I do not have a high level of hand recovery so I look for studies that do not cherry-pick high functioning stroke survivors to test the efficacy of rehab. Many studies with positive results start with stroke survivors who already have beginning finger and thumb movement. To decide how excited to get I look at the outcome measures as well as the statistical differences before and after treatment. Looking at test scores is a good way to decide if research results apply to someone like you.
Franck and his associates studied stroke survivors with no spontaneous hand recovery (1).
Group 1 was taught to keep the affected arm/hand in an “optimal condition” and what to do when discomfort occurred. Before rehab, the highest score on the Fugl-Meyer test was a 9 out of 66 which can be achieved with arm movements like reaching. After 6 weeks of rehab for 4.5 hours per week, the highest Fugl-Meyer score was a 20 which can be achieved with NO hand or wrist movement. After rehab, object manipulation on the Action Research Arm Test (ARAT) improved from 0 to 1 out of 57 for the highest functioning subject. This is the bad news.
Before rehab Group 2 had ARAT scores for object manipulation ranging from 1 to 9 out of 57(1). They were given “high-intensity” therapy to use their hand during functional tasks. Before rehab, the highest Fugl-Meyer score was a 25 out of 66. After 6 weeks of rehab for 6.0 hours per week, the highest Fugl-Meyer score was a 54. This dramatic improvement can be achieved only with hand and wrist movements. After rehab, the highest ARAT score improved from 9 to 42 out of 57.
This dramatic improvement can only be achieved by gaining the ability to pick up objects like a ball.
This is good news because a client’s life can changed when he or she can manipulate objects.
Franck J, Johannes R, Smeets E, Seelen H. Changes in arm-hand function and arm-hand skill performance in patients after stroke during and after rehabilitation. PLOS One. 6/21/2017. doi.org/10.11371/journal.pone.0179453
Between September 2011 and May 2017 Dean published 173 posts about the use of virtual reality to provide rehab for stroke survivors. The results for the hand are depressing. For six years research focused on a subject’s ability to touch an object on the screen so the computer can move an object or make it disappear. Enjoying these quick reactions is not enough to justify the cost of this expensive equipment. It was a good place to start 6 years ago, but progress towards useful gains is disappointing. Stroke survivors want to manipulate objects with their hand.
There is a glimmer of hope. Gauthier (1) used video games that make stroke survivors do more than use their shoulder and elbow to reach forward and side to side. These games require forearm and wrist motions. This may not sound exciting but these motions orient our hand to the many different positions objects rest in. The photo shows the forearm is halfway between palm up and palm down so the hand can pick up a glass. Cocking the wrist means the rim of the glass is not pointed at the ceiling but at the person’s mouth.
Unfortunately, Gauthier selected stroke survivors who already had a few degrees of active forearm and wrist movement. How can subjects make the leap from just reaching to turning their hand palm up to catch a parachute on a video screen? My OT gave me exercises that helped me regain forearm and wrist motions. These small motions have made me more independent. For example, I can turn my hand halfway between palm up and palm down to grab my cane so my sound hand can catch the door before the person in front of me lets it slam shut. I picture stroke survivors practicing forearm and wrist motions and then immediately trying to turn their hand palm up so they can turn over a card on the computer screen. Fun + repetition is good.
1. Gauthier L, et al. Video game rehabilitation for outpatient stroke (VIGoROUS): protocol for a multi-center comparative effectiveness trial of in-home gamified constraint-induced movement therapy for rehabilitation of chronic upper extremity hemiparesis. BMC Neurology. 2017;17-109. doi:10.1186/s12883-017-0888-0.
Pictured here is the experimental setup for the estimation of the 3 DOF human forearm and wrist impedance. (Photo courtesy of UNIST)
Scientists from Ulsan National Institute of Science and Technology (UNIST) have developed a new robotic tool to assess muscle overactivity and movement dysfunction in stroke survivors.
The study was led by Professor Sang Hoon Kang of Mechanical, Aerospace and Nuclear Engineering at UNIST in collaboration with Professor Pyung-Hun Chang of DGIST and Dr Kyungbin Park of Samsung Electronics Co Ltd, according to a media release from UNIST.
In their study, Kang and the others on the team developed a rehabilitation robotic system that quantitatively measures the 3 degrees-of-freedom (DOF) impedance of human forearm and wrist in minutes.
Using their impedance estimation device, which they call the distal internal model based impedance control (dIMBIC)-based method, the team was able to accurately characterize the 3 DOF forearm and wrist impedance, including inertia, damping, and stiffness, for the first time, the release continues.
“The dIMBIC-based method can be used to assist in the quantitative and objective evaluation of neurological disorders, like stroke,” Kang says, in the release. “Findings from this study will open a new chapter in robot-assisted rehabilitation in the workplace accident rehabilitation hospitals, as well as in nursing homes and assisted living facilities.”
The research team expects that, in the long run, the proposed 3 DOF impedance estimation may promote wrist and forearm motor control studies and complement the diagnosis of the alteration in wrist and forearm resistance post-stroke by providing objective impedance values including cross-coupled terms, the release concludes.
[Source(s): Ulsan National Institute of Science and Technology (UNIST), Science Daily]
In 2001, two occupational therapists had one goal: to provide neurological clients access to transformative and life-changing products for improving arm and hand function. Frustrated with the current devices on the market that were limited, expensive, and inaccessible for home use, the founders were inspired to create new, revolutionary solutions.
What started as a dream has now become Saebo, a global provider of affordable rehabilitative products designed to improve mobility and function in individuals suffering from neurological and orthopedic conditions. With a vast network of Saebo-trained clinicians spanning six continents, Saebo has helped over 200,000 clients around the globe achieve a new level of independence.
At Saebo, we have three core product lines for hand rehabilitation: The SaeboFlex, SaeboGlove, and SaeboStretch. These three products have helped numerous people overcome limited motor function after suffering a stroke or other neurological or orthopedic condition.
We would love for you to get to know more about these three products and learn about why they work, and more importantly, who they can help. We have committed to making products that are unique and based on the most recent research and evidence available. Learn about three of our unique products:
SaeboFlex
The SaeboFlex is a high-profile orthosis with an outrigger system that covers the back of hand, fingertips and forearm. This orthosis positions the wrist and fingers into extension to prepare them for object manipulation. With the assistance of the SaeboFlex, the user is able to grasp objects by voluntarily flexing his or her fingers. Once the fingers relax (stop gripping), the extension spring system assists in re-opening the hand to release the object.
Saebo’s functional dynamic orthoses are specifically designed for people suffering from a neurological injury such as a stroke, head injury, and incomplete spinal cord injury. The SaeboFlex gives people the ability to perform grasp-and-release activities, which allows them to participate in task-oriented hand training. Evidence-based research supports this training as critical to recovery. The SaeboFlex is appropriate for individuals with minimal to severe tone/spasticity.
Here is an example of a man trying to pick up a ball six weeks after his stroke with and without the SaeboFlex. You can also see his improvement after six months of training:
SaeboGlove
The SaeboGlove is a low-profile, lightweight glove that helps clients suffering from neurological and orthopedic injuries incorporate their hand functionally in therapy and at home. The proprietary tension system has elastic bands that offer various tensions for individual finger joints. The tension system extends the client’s fingers and thumb following grasping and assists with hand opening.
The ideal candidate for the SaeboGlove is suffering from minimal to no spasticity or contracture. People with more severe soft-tissue shortening would need a high-profile orthosis like the SaeboFlex. For appropriate candidates, the SaeboGlove can be worn to assist with day-to-day functional tasks and during grasp-and-release exercises/activities. This new-found freedom leads to improved motor recovery and functional independence.
This video shows a man attempting grasp-and-release activities with and without the assistance of the SaeboGlove:
SaeboStretch
The SaeboStretch is a soft and adjustable dynamic resting hand splint recognizable for its unique strapping system. This splint is worn to stretch and prevent soft-tissue shortening and helps neurologically impaired clients maintain or improve motion. Saebo’s energy-storing technology allows individuals suffering from spasticity to stretch comfortably and safely, resulting in increased motivation and compliance.
The SaeboStretch is appropriate for people suffering from minimal to moderate spasticity. The orthosis includes the choice of three tension plates that offer various levels of resistance depending on the amount of tone and spasticity the individual has. The flexible hand plates also prevent or minimize joint pain and deformities. The SaeboStretch can be worn during the day or when sleeping.
See how the SaeboStretch is custom fit to the individual in this video:
Our Expert Recommendations
Over the last ten years, Saebo has grown into a leading global provider of rehabilitative products created through the unrelenting leadership and the strong network of clinicians around the world. We are growing this commitment to affordability and accessibility even further by making our newest, most innovative products more available than ever.
If your loved one is recovering from a neurological or orthopedic injury and wants to know if one of Saebo’s products is right for them, take our free 5-minute evaluation. Completing this survey will provide all of the information needed to ensure the best possible product recommendations. Upon completion of your survey, you will receive personalized suggestions tailored to your specific needs and abilities. In addition, our Product Specialists will be happy to review these recommendations with your physician or therapist.
All content provided on this blog is for informational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. If you think you may have a medical emergency, call your doctor or 911 immediately. Reliance on any information provided by the Saebo website is solely at your own risk.
The HandTutor enables functional rehabilitation of the fingers and wrist with biofeedback. It is particularly effective for treatment of neurological and orthopedic conditions.
The movement biofeedback ensures that the patient is motivated and challenged to perform intensive and controlled practice.
The rehabilitation software gives movement instructions and feedback that prevent the development of undesired and compensatory joint movement and ensures better performance of functional tasks.
The system is used by many leading centers worldwide and has CE and FDA certification. More info at http://meditouch.co.il
Rehabilitation robots have become increasingly popular for stroke rehabilitation. However, the high cost of robots hampers their implementation on a large scale. This study implements the concept of a modular and reconfigurable robot, reducing its cost and size by adopting different therapeutic end effectors for different training movements using a single robot. The challenge is to increase the robot’s portability and identify appropriate kinds of modular tools and configurations. Because literature on the effectiveness of this kind of rehabilitation robot is still scarce, this paper presents the design of a portable and reconfigurable rehabilitation robot and describes its use with a group of post-stroke patients for wrist and forearm training. Seven stroke subjects received training using a reconfigurable robot for 30 sessions, lasting 30 minutes per session. Post-training, statistical analysis showed significant improvement of 3.29 points (16.20%, p = 0.027) on the Fugl-Meyer Assessment Scale for forearm and wrist components (FMA-FW). Significant improvement of active range of motion (AROM) was detected in both pronation-supination (75.59%, p = 0.018) and wrist flexion-extension (56.12%, p = 0.018) after the training. These preliminary results demonstrate that the developed reconfigurable robot could improve subjects’ wrist and forearm movement.
It is a challenge to reduce the muscular discoordination in the paretic upper limb after stroke in the traditional rehabilitation programs.
Method
In this study, a neuromuscular electrical stimulation (NMES) and robot hybrid system was developed for multi-joint coordinated upper limb physical training. The system could assist the elbow, wrist and fingers to conduct arm reaching out, hand opening/grasping and arm withdrawing by tracking an indicative moving cursor on the screen of a computer, with the support from the joint motors and electrical stimulations on target muscles, under the voluntary intention control by electromyography (EMG). Subjects with chronic stroke (n = 11) were recruited for the investigation on the assistive capability of the NMES-robot and the evaluation of the rehabilitation effectiveness through a 20-session device assisted upper limb training.
Results
In the evaluation, the movement accuracy measured by the root mean squared error (RMSE) during the tracking was significantly improved with the support from both the robot and NMES, in comparison with those without the assistance from the system (P < 0.05). The intra-joint and inter-joint muscular co-contractions measured by EMG were significantly released when the NMES was applied to the agonist muscles in the different phases of the limb motion (P < 0.05). After the physical training, significant improvements (P < 0.05) were captured by the clinical scores, i.e., Modified Ashworth Score (MAS, the elbow and the wrist), Fugl-Meyer Assessment (FMA), Action Research Arm Test (ARAT), and Wolf Motor Function Test (WMFT).
Conclusions
The EMG-driven NMES-robotic system could improve the muscular coordination at the elbow, wrist and fingers.
Background
Stroke is a main cause of long-term disability in adults [1]. Approximately 70 to 80% stroke survivors experienced impairments in their upper extremity, which greatly affects the independency of their daily living [2, 3]. In the upper limb rehabilitation, it also has been found that the recovery of the proximal joints, e.g., the shoulder and the elbow, is much better than the distal, e.g., the wrist and fingers [4, 5]. The main possible reasons are: 1) The spontaneous motor recovery in early stage after stroke is from the proximal to the distal; and 2) the proximal joints experienced more effective physical practices than the distal joints throughout the whole rehabilitation process, since the proximal joints are easier to be handled by a human therapist and are more voluntarily controllable by most of stroke survivors [2]. However, improved proximal functions in the upper limb without the synchronized recovery at the distal makes it hard to apply the improvements into meaningful daily activities, such as reaching out and grasping objects, which requires the coordination among the joints of the upper limb, including the hand. More effective rehabilitation methods which may benefit the functional restoration at both the proximal and the distal are desired for post-stroke upper limb rehabilitation.
Besides the weakness and spasticity of muscles in the paretic upper limb, discoordination among muscles is also one of the major impairments after stroke, mainly reflected as abnormal muscular co-activating patterns and loss of independent joint control [2, 6]. Stereotyped movements of the entire limb with compensation from the proximal joints are commonly observed in most of persons with chronic stroke who have passed six months after the onset of the stroke, during which abnormal motor synergies were gradually developed. Neuromuscular electrical stimulation (NMES) is a technique that can generate limb movements by applying electrical current on the paretic muscles [7]. Post-stroke rehabilitation assisted with NMES has been found to effectively prevent muscle atrophy and improve muscle strength [7], and the stimulation also evokes sensory feedback to the brain during muscle contraction to facilitate motor relearning [8]. It has been found that NMES can improve muscular coordination in a paralysed limb by limiting ‘learned disuse’ that stroke survivors are gradually accustomed to managing their daily activities without using certain muscles, which has been considered as a significant barrier to maximizing the recovery of post-stroke motor function [9]. However, difficulties have been found in NMES alone to precisely activate groups of muscles for dynamic and coordinated limb movements with desired accuracy in kinematics, for example, speeds and trajectories. It is because most of the NMES systems adopted transcutaneous stimulation with surface electrodes only recruiting muscles located closely to the skin surface with limited stimulation channels [8]. Therefore, the muscular force evoked may not be enough to achieve the precise limb motions. However, limb motions with repeated and close-to-normal kinematic experiences are necessary to enhance the sensorimotor pathways in rehabilitation, which has been found to contribute to the motor recovery after stroke [10]. Furthermore, faster muscular fatigue would be experienced when using NMES with intensive stimuli, in comparison with the muscle contraction by biological neural stimulation [11].
The use of rehabilitation robots is one of the solutions to the shortage of affordable professional manpower in the industry of physical therapy, to cope with the long-term and labour-demanding physical practices [10]. In comparison with the NMES, robots can well control the limb movements with electrical motors. Various robots have been proposed for upper limb training after stroke [12, 13]. Among them, the robots with the involvement of voluntary efforts from persons after stroke demonstrated better rehabilitation effects than those with passive limb motions, i.e., the limb movements are totally dominated by the robots [10]. Physical training with passive motions only contributed to the temporary release of muscle spasticity; whereas, voluntary practices could improve the motor functions of the limb with longer sustainability [10, 14]. In our previous studies, we designed a series of voluntary intention-driven rehabilitation robotics for physical training at the elbow, the wrist and fingers [14, 15, 16, 17, 18]. Residual electromyography (EMG) from the paretic muscles was used to control the robots to provide assistive torques to the limb for desired motions. The results of applying these robots in post-stroke physical training showed that the target joint could obtain motor improvements after the training; however, more significant improvements usually appeared at its neighbouring proximal joint mainly due to the compensatory exercises from the proximal muscles [15, 17]. In order to improve the muscle coordination during robot-assisted training, we integrated NMES into the EMG-driven robot as an intact system for wrist rehabilitation [16, 19]. It has been found that the combined assistance with both robot and NMES could reduce the excessive muscular activities at the elbow and improve the muscle activation levels related to the wrist, which was absent in the pure robot assisted training [16]. More recently, combined treatment with robot and NMES for the wrist by other research group also demonstrated more promising rehabilitation effectiveness in the upper limb functions than pure robot training [20]. However, most of the proposed devices are for single joint treatment, and cannot be used for multi-joint coordinated upper limb training. Furthermore, the training tasks provided by these devices are not easy to be directly translated into daily activities. We hypothesized that multi-joint coordinated upper limb training assisted by both NMES and robot could improve the muscular coordination in the whole upper limb and promote the synchronized recovery at both the proximal and distal joints. In this work, we designed a multi-joint robot and NMES hybrid system for the coordinated upper limb physical practice at the elbow, wrist and fingers. Then, the rehabilitation effectiveness with the assistance of the device was evaluated by a pilot single-group trial. EMG signals from target muscles were used for voluntary intention control for both the robot and NMES parts.
Methods
The NMES-robot system
The system developed is a wearable device as shown in Fig. 1. It can support a stroke subject to perform sequencing limb movements, i.e., 1) elbow extension, 2) wrist extension associated with hand open, 3) wrist flexion and 4) elbow flexion, with the purpose of simulating the coordination of the joints in arm reaching out, hand open for grasping, and withdrawing in daily activities. The starting position of the motion cycle was set at the elbow joint extended at 180° and the wrist extended at 45°, which is also the end point for a motion cycle. In each phase of the motion, visual guidance on a computer screen was provided to a subject by following a moving cursor on the computer screen with a constant angular velocity at 10°/s for the movement of the wrist and the elbow. The subject was asked to minimize the target and actual joint positions during the tracking. In the limb tasks, assistances would be provided from the mechanical motors and NMES at the same time related to the wrist and elbow flexion/extension. NMES alone was applied for finger extension, and there was no assistance from the system for finger flexion (hand grasp). It is because that the main impairment in the hand for persons with chronic stroke is hand open, and the hand grasp can be achieved passively due to spasticity in finger flexors, and one channel NMES has demonstrated the capacity to achieve the gross open of the hand with finger extensions in clinical practices [2]. With the attempt to reduce the overall weight of the system, especially at the distal joints, for the coordinated multi-joint training of the whole upper limb, finger motions were only supported by the NMES in this work. The robot and NMES combined effects on individual finger motions in chronic stroke have been investigated in our previous work [21]. A hanging system was used to lift up the testing limb to a horizontal level (Fig. 1), to compensate the limb gravity and the weight of the wearable part of the system (totally 895 g).
Fig. 1 a The schematic diagram of the experimental setup, b a photo of a subject who is conducting the tracking task with the NMES-robot, c a photo of a subject wearing the mechanical parts of the system, d the configuration of the NMES electrodes and EMG electrodes on a driving muscle. The driving muscles in the study are BIC, TRI, FCR and the muscle union of ECU-ED
The objective of this study was to investigate the effectiveness of functional electrical stimulation (FES) applied to the wrist and finger extensors for wrist flexor spasticity in hemiplegic patients.
Methods
Thirty stroke patients treated as inpatients were included in the study. Patients were randomly divided into study and control groups. FES was applied to the study group. Wrist range of movement, the Modified Ashworth Scale (MAS), Rivermead Motor Assessment (RMA), Brunnstrom (BS) hand neurophysiological staging, Barthel Index (BI), and Upper Extremity Function Test (UEFT) are outcome measures.
Results
There was no significant difference regarding range of motion (ROM) and BI values on admission between the groups. A significant difference was found in favor of the study group for these values at discharge. In the assessment within groups, there was no significant difference between admission and discharge RMA, BS hand, and UEFT scores in the control group, but there was a significant difference between the admission and discharge values for these parameters in the study group. Both groups showed improvement in MAS values on internal assessment.
Conclusion
It was determined that FES application is an effective method to reduce spasticity and to improve ROM, motor, and functional outcomes in hemiplegic wrist flexor spasticity.
Cortical damage after stroke can drastically impair sensory and motor function of the upper limb, affecting the execution of activities of daily living and quality of life. Motor impairment after stroke has been thoroughly studied, however sensory impairment and its relation to movement control has received less attention. Integrity of the somatosensory system is essential for feedback control of human movement, and compromised integrity due to stroke has been linked to sensory impairment.
Methods
The goal of this study is to assess the integrity of the somatosensory system in individuals with chronic hemiparetic stroke with different levels of sensory impairment, through a combination of robotic joint manipulation and high-density electroencephalogram (EEG). A robotic wrist manipulator applied continuous periodic disturbances to the affected limb, providing somatosensory (proprioceptive and tactile) stimulation while challenging task execution. The integrity of the somatosensory system was evaluated during passive and active tasks, defined as ‘relaxed wrist’ and ‘maintaining 20% maximum wrist flexion’, respectively. The evoked cortical responses in the EEG were quantified using the power in the averaged responses and their signal-to-noise ratio.
Results
Thirty individuals with chronic hemiparetic stroke and ten unimpaired individuals without stroke participated in this study. Participants with stroke were classified as having severe, mild, or no sensory impairment, based on the Erasmus modification of the Nottingham Sensory Assessment. Under passive conditions, wrist manipulation resulted in contralateral cortical responses in unimpaired and chronic stroke participants with mild and no sensory impairment. In participants with severe sensory impairment the cortical responses were strongly reduced in amplitude, which related to anatomical damage. Under active conditions, participants with mild sensory impairment showed reduced responses compared to the passive condition, whereas unimpaired and chronic stroke participants without sensory impairment did not show this reduction.
Conclusions
Robotic continuous joint manipulation allows studying somatosensory cortical evoked responses during the execution of meaningful upper limb control tasks. Using such an approach it is possible to quantitatively assess the integrity of sensory pathways; in the context of movement control this provides additional information required to develop more effective neurorehabilitation therapies.
Background
The cerebral cortex plays an important role in feedforward (i.e. voluntary motor drive) and feedback control (i.e. reflexes and modulation of spinal reflexes) of human movement [1]. Cortical damage after stroke impairs both feedforward and feedback control. Altered feedforward control after stroke has been thoroughly studied and may lead to motor impairments such as weakness and abnormal synergy-dependent motor control [2, 3].
Cortical involvement in feedback control (including sensorimotor integration and spinal reflex modulation) requires connectivity between somatosensory receptors in the periphery and the sensorimotor cortex, yet compromised integrity of this somatosensory system after stroke has received little attention in the literature. Understanding the impact of sensory impairment, as well as motor impairment, is highly relevant for the development and selection of neurorehabilitation therapies aimed to enhance and normalize motor control [4, 5, 6, 7] and for evaluating their effectiveness.
Proprioceptive and tactile information are required for feedback control of a joint, and can be studied in an experimental setting by disturbing the joint via a robotic manipulator during motor control tasks. This robotic joint manipulation results in activation of spinal reflex loops [8, 9, 10] as well as in activation of the somatosensory cortex via high-resolution sensory pathways [11]. However, the cortical activity evoked by joint manipulation and consequently the cortical involvement in feedback control have received less attention.
In able-bodied individuals, evoked cortical responses to robotic joint manipulation have been studied with transient [12, 13] and continuous disturbances [14, 15, 16]. Continuous disturbances uninterruptedly provide input to the sensory system, allowing for studying movement control and somatosensory cortical activity during meaningful motor tasks. This study determines the cortical representation of afferent (proprioceptive and tactile) information in individuals with chronic hemiparetic stroke under different upper limb control conditions, relying on objective metrics derived from the electroencephalogram (EEG). Here, the goal is to quantify evoked cortical activation in individuals with chronic hemiparetic stroke, through a combination of robotic continuous joint manipulation of the paretic limb and high-density EEG. The evoked cortical activation reveals the integrity of the connections between sensory receptors in the periphery and the sensorimotor cortices.
It is hypothesized that, due to stroke-induced damage to the somatosensory system, individuals with clinically assessed proprioceptive and tactile impairment will show decreased cortical evoked responses to continuous joint manipulation in the absence of voluntary motor activity of the affected upper limb, as compared to unimpaired persons. In general, when voluntary motor activity of the affected upper limb is required, individuals with hemiparesis have been shown to recruit their contralesional brain hemisphere, i.e. ipsilateral to the movement [17, 18, 19, 20]. It is unclear, however, what this recruitment means with regard to somatosensory (i.e. afferent) evoked cortical activity, as the anatomical pathways conducting proprioceptive and tactile information mainly connect to the contralateral hemisphere [21]; thus, increased evoked cortical activation of the ipsilateral hemisphere is not expected.
Fig. 1 Experimental setup. a The forearm of the participant is strapped into an armrest and the hand is strapped to the handle of the robotic manipulator, requiring no hand force to hold the handle. b Visual feedback as presented to the participant. The circle and crosshairs are always visible. The yellow arrow is only visible during the active task and points up if the target torque is applied. c Close-up of the arm in the robotic manipulator. The wrist joint is aligned with the axis of the motor and is placed in the neutral angle, defined as 20° wrist flexion. d One period of the disturbance signal applied to the wrist (root-mean-square of 0.02 rad). Zero radians corresponds to the neutral angle of the wrist
[Purpose] The aim of this study was to investigate the effects of repeated vibratory stimulation to muscles related to hand functions on dexterity, strength, and sensory function in patients with chronic stroke.
[Subjects and Methods] A total of 10 stroke patients with hemiplegia participated in this study. They were divided into two groups: a) Experimental and b) Control, with five randomly selected subjects for each group. The experimental group received vibratory stimulation, while the control group received the traditional physical therapy. Both interventions were performed for 30 minutes each session, three times a week for four weeks.
[Results] There was a significant within-group improvement in the box and block test results in both groups for dexterity. Grip strength improved in both groups but the improvement was not statistically significant.
[Conclusion] The vibratory stimulation activated the biceps brachii and flexor carpi radialis, which increased dexterity to grasp and lift the box and block from the surface. Therefore, repeated vibratory stimulation to muscles related to hand functions improved hand dexterity equality to the traditional physical therapy in patients with chronic stroke.
