Posts Tagged motion rehabilitation
[ARTICLE] Experimental Study on Upper-Limb Rehabilitation Training of Stroke Patients Based on Adaptive Task Level: A Preliminary Study – Full Text
During robot-aided motion rehabilitation training, inappropriate difficulty of the training task usually leads the subject becoming bored or frustrated; therefore, the difficulty of the training task has an important influence on the effectiveness of training. In this study, an adaptive task level strategy is proposed to intelligently serve the subject with a task of suitable difficulty. To make the training task attractive and continuously stimulate the patient’s training enthusiasm, diverse training tasks based on grabbing game with visual feedback are developed. Meanwhile, to further enhance training awareness and inculcate a sense of urgency, a dynamic score feedback method is used in the design of the training tasks. Two types of experiments, functional and clinical rehabilitation experiments, were performed with a healthy adult and two recruited stroke patients, respectively. The experimental results suggest that the proposed adaptive task level strategy and dynamic score feedback method are effective strategies with respect to incentive function and rehabilitation efficacy.
Stroke is a cerebral blood circulation disorder, which is mainly divided into hemorrhagic and ischemic stroke based on the pathogenesis . Based on the report , the global prevalence of stroke was 42.4 million in 2015. In China, approximately 13 million individuals are stroke survivors, and the prevalence is increasing, with 2 million new stroke patients yearly . Overall, the mean age of stroke patients worldwide is increasing, whereas the onset of stroke tends to be younger in China  and Sweden . Due to the lack of effective treatment for the disease, stroke is characterized by high mortality and disability. How to effectively treat stroke and reduce the poor consequences is a common problem in the medical field.
Stroke is referred to as a cerebrovascular accident with a sudden decrease in blood supply to the brain tissue, which may result in brain tissue ischemia and brain cell damage. When the brain nerve cells are damaged, the body functions controlled by these nerve cells are impaired. Stroke treatment and rehabilitation are usually divided into two stages, namely, acute and chronic phases of stroke [4, 5]. During the acute phase, the patient’s corresponding function is restored when the impaired neural connections are recovered within the called sensitive time-limited window. Based on neuroplasticity and compensation of brain function theory, in recent decades, many advanced stroke rehabilitation techniques have been developed and utilized, such as robot-aided device , virtual reality , brain stimulation, and constraint-induced therapy, for the patients in the chronic phase of stroke [8, 9]. To aid the patient in recovering the lost function to the greatest extent, these advanced techniques using unconventional drug therapy for the recovery of the patient’s body functions have received increasing attention from researchers for the past few years.
Stroke may be associated with disabilities for the survivor. The disabilities usually affect the activities of daily living, such as motion ability, walking, speech, and cognition [10, 11]. In clinics, motor deficits are some of the most prevalent symptoms, and 69% of stroke patients have some degree of motion disability of the upper extremity . Fortunately, clinic investigations in both human and animal models demonstrate that massive and intensive motion training can induce cortical changes and reorganization, which construct a relative ability to produce skilled action . Thus, motor function improvements beyond the subacute stage might be induced by rehabilitative therapies. Exercise therapy plays an important role in functional recovery and reconstruction, and it is a popular therapeutic method for stroke rehabilitation. Effectiveness of motion training for motor function improvement has been widely reported . In clinics, motion training is usually conducted by a physiotherapist. The traditional hand-to-hand treatment by a physiotherapist has many disadvantages, such as high labor intensity, low efficiency, and rehabilitation effectiveness varying with the physician. To effectively offer stroke patients with modern technology, all kinds of motion training robots are developed to replace the physiotherapist to offer the patient with designed motion training, which presents the advantages with recording process data, high convenience providing task-oriented practice, and high accuracy in measuring outcomes. In recent years, the rehabilitation robot has become a hot topic in the field of robotics. Robotics is increasingly used in poststroke upper extremity rehabilitation . With regard to the upper extremity rehabilitation robot, studies have greatly contributed to the system mechanism design [15, 16], control method [17, 18], rehabilitation training method , visual feedback, and so on . The aim of developing motion-rehabilitation training robots is to help patients affected with motor disability relearn motion skills based on the experience-dependent neural plasticity with robot-aided motion training. How to stimulate the enthusiasm of the subject to the greatest extent is one of the main considered issues throughout the design of the rehabilitation system. Many training or controlling strategies have been adopted to improve training motivation, such as varied training tasks, vivid visual feedback or virtual reality, friendly interaction, and intelligent control methods [21–23]. However, the training task is usually appointed in advance during the robot-aided motion exercise. Too difficult training tasks will lead the trainer to lose confidence, and too easy training tasks will lead to boredom. Therefore, the level of training tasks during one training session needs to be adjusted based on the training performances. Motion training with matching difficulty level can effectively stimulate the enthusiasm of the subject and make the movement undergo better cooperation.
In this study, the training task based on a game with various levels of difficulty was designed to improve the effectiveness of the rehabilitation training for robot-aided free movement training. Moreover, an adaptive strategy for selection of task level and dynamic visual feedback method were adopted; these interventions can provide the patients with the appropriate training task and motivational visual feedback, which may motivate interest in training and participation awareness.
2. Materials and Methods
2.1. Motion Training Type
In clinics, the motion training type of robot-aided rehabilitation exercise is usually varied with the rehabilitant stage and the state of illness. The motion training types are divided into three modes based on the condition that the robot provides auxiliary force: the passive, aided active, and free motions.
The passive motion training is usually utilized in the early recovery phase where the stroke patient does not present any motion ability, and the movement is fully towed by robot following the predefined trajectory. When the stroke patient possesses a certain active ability but cannot completely overcome gravity, the aided active motion is utilized to arouse the active movement consciousness. During the aided active motion, an appropriate aided force is supplied by the robot to help the subject perform training tasks based on the designed control algorithm. Free motion is used in the stage where the subject can fully overcome gravity. Free movement refers to the movement initiated by the patient himself, and the whole movement process is completely self-initiated by the patient. The end of robot manipulation follows the subject’s hand and does not provide any force or any direction guidance for the movement of the patient. Free motion is fully controlled by the trainer, and the exercise process is actually a coordinated control process of body. The active participation of patients is conducive to accelerating the control of the central nervous system reconstruction on the affected limb. Meanwhile, subjects can freely move according to their wishes, which largely increase their confidence and inspire their motion enthusiasm.
With regard to each motion training type, the training form and control strategy are usually different due to the specific characteristics and goals. To increase interest in training, visual feedback techniques are usually used to design and develop free motion training. This study focuses on free movement training and evaluates the effective training methods using an adaptive training strategy and dynamic visual feedback.
2.2. Rehabilitation System Set-Up
The constructed motion rehabilitation system mainly includes two parts: the hardware and software sections. The four-degree-of-freedom Barrett Whole Arm Manipulator (WAM), which has been widely used as an experimental platform in the medical field, was used as the main platform to construct the upper-limb motion rehabilitation system. The Barrett WAM can be well controlled in joint space, and each joint can be driven by setting the control torque; the position of each rotary joint is measured timely. Additionally, the Barrett WAM was designed with cable-driven technology, presenting outstanding back drivability and safety, which is suitable for an ideal hardware platform for motion training. To monitor the interactive force during rehabilitation, a three-dimensional (3-D) force sensor was developed and installed on the end-effector. An arm-support device was designed and installed to support the impaired limb for stroke patients to perform certain types of motion training. In this investigation, the motion rehabilitation system, which is presented in Figure 1, mainly consists of the WAM manipulator, 3-D force sensor, arm-support device, and controlling PC. More detailed information on the constructed motion rehabilitation system can be acquired from our previous studies [24, 25].
Recent neurological research indicates that the impaired motor skills of post-stroke patients can be enhanced and possibly restored through task-oriented repetitive training.
This is due to neuroplasticity – the ability of the brain to change through adulthood. Various rehabilitation processes have been developed to take advantage of neuroplasticity to retrain neural pathways and restore or improve motor skills lost as a result of stroke or spinal cord injuries (SCI).
Research in this area over the last few decades has resulted in a better understanding of the dynamics of rehabilitation in post-stroke patients and development of auxiliary devices and tools to induce repeated targeted body movements. With the growing number of stroke rehabilitation therapies, the application of robotics within the rehabilitation process has received much attention. As such, numerous mechanical and robot-assisted upper limb and hand function training devices have been proposed.
A systematic review of robotic-assisted upper extremity (UE) motion rehabilitation therapies was carried out in this study. The strengths and limitations of each method and its effectiveness in arm and hand function recovery were evaluated. The study provides a comparative analysis of the latest developments and trends in this field, and assists in identifying research gaps and potential future work.
With an ageing population problem increasingly prominent, the number of hemiplegia patients is growing caused by stroke, which has a high morbidity and high mortality rate . Stroke can lead to the dysfunction of the brain central nervous, often characterized by language, cognitive or motor dysfunction , . The medical rehabilitation mechanism of stroke is based on neural plasticity theory and the theory of mirror neurons .
[BOOK CHAPTER] Cable-Driven Robot for Upper and Lower Limbs Rehabilitation: Engineering Book Chapter
The science of rehabilitation shows that repeated movements of human limbs can help the patient regain function in the injured limb. There are three types of mechanical systems used for movement rehabilitation: robots, cable-driven manipulators, and exoskeletons. Industrial robots can be used because they provide a three-dimensional workspace with a wide range of flexibility to execute different trajectories, which are useful for motion rehabilitation. The cable-driven manipulators consist of a movable platform and a base, which are connected by multiple cables that can extend or retract. The exoskeleton is fixed around the patient’s limb to provide the physiotherapy movements. This chapter presents the upper and lower human limbs movements, a review of several mechanical systems used for rehabilitation of upper and lower limbs, as well as the mathematical model of cable-driven manipulators. The experimental tests of the cable-driven manipulator for upper and lower limb rehabilitation movements are presented showing the viability of the proposed structure. Finally, this chapter presents the future research directions in rehabilitation robots.
Stroke is the most common cause of disability in the developed world and can severely degrade lower limb function. The use of robots in therapy can provide assistance to patients during training and can offers a number of advantages over other forms of therapy (Pennycott et al., 2012). Movements’ recovery after stroke is related to neural plasticity, which involves developing new neuronal interconnections, acquiring new functions and compensating for impairment. Stroke rehabilitation programs should include meaningful, repetitive, intensive and task-specific movement training in an enriched environment to promote neural plasticity and movements’ recovery. Robotic training can offer several potential advantages in rehabilitation, including good repeatability, precisely controllable assistance or resistance during movements and quantifiable measures of subject performance. Moreover, robot training can provide the intensive and task-oriented type of training that has proven effective for promoting movements learning (Takeuchi & Izumi, 2013; Colombo et al., 2012; Kuznetsov et al., 2013; Maciejasz et al., 2014, Dzahir & Yamamoto, 2014).
There exist two common techniques for movement rehabilitation: the first technique involves the patient staying passive throughout the therapy while the therapist (or the rehabilitation system) manipulates the injured limb to promote its movement. Motion and load limits must be well controlled in this technique to avoid new injuries of the still injured region/limb. In the second technique, the patient performs active movements. The big difference between patients and injury means different and/or multiple devices should be at the disposal of therapists (Carvalho & Gonçalves, 2012).
One can identify two important areas for the application of robots to human health: the robotic surgery and the rehabilitation robots. Both areas have advanced considerably due to the development of control systems, video cameras, micro and nano technologies, new materials, and so on.
Physical medicine and rehabilitation is intended to treat, recuperate, or alleviate the disabilities caused by chronic diseases, neurological damage, or injuries resulting from pregnancy and childbirth, car accidents, cardiovascular diseases, and work. Rehabilitation is a comprehensive and dynamic process-oriented physical and psychological recovery of the disabled person, in order to achieve social reintegration.
The rehabilitation process involves several activities, from diagnosis to prescription of treatment, where the prescribed treatment must facilitate and stimulate the recovery processes and natural regeneration. In general, the process involves stimulus and repetitive movements that must be performed several times at various speeds.
The science of rehabilitation has shown that repeated movements of human limbs can to help the patient regain function of the injured limb. Robotic systems can be more efficient in performing these exercises than humans, and they the recording of information like position, trajectory, force and velocity. All data can be archived and then compared to check the progress of patients in therapy.
Different robotic architectures have been developed and applied in the rehabilitation of upper and lower human limbs. In general, robotic structures used in rehabilitation are industrial robots or a new structure specifically designed for and/or adapted to the reproduction of human movements.
Robots are mechatronics system that can be used in all fields of modern engineering science and technologies. Mechatronics enables the creation, design, and support of new concepts for realizing intelligent human-oriented machines that coordinate and cooperate intelligently with their human users (Habib, 2007). Thus, this paper focuses on mechatronics system based in cable-driven parallel manipulators which are used in medicine to rehabilitate patients with loss of movement.