Reducing Surgeon's Physical Stress in Minimally Invasive Neurosurgery

2019 ◽  
Vol 80 (05) ◽  
pp. 333-340
Author(s):  
Atsushi Nakayashiki ◽  
Tomohiro Kawaguchi ◽  
Atsuhiro Nakagawa ◽  
Fusako Mochizuki ◽  
Hiroaki Furukawa ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
Muscle Fatigue ◽  
Maximum Voluntary Contraction ◽  
Physical Stress ◽  
Voluntary Contraction ◽  
Minimally Invasive Neurosurgery ◽  
Hand Grip ◽  
Surgical Devices ◽  
Surgical Device ◽  
Round Section

Background and Study Aims Various minimally invasive approaches are used in neurosurgery. Surgeons must perform nondynamic fine movements in a narrow corridor, so specially designed surgical devices are essential. Unsophisticated instruments may pose potential hazards. The purpose of this study was to assess the factors associated with muscle fatigue during minimally invasive neurosurgery and to investigate whether physical stress can be reduced by refining the devices used. Material and Methods Four physical aspects of a handpiece were investigated: torque of conduits (0.20, 0.28, and 0.37 kgf*cm), shape of hand grip (five types), angle of the nozzle (0, 20, and 40 degrees), and weight balance (neutral, proximal, and distal). To evaluate muscle fatigue, surface electromyography was recorded from the extensor carpi radialis muscle and flexor carpi radialis muscle during a geometric tracing task. The maximum voluntary contraction (MVC) of each muscle and %MVC (muscle contraction during a task/MVC × 100) were used as the indexes of muscle fatigue. Results The shape of the hand grip significantly reduced %MVC, which is associated with muscle fatigue. The torque of conduits and angle of the nozzle tended to reduce muscle fatigue but not significantly. Weight balance did not affect muscle fatigue. Based on these results, we made two refined models: model α (torque of conduits 0.2 kgf*cm, angle of nozzle 20 degrees, neutral balance, hand grip with a 2.9 × 2.0-cm oval section with angled finger rest), and model β (torque of conduits 0.2 kgf*cm, angle of nozzle 20 degrees, neutral balance, hand grip with a 2.9-cm round section with a curved finger rest). The %MVC was significantly decreased with both types (p < 0.05 and p < 0.01, respectively), indicating reduction of muscle fatigue. Conclusions The geometrically refined surgical device can improve muscle load during surgery and reduce the surgeon's physical stress, thus minimizing the risk of complications.

Maintenance of Uncued Isometric Contractions by Blind and Sighted

1979 ◽  
Vol 49 (2) ◽  
pp. 475-479
Author(s):  
Claudia G. Emes
Keyword(s):  
Maximum Voluntary Contraction ◽  
Voluntary Contraction ◽  
Isometric Contractions ◽  
Hand Grip ◽  
Significant Difference ◽  
Static Contractions

A comparison of 10 blind and 10 sighted subjects to a proprioceptive task was examined by analysis of response to maintenance of uncued static contractions. In attempting to sustain hand-grip tensions at specified percentages of maximum voluntary contraction, blind and sighted groups showed no significant difference in performance.

scholarly journals Comparing neck extensor muscle function in asymptomatic Canadian adults and adults with tension-type headache: a cross-sectional study

BMJ Open ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. e020984 ◽  
Author(s):  
Andrée-Anne Marchand ◽  
Mariève Houle ◽  
Marie-Pier Girard ◽  
Marie-Ève Hébert ◽  
Martin Descarreaux
Keyword(s):  
Muscle Fatigue ◽  
Maximum Voluntary Contraction ◽  
Tension Type Headache ◽  
Voluntary Contraction ◽  
Extensor Muscle ◽  
Control Group ◽  
Physical Parameters ◽  
Cross Sectional ◽  
Neck Extension ◽  
Type Headache

AimTo further the understanding of the pathophysiological mechanisms underlying tension-type headache (TTH) by comparing the endurance and strength of neck extensor muscles under acute muscle fatigue in participants with TTH and asymptomatic participants.MethodsWe conducted a cross-sectional analysis of neck extensor muscle performance. Asymptomatic participants and participants with TTH were recruited via social media platforms and from the Université du Québec à Trois-Rivières community and employees. A total of 44 participants with TTH and 40 asymptomatic participants took part in an isometric neck extensor endurance task performed at 60% of their maximum voluntary contraction. Inclusion criteria for the headache group were to be older than 18 years old and to fulfil the International Headache Society classification’s criteria for either frequent episodic or chronic TTH. Clinical (self-efficacy, anxiety, neck disability and kinesiophobia) and physical parameters (neck extensors maximum voluntary contraction, endurance time, muscle fatigue) as well as characteristics of headache episodes (intensity, frequency and associated disability) were collected for all participants. Surface electromyography was used to document upper trapezius, splenius capitis and sternocleidomastoids muscle activity and muscle fatigue.ResultsBoth groups displayed similar neck extensor muscle endurance capacity with a mean difference of 6.2 s (p>0.05) in favour of the control group (control=68.1±32.3; TTH=61.9±20.1). Similarly, participants in the headache group showed comparable neck extensor muscle strength (95.9±30.4 N) to the control group (111.3±38.7 N). Among participants with TTH, those scoring as severely incapacitated by headaches were the ones with higher neck-related disability (F[1,44]=10.77; p=0.002), the more frequent headache episodes (F[1,44]=6.70; p=0.01) and higher maximum headache intensity (F[1,44]=10.81; p=0.002).ConclusionA fatigue task consisting of isometric neck extension cannot efficiently differentiate participants with TTH from asymptomatic participants.

scholarly journals Validation of a New Dynamic Muscle Fatigue Model and DMET Analysis

2016 ◽  
Vol 16 (1) ◽  
pp. 22-32
Author(s):  
Deep Seth ◽  
Damien Chablat ◽  
Fouad Bennis ◽  
Sophie Sakka ◽  
Marc Jubeau ◽  
...  
Keyword(s):  
Muscle Fatigue ◽  
Maximum Voluntary Contraction ◽  
Voluntary Contraction ◽  
Endurance Time ◽  
Absolute Value ◽  
Fatigue Model ◽  
Human Effort ◽  
Skeletal Disorder ◽  
Contraction Factor ◽  
Manual Tasks

Automation in industries reduced the human effort, but still there are many manual tasks in industries which lead to musculo-skeletal disorder (MSD). Muscle fatigue is one of the reasons leading to MSD. The objective of this article is to experimentally validate a new dynamic muscle fatigue model taking cocontraction factor into consideration using electromyography (EMG) and Maximum voluntary contraction (MVC) data. A new model (Seth's model) is developed by introducing a co-contraction factor 'n' in R. Ma's dynamic muscle fatigue model. The experimental data of ten subjects are used to analyze the muscle activities and muscle fatigue during extension-flexion motion of the arm on a constant absolute value of the external load. The findings for co-contraction factor shows that the fatigue increases when co-contraction index decreases. The dynamic muscle fatigue model is validated using the MVC data, fatigue rate and co-contraction factor of the subjects. It has been found that with the increase in muscle fatigue, co-contraction index decreases and 90% of the subjects followed the exponential function predicted by fatigue model. The model is compared with other models on the basis of dynamic maximum endurance time (DMET). The co-contraction has significant effect on the muscle fatigue model and DMET. With the introduction of co-contraction factor DMET decreases by 25:9% as compare to R. Ma's Model.

scholarly journals Computation and Evaluation of Features of Surface Electromyogram to Identify the Force of Muscle Contraction and Muscle Fatigue

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Sridhar P. Arjunan ◽  
Dinesh K. Kumar ◽  
Ganesh Naik
Keyword(s):  
Muscle Contraction ◽  
Muscle Fatigue ◽  
Root Mean Square ◽  
Linear Regression Analysis ◽  
Maximum Voluntary Contraction ◽  
Voluntary Contraction ◽  
Median Frequency ◽  
Mean Square ◽  
Surface Electromyogram ◽  
The Relationship

The relationship between force of muscle contraction and muscle fatigue with six different features of surface electromyogram (sEMG) was determined by conducting experiments on thirty-five volunteers. The participants performed isometric contractions at 50%, 75%, and 100% of their maximum voluntary contraction (MVC). Six features were considered in this study:normalised spectral index (NSM5), median frequency, root mean square, waveform length, normalised root mean square (NRMS), and increase in synchronization (IIS) index. Analysis of variance (ANOVA) and linear regression analysis were performed to determine the significance of the feature with respect to the three factors: muscle force, muscle fatigue, and subject. The results show that IIS index of sEMG had the highest correlation with muscle fatigue and the relationship was statistically significant (P<0.01), while NSM5 associated best with level of muscle contraction (%MVC) (P<0.01). Both of these features were not affected by the intersubject variations (P>0.05).

scholarly journals Spatial Intensity Map of HDEMG Based Classification of Muscle Fatigue

2021 ◽  
Author(s):  
Navaneethakrishna Makaram ◽  
Sridhar P. Arjunan ◽  
Dinesh Kumar ◽  
Ramakrishnan Swaminathan
Keyword(s):  
Muscle Fatigue ◽  
Tibialis Anterior ◽  
Plantar Flexion ◽  
Tibialis Anterior Muscle ◽  
Maximum Voluntary Contraction ◽  
Real Life ◽  
Voluntary Contraction ◽  
Spatial Intensity ◽  
Intensity Map

In this, study, we have investigated to identify the muscle fatigue using spatial maps of High-Density Electromyography (HDEMG). The experiment involves subjects performing plantar flexion at 40% maximum voluntary contraction until fatigue. During the experiment, HDEMG signal was recorded from the tibialis anterior muscle. The monopolar and bipolar spatial intensity maps were extracted from the HDEMG signal. The random forest classifier with different tree configurations was tested to distinguish nonfatigue and fatigue condition. The results indicate that selected electrodes from the differential intensity map results in an accuracy of 83.3% with the number of trees set at 17. This method of spatial analysis of HDEMG signals may be extended to assess fatigue in real life scenarios.

scholarly journals A video game based hand grip system for measuring muscle force in children

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Mark Gotthelf ◽  
DeWayne Townsend ◽  
William Durfee
Keyword(s):  
Muscular Dystrophy ◽  
Grip Force ◽  
Muscle Force ◽  
Assessment Tool ◽  
Maximum Voluntary Contraction ◽  
Voluntary Contraction ◽  
Assessment System ◽  
Muscle Disease ◽  
Normative Values ◽  
Hand Grip

Abstract Background While new therapies are continuously introduced to treat muscular dystrophy, current assessment tests are challenging to quantify, cannot be used in non-ambulatory patients, or can de-motivate pediatric patients. We developed a simple, engaging, upper-limb assessment tool that measures muscle strength and fatigue in children, including children with muscular dystrophy. The device is a bio-feedback grip sensor that motivates children to complete maximal and fatiguing grip protocols through a game-based interface. Methods To determine if the new system provided the same maximum grip force as what is reported in the literature, data was collected from 311 participants without muscle disease (186 M, 125 F), ages 6 to 30, each of whom played the four minute grip game once. We compared maximum voluntary contraction at the start of the test to normative values reported in the literature using Welch’s unequal variances t-tests. In addition, we collected data on a small number of participants with muscle disease to determine if the assessment system could be used by the target patient population. Results Of the 311 participants without muscle disease that started the test, all but one completed the game. The maximum voluntary contraction data, when categorized by age, matched literature values for hand grip force within an acceptable range. Grip forced increased with age and differed by gender, and most participants exhibited fatigue during the game, including a degradation in tracking ability as the game progressed. Of the 13 participants with muscle disease, all but one completed the game. Conclusions The study demonstrated the technical feasibility and validity of the new hand grip device, and indicated that the device can be used to assess muscle force and fatigue in longitudinal studies of children with muscular dystrophy.

Muscle Fatigue Induced by Sustained Isometric Contraction

1973 ◽  
Vol 15 (1) ◽  
pp. 67-73
Author(s):  
Noorallah V. Gillani ◽  
Dhanjoo N. Ghista
Keyword(s):  
Muscle Fatigue ◽  
Isometric Contraction ◽  
Muscle Tension ◽  
Maximum Voluntary Contraction ◽  
Voluntary Contraction ◽  
Thermodynamic Criterion ◽  
Static Contraction ◽  
Static Effort ◽  
Suitable Measure ◽  
Regional Metabolism

An important potential thermodynamic criterion for the condition of muscle fatigue induced by a single sustained isometric contraction is discussed, and a method is suggested for its use in determining the duration for which any given static contraction will be sustained before the condition of fatigue is reached. In a healthy rested muscle, under given environmental conditions, the production of a critical amount of heat caused by local regional metabolism is postulated as a necessary response to sustained static effort beyond 15% MVC before fatigue can occur. Muscle response is expressed here as a percent of maximum voluntary contraction (% MVC), a relative unit for each group of muscles which is a suitable measure of the actual level of physiological stimulus for any muscle. A relation between static muscle tension, the duration for which such a tension is sustained, and the critical amount of heat produced until the onset of fatigue is derived. It is assumed that the amount of heat liberated in the muscle during regional metabolism can be measured.

Laterality of Hand Grip and Elbow Flexion Power in Right Hand–Dominant Individuals

2009 ◽  
Vol 4 (3) ◽  
pp. 355-366 ◽  
Author(s):  
Hiroki Aoki ◽  
Shinichi Demura
Keyword(s):  
Gender Difference ◽  
Peak Power ◽  
Maximum Voluntary Contraction ◽  
Elbow Flexion ◽  
Voluntary Contraction ◽  
Power Ratio ◽  
Young Males ◽  
Left Hand ◽  
Hand Grip ◽  
Right Hand

Purpose:This study aimed to compare the laterality, and its gender difference, of hand grip and elbow flexion power according to load in right hand–dominant individuals.Results:The subjects were 15 healthy young males (age 22.1 ± 0.7 y, height 171.3 ± 3.4 cm, mass 64.5 ± 4.1 kg) and 15 healthy young females (age 22.4 ± 1.0 y, height 161.1 ± 3.0 cm, mass 55.4 ± 4.6 kg). Isotonic peak power was measured with 6 different loads ranging from 20% to 70% of maximum voluntary contraction (MVC) for grip and elbow flexion movements.Results:The peak power was significantly larger in males than in females in both movements (ratio, males:females was 58.1:49.4%). The dominant right hand had larger peak power in all loads for hand grip power (ratio, dominant:nondominant was 83.6:71.1%) and in loads of 20% to 50% MVC for elbow flexion power (88.7:85.7%) in both genders, confirming laterality in both movements. The peak power ratio of the dominant right hand to the nondomi-nant left hand was significantly larger in hand grip than in elbow flexion for all loads in females.Conclusion:Even though laterality was confirmed in both grip and elbow flexion, gender difference is more marked in hand grip.

scholarly journals EEG-Based Spectral Analysis Showing Brainwave Changes Related to Modulating Progressive Fatigue During a Prolonged Intermittent Motor Task

2021 ◽  
Author(s):  
Easter S. Suviseshamuthu ◽  
Vikram Shenoy Handiru ◽  
Didier Allexandre ◽  
Armand Hoxha ◽  
Soha Saleh ◽  
...  
Keyword(s):  
Muscle Fatigue ◽  
Spectral Power ◽  
Maximum Voluntary Contraction ◽  
Motor Task ◽  
Voluntary Contraction ◽  
Muscle Contractions ◽  
Healthy Population ◽  
Time Frequency ◽  
Beta Power ◽  
Source Level

ABSTRACTRepeatedly performing a submaximal motor task for a prolonged period of time leads to muscle fatigue manifested by its reduced capacity to generate force or power. Fatigue resulted from voluntary muscle contractions comprises a central and peripheral component, which demands a gradually increasing effort to perform the task as time elapses. However, we still lack a complete understanding of brain contribution to the enhancement of effort to cope with progressing fatigue because of repeated submaximal muscle contractions. The knowledge of how the muscle fatigue modulates brain activities in healthy population will help rationalize why certain patients experience exacerbated fatigue while carrying out mundane tasks. The intermittent motor tasks closely resemble many activities of daily living (ADL), thus remaining physiologically relevant to study fatigue. The scope of this study is therefore to investigate the EEG-based brain activation patterns in healthy subjects performing intermittent submaximal muscle contractions until self-perceived exhaustion. Fourteen participants (median age 51.5 years; age range 26 − 72 years; 5 males) repeated elbow flexion contractions at 40% maximum voluntary contraction by following visual cues displayed on an oscilloscope screen until subjective exhaustion. Each contraction lasted ≈ 5 s with a 2-s rest between trials. The force, EEG, and surface EMG (from elbow joint muscles) data were simultaneously collected. After preprocessing, we selected a subset of trials at the beginning, middle, and end of the study session representing brain activities germane to mild, moderate, and severe fatigue conditions, respectively, to compare and contrast the changes in the EEG time-frequency (TF) characteristics across the conditions. The TF analyses were conducted both at the channel and source level. The outcome of channel- and source-level analyses reveals that the theta, alpha, and beta power spectral densities (PSDs) vary in proportion to fatigue levels in cortical motor areas. Importantly, the pairwise PSD differences between the fatigue conditions survived the statistical inferential tests with a p-value threshold of 0.05. We observed a statistically significant change in the band-specific spectral power in relation to the graded fatigue from both the steady- and post-contraction EEG data. The findings would enhance our understanding on the etiology and physiology of voluntary motor-action-related fatigue and provide pointers to counteract the perception of muscle weakness and lack of motor endurance associated with ADL. The study outcome would help evaluate how clinical conditions such as neurological disorders and cancer treatment alter neural mechanisms underlying fatigue in future studies, and develop therapeutic strategies for restoring the patients’ ability to participate in ADL by mitigating the central and muscle fatigue.

scholarly journals Environmental temperature and exercise modality independently impact central and muscle fatigue among people with multiple sclerosis

2017 ◽  
Vol 3 (4) ◽  
pp. 205521731774762 ◽  
Author(s):  
Geetika Grover ◽  
Michelle Ploughman ◽  
Devin T Philpott ◽  
Liam P Kelly ◽  
Augustine J Devasahayam ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Body Weight ◽  
Body Temperature ◽  
Aerobic Exercise ◽  
Muscle Fatigue ◽  
Room Temperature ◽  
Environmental Temperature ◽  
Maximum Voluntary Contraction ◽  
Voluntary Contraction ◽  
Total Body

Background Heat sensitivity and fatigue limit the ability of multiple sclerosis patients to participate in exercise. Objective The purpose of this study was to determine the optimal aerobic exercise parameters (environmental temperature and exercise modality) to limit exercise-induced central and muscle fatigue among people with multiple sclerosis. Methods Fourteen people with multiple sclerosis with varying levels of disability completed four randomized exercise sessions at 65% of the maximal volume of oxygen: body-weight supported treadmill cool (16°C), body-weight supported treadmill room (21°C), total-body recumbent stepper cool and total-body recumbent stepper room. Maximum voluntary contraction, electromyography, and evoked contractile properties were collected from the more affected plantar flexors along with subjective levels of fatigue, body temperature and perceived level of exertion. Results Exercise in cooler room temperature increased maximum voluntary contraction force ( p = 0.010) and stabilized body temperature ( p = 0.011) compared to standard room temperature. People with multiple sclerosis experienced greater peak twitch torque ( p = 0.047), shorter time to peak twitch ( p = 0.035) and a longer half relaxation time ( p = 0.046) after total-body recumbent stepper suggestive of less muscle fatigue. Conclusion Cooling the exercise environment limits the negative effects of central fatigue during aerobic exercise and using total-body recumbent stepper (work distributed among four limbs) rather than body-weight supported treadmill lessens muscular fatigue. Therapists can titrate these two variables to help people with multiple sclerosis achieve sufficient exercise workloads.

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