Upper limb muscle

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Aerobic exercise modulates intracortical inhibition and facilitation in a nonexercised upper limb muscle

Aerobic exercise modulates intracortical inhibition and facilitation in a nonexercised upper limb muscle

and a significant suppression of SICI was evident at 30 mi- nutes post-exercise. While LICI displayed a similar trend to SICI, in this case the decrease in inhibition was not sta- tistically significant. In contrast, the S-R curves indicate that the resting motor threshold was not modulated by ex- ercise. There were no significant differences observed in MEP amplitudes pre- and post-exercise at any intensity. Thus, resting motor thresholds of inactive muscles appear unchanged by exercise. However, the current results indi- cate that aerobic activity using the lower limbs causes an immediate and sustained modulation of intracorti- cal facilitation and inhibition of an upper limb muscle. Such excitability changes are a necessary precursor to the relatively more permanent changes in synaptic strength seen in the processes of long-term potentiation (LTP) and long-term depression (LTD). It is likely that the altered ex- citability state of these interneuronal pools will render them more receptive to strategies aimed at inducing plas- ticity, such as skilled motor training or targeted rehabilita- tion, when they are preceded by an exercise session. Furthermore, interventions that directly target the mechanisms of LTP/LTD, such as repetitive theta-burst stimulation (TBS), may benefit from the addition of exer- cise. It should be noted, however, that the benefits of such interventions will not necessarily be additive. The emer- ging principles of homeostatic metaplasticity suggest that

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The effect of arm weight support on upper limb muscle synergies during reaching movements

The effect of arm weight support on upper limb muscle synergies during reaching movements

Our results showed a relatively low degree of dimension- ality reduction provided by the muscle synergies. In our study, the variability in 14 EMG envelope time series was explained by 8 muscle synergies. Previous studies that analyzed muscle synergies for arm reaching movements showed a higher degree of dimensionality reduction. Flanders and colleagues found 2 muscle synergies from 9 muscles [17]. Sabatini found 2 or 3 synergies from 6 muscles [20]. d’ Avella and colleagues found 5 or 6 syner- gies from 19 muscles [18,19]. Cheung and colleagues found 7 synergies from 16 muscles [15]. The above- referenced results are not directly comparable with ours and among them because of the differences in the muscles monitored in each study, the task contingencies, the EMG pre-processing procedures, and the factorization method utilized by different authors in different studies. None- theless, we noticed that one factor contributing to the low degree of dimensionality reduction is the presence of muscle-specific synergies, or synergy vectors do- minated by single muscles (i.e., synergies S6 and S8). Muscle-specific synergy vectors have been previously reported [20]. How these muscle-specific synergy vec- tors should be interpreted is a topic under discussion. Such synergies could represent muscle-specific control commands generated by the CNS [56]. However, some authors consider them to be artifacts arising from the assumptions behind the specific factorization algorithm used. In fact, Sabatini excluded any muscle-specific syn- ergy from the analysis of his results [20].

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Classify EMG data for upper limb muscle based on different movement of arm rehabilitation device

Classify EMG data for upper limb muscle based on different movement of arm rehabilitation device

By minimizing all these factor of noises, the quality of EMG signal will be much better and the analysis of the information will be less of error and easy to obtained. However, the precautions of handling the hardware and the electrode are needed. Figure 2.3 shows the several of electrodes that may use in collecting the EMG signals. This various type of electrodes depends on the size, radius and shape that might be use on skin surface. The shape and the size are depending on the area of muscles to detect and the thickness of the skin. If the skin is thick and the area of belly muscle is large, larger area of electrodes might be use for a better signals detection. Acquisition data play the important role to maximizing the quality of the EMG signal, such as minimizing the distortion in EMG signal, using any filtering tools are not recommended. In terms of signal-to- ratio(SNR) the information that carried in SNR should contain the maximum information of EMG signal [6][17]. Moreover, the quality of EMG signal is affected by the environment, also known as control environment. The environment has to set with minimizing the noise factor. The ambient noise sourced by electromagnetic devices such as radio transmission devices, fluorescent lights and power line interference from electrical wires.[17][10] These ambient noise and motion artifact can be reduced by the proper electrode placements, circuit configuration and control environment.

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The Armeo Spring as training tool to improve upper limb functionality in multiple sclerosis: a pilot study

The Armeo Spring as training tool to improve upper limb functionality in multiple sclerosis: a pilot study

it is supportive to notice that the reported effects of Armeo Spring training in MS are in concordance with the outcomes of a recent randomized clinical trial (RCT) in stroke patients with chronic hemiparesis (cf. two dis- tinct pathologies showing similar upper limb dysfunction caused by upper motor neuron lesions) [13]. This RCT also demonstrated, subsequent to 8 weeks of gravity-sup- ported T-WREX training, functionally relevant changes in the use of the affected upper limb in terms of signifi- cantly improved patient-rated MAL scores, besides sig- nificant gains in active reaching ROM and the FM. In both studies in MS and stroke, handgrip force measured with the Jamar showed no significant alteration. This might be because especially proximal muscles around the shoulder girdle, shoulder and elbow joint were exercised during the execution of virtual reality tasks. The pres- sure-sensitive handle integrated in the exoskeleton sys- tems effectively allows grasp and release exercises, but these only need to be performed submaximally in part of the tasks. In present research, the MI measuring overall upper limb muscle strength improved, albeit non-signifi- cant. A less pronounced gain in strength is not entirely surprising given that the Armeo Spring(/T-WREX) device provides anti-gravity support, notwithstanding the fact that this support had (slightly) decreased in all sub- jects at the end of the training period.

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Case Report Successful outcome of intra-arterial tissue plasminogen activator treatment for patient with acute middle cerebral artery occlusion beyond the 6-hour time window: case series report of 3 middle-aged and aged patients

Case Report Successful outcome of intra-arterial tissue plasminogen activator treatment for patient with acute middle cerebral artery occlusion beyond the 6-hour time window: case series report of 3 middle-aged and aged patients

An 82-year-old female had sudden onset of hemiplegia and global aphasia. The patient had medical history of hypertension for 5 years, dia- betes for 9 years. Neurological examination showed aphasia, paralysis of the left central facial muscle and tongue, and a Babinski sign on the left. The symptoms became worse approximately 4.5 hr after onset: blood pres- sure elevated to 220/98 mmHg, both eyes star- ing to the right, the left upper limb muscle strength graded as level 0, the left lower mus- cle strength graded as level 2 and NIHSS grad- ed as 12. Laboratory tests showed a blood glucose level of 8.3 mmol/L (normal range 3.9-6.1).

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EMG Classification Based On Features Reduction Using Fuzzy C-Means Clustering Technique

EMG Classification Based On Features Reduction Using Fuzzy C-Means Clustering Technique

There are several problems based on the Electromyography (EMG) classification based on features reduction using fuzzy c-means clustering technique. First of all, EMG classification is not an easy task due to the signal contains a lot of uncertainties that leads to a high dimensional feature vector because it controlled by the nervous system and depends on the movement of the upper limb muscle. Based on the result of the EMG signal is the important way to detect the condition of the nerves or muscle.

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Long-term effects of low-intensity training with slow movement on motor function of elderly patients: a prospective observational study

Long-term effects of low-intensity training with slow movement on motor function of elderly patients: a prospective observational study

As a result of training for 12 months, significant im- provements in lower limb muscle strength and systolic blood pressure were observed in the LST group and in the MT group. No significant differences were found between the LST and MT group at the 3-month interval. Studies of active, healthy, elderly people compared weight training using body weight at normal speeds and slow speeds, and it was reported that upper limb muscle strength, lower extremity muscle strength, and max- imum extension leg muscle strength improved in both groups [25]. In our study, elderly subjects performed training using chairs and bars. Our findings showed that such types of LST also improved motor function, and that the effects were similar to those of LST using exercise machines.

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Extra upper limb practice after stroke: a feasibility study

Extra upper limb practice after stroke: a feasibility study

There are limitations to this study. First, the use of one AbleX device limited the number of adults who could complete the extra upper limb practice program at one time and in some circumstances, recruitment was stopped to ensure delivery of the intervention. While the enroll- ment of 48% of the eligible participants is comparable to other studies [42], access to more than one AbleX pro- gram, or use of the GRASP program alone, may improve the recruitment of future studies. Second, the high rate of early discharge; participants completed the extra upper limb practice program for a mean of 3 weeks, delivered over a mean of 20 sessions. This suggests that future trials either need to continue the program after discharge or re- duce the duration from 4 to 3 weeks. Third, while the clin- ical outcomes suggest a promising improvement in upper limb activity and grip strength, it must be noted that all participants had some movement at the time of recruit- ment, which suggests they were capable of recovery due to having had an intact corticospinal tract [43]. Fourth, the use of assessors who were aware of the study aims may have led to bias estimates of clinical outcomes.

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Prediction of muscle activity during loaded movements of the upper limb

Prediction of muscle activity during loaded movements of the upper limb

The long-term goal of this work is to develop an upper limb neuroprosthetic to greatly expand motor function in individuals paralyzed as a consequence of spinal cord injury or stroke. As we have shown here and elsewhere [17-19], machine-learning methods can be used to predict complex patterns of muscle activity associated with a wide array of upper-limb movements based primarily on hand trajectory information. In the present study, we have also shown that inclusion of tactile force signals enables accurate estimation of EMG signals during grasping and movement of objects with the hand. It seems feasible, therefore, that predicted patterns of muscle activity associ- ated with a desired limb trajectory and hand contact forces could be translated into patterns of amplitude and frequency modulated stimulus pulses [20] to elicit movements in paralyzed subjects. Desired movement trajectories (which serve as inputs to the ANN) could be identified in a number of ways. For example, EMG activity recorded from non-paralyzed muscles that are naturally engaged during attempted movements can be used to predict desired limb kinematics [49,50]. Also, in the case of stroke-related hemiplegia, desired movements of the paretic limb could be detected from sensors placed on the contralateral unimpaired limb [51]. It also seems feasible that straight-line reach trajectories to targets in peri-personal space could be identified using glasses- mounted displays and eye-tracking devices. Ultimately, desired hand trajectories could also be identified directly from recordings made in the cerebral cortex [52-56]. Such cortical control of FES could further capitalize on learning and neural plasticity to partially adjust for errors in the transformation of desired movements into patterns of muscle stimulation. If combined with contact forces detected with tactile sensors, such an integrated system could provide appropriate patterns of muscle stimulation needed to elicit desired motor behaviors and thereby reinstate a measure of voluntary control over the patient ’ s own limb.

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An unusual case of unilateral supernumerary extensor carpi radialis muscle

An unusual case of unilateral supernumerary extensor carpi radialis muscle

The limb musculature develops from paraxial meso- derm, and in the seventh week of development appears as a condensation of mesenchyme, near the base of the limb buds [15]. With elongation of the limb buds, the muscle tissue splits into flexor and extensor compo- nents, which then fuse and form a single muscle mass, so the muscles of the superior limb are composed from tissue derived from several segments, specifically, the lower five cervical and upper two thoracic segments. Under myogenic regulatory factors, some muscle pri- mordia of this muscle mass suffer a cell-death. The persistence of cells not-undergoing into the process of cell-death may explain an additional muscle [17]. Studies made on animals [5], revealed that the ECRL and ECRB muscles differs markedly amongst species in the animal classification system. Cossu and Guintard [5] described two muscles in human, a single muscle in sheep and intermediate states (division in the distal third) in other species, like dog and cat, evolution ac- companied by modification of blood supply. In human each muscle is irrigated by a distinct arterial system, in cat two distinct branches for each head of extensor carpi radialis muscle, and in dog and sheep by a single branch from the transverse ulnar artery. Regarding the innervation of ECRL, even when the muscle is separate in two slips, they share the innervation from the radi- al nerve. In human the three-dimensional modelling study reveal one primary branch from the radial nerve proper divided into anterior and posterior branches, that supplied the superficial and deep region of ECRL muscle belly, so the muscle demonstrate neuromuscular compartmentalisation based on intramuscular innerva- tion [13]. So the presence of a supernumerary muscle can be considered an expression of atavism, and most muscle anomalies are referable to an underexpression of particular developmental factors [2].

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Biomechanics of the Hominin Upper Limb: Entheseal Development and Stone Tool Manufacture

Biomechanics of the Hominin Upper Limb: Entheseal Development and Stone Tool Manufacture

124 intrinsic muscles of the thumb and fifth finger (including Mm. flexor carpi ulnaris, flexor pollicis brevis, flexor digitorum profundus 2 and 5, abductor digiti minimi, dorsal interosseous 1, opponens pollicis). These muscles work to cup the hand in order to accommodate and stabilise stones in the hand through forceful opposition of the thumb and fifth finger. Other grips elicit greater recruitment from the extrinsic muscles, such as M. flexor pollicis longus (FPL), though experiments differ in which grip specifically is attributed to generating strongest recruitment for this muscle. Marzke et al. (1998) reports the power (squeeze) grip as eliciting greatest activity from FPL whereas Hamrick et al. (1998) report this to be the three- and four-jaw chuck grips. Marzke (2013a) attributes this contradiction to differences in trial length and fatigue in subjects participating in behaviours requiring repeated strong recruitment of FPL, suggesting that compensatory alterations in thumb function may arise as a result. While Marzke does not remark on it, differences in skill and sample size may also play a role. Marzke et al. (1998) monitor more muscles per subject but their sample size is limited to three individuals across a range of knapping skill levels, including an expert and a proficient. This differs from Hamrick et al. (1998) who studied nine subjects participating in a variety of prehensile behaviours, not just stone knapping, all of an unknown skill level. Nonetheless, Marzke and colleagues relate the high recruitment of the intrinsic muscles of the thumb, index, and fifth finger regions to increases in first and fifth metacarpal robusticity, large tendon and muscle moment arms, and increased entheseal complexity in the hand bones.

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Effects of early and intensive neuro-rehabilitative treatment on muscle synergies in acute post-stroke patients: a pilot study

Effects of early and intensive neuro-rehabilitative treatment on muscle synergies in acute post-stroke patients: a pilot study

Background: After a stroke, patients show significant modifications of neural control of movement, such as abnormal muscle co-activation, and reduced selectivity and modulation of muscle activity. Nonetheless, results reported in literature do not allow to unequivocally explain whether and, in case, how a cerebrovascular accident affects muscle synergies underlying the control of the upper limb. These discrepancies suggest that a complete understanding of the modular re-organization of muscle activity due to a stroke is still lacking. This pilot study aimed at investigating the effects of the conjunction between the natural ongoing of the pathology and the intense robot-mediated treatment on muscle synergies of the paretic upper limb of subacute post-stroke patients. Methods: Six subacute patients, homogenous with respect to the age and the time elapsed from the trauma, and ten healthy age-matched subjects were enrolled. The protocol consisted in achieving planar movement of the upper limb while handling the end-effector of a robotic platform. Patients underwent 6 weeks long treatment while clinical scores, kinematics of the end-effector and muscle activity were recorded. Then we verified whether muscle coordination underlying the motor task was significantly affected by the cerebrovascular accident and how muscle synergies were modified along the treatment.

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A study of upper limb ischemia.

A study of upper limb ischemia.

Several other muscular anomalies exist, mostly involving thickened muscle branches encompassing nerves, for example, slips of anterior scalene between the C5 and the C7 nerve roots or even a bulky muscle anteriorly displacing the nerves. Reports have been made of these muscle fibers becoming incorporated into the epineurium of these nerves as well. One particularly interesting configuration is when a fibrous band stretches over the proximal C5 nerve. Muscular spasm of the neck and shoulder can then lead to direct compression, with upper cord symptoms.

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Parkinson's Patients' Upper and Lower Limb Motor Impairments Differentially Influence Action Verb Processing

Parkinson's Patients' Upper and Lower Limb Motor Impairments Differentially Influence Action Verb Processing

patients with either greater upper or greater lower limb impairment differentially process hand- related (reach) and leg-related verbs (run). In addition, I explored how processing of mental action words such as think and admire are affected in PD. I found that arm-related action words are processed more slowly than leg-related action words in PD patients with greater upper limb impairment, whereas there was no difference in PD patients with greater lower limb impairment. Surprisingly, processing of physical and mental action words were not impaired in PD patients relative to controls. I interpret these results in terms of a functional and selective role of the motor system in language comprehension of body-part-specific action concepts. The results provide support for the view that conceptual representations are grounded in modality-specific experiences.

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Role of Muscle Synergies in Real-Time Classification of Upper Limb Motions using Extreme Learning Machines

Role of Muscle Synergies in Real-Time Classification of Upper Limb Motions using Extreme Learning Machines

intention by means of EMG signals [46]. Therefore, the online classification metrics allowed to estimate the relia- bility of the decoder for both EMG and Synergy features and compare them. In the work by Jiang et al. [49], the authors claim that a perfect model relating muscle activity to control outputs is not essential, but rather continuous interaction and adaptation of the user with the myo- electric interface through feedback can help in achieving reliable performance. Irrespective of whether the model is intuitive or not, users are still capable of learning the inverse dynamics of the model itself, and its mapping function [50]. The level of intuitiveness of the model and the time taken for familiarization with the decoder, are factors which influence the improvement in performance. In our experiments, each motion-class was performed 20 times by each subject during the online testing, and yet we did not observe a consistent learning trend (Tables 1 and 2); which means that the optimum level of learning has not been reached yet: relatively to our primary tar- get, which was the comparison between two extraction features, the absence of a learning trend or adaptation is not detrimental and does not affect the final results. Since the number of repetitions is constant in both the

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Design and implementation of a novel lightweight soft upper limb exoskeleton using pneumatic actuator muscles

Design and implementation of a novel lightweight soft upper limb exoskeleton using pneumatic actuator muscles

While performing above analysis, it is also recommendable to extend FEA to analysis the extension and contraction while bending. This will help to understand the behaviour and the range of motion of the McKibben muscle better. Above analysis can be then extend to the whole EpMAE prototype and to evaluate analytically the arm performance as one piece. Lack of real-time measurements for angles was the main reason behind absence of real-time control for whole EpMAE prototype. Therefore real-time angle measurements by any motion capture system such as VICON or Kinect will be helpful in providing feedback signal that can utilise designed controllers in previous section and inverse kinematic of the EpMAE. In our design also we have not considered motions such as pronation and supination, which are also required for elbow rehabilitation. In order to achieve this more pneumatic muscle actuators should be used in different direction to force the elbow joint to rotate. Moreover, another test should be conducted to understand the behaviour of the pMA when the angle is 54.7° whether it twists or not.

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Design and Implementation of an Antagonistic Exercise Support System Using a Depth Image Sensor

Design and Implementation of an Antagonistic Exercise Support System Using a Depth Image Sensor

infirmity. Effective ways of preventing dementia are thought to include lifestyle and dietary improvements, social activity, and appropriate exercise [2], [3]. Also, methods that combine motor function and cognitive function exercises have been reported to be highly effective [4]. Antagonistic exercises aim to prevent dementia by having people perform different movements with the upper and lower limbs on the left and right sides as a way of exercising motor function and cognitive function simultaneously [5], [6]. By having people perform different actions with the left and right arms and legs, these actions stimulate both the brain and the body by providing simultaneous mental and physical exercise. A study that examined the effects of antagonistic exercise showed that this exercise is effective at preventing the decline in cognitive function [7].

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Limb muscle development

Limb muscle development

During embryonic development, and before functional innerva- tion, a highly stereotopic pattern of slow- and fast contracting primary muscle fibers is established within individual muscles of the limbs, from distinct populations of myoblasts (Nikovits et al., 2001). The fibers can be distinguished by distinct morphological and biochemical properties (Seed and Hauschka, 1984; Stockdale, 1992) and classified by different specific isoforms of the myosin heavy chain (MyHC) (Miller and Stockdale, 1992; DiMario and Stockdale, 1997). Nikovits et al. (2001) have concluded that an intrinsic commitment to either a fast or a slow fiber-type lineage occurs in myogenic precursors while still within the somite. This is in accordance with data of fiber type specification in zebrafish (Blagden et al., 1997; Currie and Junghans, 1996; Du et al., 1997). Cann et al., 1999 was able to show that in explant cultures of avian somites exogenous Shh leads to a marked expansion of the slow fiber population. It has been suggested that selective amplification of committed myoblasts to form fast- or slow fibers occurs in response to proliferative signals that originate in the limb stroma (Nikovits et al., 2001).

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Application of Low-Intensity Modified Constraint-Induced Movement Therapy to Improve the Affecter Upper Limb Functionality in Infantile Hemiplegia with Moderate Manual Ability. Case Series Rocío Palomo-Carrión 1, Rita-Pilar Romero-Galisteo 2* , Elena Piñe

Application of Low-Intensity Modified Constraint-Induced Movement Therapy to Improve the Affecter Upper Limb Functionality in Infantile Hemiplegia with Moderate Manual Ability. Case Series Rocío Palomo-Carrión 1, Rita-Pilar Romero-Galisteo 2* , Elena Piñero-Pinto 3, Purificación López-Muñoz 1, Helena Romay-Barrero1 and Francisco-García-Muro 4

The improvement in the quality of movement was shown by the greater progress in the results obtained between the baseline and fourth measurements of the variables of dissociated movements and grasp. Appreciable benefits were obtained in each measurement produced by the acquisition of a more corrected posture of the trunk, head and shoulders in the execution of the grasp activities, present from the second measurement (after a week of treatment with mCIMT). A dynamic joint position occurred in wrist and elbow extension, increasing the median value for wrist extension by 21º from the baseline to the fourth measurement. In addition, the value reached in the fourth measurement for the median was 81.50º in the active supination of the forearm, allowing for greater control and support of the body structures for the execution of dissociated movements, grasp, weight bearing and protective extension due to the improvement of both active movements. There was a favorable evolution in the dynamic joint position of the affected upper limb due to the gain of active degrees for movement restriction in extension and supination, obtaining an increase for this variable of 10.42% at the end of the treatment. In this way, the activities proposed during the evaluation were performed with greater ease of movement, such as eating a cookie, touching the opposite ear, picking up coins, opening a bottle or throwing a large ball, which requires the selective motor control of certain muscles. In comparison with the results obtained in the quality of movement of the affected upper limb in the present study, we highlight an investigation[24] on mCIMT, which published positive results in the assessment of the quality of movement of motor skills (measured through the Quest scale) using an intervention protocol of 3 weeks of treatment with an intensity of 6 hours per day of restriction and repetitive work. This study demonstrated the effectiveness of the intervention, as it had a larger sample and a control group (18 children with hemiplegia, 9 children in the experimental group and 9 children in the control group).

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Effect of vibration on upper limb spasticity and function in children with hemiplegic cerebral palsy

Effect of vibration on upper limb spasticity and function in children with hemiplegic cerebral palsy

The prime factor for improvement in reaching in the conventional group could be due to decrease in spasticity as a result of weight bearing and multidirectional reaching. Practice of functional activities like reaching in various directions while sitting upright have the potential to train aspects of muscle performance such as coordination, strength, endurance, physical conditioning as well as motor learning as reaching tasks resembled items of PRT. [41] Since the exercises simulated the multidirectional movement and context of movement, neuromuscular organization to movement occurs. [42] Thus, this can be transformed as an improved performance on PRT score. Schneiberg Set al. (2010) found in their study that functional reaching in mutidirection improves reaching, increase degree of elbow extension and increase shoulder flexion and abduction. [43]

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