so hopping is a

Metastatic Crohn disease clinically reminiscent of erythema nodosum on the right leg.

PubMed

Park, Hyun C; Kim, Hyun W; Park, Chan G; Ko, Joo Y

2016-09-01

Cutaneous manifestations are well-recognized complications of Crohn disease (CD) that can be divided into disease-specific and reactive conditions. One of the most common reactive conditions is erythema nodosum (EN), which presents as subcutaneous tender nodules most often on the legs. On the other hand, metastatic Crohn disease (MCD) is a rare cutaneous manifestation of CD defined as the presence of noncaseating granulomas that are not contiguous with the gastrointestinal (GI) tract. The clinical presentation of MCD is variable; however, lesions often are located on the legs and genital region. We report the case of a 21-year-old woman with a 6-year history of CD who presented with MCD clinically simulating EN.

Development of a set of activities to evaluate the arm and hand function in children with obstetric brachial plexus lesion.

PubMed

Boeschoten, K H; Folmer, K B; van der Lee, J H; Nollet, F

2007-02-01

To develop an observational instrument that can be used to evaluate the quality of arm and hand skills in daily functional activities in children with obstetric brachial plexus lesion (OBPL). A set of functional activities was constructed and standardized, and the intra-observer reliability of the assessment of this set of activities was studied. Department of Occupational Therapy and Department of Rehabilitation Medicine, VU University Medical Centre. Twenty-six children with OBPL in the age range of 4 -6 years. The children were asked to perform 47 bimanual activities, which were recorded on videotape. The videotapes were scored twice by the same occupational therapist. The percentage of agreement in scoring 'hand-use', 'speed' and 'assistance' was over 80% for a substantial number of activities, indicating a strong agreement. However, in scoring 'deviations in movements and body posture' the percentage of agreement was insufficient in most activities. This set of activities has good potential for assessment of the performance of functional activities in children with OBPL. This study, however, showed a number of difficulties in observing and scoring the activities that have to be considered when developing a standardized video observation.

Effects of wrist tendon vibration on targeted upper-arm movements in poststroke hemiparesis.

PubMed

Conrad, Megan O; Scheidt, Robert A; Schmit, Brian D

2011-01-01

Impaired motor control of the upper extremity after stroke may be related to lost sensory, motor, and integrative functions of the brain. Artificial activation of sensory afferents might improve control of movement by adding excitatory drive to sensorimotor control structures. The authors evaluated the effect of wrist tendon vibration (TV) on paretic upper-arm stability during point-to-point planar movements. TV (70 Hz) was applied to the forearm wrist musculature of 10 hemiparetic stroke patients as they made center-out planar arm movements. End-point stability, muscle activity, and grip pressure were compared as patients stabilized at the target position for trials completed before, during, and after the application of the vibratory stimulus. Prior to vibration, hand position fluctuated as participants attempted to maintain the hand at the target after movement termination. TV improved arm stability, as evidenced by decreased magnitude of hand tangential velocity at the target. Improved stability was accompanied by a decrease in muscle activity throughout the arm as well as a mean decrease in grip pressure. These results suggest that vibratory stimulation of the distal wrist musculature enhances stability of the proximal arm and can be studied further as a mode for improving end-point stability during reaching in hemiparetic patients.

A cross sectional study on hand-arm vibration syndrome among a group of tree fellers in a tropical environment.

PubMed

Su, Anselm Ting; Maeda, Setsuo; Fukumoto, Jin; Miyai, Nobuyuki; Isahak, Marzuki; Yoshioka, Atsushi; Nakajima, Ryuichi; Bulgiba, Awang; Miyashita, Kazuhisa

2014-01-01

This study aimed to explore the clinical characteristics of hand arm vibration syndrome (HAVS) in a group of tree fellers in a tropical environment. We examined all tree fellers and selected control subjects in a logging camp of central Sarawak for vibration exposure and presence of HAVS symptoms utilizing vibrotactile perception threshold test (VPT) and cold water provocation test (CWP). None of the subjects reported white finger. The tree fellers reported significantly higher prevalence of finger coldness as compared to the control subjects (OR=10.32, 95%CI=1.21-87.94). A lower finger skin temperature, longer fingernail capillary return time and higher VPT were observed among the tree fellers as compared to the control subjects in all fingers (effect size >0.5). The VPT following CWP of the tree fellers was significantly higher (repeated measures ANOVA p=0.002, partial η(2)=0.196) than the control subject. The A (8) level was associated with finger tingling, numbness and dullness (effect size=0.983) and finger coldness (effect size=0.524) among the tree fellers. Finger coldness and finger tingling, numbness and dullness are important symptoms for HAVS in tropical environment that may indicate vascular and neurological damage due to hand-transmitted vibration exposure.

Split-belt walking adaptation recalibrates sensorimotor estimates of leg speed but not position or force

PubMed Central

Vazquez, Alejandro; Statton, Matthew A.; Busgang, Stefanie A.

2015-01-01

Motor learning during reaching not only recalibrates movement but can also lead to small but consistent changes in the sense of arm position. Studies have suggested that this sensory effect may be the result of recalibration of a forward model that associates motor commands with their sensory consequences. Here we investigated whether similar perceptual changes occur in the lower limbs after learning a new walking pattern on a split-belt treadmill—a task that critically involves proprioception. Specifically, we studied how this motor learning task affects perception of leg speed during walking, perception of leg position during standing or walking, and perception of contact force during stepping. Our results show that split-belt adaptation leads to robust motor aftereffects and alters the perception of leg speed during walking. This is specific to the direction of walking that was trained during adaptation (i.e., backward or forward). The change in leg speed perception accounts for roughly half of the observed motor aftereffect. In contrast, split-belt adaptation does not alter the perception of leg position during standing or walking and does not change the perception of stepping force. Our results demonstrate that there is a recalibration of a sensory percept specific to the domain of the perturbation that was applied during walking (i.e., speed but not position or force). Furthermore, the motor and sensory consequences of locomotor adaptation may be linked, suggesting overlapping mechanisms driving changes in the motor and sensory domains. PMID:26424576

The relationship between clinical and standardized tests for hand-arm vibration syndrome.

PubMed

Poole, C J M; Mason, H; Harding, A-H

2016-06-01

Standardized laboratory tests are undertaken to assist the diagnosis and staging of hand-arm vibration syndrome (HAVS), but the strength of the relationship between the tests and clinical stages of HAVS is unknown. To assess the relationship between the results of thermal aesthesiometry (TA), vibrotactile (VT) thresholds and cold provocation (CP) tests with the modified Stockholm scales for HAVS and to determine whether the relationship is affected by finger skin temperature. Consecutive records of workers referred to a Tier 5 HAVS assessment centre from 2006 to 2015 were identified. The diagnosis and staging of cases was undertaken from the clinical information contained in the records. Cases with alternative or mixed diagnoses were excluded and staging performed according to the modified Stockholm scale without knowledge of the results of the standardized laboratory tests. A total of 279 cases of HAVS were analysed. Although there was a significant trend for sensorineural (SN) and vascular scores to increase with clinical stage (P < 0.01), there was no significant difference in scores between 2SN early and 2SN late or between 2SN late and 3SN. There was moderate correlation between the TA and VT scores and the clinical SN stages (r = 0.6). This correlation did not change when subjects were divided into those with a finger skin temperature <30 and >30°C. CP scores distributed bimodally and correlated poorly with clinical staging (r = 0.2). Standardized SN tests distinguish between the lower Stockholm stages, but not above 2SN early. This has implications for health surveillance and UK policy. © Crown copyright 2016.

VO2 Kinetics in All-out Arm Stroke, Leg Kick and Whole Stroke Front Crawl 100-m Swimming.

PubMed

Rodríguez, F A; Lätt, E; Jürimäe, J; Maestu, J; Purge, P; Rämson, R; Haljaste, K; Keskinen, K L; Jürimäe, T

2016-03-01

The VO2 response to extreme-intensity exercise and its relationship with sports performance are largely unexplored. This study investigated the pulmonary VO2 kinetics during all-out 100-m front crawl whole stroke swimming (S), arm stroke (A) and leg kick (L). 26 male and 10 female competitive swimmers performed an all-out S trial followed by A and L of equal duration in random order. Breath-by-breath VO2 was measured using a snorkel attached to a portable gas analyzer. Mean (±SD) primary component parameters and peak blood lactate (Lapeak) during S, A, and L were, respectively: time delay (s), 14.2 ± 4.7, 14.3 ± 4.5, 15.6 ± 5.1; amplitude (ml·kg(-1)·min(-1)), 46.8 ± 6.1, 37.3 ± 6.9, 41.0 ± 4.7; time constant (τ, s): 9.2 ± 3.2, 12.4 ± 4.7, 10.1 ± 3.2; Lapeak (mmol·l(-1)), 6.8 ± 3.1, 6.3 ± 2.5, 7.9 ± 2.8. During A and L respectively, 80% and 87% of amplitude in S was reached, whereas A+L were 68% greater than in S. 100-m performance was associated to shorter cardiodynamic phase and greater VO2 amplitude and Lapeak (accounting up to 61% of performance variance), but not to τ. We conclude that (i) VO2 gain was proportional to exercise intensity and muscle mass involved, (ii) kicking is metabolically less efficient, and (iii) the main limiting factor of peak VO2 appears to be O2 delivery and not muscle extraction. © Georg Thieme Verlag KG Stuttgart · New York.

Venous leg ulcers

PubMed Central

2011-01-01

Introduction Leg ulcers usually occur secondary to venous reflux or obstruction, but 20% of people with leg ulcers have arterial disease, with or without venous disorders. Between 1.5 and 3.0/1000 people have active leg ulcers. Prevalence increases with age to about 20/1000 in people aged over 80 years. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of standard treatments, adjuvant treatments, and organisational interventions for venous leg ulcers? What are the effects of advice about self-help interventions in people receiving usual care for venous leg ulcers? What are the effects of interventions to prevent recurrence of venous leg ulcers? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2011 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 101 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: compression bandages and stockings, cultured allogenic (single or bilayer) skin replacement, debriding agents, dressings (cellulose, collagen, film, foam, hyaluronic acid-derived, semi-occlusive alginate), hydrocolloid (occlusive) dressings in the presence of compression, intermittent pneumatic compression, intravenous prostaglandin E1, larval therapy, laser treatment (low-level), leg ulcer clinics, multilayer elastic system, multilayer elastomeric (or non-elastomeric) high-compression regimens or bandages, oral treatments (aspirin, flavonoids

Endoscopic endonasal transsphenoidal surgery using the iArmS operation support robot: initial experience in 43 patients.

PubMed

Ogiwara, Toshihiro; Goto, Tetsuya; Nagm, Alhusain; Hongo, Kazuhiro

2017-05-01

Objective The intelligent arm-support system, iArmS, which follows the surgeon's arm and automatically fixes it at an adequate position, was developed as an operation support robot. iArmS was designed to support the surgeon's forearm to prevent hand trembling and to alleviate fatigue during surgery with a microscope. In this study, the authors report on application of this robotic device to endoscopic endonasal transsphenoidal surgery (ETSS) and evaluate their initial experiences. Methods The study population consisted of 43 patients: 29 with pituitary adenoma, 3 with meningioma, 3 with Rathke's cleft cyst, 2 with craniopharyngioma, 2 with chordoma, and 4 with other conditions. All patients underwent surgery via the endonasal transsphenoidal approach using a rigid endoscope. During the nasal and sphenoid phases, iArmS was used to support the surgeon's nondominant arm, which held the endoscope. The details of the iArmS and clinical results were collected. Results iArmS followed the surgeon's arm movement automatically. It reduced the surgeon's fatigue and stabilized the surgeon's hand during ETSS. Shaking of the video image decreased due to the steadying of the surgeon's scope-holding hand with iArmS. There were no complications related to use of the device. Conclusions The intelligent armrest, iArmS, seems to be safe and effective during ETSS. iArmS is helpful for improving the precision and safety not only for microscopic neurosurgery, but also for ETSS. Ongoing advances in robotics ensure the continued evolution of neurosurgery.

Haptic stabilization of posture: changes in arm proprioception and cutaneous feedback for different arm orientations

NASA Technical Reports Server (NTRS)

Rabin, E.; Bortolami, S. B.; DiZio, P.; Lackner, J. R.

1999-01-01

Postural sway during quiet stance is attenuated by actively maintained contact of the index finger with a stationary surface, even if the level of applied force (<1 N) cannot provide mechanical stabilization. In this situation, changes in force level at the fingertip lead changes in center of foot pressure by approximately 250 ms. These and related findings indicate that stimulation of the fingertip combined with proprioceptive information about the hand and arm can serve as an active sensor of body position relative to the point of contact. A geometric analysis of the relationship between hand and torso displacement during body sway led to the prediction that arm and hand proprioceptive and finger somatosensory information about body sway would be maximized with finger contact in the plane of body sway. Therefore, the most postural stabilization should be possible with such contact. To test this analysis, subjects touched a laterally versus anteriorly placed surface while in each of two stances: the heel-to-toe tandem Romberg stance that reduces medial-lateral stability and the heel-to-heel, toes-outward, knees-bent, "duck stance" that reduces fore-aft stability. Postural sway was always least with finger contact in the unstable plane: for the tandem stance, lateral fingertip contact was significantly more effective than frontal contact, and, for the duck stance, frontal contact was more effective than lateral fingertip contact. Force changes at the fingertip led changes in center of pressure of the feet by approximately 250 ms for both fingertip contact locations for both test stances. These results support the geometric analysis, which showed that 1) arm joint angles change by the largest amount when fingertip contact is maintained in the plane of greatest sway, and 2) the somatosensory cues at the fingertip provide both direction and amplitude information about sway when the finger is contacting a surface in the unstable plane.

Haptic stabilization of posture: changes in arm proprioception and cutaneous feedback for different arm orientations.

PubMed

Rabin, E; Bortolami, S B; DiZio, P; Lackner, J R

1999-12-01

Postural sway during quiet stance is attenuated by actively maintained contact of the index finger with a stationary surface, even if the level of applied force (<1 N) cannot provide mechanical stabilization. In this situation, changes in force level at the fingertip lead changes in center of foot pressure by approximately 250 ms. These and related findings indicate that stimulation of the fingertip combined with proprioceptive information about the hand and arm can serve as an active sensor of body position relative to the point of contact. A geometric analysis of the relationship between hand and torso displacement during body sway led to the prediction that arm and hand proprioceptive and finger somatosensory information about body sway would be maximized with finger contact in the plane of body sway. Therefore, the most postural stabilization should be possible with such contact. To test this analysis, subjects touched a laterally versus anteriorly placed surface while in each of two stances: the heel-to-toe tandem Romberg stance that reduces medial-lateral stability and the heel-to-heel, toes-outward, knees-bent, "duck stance" that reduces fore-aft stability. Postural sway was always least with finger contact in the unstable plane: for the tandem stance, lateral fingertip contact was significantly more effective than frontal contact, and, for the duck stance, frontal contact was more effective than lateral fingertip contact. Force changes at the fingertip led changes in center of pressure of the feet by approximately 250 ms for both fingertip contact locations for both test stances. These results support the geometric analysis, which showed that 1) arm joint angles change by the largest amount when fingertip contact is maintained in the plane of greatest sway, and 2) the somatosensory cues at the fingertip provide both direction and amplitude information about sway when the finger is contacting a surface in the unstable plane.

Absence of equifinality of hand position in a double-step unloading task.

PubMed

Norouzi-Gheidari, Nahid; Archambault, Philippe

2010-08-01

Equifinality, during arm reaching movements, relates to the capacity of the neuromuscular system to attain the same final position in the presence or absence of transient perturbations. There have been several controversies regarding equifinality in the literature. A brief elastic perturbation, applied during a fast arm movement or just before its initiation, typically does not affect final arm position. On the other hand, several experiments have shown that velocity-dependent perturbations, such as Coriolis force or negative damping, while transient in nature, have a significant effect on final arm position when compared to unperturbed movements. In this study, an unloading paradigm was used to study the role of reflexes with respect to equifinality. The effects on final arm position of suddenly decreasing a static load maintained by fourteen subjects were analyzed. Subjects maintained an initial load produced by a double-joint manipulandum moving in the horizontal plane. The load was suddenly decreased, either in one or in two successive steps with different time intervals, resulting in a rapid reflex-mediated change in arm position. Unloading led to short-latency changes in the activity of shoulder and elbow muscles and significant variations in tonic activity. It was found that the final hand position was shorter for double- versus single-step unloading if the time between two successive changes in load was greater than 100 ms. With a shorter time interval, the final hand positions were the same. This difference in final hand positions was inversely proportional to the hand velocity at the time of the second change in load. Further, agonist/antagonist co-activation increased in double-step unloading. Thus, the change in both the load and the movement velocity may influence the magnitude of the unloading reflex. This may be indicative of a dependence of stretch reflexes on velocity. Perturbation may cause a reflex-mediated increase in joint stiffness, which

An interactive videogame for arm and hand exercise in people with Parkinson's disease: A randomized controlled trial.

PubMed

Allen, Natalie E; Song, Jooeun; Paul, Serene S; Smith, Stuart; O'Duffy, Jonathan; Schmidt, Matthew; Love, Rachelle; Sherrington, Catherine; Canning, Colleen G

2017-08-01

People with Parkinson's disease (PD) have difficulty performing upper extremity (UE) activities. The aim of this study was to investigate if exergames targeting the UE improve arm and hand activities and impairments and to establish the acceptability and feasibility of these games in people with PD. Two tablet-based exergames were developed which were controlled with finger movements or unimanual whole arm movements. Participants with PD were randomized to an exergame (n = 19) or control (n = 19) group. The exergame group performed UE exergames at home, 3 times per week for 12 weeks. The primary outcome measure was the nine hole peg test. Secondary outcomes included measures of UE activities and impairments, including the tapping test [speed (taps/60s), and error (weighted error score/speed)]. There were no between group differences in the nine hole peg test, or in any secondary outcome measures except for the tapping test. Horizontal tapping test results showed that exergame participants improved their speed (mean difference = 10.9 taps/60s, p < 0.001) but increased error (mean difference = 0.03, p = 0.03) compared to the control group. Participants enjoyed the games and improved in their ability to play the games. There were no adverse events. The UE exergames were acceptable and safe, but did not translate to improvement in functional activities. It is likely that the requirement of the games resulted in increased movement speed at the detriment of accuracy. The design of exergames should consider task specificity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dynamics, control and sensor issues pertinent to robotic hands for the EVA retriever system

NASA Technical Reports Server (NTRS)

Mclauchlan, Robert A.

1987-01-01

Basic dynamics, sensor, control, and related artificial intelligence issues pertinent to smart robotic hands for the Extra Vehicular Activity (EVA) Retriever system are summarized and discussed. These smart hands are to be used as end effectors on arms attached to manned maneuvering units (MMU). The Retriever robotic systems comprised of MMU, arm and smart hands, are being developed to aid crewmen in the performance of routine EVA tasks including tool and object retrieval. The ultimate goal is to enhance the effectiveness of EVA crewmen.

Isolated effects of peripheral arm and central body cooling on arm performance.

PubMed

Giesbrecht, G G; Wu, M P; White, M D; Johnston, C E; Bristow, G K

1995-10-01

correlations indicated that Tes accounted for 4-10% of the variance in scores of 4 tests. We conclude that cooling of the body and/or the arm elicits large decrements in finger, hand and arm performance. The decrements are due almost entirely to the local effects of arm tissue cooling.

Dermatological spectrum of hand, foot and mouth disease from classical to generalized exanthema.

PubMed

Hubiche, Thomas; Schuffenecker, Isabelle; Boralevi, Franck; Léauté-Labrèze, Christine; Bornebusch, Laure; Chiaverini, Christine; Phan, Alice; Maruani, Annabel; Miquel, Juliette; Lafon, Marie-Edith; Lina, Bruno; Del Giudice, Pascal

2014-04-01

Hand, foot and mouth disease (HFMD) is classically defined as a childhood fever accompanied by a rash with vesicles or erosions of the oral mucosa, hands, feet and sometimes the buttocks. Severe neurological complications are associated with enterovirus 71 outbreaks in Asia. Recently, it has been suggested that HFMD is related to coxsackie virus A6 (CV-A6) when there is an atypical rash. The objective of the study is to determine the dermatological pattern of HFMD and to identify the virus serotypes associated with a specific dermatological pattern. A prospective, cross-sectional study was conducted in 7 pediatric dermatology units in France from March 2010 to February 2012. All children with clinically suspected diagnosis of HFMD were included. Clinical data were collected and swabs from the nasopharynx and vesicles were taken for reverse transcription polymerase chain reaction and genotyping. Only children with confirmed HFMD--defined by clinical diagnosis of HFMD and positive enterovirus polymerase chain reaction results--were included for analysis. One hundred and four children consulted for suspected HFMD, including 89 (mean age: 25.7 months; sex ratio M/F 1.54) with confirmed HFMD. Seventy-eight (87.6%) had skin lesions on sites other than hand, feet and mouth. Thirty-seven (41.5%) had 5 or more anatomical sites involved (hand, feet and mouth, buttocks, legs, arms and trunk) considered as widespread exanthema. Widespread vesicular exanthema was observed with both CV-A6 and CV-A16. Peri-oral rash was associated with CV-A6 (P < 0.001). HFMD has a clinical spectrum ranging from classical to generalized vesicular exanthema. Generalized and atypical exanthema were observed with both CV-A6 and CV-A16 infections. CV-A6 is associated with peri-oral rash.

Localized Arm Volume Index: A New Method for Body Type-Corrected Evaluation of Localized Arm Lymphedematous Volume Change.

PubMed

Yamamoto, Takumi; Yamamoto, Nana; Yoshimatsu, Hidehiko

2017-10-01

Volume measurement is a common evaluation for upper extremity lymphedema. However, volume comparison between different patients with different body types may be inappropriate, and it is difficult to evaluate localized limb volume change using arm volume. Localized arm volumes (Vk, k = 1-5) and localized arm volume indices (LAVIk) at 5 points (1, upper arm; 2, elbow; 3, forearm; 4, wrist; 5, hand) of 106 arms of 53 examinees with no arm edema were calculated based on physical measurements (arm circumferences and lengths and body mass index [BMI]). Interrater and intrarater reliabilities of LAVIk were assessed, and Vk and LAVIk were compared between lower BMI (BMI, <22 kg/m) group and higher BMI (BMI, ≥22 kg/m) group. Interrater and intrarater reliabilities of LAVIk were all high (all, r > 0.98). Between lower and higher BMI groups, significant differences were observed in all Vk (V1 [P = 6.8 × 10], V2 [P = 3.1 × 10], V3 [P = 1.1 × 10], V4 [P = 8.3 × 10], and V5 [P = 3.0 × 10]). Regarding localized arm volume index (LAVI) between groups, significant differences were seen in LAVI1 (P = 9.7 × 10) and LAVI5 (P = 1.2 × 10); there was no significant difference in LAVI2 (P = 0.60), LAVI3 (P = 0.61), or LAVI4 (P = 0.22). Localized arm volume index is a convenient and highly reproducible method for evaluation of localized arm volume change, which is less affected by body physique compared with arm volumetry.

Complex Regional Pain Syndrome

MedlinePlus

Complex regional pain syndrome (CRPS) is a chronic pain condition. It causes intense pain, usually in the arms, hands, legs, or feet. ... in skin temperature, color, or texture Intense burning pain Extreme skin sensitivity Swelling and stiffness in affected ...

Costs and outcome for serious hand and arm injuries during the first year after trauma - a prospective study.

PubMed

Rosberg, Hans-Eric; Carlsson, Katarina Steen; Cederlund, Ragnhild I; Ramel, Eva; Dahlin, Lars B

2013-05-24

To study costs and outcome for serious hand and arm injuries during the first year after the trauma. In patients with a Hand Injury Severity Score (HISS) > 50, DASH and EQ-5D scores as well as factors related to costs within the health care sector, costs due to lost production and total costs were evaluated. Cox-regression analysis stratifying for mechanism of injury was used to analyse return to work. The majority of the 45 included patients (median 42 years 16-64) were men with severe (n = 9) or major (n = 36) injuries with different type of injuries (amputations n = 13; complex injuries n = 18; major nerve injuries/full house n = 13; burn injury n = 1). DASH and EQ-5D decreased and increased, respectively, significantly over time during one year. Total costs (+34%) and costs of lost production were highest for persons injured at work. Factors associated with higher health care costs were age >50 years (+52%), injury at work (+40%) and partial labour market activity (+66%). Costs of lost production had a significant role in total costs of injury. Patients with major injuries had longer duration of sick leave. Patients with severe injuries were more likely to return to work [(RR 3.76 (95% CI 1.38-10.22) from Cox regression, controlling for age, gender and presence of nerve injury]. Despite the fact that work environments have constantly improved over the last decades, we found that hand injuries at work were most costly both in terms of health care and costs of lost production, although the severity, i.e. HISS, did not differ from injuries occurring at home or during leisure.

Translational control of a graphically simulated robot arm by kinematic rate equations that overcome elbow joint singularity

NASA Technical Reports Server (NTRS)

Barker, L. K.; Houck, J. A.; Carzoo, S. W.

1984-01-01

An operator commands a robot hand to move in a certain direction relative to its own axis system by specifying a velocity in that direction. This velocity command is then resolved into individual joint rotational velocities in the robot arm to effect the motion. However, the usual resolved-rate equations become singular when the robot arm is straightened. To overcome this elbow joint singularity, equations were developed which allow continued translational control of the robot hand even though the robot arm is (or is nearly) fully extended. A feature of the equations near full arm extension is that an operator simply extends and retracts the robot arm to reverse the direction of the elbow bend (difficult maneuver for the usual resolved-rate equations). Results show successful movement of a graphically simulated robot arm.

A critique of a UK standardized test of finger rewarming after cold provocation in the diagnosis and staging of hand-arm vibration syndrome.

PubMed

Mason, H J; Poole, K; Saxton, J

2003-08-01

Accurate diagnosis and staging of hand-arm vibration syndrome (HAVS) is important in health surveillance of vibration-exposed workers and the substantial number of related medico-legal cases. The measurement of the rewarming rate of fingers after cold provocation to the hands (CPT) has been suggested as a useful test in diagnosing HAVS. To investigate the diagnostic value of a standardized version of the CPT test using a 15 degrees C cold challenge for 5 min applied in the recent compensation assessment of UK miners. Analysis of a subset of UK miners assessed at our unit, together with data from a small repeatability study of the standardized CPT in normal subjects. Rewarming time in the CPT was significantly lower in those subjects classified as vascular Stockholm stage 0 compared with Stockholm stages 1-3 combined, but did not discriminate between the stages of abnormality. Using the suggested cut-off in the CPT test, the sensitivity and specificity were calculated as 43 and 78%, respectively. Receiver operator characteristic analysis suggested that the rewarming time of highest accuracy gave a sensitivity of 66% and specificity of 59%. In 10 miners who reported unilateral hand blanching, there was no significant difference in CPT measurements between blanching and non-blanching hands. Repeat CPT measurements in normal subjects suggested mean differences of 52 and 107 s for each hand, and the Bland-Altman coefficient of repeatability was approximately 600 s for all fingers. Single application of this standardized CPT test may have limited value in diagnosing the vascular component of HAVS in an individual.

Focal dystonia of right hand with mirror movements upon use of left arm.

PubMed

Rana, Abdul Qayyum; Athar, Aysha

2013-05-01

Dystonia is a movement disorder characterized by sustained muscle contractions, causing twisting and repetitive movements or abnormal postures of affected body parts. Here, we present a novel case of focal dystonia of a 51 years old right-handed woman who had developed difficulty in writing and performing fine motor tasks. Due to a discomfort in her right hand at use, she started using her left hand instead and noticed inconsistent mirror movements in her right hand upon use of left hand. She was treated with trihexyphenidyl which allowed her right hand to function better, though writing still remained a problem.

Single-leg squats can predict leg alignment in dancers performing ballet movements in “turnout”

PubMed Central

Hopper, Luke S; Sato, Nahoko; Weidemann, Andries L

2016-01-01

The physical assessments used in dance injury surveillance programs are often adapted from the sports and exercise domain. Bespoke physical assessments may be required for dance, particularly when ballet movements involve “turning out” or external rotation of the legs beyond that typically used in sports. This study evaluated the ability of the traditional single-leg squat to predict the leg alignment of dancers performing ballet movements with turnout. Three-dimensional kinematic data of dancers performing the single-leg squat and five ballet movements were recorded and analyzed. Reduction of the three-dimensional data into a one-dimensional variable incorporating the ankle, knee, and hip joint center positions provided the strongest predictive model between the single-leg squat and the ballet movements. The single-leg squat can predict leg alignment in dancers performing ballet movements, even in “turned out” postures. Clinicians should pay careful attention to observational positioning and rating criteria when assessing dancers performing the single-leg squat. PMID:27895518

Those are Your Legs: The Effect of Visuo-Spatial Viewpoint on Visuo-Tactile Integration and Body Ownership

PubMed Central

Pozeg, Polona; Galli, Giulia; Blanke, Olaf

2015-01-01

Experiencing a body part as one’s own, i.e., body ownership, depends on the integration of multisensory bodily signals (including visual, tactile, and proprioceptive information) with the visual top-down signals from peripersonal space. Although it has been shown that the visuo-spatial viewpoint from where the body is seen is an important visual top-down factor for body ownership, different studies have reported diverging results. Furthermore, the role of visuo-spatial viewpoint (sometime also called first-person perspective) has only been studied for hands or the whole body, but not for the lower limbs. We thus investigated whether and how leg visuo-tactile integration and leg ownership depended on the visuo-spatial viewpoint from which the legs were seen and the anatomical similarity of the visual leg stimuli. Using a virtual leg illusion, we tested the strength of visuo-tactile integration of leg stimuli using the crossmodal congruency effect (CCE) as well as the subjective sense of leg ownership (assessed by a questionnaire). Fifteen participants viewed virtual legs or non-corporeal control objects, presented either from their habitual first-person viewpoint or from a viewpoint that was rotated by 90°(third-person viewpoint), while applying visuo-tactile stroking between the participants legs and the virtual legs shown on a head-mounted display. The data show that the first-person visuo-spatial viewpoint significantly boosts the visuo-tactile integration as well as the sense of leg ownership. Moreover, the viewpoint-dependent increment of the visuo-tactile integration was only found in the conditions when participants viewed the virtual legs (absent for control objects). These results confirm the importance of first person visuo-spatial viewpoint for the integration of visuo-tactile stimuli and extend findings from the upper extremity and the trunk to visuo-tactile integration and ownership for the legs. PMID:26635663

VenUS I: a randomised controlled trial of two types of bandage for treating venous leg ulcers.

PubMed

Iglesias, C; Nelson, E A; Cullum, N A; Torgerson, D J

2004-07-01

To compare the clinical and cost-effectiveness of two different compression bandages for the healing of venous leg ulcers. A pragmatic, randomised controlled trial with an economic evaluation. Community, district nurse-led services; community leg ulcer clinics; hospital leg ulcer clinics with community outreach. A range of urban and rural settings in England and Scotland. Patients with a venous leg ulcer of at least 1-week's duration, at least 1 cm in length or width and an ankle:brachial pressure index of at least 0.8. The four-layer bandage (4LB) (which is multilayer elastic compression) compared with the short-stretch bandage (SSB) (multilayer, inelastic compression). The primary end-point was complete healing of all the ulcers on the trial leg. Secondary outcomes were the proportion of patients healed at 12 and 24 weeks, rate of recurrence, costs of leg ulcer treatment and quality of life. Between April 1999 and December 2000 the trial recruited 387 people aged from 23 to 97 years at trial entry. The majority of patients in this trial (82%; 316/387) had a reference ulcer of area arm is significantly lower than that for people treated with the 4LB. Our base case economic analysis showed that the 4LB is the dominant strategy, that is, it is

Edema

MedlinePlus

Edema Overview Edema is swelling caused by excess fluid trapped in your body's tissues. Although edema can affect any part of your body, you ... in your hands, arms, feet, ankles and legs. Edema can be the result of medication, pregnancy or ...

A comparison of upper limb amputees and patients with upper limb injuries using the Disability of the Arm, Shoulder and Hand (DASH).

PubMed

Davidson, Judith

To use the Disability of the Arm Shoulder and Hand (DASH) scale to measure the disability of patients with upper limb amputation(s) and to compare these to other upper limb injuries. All 274 patients over the age of 18 years presenting to Prince Henry Hospital in Sydney over a 4-year time frame were given the DASH assessment tool and asked to complete it under supervision of the Occupational Therapist. Patients with brachial plexus injuries, Complex Regional Pain Syndrome and bilateral upper limb amputations demonstrated significantly higher levels of disability to patients with unilateral upper limb amputations. Partial hand amputees reported a higher level of disability than major unilateral upper limb amputees. For the 48 patients who completed pre- and post-treatment assessments, there was a significant improvement in their health status. Further research is required to understand the factors that affect a patient's perceptions of their disability. Perhaps the definitive nature of an amputation and the immediate involvement of highly skilled health professionals serve to assist patients to accept their injury and therefore minimizes the level of disability.

The Effect of Playing Different Musical Instruments on Arm Asymmetry

ERIC Educational Resources Information Center

Kaya, E. Erdem

2015-01-01

Between the two hemispheres of the brain, structural and functional differences are called cerebral lateralization that can affect the skill performance of both arms in a different way, which is called handedness. Approximately 90% of people are right-handed and they use the right hand for most skillful activities. Interestingly, recent studies…

Dissociation between neural and vascular responses to sympathetic stimulation : contribution of local adrenergic receptor function

NASA Technical Reports Server (NTRS)

Jacob, G.; Costa, F.; Shannon, J.; Robertson, D.; Biaggioni, I.

2000-01-01

Sympathetic activation produced by various stimuli, eg, mental stress or handgrip, evokes regional vascular responses that are often nonhomogeneous. This phenomenon is believed to be the consequence of the recruitment of differential central neural pathways or of a sympathetically mediated vasodilation. The purpose of this study was to determine whether a similar heterogeneous response occurs with cold pressor stimulation and to test the hypothesis that local differences in adrenergic receptor function could be in part responsible for this diversity. In 8 healthy subjects, local norepinephrine spillover and blood flow were measured in arms and legs at baseline and during sympathetic stimulation induced by baroreflex mechanisms (nitroprusside infusion) or cold pressor stimulation. At baseline, legs had higher vascular resistance (27+/-5 versus 17+/-2 U, P=0.05) despite lower norepinephrine spillover (0.28+/-0.04 versus 0.4+/-0.05 mg. min(-1). dL(-1), P=0.03). Norepinephrine spillover increased similarly in both arms and legs during nitroprusside infusion and cold pressor stimulation. On the other hand, during cold stimulation, vascular resistance increased in arms but not in legs (20+/-9% versus -7+/-4%, P=0.03). Increasing doses of isoproterenol and phenylephrine were infused intra-arterially in arms and legs to estimate beta-mediated vasodilation and alpha-induced vasoconstriction, respectively. beta-Mediated vasodilation was significantly lower in legs compared with arms. Thus, we report a dissociation between norepinephrine spillover and vascular responses to cold stress in lower limbs characterized by a paradoxical decrease in local resistance despite increases in sympathetic activity. The differences observed in adrenergic receptor responses cannot explain this phenomenon.

Restless Legs Syndrome

MedlinePlus

... Legs Syndrome Condition Restless Legs Syndrome Share Print Table of Contents1. Overview2. Symptoms3. Diagnosis4. Treatment5. Questions Overview ... twitch when you try and sleep (also called periodic limb movements of sleep or PLMS). Diagnosis How ...

Cooperative hand movements in post-stroke subjects: Neural reorganization.

PubMed

Schrafl-Altermatt, Miriam; Dietz, Volker

2016-01-01

Recent research indicates a task-specific neural coupling controlling cooperative hand movements reflected in bilateral electromyographic reflex responses in arm muscles following unilateral nerve stimulation. Reorganization of this mechanism was explored in post-stroke patients in this study. Electromyographic reflex responses in forearm muscles to unilateral electrical ulnar nerve stimulation were examined during cooperative and non-cooperative hand movements. Stimulation of the unaffected arm during cooperative hand movements led to electromyographic responses in bilateral forearm muscles, similar to those seen in healthy subjects, while stimulation of the affected side was followed only by ipsilateral responses. No contralateral reflex responses could be evoked in severely affected patients. The presence of contralateral responses correlated with the clinical motor impairment as assessed by the Fugl-Meyer test. The observations suggest that after stroke an impaired processing of afferent input from the affected side leads to a defective neural coupling and is associated with a greater involvement of fiber tracts from the unaffected hemisphere during cooperative hand movements. The mechanism of neural coupling underlying cooperative hand movements is shown to be defective in post-stroke patients. The neural re-organizations observed have consequences for the rehabilitation of hand function. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Occupational Safety. Hand Tools. Pre-Apprenticeship Phase 1 Training.

ERIC Educational Resources Information Center

Lane Community Coll., Eugene, OR.

This self-paced student training module on safety when using hand tools is one of a number of modules developed for Pre-apprenticeship Phase 1 Training. Purpose of the module is to teach students the correct safety techniques for operating common hand- and arm-powered tools, including selection, maintenance, technique, and uses. The module may…

Venous leg ulcers

PubMed Central

2008-01-01

Introduction Leg ulcers usually occur secondary to venous reflux or obstruction, but 20% of people with leg ulcers have arterial disease, with or without venous disorders. Between 1.5 and 3.0/1000 people have active leg ulcers. Prevalence increases with age to about 20/1000 in people aged over 80 years. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of standard treatments, adjuvant treatments, and organisational interventions for venous leg ulcers? What are the effects of interventions to prevent recurrence of venous leg ulcers? We searched: Medline, Embase, The Cochrane Library, and other important databases up to September 2007 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 80 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: compression bandages and stockings, cultured allogenic (single or bilayer) skin replacement, debriding agents, dressings (cellulose, collagen, film, foam, hyaluronic acid-derived, semi-occlusive alginate), hydrocolloid (occlusive) dressings in the presence of compression, intermittent pneumatic compression, intravenous prostaglandin E1, larval therapy, laser treatment (low-level), leg ulcer clinics, multilayer elastic system, multilayer elastomeric (or non-elastomeric) high-compression regimens or bandages, oral treatments (aspirin, flavonoids, pentoxifylline, rutosides, stanozolol, sulodexide, thromboxane alpha2 antagonists, zinc), peri

Intra-rater Reliability of Arm and Hand Muscle Strength Measurements in Persons With Late Effects of Polio.

PubMed

Brogårdh, Christina; Flansbjer, Ulla-Britt; Carlsson, Håkan; Lexell, Jan

2015-10-01

Muscle weakness in the upper limb is common in persons with late effects of polio. To be able to measure muscle strength and follow changes over time, reliable measurements are needed. To evaluate the intra-rater reliability of isometric and isokinetic arm and hand muscle strength measurements in persons with late effects of polio. A test-retest design. A university hospital outpatient clinic. Twenty-eight persons (mean age 68 years, SD 11 years) with late effects of polio in their upper limbs. Isometric shoulder abduction, isokinetic concentric elbow flexion and extension, isometric elbow flexion, and isometric grip strength were measured twice, 14 days apart. Reliability was evaluated with the intra-class correlation coefficient, the mean difference between the test sessions (d¯), together with the 95% confidence intervals for d¯ , the standard error of measurement (SEM and SEM%), the smallest real difference (SRD and SRD%), and Bland-Altman graphs. A fixed dynamometer (Biodex) was used to measure arm strength and an electronic dynamometer (GRIP-it) was used to measure grip strength. Intra-rater reliability was high, with intra-class correlation coefficients between 0.87 and 0.98. The SEM%, representing the smallest change for a group of persons, ranged from 7%-24% for all strength measurements, and the SRD%, representing the smallest change for an individual person, ranged from 20%-67%. Muscle strength in the upper limbs can be reliably measured in persons with late effects of polio. However, the measurement errors indicate that the method is more suitable to detect changes in muscle strength for a group of persons than for an individual person. Copyright © 2015 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Vector-algebra approach to extract Denavit-Hartenberg parameters of assembled robot arms

NASA Technical Reports Server (NTRS)

Barker, L. K.

1983-01-01

The Denavit-Hartenberg parameters characterize the joint axis systems in a robot arm and, naturally, appear in the transformation matrices from one joint axis system to another. These parameters are needed in the control of robot arms and in the passage of sensor information along the arm. This paper presents a vector algebra method to determine these parameters for any assembled robot arm. The idea is to measure the location of the robot hand (or extension) for different joint angles and then use these measurements to calculate the parameters.

Series Elastic Actuators for legged robots

NASA Astrophysics Data System (ADS)

Pratt, Jerry E.; Krupp, Benjamin T.

2004-09-01

Series Elastic Actuators provide many benefits in force control of robots in unconstrained environments. These benefits include high force fidelity, extremely low impedance, low friction, and good force control bandwidth. Series Elastic Actuators employ a novel mechanical design architecture which goes against the common machine design principal of "stiffer is better." A compliant element is placed between the gear train and driven load to intentionally reduce the stiffness of the actuator. A position sensor measures the deflection, and the force output is accurately calculated using Hooke"s Law (F=Kx). A control loop then servos the actuator to the desired output force. The resulting actuator has inherent shock tolerance, high force fidelity and extremely low impedance. These characteristics are desirable in many applications including legged robots, exoskeletons for human performance amplification, robotic arms, haptic interfaces, and adaptive suspensions. We describe several variations of Series Elastic Actuators that have been developed using both electric and hydraulic components.

[Clinical application of three-dimensional O-arm navigation system in treating patients with dystrophic scoliosis secondary to neurofibromatosis type Ⅰ].

PubMed

Liu, Z; Qiu, Y; Li, Y; Zhao, Z H; Wang, B; Zhu, F; Yu, Y; Sun, X; Zhu, Z Z

2017-03-01

Objective: To investigate the clinical outcomes and the accuracy of O-arm-navigation system assisted pedicle screw insertion in dystrophic scoliosis secondary to neurofibromatosis type Ⅰ(NF-1). Methods: A retrospective study was conducted in 41 patients with dystrophic NF-1-associated thoracic scoliosis who were surgically treated at Department of Orthopaedics, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School between June 2012 and October 2014 with more than 18 months follow-up. The patients were then divided into two groups: 18 patients were under the assistance of O-arm-navigation-based pedicle screw insertion (O-arm group) and the remaining 23 patients' pedicle screws insertion were conducted by free-hand (free-hand group). The X-ray and CT were analyzed to investigate the correction rate and safety of pedicle insertion. t -test was used to analyze measurement data and χ(2) test was used to analyze accuracy of screw insertion between the two groups. Results: The mean coronal Cobb angle was 63.2°±8.7° in the O-arm group and 66.9°±7.4° in the free-hand group ( P >0.05), which was then corrected into 23.1°±6.8° and 30.2°±7.6°( t =2.231, P =0.031) after surgery respectively.Operation time was (265.0±70.3)minutes and estimated blood loss was (1 024±465)ml in the O-arm group. Operation time and estimated blood loss was (243.0±49.6)minutes and (1 228±521)ml respectively in the free-hand group, which had no significant difference between the two groups. However, the implant density was higher in the O-arm group than that in the free-hand group ((64.1±10.8)% vs .(44.3±15.3)%)( t =4.652, P =0.000). The O-arm group comprised 122 screws, of which 72.9% were excellent, 22.1% were good and 4.9% were bad. The free-hand group comprised 136 screws and 48.5% of them were excellent, 33.8% were good and 17.6% were bad.Accuracy of pedicle screw insertion was higher in the O-arm group than that in the free-hand group(χ(2

The Rubber Hand Illusion: Feeling of Ownership and Proprioceptive Drift Do Not Go Hand in Hand

PubMed Central

Rohde, Marieke; Di Luca, Massimiliano; Ernst, Marc O.

2011-01-01

In the Rubber Hand Illusion, the feeling of ownership of a rubber hand displaced from a participant's real occluded hand is evoked by synchronously stroking both hands with paintbrushes. A change of perceived finger location towards the rubber hand (proprioceptive drift) has been reported to correlate with this illusion. To measure the time course of proprioceptive drift during the Rubber Hand Illusion, we regularly interrupted stroking (performed by robot arms) to measure perceived finger location. Measurements were made by projecting a probe dot into the field of view (using a semi-transparent mirror) and asking participants if the dot is to the left or to the right of their invisible hand (Experiment 1) or to adjust the position of the dot to that of their invisible hand (Experiment 2). We varied both the measurement frequency (every 10 s, 40 s, 120 s) and the mode of stroking (synchronous, asynchronous, just vision). Surprisingly, with frequent measurements, proprioceptive drift occurs not only in the synchronous stroking condition but also in the two control conditions (asynchronous stroking, just vision). Proprioceptive drift in the synchronous stroking condition is never higher than in the just vision condition. Only continuous exposure to asynchronous stroking prevents proprioceptive drift and thus replicates the differences in drift reported in the literature. By contrast, complementary subjective ratings (questionnaire) show that the feeling of ownership requires synchronous stroking and is not present in the asynchronous stroking condition. Thus, subjective ratings and drift are dissociated. We conclude that different mechanisms of multisensory integration are responsible for proprioceptive drift and the feeling of ownership. Proprioceptive drift relies on visuoproprioceptive integration alone, a process that is inhibited by asynchronous stroking, the most common control condition in Rubber Hand Illusion experiments. This dissociation implies that

Tremor

MedlinePlus

Tremors are unintentional trembling or shaking movements in one or more parts of your body. Most tremors occur in the hands. You can also have arm, head, face, vocal cord, trunk, and leg tremors. Tremors are most common in middle-aged and ...

Cladribine

MedlinePlus

... of the face, arms, hands, feet, ankles, or lower legs; or unusual tiredness or weakness.Keep all appointments with your doctor and the laboratory. Your doctor will order certain tests before, during, and after treatment to check your body's response to cladribine.

Development and Feasibility Assessment of a Rotational Orthosis for Walking with Arm Swing.

PubMed

Fang, Juan; Xie, Qing; Yang, Guo-Yuan; Xie, Le

2017-01-01

Interlimb neural coupling might underlie human bipedal locomotion, which is reflected in the fact that people swing their arms synchronously with leg movement in normal gait. Therefore, arm swing should be included in gait training to provide coordinated interlimb performance. The present study aimed to develop a Rotational Orthosis for Walking with Arm Swing (ROWAS), and evaluate its feasibility from the perspectives of implementation, acceptability and responsiveness. We developed the mechanical structures of the ROWAS system in SolidWorks, and implemented the concept in a prototype. Normal gait data were used as the reference performance of the shoulder, hip, knee and ankle joints of the prototype. The ROWAS prototype was tested for function assessment and further evaluated using five able-bodied subjects for user feedback. The ROWAS prototype produced coordinated performance in the upper and lower limbs, with joint profiles similar to those occurring in normal gait. The subjects reported a stronger feeling of walking with arm swing than without. The ROWAS system was deemed feasible according to the formal assessment criteria.

Development and Feasibility Assessment of a Rotational Orthosis for Walking with Arm Swing

PubMed Central

Fang, Juan; Xie, Qing; Yang, Guo-Yuan; Xie, Le

2017-01-01

Interlimb neural coupling might underlie human bipedal locomotion, which is reflected in the fact that people swing their arms synchronously with leg movement in normal gait. Therefore, arm swing should be included in gait training to provide coordinated interlimb performance. The present study aimed to develop a Rotational Orthosis for Walking with Arm Swing (ROWAS), and evaluate its feasibility from the perspectives of implementation, acceptability and responsiveness. We developed the mechanical structures of the ROWAS system in SolidWorks, and implemented the concept in a prototype. Normal gait data were used as the reference performance of the shoulder, hip, knee and ankle joints of the prototype. The ROWAS prototype was tested for function assessment and further evaluated using five able-bodied subjects for user feedback. The ROWAS prototype produced coordinated performance in the upper and lower limbs, with joint profiles similar to those occurring in normal gait. The subjects reported a stronger feeling of walking with arm swing than without. The ROWAS system was deemed feasible according to the formal assessment criteria. PMID:28203142

[Lower limb salvage with a free fillet fibula flap harvested from the contralateral amputated leg].

PubMed

Bouyer, M; Corcella, D; Forli, A; Mesquida, V; Semere, A; Moutet, F

2015-06-01

We report a unusual case of "fillet flap" to reconstruct the lower limb with the amputated contralateral leg. This kind of procedure was first described by Foucher et al. in 1980 for traumatic hand surgery as the "bank finger". A 34-year-old man suffered a microlight accident with bilateral open legs fractures. A large skin defect of the left leg exposed the ankle, the calcaneus and a non-vascularized part of the tibial nerve (10 cm). The patient came to the OR for surgical debridement and had massive bone resection of the left calcaneus. The right leg showed limited skin defect at the lower part, exposing the medial side of the ankle and a tibial bone defect, measuring 10 cm. Salvage the left leg was impossible due to complex nerve, bones and skin associated injuries, so this leg was sacrificed and used as a donor limb, to harvest a free fibula flap for contralateral tibial reconstruction. At 18 months of follow-up, the patient was very satisfied, the clinical result was very good on both lower limbs and X-rays showed excellent integration of the free fibula flap. The patient had normal dailies occupations, can run and have bicycle sport practice with a functional left leg fit prosthesis. This case showed an original application of the "fillet flap concept" to resolve complex and rare traumatic situations interesting the both lower limbs. In our opinion, this strategy must be a part of the plastic surgeon skills in uncommon situations. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Arm, Leg, and Foot Skin Water in Persons With Diabetes Mellitus (DM) in Relation to HbA1c Assessed by Tissue Dielectric Constant (TDC) Technology Measured at 300 MHz.

PubMed

Mayrovitz, Harvey N; Volosko, Irina; Sarkar, Bansari; Pandya, Naushira

2017-05-01

DM is associated with structural skin changes. However, few studies have investigated changes in dermal water and specifically its relationship to glucose control as measured by HbA1c. Our goal was to test the hypothesis that skin water, assessed by its tissue dielectric constant (TDC), is inversely related to HbA1c. Water content of 3 skin sites (forearm, lower leg, and foot dorsum) of 50 persons with DM was estimated by measuring TDC at 300 MHz. TDC is the ratio of tissue dielectric constant to vacuum and depends on free and bound water in the measured volume. TDC was measured in triplicate to 4 depths, 0.5. 1.5, 2.5, and 5.0 mm to include different skin components. At each site increased measurement depth showed (1) a significant decrease in absolute TDC values and (2) a significant increase in foot-to-arm TDC ratios. TDC values at forearm were shown to be greater than at either leg or foot. However, testing of these 50 patients at 3 sites and 4 skin depths did not show any significant relationship between TDC and HbA1c or fasting glucose. The data indicate no relationship between TDC values, as indices for skin water, and HbA1c or fasting glucose. This implies that skin TDC values to assess skin property features and changes in persons with DM are not sensitive to recent glucose control. Furthermore, the results introduce a newly applied TDC technology useful to assess skin properties of persons with DM.

Effect of armor and carrying load on body balance and leg muscle function.

PubMed

Park, Huiju; Branson, Donna; Kim, Seonyoung; Warren, Aric; Jacobson, Bert; Petrova, Adriana; Peksoz, Semra; Kamenidis, Panagiotis

2014-01-01

This study investigated the impact of weight and weight distribution of body armor and load carriage on static body balance and leg muscle function. A series of human performance tests were conducted with seven male, healthy, right-handed military students in seven garment conditions with varying weight and weight distributions. Static body balance was assessed by analyzing the trajectory of center of plantar pressure and symmetry of weight bearing in the feet. Leg muscle functions were assessed by analyzing the peak electromyography amplitude of four selected leg muscles during walking. Results of this study showed that uneven weight distribution of garment and load beyond an additional 9 kg impaired static body balance as evidenced by increased sway of center of plantar pressure and asymmetry of weight bearing in the feet. Added weight on non-dominant side of the body created greater impediment to static balance. Increased garment weight also elevated peak EMG amplitude in the rectus femoris to maintain body balance and in the medial gastrocnemius to increase propulsive force. Negative impacts on balance and leg muscle function with increased carrying loads, particularly with an uneven weight distribution, should be stressed to soldiers, designers, and sports enthusiasts. Copyright © 2013 Elsevier B.V. All rights reserved.

Increasing trunk flexion transforms human leg function into that of birds despite different leg morphology.

PubMed

Aminiaghdam, Soran; Rode, Christian; Müller, Roy; Blickhan, Reinhard

2017-02-01

Pronograde trunk orientation in small birds causes prominent intra-limb asymmetries in the leg function. As yet, it is not clear whether these asymmetries induced by the trunk reflect general constraints on the leg function regardless of the specific leg architecture or size of the species. To address this, we instructed 12 human volunteers to walk at a self-selected velocity with four postures: regular erect, or with 30 deg, 50 deg and maximal trunk flexion. In addition, we simulated the axial leg force (along the line connecting hip and centre of pressure) using two simple models: spring and damper in series, and parallel spring and damper. As trunk flexion increases, lower limb joints become more flexed during stance. Similar to birds, the associated posterior shift of the hip relative to the centre of mass leads to a shorter leg at toe-off than at touchdown, and to a flatter angle of attack and a steeper leg angle at toe-off. Furthermore, walking with maximal trunk flexion induces right-skewed vertical and horizontal ground reaction force profiles comparable to those in birds. Interestingly, the spring and damper in series model provides a superior prediction of the axial leg force across trunk-flexed gaits compared with the parallel spring and damper model; in regular erect gait, the damper does not substantially improve the reproduction of the human axial leg force. In conclusion, mimicking the pronograde locomotion of birds by bending the trunk forward in humans causes a leg function similar to that of birds despite the different morphology of the segmented legs. © 2017. Published by The Company of Biologists Ltd.

Steerable Hopping Six-Legged Robot

NASA Technical Reports Server (NTRS)

Younse, Paulo; Aghazarian, Hrand

2010-01-01

The figure depicts selected aspects of a six-legged robot that moves by hopping and that can be steered in the sense that it can be launched into a hop in a controllable direction. This is a prototype of hopping robots being developed for use in scientific exploration of rough terrain on remote planets that have surface gravitation less than that of Earth. Hopping robots could also be used on Earth, albeit at diminished hopping distances associated with the greater Earth gravitation. The upper end of each leg is connected through two universal joints to an upper and a lower hexagonal frame, such that the tilt of the leg depends on the relative position of the two frames. Two non-back-driveable worm-gear motor drives are used to control the relative position of the two frames along two axes 120 apart, thereby controlling the common tilt of all six legs and thereby, further, controlling the direction of hopping. Each leg includes an upper and a lower aluminum frame segment with a joint between them. A fiberglass spring, connected via hinges to both segments, is used to store hopping energy prior to launch into a hop and to cushion the landing at the end of the hop. A cable for loading the spring is run into each leg through the center of the universal joints and then down along the center lines of the segments to the lower end of the leg. A central spool actuated by a motor with a harmonic drive and an electromagnetic clutch winds in all six cables to compress all six springs (thereby also flexing all six legs) simultaneously. To ensure that all the legs push off and land in the same direction, timing- belt pulley drives are attached to the leg segments, restricting the flexing and extension of all six legs to a common linear motion. In preparation for a hop, the spool can be driven to load the spring legs by an amount corresponding to a desired hop distance within range. The amount of compression can be computed from the reading of a shaft-angle encoder that

Design and pilot validation of A-gear: a novel wearable dynamic arm support.

PubMed

Kooren, Peter N; Dunning, Alje G; Janssen, Mariska M H P; Lobo-Prat, Joan; Koopman, Bart F J M; Paalman, Micha I; de Groot, Imelda J M; Herder, Just L

2015-09-18

Persons suffering from progressive muscular weakness, like those with Duchenne muscular dystrophy (DMD), gradually lose the ability to stand, walk and to use their arms. This hinders them from performing daily activities, social participation and being independent. Wheelchairs are used to overcome the loss of walking. However, there are currently few efficient functional substitutes to support the arms. Arm supports or robotic arms can be mounted to wheelchairs to aid in arm motion, but they are quite visible (stigmatizing), and limited in their possibilities due to their fixation to the wheelchair. The users prefer inconspicuous arm supports that are comfortable to wear and easy to control. In this paper the design, characterization, and pilot validation of a passive arm support prototype, which is worn on the body, is presented. The A-gear runs along the body from the contact surface between seat and upper legs via torso and upper arm to the forearm. Freedom of motion is accomplished by mechanical joints, which are nearly aligned with the human joints. The system compensates for the arm weight, using elastic bands for static balance, in every position of the arm. As opposed to existing devices, the proposed kinematic structure allows trunk motion and requires fewer links and less joint space without compromising balancing precision. The functional prototype has been validated in three DMD patients, using 3D motion analysis. Measurements have shown increased arm performance when the subjects were wearing the prototype. Upward and forward movements were easier to perform. The arm support is easy to put on and remove. Moreover, the device felt comfortable for the subjects. However, downward movements were more difficult, and the patients would prefer the device to be even more inconspicuous. The A-gear prototype is a step towards inconspicuousness and therefore well-received dynamic arm supports for people with muscular weakness.

Risk Factors for Musculoskeletal Symptoms Among Korean Broadcast Actors.

PubMed

Park, Moon-Hee; Kim, Ham-Gyum; Cho, Jae-Hwan

2015-01-01

Musculoskeletal diseases (MSDs) are functional disabilities in the musculoskeletal area that occur when continuous damage to the muscles or tissues is caused by performing a repetitive task. These diseases are usually found in the waist, shoulder, neck, arm, and wrist. MSD is also referred to as cumulative trauma disorder, repetitive strain injury, occupational overuse syndrome, and visual display terminal, depending on the country. The condition is now commonly referred to as work-related musculoskeletal disorder. The aim of this study was to develop a prevention plan against musculoskeletal disease and to provide better health care to broadcast actors by understanding the association between musculoskeletal symptoms and working conditions. The results of the study can be utilized to maintain effective systematic resources to treat such diseases. A survey was conducted in Seoul between January 1 and May 10, 2014 with broadcast actors working in the South Korean entertainment industry. Tests with respect to musculoskeletal symptoms indicated that the study participants were likely to experience having musculoskeletal symptoms in the shoulders, waist, neck, leg/foot, hand/wrist/finger, and arm/elbow. Most of the participants reported pain on both sides of their shoulders and in their legs/feet or on the right side of the arm/elbow and in hand/wrist/finger. Pain lasted between 1 and 7 days, with an incidence of 33.8% in the neck, 36% in the shoulders, 33.3% in the arm/elbow, 47.4% in the hand/wrist/finger, 34.7% in the waist, and 39.3% in the leg/foot. This study should prove useful in determining systematic and effective resources to prevent broadcast actors from developing MSD in the future. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Effects of Computer-Aided Interlimb Force Coupling Training on Paretic Hand and Arm Motor Control following Chronic Stroke: A Randomized Controlled Trial

PubMed Central

Lin, Chueh-Ho; Chou, Li-Wei; Luo, Hong-Ji; Tsai, Po-Yi; Lieu, Fu-Kong; Chiang, Shang-Lin; Sung, Wen-Hsu

2015-01-01

Objective We investigated the training effects of interlimb force coupling training on paretic upper extremity outcomes in patients with chronic stroke and analyzed the relationship between motor recovery of the paretic hand, arm and functional performances on paretic upper limb. Design A randomized controlled trial with outcome assessment at baseline and after 4 weeks of intervention. Setting Taipei Veterans General Hospital, National Yang-Ming University. Participants Thirty-three subjects with chronic stroke were recruited and randomly assigned to training (n = 16) and control groups (n = 17). Interventions The computer-aided interlimb force coupling training task with visual feedback included different grip force generation methods on both hands. Main Outcome Measures The Barthel Index (BI), the upper extremity motor control Fugl-Meyer Assessment (FMA-UE), the Motor Assessment Score (MAS), and the Wolf Motor Function Test (WMFT). All assessments were executed by a blinded evaluator, and data management and statistical analysis were also conducted by a blinded researcher. Results The training group demonstrated greater improvement on the FMA-UE (p<.001), WMFT (p<.001), MAS (p = .004) and BI (p = .037) than the control group after 4 weeks of intervention. In addition, a moderate correlation was found between the improvement of scores for hand scales of the FMA and other portions of the FMA UE (r = .528, p = .018) or MAS (r = .596, p = .015) in the training group. Conclusion Computer-aided interlimb force coupling training improves the motor recovery of a paretic hand, and facilitates motor control and enhances functional performance in the paretic upper extremity of people with chronic stroke. Trial Registration ClinicalTrials.gov NCT02247674. PMID:26193492

Review and Evaluation of Hand-Arm Coordinate Systems for Measuring Vibration Exposure, Biodynamic Responses, and Hand Forces.

PubMed

Dong, Ren G; Sinsel, Erik W; Welcome, Daniel E; Warren, Christopher; Xu, Xueyan S; McDowell, Thomas W; Wu, John Z

2015-09-01

The hand coordinate systems for measuring vibration exposures and biodynamic responses have been standardized, but they are not actually used in many studies. This contradicts the purpose of the standardization. The objectives of this study were to identify the major sources of this problem, and to help define or identify better coordinate systems for the standardization. This study systematically reviewed the principles and definition methods, and evaluated typical hand coordinate systems. This study confirms that, as accelerometers remain the major technology for vibration measurement, it is reasonable to standardize two types of coordinate systems: a tool-based basicentric (BC) system and an anatomically based biodynamic (BD) system. However, these coordinate systems are not well defined in the current standard. Definition of the standard BC system is confusing, and it can be interpreted differently; as a result, it has been inconsistently applied in various standards and studies. The standard hand BD system is defined using the orientation of the third metacarpal bone. It is neither convenient nor defined based on important biological or biodynamic features. This explains why it is rarely used in practice. To resolve these inconsistencies and deficiencies, we proposed a revised method for defining the realistic handle BC system and an alternative method for defining the hand BD system. A fingertip-based BD system for measuring the principal grip force is also proposed based on an important feature of the grip force confirmed in this study.

Leg Injuries and Disorders

MedlinePlus

... are important for motion and standing. Playing sports, running, falling, or having an accident can damage your legs. Common leg injuries include sprains and strains, joint dislocations, and fractures. ...

Coordination of rapid stepping with arm pointing: anticipatory changes and step adaptation.

PubMed

Yiou, Eric; Schneider, Cyril; Roussel, Didier

2007-06-01

The present study explored whether rapid stepping is influenced by the coordination of an arm pointing task. Nine participants were instructed to (a) point the index finger of the dominant arm towards a target from the standing posture, (b) initiate a rapid forward step with the contralateral leg, and (c) synchronize stepping and pointing (combined task). Force plate and ankle muscle electromyography (EMG) recordings were contrasted between (b) and (c). In the combined task, the arm acceleration trace most often peaked around foot-off, coinciding with a 15% increase in the forward acceleration of the center of gravity (CoG). Backward displacement of the center of foot pressure at foot-off, duration of anticipatory postural adjustments (APAs) and ankle muscle EMG activity remained unchanged. In contrast, durations of swing phase and whole step were reduced and step length was smaller in the combined task. A reduction in the swing phase was correlated with an increased CoG forward acceleration at foot-off. Changes in the biomechanics of step initiation during the combined task might be ascribed to the postural dynamics elicited by arm pointing, and not to a modulation of the step APAs programming.

Towards a Digital Body: The Virtual Arm Illusion

PubMed Central

Slater, Mel; Perez-Marcos, Daniel; Ehrsson, H. Henrik; Sanchez-Vives, Maria V.

2008-01-01

The integration of the human brain with computers is an interesting new area of applied neuroscience, where one application is replacement of a person's real body by a virtual representation. Here we demonstrate that a virtual limb can be made to feel part of your body if appropriate multisensory correlations are provided. We report an illusion that is invoked through tactile stimulation on a person's hidden real right hand with synchronous virtual visual stimulation on an aligned 3D stereo virtual arm projecting horizontally out of their shoulder. An experiment with 21 male participants showed displacement of ownership towards the virtual hand, as illustrated by questionnaire responses and proprioceptive drift. A control experiment with asynchronous tapping was carried out with a different set of 20 male participants who did not experience the illusion. After 5 min of stimulation the virtual arm rotated. Evidence suggests that the extent of the illusion was also correlated with the degree of muscle activity onset in the right arm as measured by EMG during this period that the arm was rotating, for the synchronous but not the asynchronous condition. A completely virtual object can therefore be experienced as part of one's self, which opens up the possibility that an entire virtual body could be felt as one's own in future virtual reality applications or online games, and be an invaluable tool for the understanding of the brain mechanisms underlying body ownership. PMID:18958207

Dependence of muscle moment arms on in-vivo three-dimensional kinematics of the knee

PubMed Central

Navacchia, Alessandro; Kefala, Vasiliki; Shelburne, Kevin B.

2016-01-01

Quantification of muscle moment arms is important for clinical evaluation of muscle pathology and treatment, and for estimating muscle and joint forces in musculoskeletal models. Moment arms estimated with musculoskeletal models often assume a default motion of the knee derived from measurements of passive cadaveric flexion. However, knee kinematics are unique to each person and activity. The objective of this study was to estimate moment arms of the knee muscles with in vivo subject- and activity-specific kinematics from seven healthy subjects performing seated knee extension and single-leg lunge to show changes between subjects and activities. 3D knee motion was measured with a high-speed stereo-radiography system. Moment arms of ten muscles were estimated in OpenSim by replacing the default knee motion with in vivo measurements. Estimated inter-subject moment arm variability was similar to previously reported in vitro measurements. RMS deviations up to 9.0 mm (35.2% of peak value) were observed between moment arms estimated with subject-specific knee extension and passive cadaveric motion. The degrees of freedom that most impacted inter-activity differences were superior/inferior and anterior/posterior translations. Musculoskeletal simulations used to estimate in vivo muscle forces and joint loads may provide significantly different results when subject- and activity-specific kinematics are implemented. PMID:27620064

Dependence of Muscle Moment Arms on In Vivo Three-Dimensional Kinematics of the Knee.

PubMed

Navacchia, Alessandro; Kefala, Vasiliki; Shelburne, Kevin B

2017-03-01

Quantification of muscle moment arms is important for clinical evaluation of muscle pathology and treatment, and for estimating muscle and joint forces in musculoskeletal models. Moment arms estimated with musculoskeletal models often assume a default motion of the knee derived from measurements of passive cadaveric flexion. However, knee kinematics are unique to each person and activity. The objective of this study was to estimate moment arms of the knee muscles with in vivo subject- and activity-specific kinematics from seven healthy subjects performing seated knee extension and single-leg lunge to show changes between subjects and activities. 3D knee motion was measured with a high-speed stereo-radiography system. Moment arms of ten muscles were estimated in OpenSim by replacing the default knee motion with in vivo measurements. Estimated inter-subject moment arm variability was similar to previously reported in vitro measurements. RMS deviations up to 9.0 mm (35.2% of peak value) were observed between moment arms estimated with subject-specific knee extension and passive cadaveric motion. The degrees of freedom that most impacted inter-activity differences were superior/inferior and anterior/posterior translations. Musculoskeletal simulations used to estimate in vivo muscle forces and joint loads may provide significantly different results when subject- and activity-specific kinematics are implemented.

Telerobotic control of a dextrous manipulator using master and six-DOF hand-controllers for space assembly and servicing tasks

NASA Technical Reports Server (NTRS)

O'Hara, John M.

1987-01-01

Two studies were conducted evaluating methods of controlling a telerobot; bilateral force reflecting master controllers and proportional rate six degrees of freedom (DOF) hand controllers. The first study compared the controllers on performance of single manipulator arm tasks, a peg-in-the-hole task, and simulated satellite orbital replacement unit changeout. The second study, a Space Station truss assembly task, required simultaneous operation of both manipulator arms (all 12 DOFs) and complex multiaxis slave arm movements. Task times were significantly longer and fewer errors were committed with the hand controllers. The hand controllers were also rated significantly higher in cognitive and manual control workload on the two-arm task. The master controllers were rated significantly higher in physical workload. There were no significant differences in ratings of manipulator control quality.

Spoken language and arm gestures are controlled by the same motor control system.

PubMed

Gentilucci, Maurizio; Dalla Volta, Riccardo

2008-06-01

Arm movements can influence language comprehension much as semantics can influence arm movement planning. Arm movement itself can be used as a linguistic signal. We reviewed neurophysiological and behavioural evidence that manual gestures and vocal language share the same control system. Studies of primate premotor cortex and, in particular, of the so-called "mirror system", including humans, suggest the existence of a dual hand/mouth motor command system involved in ingestion activities. This may be the platform on which a combined manual and vocal communication system was constructed. In humans, speech is typically accompanied by manual gesture, speech production itself is influenced by executing or observing transitive hand actions, and manual actions play an important role in the development of speech, from the babbling stage onwards. Behavioural data also show reciprocal influence between word and symbolic gestures. Neuroimaging and repetitive transcranial magnetic stimulation (rTMS) data suggest that the system governing both speech and gesture is located in Broca's area. In general, the presented data support the hypothesis that the hand motor-control system is involved in higher order cognition.

Hand washing with soap and water together with behavioural recommendations prevents infections in common work environment: an open cluster-randomized trial.

PubMed

Savolainen-Kopra, Carita; Haapakoski, Jaason; Peltola, Piia A; Ziegler, Thedi; Korpela, Terttu; Anttila, Pirjo; Amiryousefi, Ali; Huovinen, Pentti; Huvinen, Markku; Noronen, Heikki; Riikkala, Pia; Roivainen, Merja; Ruutu, Petri; Teirilä, Juha; Vartiainen, Erkki; Hovi, Tapani

2012-01-16

Hand hygiene is considered as an important means of infection control. We explored whether guided hand hygiene together with transmission-limiting behaviour reduces infection episodes and lost days of work in a common work environment in an open cluster-randomized 3-arm intervention trial. A total of 21 clusters (683 persons) were randomized to implement hand hygiene with soap and water (257 persons), with alcohol-based hand rub (202 persons), or to serve as a control (224 persons). Participants in both intervention arms also received standardized instructions on how to limit the transmission of infections. The intervention period (16 months) included the emergence of the 2009 influenza pandemic and the subsequent national hand hygiene campaign influencing also the control arm. In the total follow-up period there was a 6.7% reduction of infection episodes in the soap-and water arm (p = 0.04). Before the onset of the anti-pandemic campaign, a statistically significant (p = 0.002) difference in the mean occurrence of infection episodes was observed between the control (6.0 per year) and the soap-and-water arm (5.0 per year) but not between the control and the alcohol-rub arm (5.6 per year). Neither intervention had a decreasing effect on absence from work. We conclude that intensified hand hygiene using water and soap together with behavioural recommendations can reduce the occurrence of self-reported acute illnesses in common work environment. Surprisingly, the occurrence of reported sick leaves also increased in the soap-and water-arm. ClinicalTrials.gov: NCT00981877 The Finnish Work Environment Fund and the National Institute for Health and Welfare.

Equal vibrotactile sense thresholds of the fingers and its diagnostic significance for hand-arm vibration syndrome.

PubMed

Cheng, H; Zhang, X C; Duan, L; Ma, Y; Wang, J X

1995-01-01

The vibrotactile sense thresholds (VSTs) of the middle fingers of 60 healthy persons and 97 patients with Hand-Arm Vibration Syndrome (HAVS) or subclinical HAVS were measured quantitatively. Intermittent vibratory irritations were adopted, with vibration stimulus frequencies at 8, 16, 31.5, 63, 125, 250, and 500 Hz. The equal VST contours of the fingers were mapped. Results showed that the VSTs of the normal group were not correlated with sex or handedness. From 8 Hz to 250 Hz the equal VST contours of the normal group were relatively flat; at more than 250 Hz the contours began an abrupt ascent. The VST values had a logarithmic rising tendency with the increasing age of subjects. In the equal VST contours the frequency of the most sensitive threshold value was 125 Hz in the normal group and 8 Hz in the HAVS group. The patients' VST values were higher than that of the healthy persons. The vibrotactilegram showed that the VST values of the patient groups first shifted at high frequencies and VST loss displayed a "V"-type hollow at 125 Hz and 250 Hz. The quantitative test method of VST was a valuable auxiliary detection method for HAVS. The "V"-type hollow of VST was an early clinical manifestation of HAVS.

Robust coordinated control of a dual-arm space robot

NASA Astrophysics Data System (ADS)

Shi, Lingling; Kayastha, Sharmila; Katupitiya, Jay

2017-09-01

Dual-arm space robots are more capable of implementing complex space tasks compared with single arm space robots. However, the dynamic coupling between the arms and the base will have a serious impact on the spacecraft attitude and the hand motion of each arm. Instead of considering one arm as the mission arm and the other as the balance arm, in this work two arms of the space robot perform as mission arms aimed at accomplishing secure capture of a floating target. The paper investigates coordinated control of the base's attitude and the arms' motion in the task space in the presence of system uncertainties. Two types of controllers, i.e. a Sliding Mode Controller (SMC) and a nonlinear Model Predictive Controller (MPC) are verified and compared with a conventional Computed-Torque Controller (CTC) through numerical simulations in terms of control accuracy and system robustness. Both controllers eliminate the need to linearly parameterize the dynamic equations. The MPC has been shown to achieve performance with higher accuracy than CTC and SMC in the absence of system uncertainties under the condition that they consume comparable energy. When the system uncertainties are included, SMC and CTC present advantageous robustness than MPC. Specifically, in a case where system inertia increases, SMC delivers higher accuracy than CTC and costs the least amount of energy.

Development of Pneumatic Robot Hand and Construction of Master-Slave System

NASA Astrophysics Data System (ADS)

Tsujiuchi, Nobutaka; Koizumi, Takayuki; Nishino, Shinya; Komatsubara, Hiroyuki; Kudawara, Tatsuwo; Hirano, Masanori

Recently, research and development has focused on robots that work in place of people. It is necessary for robots to perform the same flexible motions as people. Additionally, such robots need to incorporate high-level safety features in order not to injure people. For creation of such robots, we need to develop a robot hand that functions like a human hand. At the same time, this type of robot hand can be used as an artificial hand. Here, we present artificial muscle-type pneumatic actuators as the driving source of a robot hand that is both safe and flexible. Some development of robot hands using pneumatic actuators has already taken place. But, until now, when a pneumatic actuator is used, a big compressor is needed. So, the driving system also needs to be big; enlargement of the driving system is a major problem. Consequently, in this research, we develop a low-pressure, low-volume pneumatic actuator for driving a robot hand that works flexibly and safely on the assumption that it will be in contact with people. We develop a five-fingered robot hand with pneumatic actuators. And, we construct a master-slave system to enable the robot hand to perform the same operations as a human hand. We make a 1-link arm that has one degree of freedom using a pneumatic actuator, and construct a control system for the 1-link arm and verify its control performance.

Athletes' leg pains.

PubMed Central

Orava, S.; Puranen, J.

1979-01-01

The frequency and nature of exertion pains of the leg in athletes were studied in 2,750 cases of overuse injuries treated at the Sports Clinic of the Deaconess Institute of Oulu, Finland, during the years 1972-1977. 465 cases of exertion pain (18%) were located in the shin. The medial tibial syndrome was the most common overuse injury among these athletes, comprising 9.5% of all exertion injuries and 60% of the leg exertion pains. Together with stress fracture of the tibia, the second most common exertion pain of the leg, it accounted for 75% of the total leg pains. There are certain difficulties in differentiating between the medial tibial syndrome and stress fracture of the tibia. They both occur at the same site with similar symptoms. Radiological examination and isotope scanning are needed. The medial tibial syndrome is an overuse injury at the medial tibial border caused by running exercises. The pain is elicited by exertional ischaemia. The pathogenesis is explained by increased pressure in the fascial compartment of the deep flexor muscles due to prolonged exercise. Similar chronic ischaemic pains from exercise are also found in other fascial compartments of the leg, especially in the anterior compartment. The only treatment needed for stress fractures is rest from training. Fascial compartment pains also usually subside. If chronic fascial syndromes prevent training, fasciotomy is recommended as a reliable method to restore the athlete to normal training without pains. PMID:486888

Ballistic movements of jumping legs implemented as variable components of cricket behaviour.

PubMed

Hustert, R; Baldus, M

2010-12-01

Ballistic accelerations of a limb or the whole body require special joint mechanisms in many animals. Specialized joints can be moved by stereotypic or variable motor control during motor patterns with and without ballistic components. As a model of variable motor control, the specialized femur-tibia (knee) joints of cricket (Acheta domesticus) hindlegs were studied during ballistic kicking, jumping and swimming and in non-ballistic walking. In this joint the tendons of the antagonistic flexor and the extensor muscles attach at different distances from the pivot and the opposed lever arms form an angle of 120 deg. A 10:1 ratio of their effective lever arms at full knee flexion helps to prepare for most ballistic extensions: the tension of the extensor can reach its peak while it is restrained by flexor co-contraction. In kicks, preparatory flexion is rapid and the co-contraction terminates just before knee extensions. Therefore, mainly the stored tension of the extensor muscle accelerates the small mass of the tibia. Jumps are prepared with slower extensor-flexor co-contractions that flex both knees simultaneously and then halt to rotate both legs outward to a near horizontal level. From there, catapult extension of both knees accelerates the body, supported by continued high frequency motor activity to their tibia extensor muscles during the ongoing push-off from the substrate. Premature extension of one knee instantly takes load from the lagging leg that extends and catches up, which finally results in a straight jump. In swimming, synchronous ballistic power strokes of both hindlegs drive the tibiae on a ventral-to-posterior trajectory through the water, well coordinated with the swimming patterns of all legs. In walking, running and climbing the steps of the hindlegs range between 45 deg flexion and 125 deg extension and use non-ballistic, alternating activity of knee flexor and extensor muscles. Steep climbing requires longer bursts from the extensor tibiae

Intramuscular pressures beneath elastic and inelastic leggings

NASA Technical Reports Server (NTRS)

Murthy, G.; Ballard, R. E.; Breit, G. A.; Watenpaugh, D. E.; Hargens, A. R.

1994-01-01

Leg compression devices have been used extensively by patients to combat chronic venous insufficiency and by astronauts to counteract orthostatic intolerance following spaceflight. However, the effects of elastic and inelastic leggings on the calf muscle pump have not been compared. The purpose of this study was to compare in normal subjects the effects of elastic and inelastic compression on leg intramuscular pressure (IMP), an objective index of calf muscle pump function. IMP in soleus and tibialis anterior muscles was measured with transducer-tipped catheters. Surface compression between each legging and the skin was recorded with an air bladder. Subjects were studied under three conditions: (1) control (no legging), (2) elastic legging, and (3) inelastic legging. Pressure data were recorded for each condition during recumbency, sitting, standing, walking, and running. Elastic leggings applied significantly greater surface compression during recumbency (20 +/- 1 mm Hg, mean +/- SE) than inelastic leggings (13 +/- 2 mm Hg). During recumbency, elastic leggings produced significantly higher soleus IMP of 25 +/- 1 mm Hg and tibialis anterior IMP of 28 +/- 1 mm Hg compared to 17 +/- 1 mm Hg and 20 +/- 2 mm Hg, respectively, generated by inelastic leggings and 8 +/- 1 mm Hg and 11 +/- 1 mm Hg, respectively, without leggings. During sitting, walking, and running, however, peak IMPs generated in the muscular compartments by elastic and inelastic leggings were similar. Our results suggest that elastic leg compression applied over a long period in the recumbent posture may impede microcirculation and jeopardize tissue viability.(ABSTRACT TRUNCATED AT 250 WORDS).

Reticulate acropigmentation of dohi: a case report with insight into genodermatoses with mottled pigmentation.

PubMed

Mohana, Deepak; Verma, Ujjwala; Amar, Amarkant Jha; Choudhary, R K P

2012-01-01

Reticulate acropigmentation of Dohi also called dyschromatosis symmetrica hereditaria or symmetrical dyschromatosis of the extremities is an autosomal dominant inherited disorder. It is characterized by mottled pigmentation with patchy depigmentation commonly over the back of the hands and feet and sometimes on the arms and legs.

Noise and hand-arm vibration exposure in relation to the risk of hearing loss.

PubMed

Pettersson, Hans; Burström, Lage; Hagberg, Mats; Lundström, Ronnie; Nilsson, Tohr

2012-01-01

The aim of this study was to examine the possible association of combined exposure of noise and hand-arm vibration (HAV) and the risk of noise-induced hearing loss. Workers in a heavy engineering industry were part of a dynamic cohort. Of these workers, 189 had HAV exposure, and their age and hearing status were recorded in the same year and were, therefore, included in the analysis. Data on HAV duration and acceleration was gathered through questionnaires, observations, and measurements. All available audiograms were categorized into normal and hearing loss. The first exposure variable included the lifetime HAV exposure. The lifetime HAV exposure was multiplied by the acceleration of HAV for the second and third exposure variable. Logistic regression using the Generalized Estimation Equations method was chosen to analyze the data to account for the repeated measurements. The analysis was performed with both continuous exposure variables and with exposure variables grouped into exposure quartiles with hearing loss as an outcome and age as a covariate. With continuous exposure variables, the odds ratio (OR) with a 95% confidence interval (CI) for hearing loss was equal to or greater than one for all exposure variables. When the exposure variables were grouped into quartiles, the OR with a 95% CI was greater than one at the third and fourth quartile. The results show that working with vibrating machines in an environment with noise exposure increases the risk of hearing loss, supporting an association between exposure to noise and HAV, and the noise-induced hearing loss.

The future of U.S.-Russia nuclear arms control

NASA Astrophysics Data System (ADS)

Pifer, Steven

2017-11-01

Nuclear arms control has long made contributions to U.S.-Soviet and U.S.-Russian security, but the current regime is at risk. The 1987 Intermediate-range Nuclear Forces Treaty may be headed for collapse. Both the United States and Russia are modernizing their strategic forces, and the fate of the 2010 New Strategic Arms Reduction Treaty is unclear. In the unlikely case that the sides are prepared to go beyond New START, there are ways to address further reductions and related issues. A collapse of the arms control regime, on the other hand, would mean the end of constraints on U.S. and Russian nuclear forces, a significant loss of transparency, and potential costs to U.S. security.

Towards Development of Robotic Aid for Rehabilitation of Locomotion-Impaired Subjects

NASA Technical Reports Server (NTRS)

Bejczy, Antal K.

2000-01-01

Manual assistance of therapists to help movement of legs of spinal cord injured (SCI) subjects during stepping on a treadmill for locomotion rehabilitation has severe economic and technical limitations. Scientists at the Department of Physiological Science at the University of California Los Angeles (UCLA) and roboticists at the Jet Propulsion Laboratory (JPL) initiated a joint effort to develop a robotic mechanism capable of performing controlled motions equivalent to the arm and hand motions of therapists assisting the stepping of locomotion impaired subjects on a treadmill, while the subjects' body weight is partially supported by an overhead harness. A first necessary technical step towards this development is to measure and understand the kinematics and dynamics of the therapists' arm and hand motions as they are reflected on the subjects' leg movement. This paper describes an initial measurement system developed for this purpose together with the related measurement results, and outlines the planned future technical work.

Reduced asymmetry in motor skill learning in left-handed compared to right-handed individuals.

PubMed

McGrath, Robert L; Kantak, Shailesh S

2016-02-01

Hemispheric specialization for motor control influences how individuals perform and adapt to goal-directed movements. In contrast to adaptation, motor skill learning involves a process wherein one learns to synthesize novel movement capabilities in absence of perturbation such that they are performed with greater accuracy, consistency and efficiency. Here, we investigated manual asymmetry in acquisition and retention of a complex motor skill that requires speed and accuracy for optimal performance in right-handed and left-handed individuals. We further determined if degree of handedness influences motor skill learning. Ten right-handed (RH) and 10 left-handed (LH) adults practiced two distinct motor skills with their dominant or nondominant arms during separate sessions two-four weeks apart. Learning was quantified by changes in the speed-accuracy tradeoff function measured at baseline and one-day retention. Manual asymmetry was evident in the RH group but not the LH group. RH group demonstrated significantly greater skill improvement for their dominant-right hand than their nondominant-left hand. In contrast, for the LH group, both dominant and nondominant hands demonstrated comparable learning. Less strongly-LH individuals (lower EHI scores) exhibited more learning of their dominant hand. These results suggest that while hemispheric specialization influences motor skill learning, these effects may be influenced by handedness. Copyright © 2015 Elsevier B.V. All rights reserved.

Defensive peripersonal space: the blink reflex evoked by hand stimulation is increased when the hand is near the face.

PubMed

Sambo, C F; Liang, M; Cruccu, G; Iannetti, G D

2012-02-01

Electrical stimulation of the median nerve at the wrist may elicit a blink reflex [hand blink reflex (HBR)] mediated by a neural circuit at brain stem level. As, in a Sherringtonian sense, the blink reflex is a defensive response, in a series of experiments we tested, in healthy volunteers, whether and how the HBR is modulated by the proximity of the stimulated hand to the face. Electromyographic activity was recorded from the orbicularis oculi, bilaterally. We observed that the HBR is enhanced when the stimulated hand is inside the peripersonal space of the face, compared with when it is outside, irrespective of whether the proximity of the hand to the face is manipulated by changing the position of the arm (experiment 1) or by rotating the head while keeping the arm position constant (experiment 3). Experiment 2 showed that such HBR enhancement has similar magnitude when the participants have their eyes closed. Experiments 4 and 5 showed, respectively, that the blink reflex elicited by the electrical stimulation of the supraorbital nerve, as well as the N20 wave of the somatosensory evoked potentials elicited by the median nerve stimulation, are entirely unaffected by hand position. Taken together, our results provide compelling evidence that the brain stem circuits mediating the HBR in humans undergo tonic and selective top-down modulation from higher order cortical areas responsible for encoding the location of somatosensory stimuli in external space coordinates. These findings support the existence of a "defensive" peripersonal space, representing a safety margin advantageous for survival.

Hand washing with soap and water together with behavioural recommendations prevents infections in common work environment: an open cluster-randomized trial

PubMed Central

2012-01-01

Background Hand hygiene is considered as an important means of infection control. We explored whether guided hand hygiene together with transmission-limiting behaviour reduces infection episodes and lost days of work in a common work environment in an open cluster-randomized 3-arm intervention trial. Methods A total of 21 clusters (683 persons) were randomized to implement hand hygiene with soap and water (257 persons), with alcohol-based hand rub (202 persons), or to serve as a control (224 persons). Participants in both intervention arms also received standardized instructions on how to limit the transmission of infections. The intervention period (16 months) included the emergence of the 2009 influenza pandemic and the subsequent national hand hygiene campaign influencing also the control arm. Results In the total follow-up period there was a 6.7% reduction of infection episodes in the soap-and water arm (p = 0.04). Before the onset of the anti-pandemic campaign, a statistically significant (p = 0.002) difference in the mean occurrence of infection episodes was observed between the control (6.0 per year) and the soap-and-water arm (5.0 per year) but not between the control and the alcohol-rub arm (5.6 per year). Neither intervention had a decreasing effect on absence from work. Conclusions We conclude that intensified hand hygiene using water and soap together with behavioural recommendations can reduce the occurrence of self-reported acute illnesses in common work environment. Surprisingly, the occurrence of reported sick leaves also increased in the soap-and water-arm. Trial Registration ClinicalTrials.gov: NCT00981877 Source of funding The Finnish Work Environment Fund and the National Institute for Health and Welfare. PMID:22243622

Effect of afferent feedback and central motor commands on soleus H-reflex suppression during arm cycling.

PubMed

Hundza, S R; de Ruiter, Geoff C; Klimstra, M; Zehr, E Paul

2012-12-01

Suppression of soleus H-reflex amplitude in stationary legs is seen during rhythmic arm cycling. We examined the influence of various arm-cycling parameters on this interlimb reflex modulation to determine the origin of the effect. We previously showed the suppression to be graded with the frequency of arm cycling but not largely influenced by changes in peripheral input associated with crank length. Here, we more explicitly explored the contribution of afferent feedback related to arm movement on the soleus H-reflex suppression. We explored the influence of load and rate of muscle stretch by manipulating crank-load and arm-muscle vibration during arm cycling. Furthermore, internally driven ("Active") and externally driven ("Passive") arm cycling was compared. Soleus H-reflexes were evoked with tibial nerve stimulation during stationary control and rhythmic arm-cycling conditions, including: 1) six different loads; 2) with and without vibration to arm muscles; and 3) Active and Passive conditions. No significant differences were seen in the level of suppression between the different crank loads or between conditions with and without arm-muscle vibration. Furthermore, in contrast to the clear effect seen during active cycling, passive arm cycling did not significantly suppress the soleus H-reflex amplitude. Current results, in conjunction with previous findings, suggest that the afferent feedback examined in these studies is not the primary source responsible for soleus H-reflex suppression. Instead, it appears that central motor commands (supraspinal or spinal in origin) associated with frequency of arm cycling are relatively more dominant sources.

The Influences of Arm Resist Motion on a CAR Crash Test Using Hybrid III Dummy with Human-Like Arm

NASA Astrophysics Data System (ADS)

Kim, Yongchul; Youm, Youngil; Bae, Hanil; Choi, Hyeonki

Safety of the occupant during the crash is very essential design element. Many researches have been investigated in reducing the fatal injury of occupant. They are focusing on the development of a dummy in order to obtain the real human-like motion. However, they have not considered the arm resist motion during the car accident. In this study, we would like to suggest the importance of the reactive force of the arm in a car crash. The influences of reactive force acting on the human upper extremity were investigated using the impedance experimental method with lumped mass model of hand system and a Hybrid III dummy with human-like arm. Impedance parameters (e.g. inertia, spring constant and damping coefficient) of the elbow joint in maximum activation level were measured by free oscillation test using single axis robot. The results showed that without seat belt, the reactive force of human arm reduced the head, chest, and femur injury, and the flexion moment of the neck is higher than that of the conventional dummy.

Static balance according to hip joint angle of unsupported leg during one-leg standing.

PubMed

Cha, Ju-Hyung; Kim, Jang-Joon; Ye, Jae-Gwan; Lee, Seul-Ji; Hong, Jeong-Mi; Choi, Hyun-Kyu; Choi, Ho-Suk; Shin, Won-Seob

2017-05-01

[Purpose] This study aimed to determine static balance according to hip joint angle of the unsupported leg during one-leg standing. [Subjects and Methods] Subjects included 45 healthy adult males and females in their 20s. During one-leg standing on the non-dominant leg, the position of the unsupported leg was classified according to hip joint angles of point angle was class. Static balance was then measured using a force plate with eyes open and closed. The total length, sway velocity, maximum deviation, and velocity on the mediolateral and anteroposterior axes of center of pressure were measured. [Results] In balance assessment with eyes open, there were significant differences between groups according to hip joint angle, except for maximum deviation on the anteroposterior axis. In balance assessment with eyes closed, there were significant differences between total length measurements at 0° and 30°, 60° and between 30° and 90°. There were significant differences between sway velocity measurements at 0° and 30° and between 30° and 90°. [Conclusion] Thus, there were differences in static balance according to hip joint angle. It is necessary to clearly identify the hip joint angle during one-leg standing testing.

Bio-electrical impedance spectroscopy: alternatives for the conventional hand-to-foot measurements.

PubMed

Cox-Reijven, P L M; Van Kreel, B; Soeters, P B

2002-04-01

Bio-impedance spectroscopy (BIS) is a very attractive method for measuring body composition. The standard method measures impedance from hand to foot. However, in patients a hand or foot is not always accessible. In these cases alternative methods would be helpful. The objective of this study was to compare BIS measurements from hand to foot (HF) with foot to foot (FF) and hand to hand (HH) measurements as alternatives. Aims were firstly, to assess the relationship between resistance (R) values measured by the different methods, secondly, to study the influence of body geometry on this relationship and lastly, to assess the predictive capacity of the methods for measuring body fluid volumes. In 53 subjects with different degrees of obesity (mean BMI = 38; SD = 9 kg/m(2)) three BIS measurements were performed from HF, HH and FF with a Xitron 4000B machine. Resistances of extracellular (Recw) and intracellular water (Ricw) were extrapolated by fitting the data to a Cole-Cole plot. Total body water (TBW) and extracellular water (ECW) were measured by deuterium and bromide dilution respectively. Intracellular water (ICW) was calculated as TBW-ECW. Anthropometric measurements, including length and circumference of limbs and trunk, were performed as measures for body geometry. The Recw, Ricw and R50 values of HF measurements could be accurately described as a function of the Recw, Ricw and R50 values of HH or FF measurements. The relative circumference of arms and legs and the length of the trunk influenced the relationship between R values of the three different measurements. The degree of overweight did not affect this relationship. The precision of the predictions of TBW, ECW and ICW based on R values of the HH measurements were comparable with the traditional HF measurements while the FF measurements gave slightly less accurate results. Under circumstances where total body BIS measurements cannot be performed, FF or HH measurements may be used as alternatives

Cold-provocation testing for the vascular component of hand-arm vibration syndrome in health surveillance.

PubMed

Poole, Kerry; Elms, Joanne; Mason, Howard

2006-10-01

The aim was to investigate whether the use of infra-red thermography (I-R) and measurement of temperature gradients along the finger could improve the diagnostic accuracy of cold-provocation testing (15 degrees C for 5 min) in vascular hand-arm vibration syndrome (HAVS). Twenty-one controls and 33 individuals with stages 2/3V HAVS were studied. The standard measurement of time to rewarm by 4 degrees C (T4 degrees C) and temperature gradients between the finger tip, base and middle (measured using I-R) were calculated. Receiver Operating Characteristics (ROC) analysis to distinguish between the two groups revealed that for T4 degrees C the area under the ROC curve was not statistically significantly different from 0.5 (0.64 95% confidence interval 0.49-0.76). The difference between the tip and middle portion of the finger during the sixth minute of recovery was the most promising gradient with an area of 0.76 (95% confidence interval 0.62-0.87), and sensitivity and specificity of 57.6% and 85.7% respectively. However, this was not significantly different from that for the time to rewarm by 4 degrees C. In conclusion, the cold-provocation test used in this study does not appear to discriminate between individuals with stage 2/3V HAVS and controls and this is not improved by the measurement of temperature gradients along the fingers using I-R.

[Measurement of external pressure of peroneal nerve tract coming in contact with lithotomy leg holders using pressure distribution measurement system BIG-MAT®].

PubMed

Mizuno, Ju; Namba, Chikara; Takahashi, Toru

2014-10-01

We investigated external pressure on peroneal nerve tract coming in contact with two kinds of leg holders using pressure distribution measurement system BIG- MAT® (Nitta Corp., Osaka) in the lithotomy position Peak contact (active) pressure at the left fibular head region coming in contact with knee-crutch-type leg holder M® (Takara Belmont Corp., Osaka), which supports the left popliteal fossa, was 78.0 ± 26.4 mmHg. On the other hand, peak contact pressure at the left lateral lower leg region coming in contact with boot-support-type leg holder Bel Flex® (Takara Belmont Corp., Osaka), which supports the left lower leg and foot was 26.3±7.9 mmHg. These results suggest that use of knee-crutch-type leg holder is more likely to induce common peroneal nerve palsy at the fibular head region, but use of boot-support-type leg holder dose not easily induce superficial peroneal nerve palsy at the lateral lower leg region, because capillary blood pressure is known to be 32 mmHg. Safer holders for positioning will be developed to prevent nerve palsy based on the analysis of chronological change in external pressure using BIG-MAT® system during anesthesia.

Ready steady push--a study of the role of arm posture in manual exertions.

PubMed

Okunribido, Olanrewaju O; Haslegrave, Christine M

2008-02-01

This study investigated arm posture and hand forces during bi-manual pushing. Nine male and eight female participants performed isometric exertions at two reach distances (0 and elbow-grip) and six different positions of the hand interface (handle), defined by the plane (longitudinal, lateral, horizontal) and orientation (0 degrees and 45 degrees). Electrogoniometer instruments were used to measure the displacements/postures of the wrist and elbow joints and the forearm, and force measuring strain gauges were used to measure the exerted hand forces (x-, y- and z-components). The results showed that ability to vary arm posture, particularly the forearm, is important during build up of force and that people tend to seek for a balance in the forces applied at the hands by exerting more in the vertical direction. Also, lateral plane handle positions permitted exertion of greater forces than longitudinal and horizontal plane positions.

Reticulate Acropigmentation of Dohi: A Case Report with Insight into Genodermatoses with Mottled Pigmentation

PubMed Central

Mohana, Deepak; Verma, Ujjwala; Amar, Amarkant Jha; Choudhary, R K P

2012-01-01

Reticulate acropigmentation of Dohi also called dyschromatosis symmetrica hereditaria or symmetrical dyschromatosis of the extremities is an autosomal dominant inherited disorder. It is characterized by mottled pigmentation with patchy depigmentation commonly over the back of the hands and feet and sometimes on the arms and legs PMID:22470208

Effect of a mixed reality-based intervention on arm, hand, and finger function on chronic stroke.

PubMed

Colomer, Carolina; Llorens, Roberto; Noé, Enrique; Alcañiz, Mariano

2016-05-11

Virtual and mixed reality systems have been suggested to promote motor recovery after stroke. Basing on the existing evidence on motor learning, we have developed a portable and low-cost mixed reality tabletop system that transforms a conventional table in a virtual environment for upper limb rehabilitation. The system allows intensive and customized training of a wide range of arm, hand, and finger movements and enables interaction with tangible objects, while providing audiovisual feedback of the participants' performance in gamified tasks. This study evaluates the clinical effectiveness and the acceptance of an experimental intervention with the system in chronic stroke survivors. Thirty individuals with stroke were included in a reversal (A-B-A) study. Phase A consisted of 30 sessions of conventional physical therapy. Phase B consisted of 30 training sessions with the experimental system. Both interventions involved flexion and extension of the elbow, wrist, and fingers, and grasping of different objects. Sessions were 45-min long and were administered three to five days a week. The body structures (Modified Ashworth Scale), functions (Motricity Index, Fugl-Meyer Assessment Scale), activities (Manual Function Test, Wolf Motor Function Test, Box and Blocks Test, Nine Hole Peg Test), and participation (Motor Activity Log) were assessed before and after each phase. Acceptance of the system was also assessed after phase B (System Usability Scale, Intrinsic Motivation Inventory). Significant improvement was detected after the intervention with the system in the activity, both in arm function measured by the Wolf Motor Function Test (p < 0.01) and finger dexterity measured by the Box and Blocks Test (p < 0.01) and the Nine Hole Peg Test (p < 0.01); and participation (p < 0.01), which was maintained to the end of the study. The experimental system was reported as highly usable, enjoyable, and motivating. Our results support the clinical effectiveness

Adapting proportional myoelectric-controlled interfaces for prosthetic hands.

PubMed

Pistohl, Tobias; Cipriani, Christian; Jackson, Andrew; Nazarpour, Kianoush

2013-01-01

Powered hand prostheses with many degrees of freedom are moving from research into the market for prosthetics. In order to make use of the prostheses' full functionality, it is essential to find efficient ways to control their multiple actuators. Human subjects can rapidly learn to employ electromyographic (EMG) activity of several hand and arm muscles to control the position of a cursor on a computer screen, even if the muscle-cursor map contradicts directions in which the muscles would act naturally. We investigated whether a similar control scheme, using signals from four hand muscles, could be adopted for real-time operation of a dexterous robotic hand. Despite different mapping strategies, learning to control the robotic hand over time was surprisingly similar to the learning of two-dimensional cursor control.

Effects of task-oriented robot training on arm function, activity, and quality of life in chronic stroke patients: a randomized controlled trial.

PubMed

Timmermans, Annick A A; Lemmens, Ryanne J M; Monfrance, Maurice; Geers, Richard P J; Bakx, Wilbert; Smeets, Rob J E M; Seelen, Henk A M

2014-03-31

Over fifty percent of stroke patients experience chronic arm hand performance problems, compromising independence in daily life activities and quality of life. Task-oriented training may improve arm hand performance after stroke, whereby augmented therapy may lead to a better treatment outcome. Technology-supported training holds opportunities for increasing training intensity. However, the effects of robot-supported task-oriented training with real life objects in stroke patients are not known to date. The aim of the present study was to investigate the effectiveness and added value of the Haptic Master robot combined with task-oriented arm hand training in chronic stroke patients. In a single-blind randomized controlled trial, 22 chronic stroke patients were randomly allocated to receive either task-oriented robot-assisted arm-hand training (experimental group) or task-oriented non-robotic arm-hand training (control group). For training, the T-TOAT (Technology-supported Task-Oriented Arm Training) method was applied. Training was provided during 8 weeks, 4 times/week, 2 × 30 min/day. A significant improvement after training on the Action Research Arm Test (ARAT) was demonstrated in the experimental group (p = 0.008). Results were maintained until 6 months after cessation of the training. On the perceived performance measure (Motor Activity Log (MAL)), both, the experimental and control group improved significantly after training (control group p = 0.008; experimental group p = 0.013). The improvements on MAL in both groups were maintained until 6 months after cessation of the training. With regard to quality of life, only in the control group a significant improvement after training was found (EuroQol-5D p = 0.015, SF-36 physical p = 0.01). However, the improvement on SF-36 in the control group was not maintained (p = 0.012). No between-group differences could be demonstrated on any of the outcome measures. Arm hand performance improved in chronic stroke

Adapting a Robot Hand to Specialized Functions

NASA Technical Reports Server (NTRS)

Clark, Keith H.

1987-01-01

Adaptor enables mechanical and electrical connections made easily between special-purpose end effector and arm of robot or remote mainpulator. Use in prosthetic devices also contemplatd. With adaptor, hand changed quickly from device designed to grasp objects of various sizes and shapes to device intended to do specific task efficiently.

A patient with an electrical burn treated by modified bilateral hemipelvectomy and disarticulation of the right arm.

PubMed

Still, J M; Law, E; Friedman, B; Gates, C E

2001-01-01

A 23-year-old Hispanic worker sustained an electrical injury to 45% of his body when a crane hit a power line. Amputations of both legs, with bilateral partial hemipelvectomies, were required. A disarticulation of the right arm at the shoulder was also preformed. Resection of necrotic bowel, debridement of 95% of the abdominal wall, and resection of the genitalia was eventually required, with later reconstruction of the abdominal wall. After wound healing was complete, the patient was fitted with Jobst garments. A customized bucket prosthesis with a temperature control, to allow sitting upright, was provided. An electric wheel chair and a myoelectronic prosthetic arm were supplied. Rehabilitation was begun early.

Sensory-Feedback Exoskeletal Arm Controller

NASA Technical Reports Server (NTRS)

An, Bin; Massie, Thomas H.; Vayner, Vladimir

2004-01-01

between the exoskeletal mechanism and the shoulder. 4. The fourth DOF is that of flexion and extension of the elbow. The reflected torque for this DOF is provided by motor 4 and drum 4, which are mounted on a bracket that can slide longitudinally by a pin-and-slot engagement with the upper-arm cuff to compensate for slight variations in the position of the kinematic center of the elbow. Attached to drum 4 is an adapter plate to which is attached a CRCM for the lower arm. 5. The lower-arm CRCM implements the fifth DOF, which is the twist of the forearm about its longitudinal axis. Motor 5 provides the reflected torque for this DOF by driving the lower-arm cuff. A rod transmits twist and torsion between the lower-arm cuff and the hand cuff. With this system, the motion of the wearer s joints and the reflected torques applied to these joints can be measured and controlled in a relatively simple manner. This is because the anthropomorphic design of the mechanism imitates the kinematics of the human arm, eliminating the need for kinematic conversion of joint-torque and joint-angle data.

Hand involvement in children with Charcot-Marie-Tooth disease type 1A.

PubMed

Burns, Joshua; Bray, Paula; Cross, Lauren A; North, Kathryn N; Ryan, Monique M; Ouvrier, Robert A

2008-12-01

Charcot-Marie-Tooth disease type 1A (CMT1A), a demyelinating neuropathy characterised by progressive length-dependent muscle weakness and atrophy, is thought to affect the foot and leg first followed some time later by hand weakness and dysfunction. We aimed to characterise hand strength, function and disease-related symptoms in children with CMT1A. Intrinsic and extrinsic hand strength was measured by hand-held dynamometry, function by nine-hole peg test, and disease-related symptoms by interview and examination in 84 affected children aged 2-16 years. Hand weakness and dysfunction was present from the earliest stages of the disease. While hand strength and function measures tended to increase with age throughout childhood, at no point did they reach normal values. Day-to-day hand problems such as poor handwriting, weakness, pain and sensory symptoms also worsened with age. The hand is affected at all ages in children with CMT1A, but may be under-recognised in its early stages, potentially delaying therapy.

Illusory sense of human touch from a warm and soft artificial hand.

PubMed

Cabibihan, John-John; Joshi, Deepak; Srinivasa, Yeshwin Mysore; Chan, Mark Aaron; Muruganantham, Arrchana

2015-05-01

To touch and be touched are vital to human development, well-being, and relationships. However, to those who have lost their arms and hands due to accident or war, touching becomes a serious concern that often leads to psychosocial issues and social stigma. In this paper, we demonstrate that the touch from a warm and soft rubber hand can be perceived by another person as if the touch were coming from a human hand. We describe a three-step process toward this goal. First, we made participants select artificial skin samples according to their preferred warmth and softness characteristics. At room temperature, the preferred warmth was found to be 28.4 °C at the skin surface of a soft silicone rubber material that has a Shore durometer value of 30 at the OO scale. Second, we developed a process to create a rubber hand replica of a human hand. To compare the skin softness of a human hand and artificial hands, a robotic indenter was employed to produce a softness map by recording the displacement data when constant indentation force of 1 N was applied to 780 data points on the palmar side of the hand. Results showed that an artificial hand with skeletal structure is as soft as a human hand. Lastly, the participants' arms were touched with human and artificial hands, but they were prevented from seeing the hand that touched them. Receiver operating characteristic curve analysis suggests that a warm and soft artificial hand can create an illusion that the touch is from a human hand. These findings open the possibilities for prosthetic and robotic hands that are life-like and are more socially acceptable.

Human-arm-and-hand-dynamic model with variability analyses for a stylus-based haptic interface.

PubMed

Fu, Michael J; Cavuşoğlu, M Cenk

2012-12-01

Haptic interface research benefits from accurate human arm models for control and system design. The literature contains many human arm dynamic models but lacks detailed variability analyses. Without accurate measurements, variability is modeled in a very conservative manner, leading to less than optimal controller and system designs. This paper not only presents models for human arm dynamics but also develops inter- and intrasubject variability models for a stylus-based haptic device. Data from 15 human subjects (nine male, six female, ages 20-32) were collected using a Phantom Premium 1.5a haptic device for system identification. In this paper, grip-force-dependent models were identified for 1-3-N grip forces in the three spatial axes. Also, variability due to human subjects and grip-force variation were modeled as both structured and unstructured uncertainties. For both forms of variability, the maximum variation, 95 %, and 67 % confidence interval limits were examined. All models were in the frequency domain with force as input and position as output. The identified models enable precise controllers targeted to a subset of possible human operator dynamics.

Profiles of muscularity in junior Olympic weight lifters.

PubMed

Kanehisa, H; Funato, K; Abe, T; Fukunaga, T

2005-03-01

This study aimed to investigate the muscularity of strength-trained junior athletes. Muscle thickness (Mt) values at 10 sites (anterior forearm, anterior upper arm, posterior upper arm, chest, abdomen, back, anterior thigh, posterior thigh, anterior lower leg, and posterior lower leg) were determined in junior Olympic weight lifters (OWL, n=7, 15.1+/-0.3 y, mean+/-SD) and non-athletes (CON, n=13, 15.1+/-0.3 y) using a brightness mode ultrasonography. Skeletal age assessed with the Tanner-Whitehouse II method (20 hand-wrist bones) was similar in OWL (16.4+/-0.7 y) and CON (16.3+/-0.6 y). At the 6 sites (anterior forearm, anterior upper arm, posterior upper arm, chest, back and anterior thigh), OWL showed significantly greater Mt values than CON even in terms of Mt relative to body mass(1/3) Mt x BM(-1/3). On the other hand, there were no significant differences between the 2 groups in the Mt ratios of the anterior to posterior site in the upper arm, thigh and lower leg and those of the back to either the chest or abdomen in the trunk. For OWL only, skeletal age was significantly correlated to Mt x BM(-1/3) at the abdomen (r=0.869, p<0.05) and anterior thigh (r=0.883, p<0.05). The findings here indicate that 1) as compared to adolescent non-athletes, junior Olympic weight lifters show a greater muscularity in the upper body and anterior thigh without predominant development in either of anterior and posterior sites within the same body segment, 2) for junior Olympic weight lifters, the muscularity of abdominal and knee extensor muscles is influenced by the biological maturation.

A hybrid BMI-based exoskeleton for paresis: EMG control for assisting arm movements

NASA Astrophysics Data System (ADS)

Kawase, Toshihiro; Sakurada, Takeshi; Koike, Yasuharu; Kansaku, Kenji

2017-02-01

Objective. Brain-machine interface (BMI) technologies have succeeded in controlling robotic exoskeletons, enabling some paralyzed people to control their own arms and hands. We have developed an exoskeleton asynchronously controlled by EEG signals. In this study, to enable real-time control of the exoskeleton for paresis, we developed a hybrid system with EEG and EMG signals, and the EMG signals were used to estimate its joint angles. Approach. Eleven able-bodied subjects and two patients with upper cervical spinal cord injuries (SCIs) performed hand and arm movements, and the angles of the metacarpophalangeal (MP) joint of the index finger, wrist, and elbow were estimated from EMG signals using a formula that we derived to calculate joint angles from EMG signals, based on a musculoskeletal model. The formula was exploited to control the elbow of the exoskeleton after automatic adjustments. Four able-bodied subjects and a patient with upper cervical SCI wore an exoskeleton controlled using EMG signals and were required to perform hand and arm movements to carry and release a ball. Main results. Estimated angles of the MP joints of index fingers, wrists, and elbows were correlated well with the measured angles in 11 able-bodied subjects (correlation coefficients were 0.81  ±  0.09, 0.85  ±  0.09, and 0.76  ±  0.13, respectively) and the patients (e.g. 0.91  ±  0.01 in the elbow of a patient). Four able-bodied subjects successfully positioned their arms to adequate angles by extending their elbows and a joint of the exoskeleton, with root-mean-square errors  <6°. An upper cervical SCI patient, empowered by the exoskeleton, successfully carried a ball to a goal in all 10 trials. Significance. A BMI-based exoskeleton for paralyzed arms and hands using real-time control was realized by designing a new method to estimate joint angles based on EMG signals, and these may be useful for practical rehabilitation and the support of

A hybrid BMI-based exoskeleton for paresis: EMG control for assisting arm movements.

PubMed

Kawase, Toshihiro; Sakurada, Takeshi; Koike, Yasuharu; Kansaku, Kenji

2017-02-01

Brain-machine interface (BMI) technologies have succeeded in controlling robotic exoskeletons, enabling some paralyzed people to control their own arms and hands. We have developed an exoskeleton asynchronously controlled by EEG signals. In this study, to enable real-time control of the exoskeleton for paresis, we developed a hybrid system with EEG and EMG signals, and the EMG signals were used to estimate its joint angles. Eleven able-bodied subjects and two patients with upper cervical spinal cord injuries (SCIs) performed hand and arm movements, and the angles of the metacarpophalangeal (MP) joint of the index finger, wrist, and elbow were estimated from EMG signals using a formula that we derived to calculate joint angles from EMG signals, based on a musculoskeletal model. The formula was exploited to control the elbow of the exoskeleton after automatic adjustments. Four able-bodied subjects and a patient with upper cervical SCI wore an exoskeleton controlled using EMG signals and were required to perform hand and arm movements to carry and release a ball. Estimated angles of the MP joints of index fingers, wrists, and elbows were correlated well with the measured angles in 11 able-bodied subjects (correlation coefficients were 0.81  ±  0.09, 0.85  ±  0.09, and 0.76  ±  0.13, respectively) and the patients (e.g. 0.91  ±  0.01 in the elbow of a patient). Four able-bodied subjects successfully positioned their arms to adequate angles by extending their elbows and a joint of the exoskeleton, with root-mean-square errors  <6°. An upper cervical SCI patient, empowered by the exoskeleton, successfully carried a ball to a goal in all 10 trials. A BMI-based exoskeleton for paralyzed arms and hands using real-time control was realized by designing a new method to estimate joint angles based on EMG signals, and these may be useful for practical rehabilitation and the support of daily actions.

Increased knee valgus alignment and moment during single-leg landing after overhead stroke as a potential risk factor of anterior cruciate ligament injury in badminton.

PubMed

Kimura, Yuka; Ishibashi, Yasuyuki; Tsuda, Eiichi; Yamamoto, Yuji; Hayashi, Yoshimitsu; Sato, Shuichi

2012-03-01

In badminton, knees opposite to the racket-hand side received anterior cruciate ligament (ACL) injuries during single-leg landing after overhead stroke. Most of them occurred in the backhand-side of the rear court. Comparing lower limb biomechanics during single-leg landing after overhead stroke between the forehand-side and backhand-side court may help explain the different injury rates depending on court position. The knee kinematics and kinetics during single-leg landing after overhead stroke following back-stepping were different between the forehand-side and backhand-side court. Controlled laboratory study. Hip, knee and ankle joint kinematic and knee kinetic data were collected for 17 right-handed female college badminton players using a 3-dimensional motion analysis system. Subjects performed single-left-legged landing after an overhead stroke following left and right back-stepping. The kinematic and kinetic data of the left lower extremities during landing were measured and compared between left and right back-steps. Hip flexion and abduction and knee valgus at the initial contact, hip and knee flexion and knee valgus at the maximum knee flexion and the maximum knee valgus moment were significantly larger for the left back-step than the right back-step (p<0.05). Significant differences in joint kinematics and kinetics of the lower extremity during single-leg landing after overhead stroke were observed between different back-step directions. Increased knee valgus angle and moment following back-stepping to the backhand-side might be related to the higher incidence of ACL injury during single-leg landing after overhead stroke.

Restless legs syndrome.

PubMed

Ekbom, Karl; Ulfberg, J

2009-11-01

Restless legs syndrome (RLS) is a common neurological sensory-motor disorder that is characterized by intense restlessness and unpleasant creeping sensations deep inside the lower legs. Symptoms appear when the legs are at rest and are worst in the evening and at night. They force patients to keep moving their legs, and often to get out of bed and wander about. Periodic limb movements (PLMS) are also common during sleep amongst those suffering from RLS, and sleep efficiency is severely reduced. There are idiopathic as well as symptomatic forms of RLS, the latter being associated with e.g. pregnancy, iron deficiency and chronic renal failure. A family history of RLS is very common and pedigrees in these cases suggest an autosomal-dominant transmission with high penetrance. Genetic investigations have been performed in order to identify genes associated with RLS. Several loci have been found (on chromosomes 12q, 14q, 9p, 2q, 20p and 16p). Pathophysiology of RLS remains incompletely understood. However, advanced brain imaging studies and positive results of dopaminergic treatment suggest that RLS may be generated by dopamine dysfunction locally within the central nervous system. At present, there is a wide range of treatment options including levodopa, dopamine agonists, opioids, benzodiazepines, antiepileptic drugs and iron supplements.

Design of a Lightweight Soft Robotic Arm Using Pneumatic Artificial Muscles and Inflatable Sleeves.

PubMed

Ohta, Preston; Valle, Luis; King, Jonathan; Low, Kevin; Yi, Jaehyun; Atkeson, Christopher G; Park, Yong-Lae

2018-04-01

As robots begin to interact with humans and operate in human environments, safety becomes a major concern. Conventional robots, although reliable and consistent, can cause injury to anyone within its range of motion. Soft robotics, wherein systems are made to be soft and mechanically compliant, are thus a promising alternative due to their lightweight nature and ability to cushion impacts, but current designs often sacrifice accuracy and usefulness for safety. We, therefore, have developed a bioinspired robotic arm combining elements of rigid and soft robotics such that it exhibits the positive qualities of both, namely compliance and accuracy, while maintaining a low weight. This article describes the design of a robotic arm-wrist-hand system with seven degrees of freedom (DOFs). The shoulder and elbow each has two DOFs for two perpendicular rotational motions on each joint, and the hand has two DOFs for wrist rotations and one DOF for a grasp motion. The arm is pneumatically powered using custom-built McKibben type pneumatic artificial muscles, which are inflated and deflated using binary and proportional valves. The wrist and hand motions are actuated through servomotors. In addition to the actuators, the arm is equipped with a potentiometer in each joint for detecting joint angle changes. Simulation and experimental results for closed-loop position control are also presented in the article.

Validation of the Kohnen Restless Legs Syndrome-Quality of Life instrument.

PubMed

Kohnen, Ralf; Martinez-Martin, Pablo; Benes, Heike; Trenkwalder, Claudia; Högl, Birgit; Dunkl, Elmar; Walters, Arthur S

2016-08-01

Due to the symptoms and the sleep disturbances it causes, Restless Legs Syndrome (RLS) has a negative impact on quality of life. Measurement of such impact can be performed by means of questionnaires, such as the Kohnen Restless Legs Syndrome-Quality of Life questionnaire (KRLS-QoL), a specific 12-item instrument that is self-applied by patients. The present study is aimed at performing a first formal validation study of this instrument. Eight hundred ninety-one patients were included for analysis. RLS severity was assessed by the International Restless Legs Scale (IRLS), Restless Legs Syndrome-6 scales (RLS-6), and Clinical Global Impression of Severity. In addition the Epworth Sleepiness Scale (ESS) was assessed. Acceptability, dimensionality, scaling assumptions, reliability, precision, hypotheses-related validity, and responsiveness were tested. There were missing data in 3.58% patients. Floor and ceiling effects were low for the subscales, global evaluation, and summary index derived from items 1 to 11 after checking that scaling assumptions were met. Exploratory parallel factor analysis showed that the KRLS-QoL may be deemed unidimensional, ie, that all components of the scale are part of one overall general quality of life factor. Indexes of internal consistency (alpha = 0.88), item-total correlation (r S  = 0.32-0.71), item homogeneity coefficient (0.41), and scale stability (ICC = 0.73) demonstrated a satisfactory reliability of the KRLS-QoL. Moderate or high correlations were obtained between KRLS-QoL scores and the IRLS, some components of the RLS-6, inter-KRLS-QoL domains, and global evaluations. Known-groups validity for severity levels grouping and responsiveness analysis results were satisfactory, the latter showing higher magnitudes of response for treated than for placebo arms. The KRLS-QoL was proven an acceptable, reliable, valid, and responsive measure to assess the impact of the RLS on quality of life. Copyright © 2016 The Authors

The Motor and the Brake of the Trailing Leg in Human Walking: Leg Force Control Through Ankle Modulation and Knee Covariance

PubMed Central

Toney, Megan E.; Chang, Young-Hui

2016-01-01

Human walking is a complex task, and we lack a complete understanding of how the neuromuscular system organizes its numerous muscles and joints to achieve consistent and efficient walking mechanics. Focused control of select influential task-level variables may simplify the higher-level control of steady state walking and reduce demand on the neuromuscular system. As trailing leg power generation and force application can affect the mechanical efficiency of step-to-step transitions, we investigated how joint torques are organized to control leg force and leg power during human walking. We tested whether timing of trailing leg force control corresponded with timing of peak leg power generation. We also applied a modified uncontrolled manifold analysis to test whether individual or coordinated joint torque strategies most contributed to leg force control. We found that leg force magnitude was adjusted from step-to-step to maintain consistent leg power generation. Leg force modulation was primarily determined by adjustments in the timing of peak ankle plantar-flexion torque, while knee torque was simultaneously covaried to dampen the effect of ankle torque on leg force. We propose a coordinated joint torque control strategy in which the trailing leg ankle acts as a motor to drive leg power production while trailing leg knee torque acts as a brake to refine leg power production. PMID:27334888

Quantitative Tester And Reconditioner For Hand And Arm

NASA Technical Reports Server (NTRS)

Engle, Gary; Bond, Malcolm; Naumann, Theodore

1993-01-01

Apparatus measures torques, forces, and motions of hand, wrist, forearm, elbow, and shoulder and aids in reconditioning muscles involved. Used to determine strengths and endurances of muscles, ranges of motion of joints, and reaction times. Provides quantitative data used to assess extent to which disuse, disease, or injury causes deterioration of muscles and of motor-coordination skills. Same apparatus serves as exercise machine to restore muscle performance by imposing electronically controlled, gradually increasing loads on muscles. Suitable for training and evaluating astronauts, field testing for workers' compensation claims, and physical therapy in hospitals. With aid of various attachments, system adapted to measure such special motions as pinching, rotation of wrist, and supination and pronation of the forearm. Attachments are gloves, wristlets, and sleeves.

Cross-cultural adaptation of the Disability of Arm, Shoulder, and Hand questionnaire: Spanish for Puerto Rico Version

PubMed Central

Mulero-Portela, Ana L.; Colón-Santaella, Carmen L.; Cruz-Gomez, Cynthia

2010-01-01

The purpose of this study was to perform a cross-cultural adaptation of the Disability of Arm, Shoulder, and Hand (DASH) questionnaire to Spanish for Puerto Rico. Five steps were followed for the cross-cultural adaptation: forward translations into Spanish for Puerto Rico, synthesis of the translations, back translations into English, revision by an expert committee, and field test of the prefinal version. Psychometric characteristics of reliability and construct validity were evaluated for the final version. Internal consistency of the final version was high (Cronbach's α = 0.97) and item-to-total correlations were moderate (range from 0.44 to 0.85). Construct validity was evaluated by correlating the DASH with the scales of the Functional Assessment of Cancer Therapy - Breast. Fair to moderate correlations found in this study between the DASH and most scales of the Functional Assessment of Cancer Therapy - Breast support the construct validity of the Puerto Rico-Spanish DASH. The final version of the questionnaire was revised and approved by the Institute for Work and Health of Canada. Revisions to the original DASH English version are recommended. This version of the DASH is valid and reliable, and it can be used to evaluate outcomes in both clinical and research settings. PMID:19901616

The SOBANE strategy for the management of risk, as applied to whole-body or hand-arm vibration.

PubMed

Malchaire, J; Piette, A

2006-06-01

The objective was to develop a coherent set of methods to be used effectively in industry to prevent and manage the risks associated with exposure to vibration, by coordinating the progressive intervention of the workers, their management, the occupational health and safety (OHS) professionals and the experts. The methods were developed separately for the exposure to whole-body and hand-arm vibration. The SOBANE strategy of risk prevention includes four levels of intervention: level 1, Screening; level 2, Observation; level 3, Analysis and; level 4, Expertise. The methods making it possible to apply this strategy were developed for 14 types of risk factors. The article presents the methods specific to the prevention of the risks associated with the exposure to vibration. The strategy is similar to those published for the risks associated with exposure to noise, heat and musculoskeletal disorders. It explicitly recognizes the qualifications of the workers and their management with regard to the work situation and shares the principle that measuring the exposure of the workers is not necessarily the first step in order to improve these situations. It attempts to optimize the recourse to the competences of the OHS professionals and the experts, in order to come more rapidly, effectively and economically to practical control measures.

Effective information campaign for management of exposure to hand-arm vibration in the metal and construction industries.

PubMed

Sauni, Riitta; Toivio, Pauliina; Esko, Toppila; Pääkkönen, Rauno; Uitti, Jukka

2015-01-01

European Directive 2002/44/EC defines employers' responsibilities in the risk management of hand-arm vibration (HAV). However, the directive is still not completely implemented in all risk industries. The aim of our study was to determine whether it is possible to improve the recognition and management of the risks of HAV at workplaces with a one-year information campaign. A questionnaire on opinions and measures for controlling HAV exposure at workplaces was sent to all occupational safety representatives and occupational safety managers in the construction and metal industry in Finland (n=1887) and once again to those who responded to the first questionnaire (n=961) one year after the campaign. The campaign increased recognition of HAV in risk assessment from 57.0% to 68.3% (p=.001), increased measures to decrease exposure to HAV from 54.6% to 64.2% (p=.006) and increased the number of programmes to control the risks due to HAV (p<.001). The information campaign, which focuses on the construction and metal industries, proved to be effective in increasing the awareness of the risks of HAV and the measures needed to control exposure to HAV. A similar campaign can be recommended in the case of risks specific to certain occupations.

29 CFR 500.105 - DOT standards adopted by the Secretary.

Code of Federal Regulations, 2014 CFR

2014-07-01

... person possesses the following minimum qualifications: (A) No loss of foot, leg, hand or arm, (B) No mental, nervous, organic, or functional disease, likely to interfere with safe driving. (C) No loss of... loading—(A) Distribution and securing of load. No motor vehicle shall be driven nor shall any motor...

Comparison of thermoregulatory responses to heat between Malaysian and Japanese males during leg immersion.

PubMed

Wijayanto, Titis; Wakabayashi, Hitoshi; Lee, Joo-Young; Hashiguchi, Nobuko; Saat, Mohamed; Tochihara, Yutaka

2011-07-01

The objective of this study was to investigate thermoregulatory responses to heat in tropical (Malaysian) and temperate (Japanese) natives, during 60 min of passive heating. Ten Japanese (mean ages: 20.8 ± 0.9 years) and ten Malaysian males (mean ages: 22.3 ± 1.6 years) with matched morphological characteristics and physical fitness participated in this study. Passive heating was induced through leg immersion in hot water (42°C) for 60 min under conditions of 28°C air temperature and 50% RH. Local sweat rate on the forehead and thigh were significantly lower in Malaysians during leg immersion, but no significant differences in total sweat rate were observed between Malaysians (86.3 ± 11.8 g m(-2) h(-1)) and Japanese (83.2 ± 6.4 g m(-2) h(-1)) after leg immersion. In addition, Malaysians displayed a smaller rise in rectal temperature (0.3 ± 0.1°C) than Japanese (0.7 ± 0.1°C) during leg immersion, with a greater increase in hand skin temperature. Skin blood flow was significantly lower on the forehead and forearm in Malaysians during leg immersion. No significant different in mean skin temperature during leg immersion was observed between the two groups. These findings indicated that regional differences in body sweating distribution might exist between Malaysians and Japanese during heat exposure, with more uniform distribution of local sweat rate over the whole body among tropical Malaysians. Altogether, Malaysians appear to display enhanced efficiency of thermal sweating and thermoregulatory responses in dissipating heat loss during heat loading. Thermoregulatory differences between tropical and temperate natives in this study can be interpreted as a result of heat adaptations to physiological function.

Prosthetic Hand For Holding Rods, Tools, And Handles

NASA Technical Reports Server (NTRS)

Belcher, Jewell G., Jr.; Vest, Thomas W.

1995-01-01

Prosthetic hand with quick-grip/quick-release lever broadens range of specialized functions available to lower-arm amputee by providing improved capabilities for gripping rods, tools, handles, and like. Includes two stationary lower fingers opposed by one pivoting upper finger. Lever operates in conjunction with attached bracket.

A colored leg banding technique for Amazona parrots

USGS Publications Warehouse

Meyers, J.M.

1995-01-01

A technique for individual identification of Amazona was developed using plastic leg bands. Bands were made from 5- and 7-mm-wide strips of laminated PVC coiled 2.5 times with an inside diameter 4-5 mm gt the maximum diameter of the parrot's leg. Seventeen parrots were captured in Puerto Rico, marked with individual plastic leg bands, and observed for 204-658 d with only one lost or damaged plastic band. Plastic leg bands did not cause injury to or calluses on parrots' legs. The plastic material used for making leg bands was available in 18 colors in 1994, which would allow unique marking of 306 individuals using one plastic leg band on each leg.

Foot, leg, and ankle swelling

MedlinePlus

... feet - legs; Ankle swelling; Foot swelling; Leg swelling; Edema - peripheral; Peripheral edema ... 31. Trayes KP, Studdiford JS, Pickle S, Tully AS. Edema: diagnosis and management. Am Fam Physician . 2013;88( ...

Pipe crawler with extendable legs

DOEpatents

Zollinger, William T.

1992-01-01

A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler.

Pipe crawler with extendable legs

DOEpatents

Zollinger, W.T.

1992-06-16

A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long as a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler. 8 figs.

Pipe crawler with extendable legs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zollinger, W.T.

1992-06-16

A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long as a leg assembly is wide and the crawler can crawlmore » through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler. 8 figs.« less

Restless legs syndrome mimicking S1 radiculopathy.

PubMed

Zambelis, Th; Wolgamuth, B R; Papoutsi, S N; Economou, N T

2016-01-01

Α case of a chronic idiopathic form of a severe type of Restless Legs Syndrome (RLS), which developed during pregnancy and persisted after this, misdiagnosed for 34 years as radiculopathy S1, is reported. In spite of the thorough clinical and laboratory investigation, in addition to constant changes of the therapeutic approach, the diagnosis of S1 radiculopathy could not be confirmed, resulting in a chronic clinical course; the latter was characterized by relapses and remissions not attributed or linked in any way to the treatment (various types of). In fact, it was due to a routine workup in a sleep clinic, where the patient was referred because of a coincident chronic insomnia (Restless Legs Syndrome is a known and important cause of insomnia/chronic insomnia), which resulted in a proper diagnosis and treatment of this case. With the use of Restless Legs Syndrome appropriate treatment (Pramipexole 0.18 mg taken at bedtime, a dopaminergic agent and Level A recommended drug for Restless Legs Syndrome) an excellent response and immediate elimination of symptoms was achieved. Restless Legs Syndrome may present with a variety of symptoms (with the most prominent shortly being reported with the acronym URGE: Urge to move the legs usually associated with unpleasant leg sensations, Rest induces symptoms, Getting active brings relief, Evening and night deteriorate symptoms); given the fact that Restless Legs Syndrome presents with a great variety and heterogeneity of symptoms (mostly pain, dysesthesia and paresthesia), which may occur in several other diseases (the so called "RLS mimics"), proper diagnosis of Restless Legs Syndrome usually fails. Restless Legs Syndrome misinterpreted as S1 radiculopathy, to the best of our knowledge, has not been reported yet in the literature. Here, case history, clinical course and common RLS mimics are presented. Different forms of Restless Legs Syndrome manifestations, which are commonly -as in this case- misinterpreted due to their

Incorporation of the fluoroless C-Arm Trainer at the American Urological Association hands on training percutaneous renal access.

PubMed

Noureldin, Yasser A; Hoenig, David M; Zhao, Philip; Elsamra, Sammy E; Stern, Joshua; Gaunay, Geoffrey; Motamedinia, Piruz; Okeke, Zeph; Rastinehad, Ardeshir R; Sweet, Robert M

2018-07-01

To assess for usefulness and validity evidence for incorporating the C-Arm Trainer (CAT) simulator into the annual AUA hands on course for training percutaneous nephrolithotomy (PCNL). The course started with a didactic session followed by four stations for training the "bull's eye" technique using the CAT simulator. Each station included a pre-test, 30-min practice on the simulator, and post-test. All participants were assessed using a 4-item checklist. All participants were asked to fill in a qualitative self-assessment questionnaire after the pre- and the post-test, and respond to a course evaluation questionnaire and post-course survey. A total of 38 physicians, who attended the hands on course, voluntarily participated in the study. Only 21.1% had previous practice on PCNL simulators. Compared with the results of the checklist total score and the qualitative self-assessment questionnaire scores after the pre-test, there was significant improvement in the checklist total score (p < 0.001), temporal demands (p = 0.003), situational stress (p = 0.003, and performance (0.003) after the post-test. A total of 14 (36%) participants responded to the course evaluation questionnaire, 50% evaluated the course as excellent, 28.6% as very good, and 21.4% as good. Unfortunately, only five (13%) participants responded to the post-course survey, 4/5 implemented the new competencies and knowledge into their practice, and 3/5 have attempted to obtain fluoroscopic guided PCA without assistance. The CAT simulator was considered useful for training the percutaneous renal access procedure. There was significant improvement in the qualitative and quantitative assessment parameters after the post-test compared with the pre-test.

Microcephaly/lymphedema and terminal deletion of the long arm of chromosome 13

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fryns, J.P.

1995-07-03

Recently, we examined a 2-year-old boy with the association of microcephaly and significant pedal edema that extended to the distal parts of the legs. Prometaphase chromosome studies showed a small terminal deletion in the long arm of chromosome 13 of band 13q34, karyotype 46,XY,del(13)(q34{yields}qter). The present finding of a small terminal 13q34 deletion in this young boy with microcephaly/lymphedema is a first indication that the lymphedema/microcephaly association can be due to a small terminal 13q deletion. 2 refs.

Postoperative hand therapy in Dupuytren's disease.

PubMed

Herweijer, Hester; Dijkstra, Pieter U; Nicolai, Jean-Philippe A; Van der Sluis, Corry K

2007-11-30

Postoperative hand therapy in patients after surgery for Dupuytren's contracture is common medical practice to improve outcomes. Until now, patients are referred for postoperative hand rehabilitation on an empirical basis. To evaluate whether referral criteria after surgery because of Dupuytren's disease were actually adhered to, and, to analyse differences in outcomes between patients who were referred according to the criteria (correctly referred) and those who were not referred but should have been (incorrectly not referred). Referral pattern was evaluated prospectively in 46 patients. Total active/passive range of joint motion (TAM/ TPM), sensibility, pinch force, Disability Arm Shoulder Hand questionnaire (DASH) and Michigan Hand outcomes Questionnaire (MHQ) were used as outcome measures preoperatively and 10 months postoperatively. In total 21 patients were referred correctly and 17 patients were incorrectly not referred. Significant improvements on TAM/TPM, DASH and MHQ were found at follow-up for the total group. No differences in outcomes were found between patients correctly referred and patients incorrectly not referred for postoperative hand therapy. Referral criteria were not adhered to. Given the lack of differences in outcomes between patients correctly referred and patients incorrectly not referred, postoperative hand therapy in Dupuytren's disease should be reconsidered.

The Benslimane's Artistic Model for Leg Beauty.

PubMed

Benslimane, Fahd

2012-08-01

In 2000, the author started observing legs considered to be attractive. The goal was to have an ideal aesthetic model and compare the disparity between this model and a patient's reality. This could prove helpful during leg sculpturing to get closer to this ideal. Postoperatively, the result could then be compared to the ideal curves of the model legs and any remaining deviations from the ideal curves could be pointed out and eventually corrected in a second session. The lack of anthropometric studies of legs from the knee to the ankle led the author to select and study attractive legs to find out the common denominators of their beauty. The study consisted in analyzing the features that make legs look attractive. The legs of models in magazines were scanned and inserted into a PowerPoint program. The legs of live models, Barbie dolls, and athletes were photographed. Artistic drawings by Leonardo da Vinci were reviewed and Greek sculptures studied. Sculptures from the National Archaeological Museum of Athens were photographed and included in the PowerPoint program. This study shows that the first criterion for beautiful legs is the straightness of the leg column. Not a single attractive leg was found to deviate from the vertical, and each was in absolute continuity with the thigh. The second criterion is the similarity of curve distribution and progression from knee to ankle. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors at www.springer.com/00266.

Cross-cultural validation of the paediatric Gait, Arms, Legs, Spine (pGALS) tool for the screening of musculoskeletal disorders in Mexican children.

PubMed

Moreno-Torres, Luis Antonio; Hernández-Garduño, Adolfo Gabriel; Arellano-Valdés, Carmen Araceli; Salinas-Rodríguez, Aarón; Rubio-Perez, Nadina; Peláez-Ballestas, Ingris

2016-04-01

The aim of this study was to validate the paediatric Gait, Arms, Legs, Spine (pGALS) tool for Mexican Spanish to screen Mexican paediatric population for musculoskeletal (MSK) disorders. A cross-sectional study was performed in the Paediatric Hospital of the Mexican Social Security Institute in Guadalajara, Jalisco. The validation included children and adolescents aged 6-16 years, 87 patients with musculoskeletal disorders and 88 controls without musculoskeletal disorders. The cross-cultural validation followed the current published guidelines. The average pGALS administration time was 2.9 min (SD 0.54). The internal consistency score (Cronbach's α) was 0.90 (0.89 for inflammatory and 0.77 for non-inflammatory disorders) for MSK disorders, with a sensitivity of 97 % (95 % CI 92-99 %), a specificity of 93 % (95 % CI 86-97 %), a LR+ of 14.3, and a ROC curve of 0.95 (95 % CI 0.92-0.98 %). The inflammatory disorders group had a sensitivity of 97 % (95 % CI 86-99 %), a specificity of 93 % (95 % CI 86-97 %), a LR+ of 14.2, and a ROC curve of 0.95 % (95 % CI 0.91-0.99 %). The non-inflammatory disorders group had a sensitivity of 98 % (95 % CI 89-99 %), a specificity of 93 % (95 % CI 86-97 %), and a LR+ of 14.37, with a ROC curve of 0.95 % (95 % CI 0.92-0.98 %). pGALS is a valid screening tool, fast, easy to administer, and useful for detecting musculoskeletal disorders in Mexican children and adolescents.

On the Biomimetic Design of Agile-Robot Legs

PubMed Central

Garcia, Elena; Arevalo, Juan Carlos; Muñoz, Gustavo; Gonzalez-de-Santos, Pablo

2011-01-01

The development of functional legged robots has encountered its limits in human-made actuation technology. This paper describes research on the biomimetic design of legs for agile quadrupeds. A biomimetic leg concept that extracts key principles from horse legs which are responsible for the agile and powerful locomotion of these animals is presented. The proposed biomimetic leg model defines the effective leg length, leg kinematics, limb mass distribution, actuator power, and elastic energy recovery as determinants of agile locomotion, and values for these five key elements are given. The transfer of the extracted principles to technological instantiations is analyzed in detail, considering the availability of current materials, structures and actuators. A real leg prototype has been developed following the biomimetic leg concept proposed. The actuation system is based on the hybrid use of series elasticity and magneto-rheological dampers which provides variable compliance for natural motion. From the experimental evaluation of this prototype, conclusions on the current technological barriers to achieve real functional legged robots to walk dynamically in agile locomotion are presented. PMID:22247667

On the biomimetic design of agile-robot legs.

PubMed

Garcia, Elena; Arevalo, Juan Carlos; Muñoz, Gustavo; Gonzalez-de-Santos, Pablo

2011-01-01

The development of functional legged robots has encountered its limits in human-made actuation technology. This paper describes research on the biomimetic design of legs for agile quadrupeds. A biomimetic leg concept that extracts key principles from horse legs which are responsible for the agile and powerful locomotion of these animals is presented. The proposed biomimetic leg model defines the effective leg length, leg kinematics, limb mass distribution, actuator power, and elastic energy recovery as determinants of agile locomotion, and values for these five key elements are given. The transfer of the extracted principles to technological instantiations is analyzed in detail, considering the availability of current materials, structures and actuators. A real leg prototype has been developed following the biomimetic leg concept proposed. The actuation system is based on the hybrid use of series elasticity and magneto-rheological dampers which provides variable compliance for natural motion. From the experimental evaluation of this prototype, conclusions on the current technological barriers to achieve real functional legged robots to walk dynamically in agile locomotion are presented.

A laboratory breadboard system for dual-arm teleoperation

NASA Technical Reports Server (NTRS)

Bejczy, A. K.; Szakaly, Z.; Kim, W. S.

1990-01-01

The computing architecture of a novel dual-arm teleoperation system is described. The novelty of this system is that: (1) the master arm is not a replica of the slave arm; it is unspecific to any manipulator and can be used for the control of various robot arms with software modifications; and (2) the force feedback to the general purpose master arm is derived from force-torque sensor data originating from the slave hand. The computing architecture of this breadboard system is a fully synchronized pipeline with unique methods for data handling, communication and mathematical transformations. The computing system is modular, thus inherently extendable. The local control loops at both sites operate at 100 Hz rate, and the end-to-end bilateral (force-reflecting) control loop operates at 200 Hz rate, each loop without interpolation. This provides high-fidelity control. This end-to-end system elevates teleoperation to a new level of capabilities via the use of sensors, microprocessors, novel electronics, and real-time graphics displays. A description is given of a graphic simulation system connected to the dual-arm teleoperation breadboard system. High-fidelity graphic simulation of a telerobot (called Phantom Robot) is used for preview and predictive displays for planning and for real-time control under several seconds communication time delay conditions. High fidelity graphic simulation is obtained by using appropriate calibration techniques.

Maintained peak leg and pulmonary VO2 despite substantial reduction in muscle mitochondrial capacity.