Posts Tagged Muscle activation
[Proceeding] Investigation of Upper Arm Muscle Activation for the Progress Monitoring in Stroke Rehabilitation – Full Text PDF
This paper investigates the muscle activation of the upper arm for the progress monitoring of post-stroke rehabilitation. The performance measure is an indicator to monitor the progress of the rehabilitation exercise. The aim is for the fast recovery from the lost function of the upper limb as a result of the paralyzed patients. The investigation results will be employed in virtual reality (VR) game technology in the stroke rehabilitation exercise. It can solve the problem of the conventional stroke therapy which some prove inefficient and even some fail to regain patients’ upper arm. The rehabilitation task requires the muscle activity measurement and monitoring of the progress that involve both fundamental and functional movements. By consistently do the rehabilitation exercise, patients can slowly develop the motor functions, which enables them to slowly regain the movement of the affected limb. In the experiments, five healthy subjects were selected. The experimental results show that deltoid has a significant activation compared with the bicep. In the VR systems, these two muscles will be used to monitor the progress of the rehabilitation.
Stroke is one of the main five driving reasons for death and one of the best 10 foundations for hospitalization in Malaysia. World Health Organization (WHO) statistical profile for Malaysia stated that the stroke was at second position for causes of deaths in Malaysia, killing 15.5 thousand people in 2012. Based on study by Burke and Venketasubramanian , it was stated that Malaysia was at third position for stroke mortality and at fourth placed among causes of death after 1991. Stroke can cause a long-term disability. The major cause of this disability is due to Traumatic Brain Injury (TBI), Spinal Cord Injury (SCI), and Cerebrovascular Accident (CVA) . The outcomes of these ailments are impact on patient’s personal satisfaction as well as likewise confined their execution of everyday life exercises. Motor deficits following stroke are most obvious in the contralesional (inverse of the injury side of the cerebrum) limbs, and may include muscle shortcoming, fatigue, abnormal muscle tone, and joint and muscle contracture [2-4]. In order to recover from this disability, hospitals and clinics had conducted the rehabilitation proses of training with the goals to heal or improve lost function of human motor due to the stroke disease [5-7].
This research is conducted to select the most activated muscle on human body specifically for upper arm muscle in case of measuring the performance of post stroke patient in rehabilitation. The objective of this research is to investigate the motion features of the functional movement by using electromyography (EMG). The significant muscle for the performance measure of the stroke rehabilitation will be proposed. Not to forget the functional pattern or motion pattern will be design to get the better muscle activation performance.
The organization of the paper is as follows. Introduction is given in the first section of this paper. Then, literature review regarding EMG and post stroke rehabilitation will be presented in the following section. Methodology and flow of this work will be explained in detail in the third section. Results of this work can be seen in the fourth section.
Finally, conclusions and future recommendation is also given in the end of this paper.[…]
Motor Control / Muscle Activation / Motor Re-education, whatever you might want to call it — is one of the crucial keys to a successful rehabilitation program especially in sports medicine rehabilitation but is often times overlooked by many clinicians.
What Happens After Injury and How it relates to Motor Control?
Injury causes chemical pain and swelling, both of which have inhibitory effect on muscle’s ability to contract.
“Persistent pain alone will cause muscle weakness due to decrease in neural output” — P. Brukner & K. Khan
Therefore, muscle conditioning or motor control must commence after initial injury along with pain and inflammation management. This process or treatment aims to teach the patient how to activate those muscles that are inhibited following an injury. For example, following a shoulder impingement injury, local stabilizers of the shoulder like the supraspinatus are inflamed and inhibited. Athletes or clients should be taught how to activate and control that damaged muscle before proceeding to other forms of muscle conditioning and/or strengthening.
I have been blessed to grew up in a university and clinics which taughts and applies the practice of activating first the local stabilizers of the body is the first priority rather than taking theshortcut of activating global muscles thinking that if global muscles are activated so do the local stabilizers. But sadly, it is not always the case. I am devastated to see so many clinics trying to fire up global muscles without knowing if local stabilizers are right on point before firing their guns.
“It’s like pulling the trigger of a gun without positioning the gun first to hit it’s target.”
It is important to differentiate what a global muscles and local muscles are. Global muscles are the large, torque-producing muscles, whereas local muscles are responsible for local stability. For example, in the shoulder region, global muscles are your deltoids & upper trapezius, while local muscles are your rotator cuff like supraspinatus and infraspinatus. In the recent years of study, there has been an increasing understanding of the important role of activating first the local stabilizers of the joint before the torque producing global muscles.
When There is No Motor Control..
When there is no motor control, there is a incorrect motor patterning syndrome, especially after injury.
According to the book, Brukner & Khan’s Clinical Sports Medicine (Mcgraw Medical)..“Rehabilitation of these incorrect motor patterning syndrome relies on careful assessment of the pattern of movement, theindividual strength, function of the involved muscles and the flexibility of the muscles and joints. As this abnormal movement pattern has been developed over a lengthy period, it is necessary for the patient to learn a new movement pattern. This takes time and patience.The movement should be broken down into components and the patient must initially learn to execute each component individually.Eventually, the complete correct movement pattern will be learned.”
How To Do Motor Control? Tips and Tricks.
As I practice in clinics, I always use cuing and tactile / verbal feedback to facilitate control of desired movements. For me to feel if the right muscle is being activated I always palpate 2 groups of muscles. One is the muscle in which I want to control or facilitateand another are the groups of muscles which I do not want to be substituting during motor learning. I find this effective in facilitating motor control. Other techniques I use are visualization of the correct muscle action. Also, I often times demonstrate and describe the muscle action to the patient. One technique which I haven’t used yet because it is so time consuming, but I think will be more effective is to have anatomical illustrations of the muscles involved around what you want to monopolize. Use of instructions that cue the correct action also helps. For example, phrases like “pull your navel towards towards your spine” to facilitate control of transversus abdominis. One of the best advise that I would give is to focus on precision. The patient has to concentrate and focus on the precise muscle action to be achieved. It should be stressed that activation of the muscles should be a gentle action. Other muscles should remain relaxed during this localize exercise.
“Do not pull the trigger of gun without positioning the gun first to hit it’s target.”
- Clinical Sports Medicine Revised 3rd Edition by Peter Brukner and Karim Khan
I like to hear it from you. What are your thoughts on these? Do you agree or disagree?
[Abstract] An attempt to explain the Vojta therapy mechanism of action using the surface polyelectromyography in healthy subjects: A pilot study
Rehabilitation according to Vojta is a neurophysiological method used to obtain reflex responses in muscles following stimulation of particular activation zones.
This study aims to objectively evaluate the muscular responses following stimulation according to Vojta’s method. The possible routes of spinal transmission responsible for the phenomenon of muscle activation in upper and lower extremities are considered.
Polyelectromyographic (pEMG) recordings in the upper and lower extremities in healthy volunteers (N = 25; aged 24 ± 1 year) were performed to find out the possible routes of spinal transmission, responsible for muscle activation. The left acromion and right femoral epicondyle were stimulated by a Vojta therapist; pEMG recordings were made including the bilateral deltoid and rectus femoris muscles.
Results and Discussion
Following acromion stimulation, muscle activation was mostly expressed in the contralateral rectus femoris, rather than the contralateral deltoid and the ipsilateral rectus femoris muscles. After stimulation of the lower femoral epicondyle, the following order was observed: contra lateral deltoid, ipsilateral deltoid and the contra lateral rectus femoris muscle.
One of the candidates responsible for the main crossed neural transmission involved in the Vojta therapy mechanism would be the long propriospinal tract neurons.
[Abstract] A Longitudinal EMG Study of Complex Upper-limb Movements in Post-stroke Therapy. 1: Heterogeneous EMG Changes despite Consistent Improvements in Clinical Assessments
Post-stroke weakness on the more-affected side may arise from reduced corticospinal drive, disuse muscle atrophy, spasticity, and abnormal co-ordination. This study investigated changes in muscle activation patterns to understand therapy-induced improvements in motor-function in chronic stroke compared to clinical assessments, and to identify the effect of motor-function level on muscle activation changes.
Electromyography (EMG) was recorded from 5 upper-limb muscles on the more-affected side of 24 patients during early- and late-therapy sessions of an intensive 14-day program of Wii-based Movement Therapy, and for a subset of 13 patients at 6-month follow-up. Patients were classified according to residual voluntary motor capacity with low, moderate or high motor-function. The area under the curve was calculated from EMG amplitude and movement duration. Clinical assessments of upper-limb motor-function pre- and post-therapy included the Wolf Motor Function Test, Fugl-Meyer Assessment and Motor Activity Log Quality of Movement scale.
Clinical assessments improved over time (p<0.01) with an effect of motor-function level (p<0.001). The pattern of EMG change by late-therapy was complex and variable, with differences between patients with low compared to moderate or high motor-function. The area under the curve (p=0.028) and peak amplitude (p=0.043) during Wii-tennis backhand increased for patients with low motor-function whereas EMG decreased for patients with moderate and high motor-function. The reductions included: movement duration during Wii-golf (p=0.048, moderate; p=0.026, high), and Wii-tennis backhand (p=0.046, moderate; p=0.023, high) and forehand (p=0.009, high); and the area under the curve during Wii-golf (p=0.018, moderate) and Wii-baseball (p=0.036, moderate). For the pooled data over time there was an effect of motor-function (p=0.016) and an interaction between time and motor-function (p=0.009) for Wii-golf movement duration. Wii-baseball movement duration decreased as a function of time (p=0.022). There was an effect on Wii-tennis forehand duration for time (p=0.002) and interaction of time and motor-function (p=0.005); and an effect of motor-function level on the area under the curve (p=0.034) for Wii-golf.
This study demonstrated different patterns of EMG changes according to residual voluntary motor-function levels despite heterogeneity within each level that was not evident following clinical assessments alone. Thus, rehabilitation efficacy might be underestimated by analyses of pooled data.
[ARTICLE] The effect of bilateral trainings on upper extremities muscle activation on level of motor function in stroke patients – Full Text PDF
[Purpose] This study was conducted in order to compare muscle activation level on the affected and unaffected limb according to the recovery level of upper limb between bilateral activity with hands clasped and bilateral activity with pilates ring.
[Subjects and Methods] Twenty inpatient who have had a stroke were recruited. Subjects were divided into two groups by the Fugl-Meyer Assessment of Motor Function score of moderately recovered group and well recovered group. The muscles activation of upper extremity and Co-Contraction Ratio (CCR) were analyzed.
[Results] In the muscles activation of the well group, trapezius, anterior deltoid, and triceps muscles of affected side and biceps muscles of both sides were significantly higher when activity with pilates ring than activity with hands clasped. CCR of both side in the well group was significantly decreased during activity with pilates ring and in the moderate group, CCR of affected side was significantly decreased during activity with pilates ring.
[Conclusion] Bilateral activity with a pilates ring is more effective than activity with hands clasped for the facilitation of muscle activation and coordination in stroke patients.
Functional limitation imposed due to a paretic upper limb affects more than 80% of stroke survivors1) . Upper limb impairment is the leading cause of limitation of motor function. Therefore, restoration of upper limb function is an essential aspect of stroke rehabilitation for regaining functional independency2) . An abnormal pattern of upper limb movement may occur caused by the compensation for muscle paralysis and imbalance. By training to perform a functional task, movement re-education is used to treat the abnormal pattern of muscle weakness3) . Although rehabilitation specialists are trying various approaches to facilitate the restoration of upper limb function, rehabilitation of upper limb function remains a challenge. Consequently, a number of researchers and therapists are seeking more effective therapeutic techniques of upper limb rehabilitation to restore voluntary motor control. Bilateral training (BT) is a therapeutic technique of upper limb rehabilitation. A recent meta-analysis revealed that BT has a positive effect on poststroke upper limb rehabilitation4) . BT induces motor synergy between limbs to activate the motor capacity of the affected limb. In other words, voluntary movements of the unaffected limb facilitate voluntary movements of the affected limb5) . Activation of the primary and supplementary motor cortex for the unaffected limb increases voluntary muscle contraction of the affected limb during symmetrical movements6) . Even though BT is performed by using both the unaffected and the affected limbs simultaneously, most studies have reported the effect of BT on the affected limb. Morris & Wijck reported one randomized controlled trial that investigated the effect of BT on the unaffected limb. In that report, subjects were classified into two groups, the bilateral group and unilateral group divided who scored ≤6 on the motor assessment7) . However, no study has addressed the effect of upper limb muscle activation on the unaffected limb during bilateral activity and the comparison of change in activity between the affected and unaffected limbs. The effect of BT on the recovery level of the upper limb remains unclear. BT includes various activities such as targeted reaching activity using a peg, grasping and bringing a glass to the mouth, picking up and placing a towel, and manipulating and playing cards. While various activities are used, it is important to ensure that the movements involve both the upper limbs4) . For assessing bilateral activity, movements involving hand clasped or grasping and lifting up an instrument such as a rod are used. However, no study has investigated the difference in amounts of upper limb muscle activation between bilateral activity with hands clasped and bilateral activity while lifting an instrument. Therefore, the purpose of the present study was to compare the muscle activation level on the affected and unaffected limbs according to the recovery level of the upper limb between bilateral activity with hands clasped and bilateral activity with a pilates ring.
[Review] Motor Imagery-Based Rehabilitation: Potential Neural Correlates and Clinical Application for Functional Recovery of Motor Deficits after Stroke – Full Text PDF
Motor imagery (MI), defined as the mental implementation of an action in the absence of movement or muscle activation, is a rehabilitation technique that offers a means to replace or restore lost motor function in stroke patients when used in conjunction with conventional physiotherapy procedures. This article briefly reviews the concepts and neural correlates of MI in order to promote improved understanding, as well as to enhance the clinical utility of MI-based rehabilitation regimens. We specifically highlight the role of the cerebellum and basal ganglia, premotor, supplementary motor, and prefrontal areas, primary motor cortex, and parietal cortex. Additionally, we examine the recent literature related to MI and its potential as a therapeutic technique in both upper and lower limb stroke rehabilitation.
[Case study] The effect of task-oriented training on the muscle activation of the upper extremity in chronic stroke patients – Full Text
[Purpose] The aim of this study was to determine the effects of task-oriented training on upper extremity muscle activation in daily activities performed by chronic stoke patients.
[Subjects and Methods] In this research, task-oriented training was conducted by 2 chronic hemiplegic stroke patients. Task-oriented training was conducted 5 times a week, 30 minutes per day, for 2 weeks. Evaluation was conducted 3 times before and after the intervention. The Change of muscle activation in the upper extremity was measured using a BTS FreeEMG 300.
[Results] The subjects’ root mean square values for agonistic muscles for the reaching activity increased after the intervention. All subjects’ co-coordination ratios decreased after the intervention in all movements of reaching activity.
[Conclusion] Through this research, task-oriented training was proven to be effective in improving the muscle activation of the upper extremity in chronic hemiplegic stroke patients.
Background: Hemiparetic stroke survivors often exhibit profound weakness in the digits of the paretic hand, but the relative contribution of potential biomechanical and neurological impairment mechanisms is not known. Establishing sources of impairment would help in guiding treatment.
Objective: The present study sought to quantify the role of diminished capacity to voluntarily active finger flexor and extensor muscles as one possible neurological mechanism.
Methods: Two groups of stroke survivors with “severe” (N = 9) or “moderate” (N = 9) hand impairment and one group of neurologically intact individuals (N = 9) participated. Subjects were asked to create isometric flexion force and extension force, respectively, with the tip of the middle finger. The maximum voluntary force (MVF) and the maximum stimulated force (MSF) produced by an applied train of electrical current pulses (MSF) were recorded for flexion and extension. Percent voluntary activation (PVA) was computed from MVF and MSF.
Results: Significant deficits in both MVF and PVA were observed for stroke subjects compared to control subjects. For example, activation deficits were >80% for extensor digitorum communis (EDC) for the “severe” group. Maximum voluntary force and PVA deficits were greater for EDC than for flexor digitorum superficialis (FDS) for stroke subjects with severe impairment. Maximum voluntary force and PVA correlated significantly for stroke subjects but not for control subjects.
Conclusions: Although extrinsic finger muscles could be successfully recruited electrically, voluntary excitation of these muscles was substantially limited in stroke survivors. Thus, finger weakness after stroke results predominantly from the inability to fully activate the muscle voluntarily.
Source: Maney Online – Maney Publishing