Rehabilitation Medicine is Changing: Use Tech to Keep Up
The needs of patients are continually evolving just as the aging population continues to grow. Advancements in neurological rehabilitation help top facilities keep the best talent and optimize outcomes in the face of increasing stroke events.
A delicate balance
For neurorehabilitation therapy, there is a delicate balance between available resources and their ever-increasing demand. As demographics change and the global population ages, the healthcare system faces an even heavier economic burden. Experts estimate that stroke rates in Europe will increase by 30% by the year 20501. Improved acute care translates to a growing need for rehab. Limited time with a therapist and a shrinking work force translates to a significant gap in rehabilitation needs versus the availability of care.
A growing senior population
It is a well-known fact that in the coming years, the majority of the world’s population will be advanced in age.2 Many aging individuals will experience health complications such as neurological or cardiovascular diseases that require rehabilitative care.3 As acute medical care and survival rates improve, so does the urgent need for rehabilitation. If current rehabilitation practices do not change, hospitals and other medical facilities will likely struggle to accommodate their patients.
Limited Therapist Time
Reports show that even in top European rehab facilities, only a few hours a day are devoted to hands-on care.4 While intensity and repetition have been shown to produce the best clinical outcomes in neurological or physical rehab programs, the majority of a patient’s time in the hospital is spent idle. To maximize therapy time, a change in how rehabilitation is administered would likely benefit patients and providers tremendously. One such change includes technology-assisted training.
Emerging Trends in Biotech
Robotic rehabilitation has been shown to be as effective, if not more effective than conventional care5,6. In addition to facilitating more intense and thorough rehab for patients, this technology confers benefits such as:
Empowerment – by giving real-time feedback and promoting autonomy, technology helps patients heal themselves. The internet has also led to increased patient knowledge — a significant boon when handled appropriately by health care professionals.
Telemedicine – patients can connect to the best doctors through remote care, allowing them to heal from home. National healthcare systems have successfully reduced the length of inpatient rehabilitation via alternatives like telerehabilitation so that patients can continue their training after discharge.
Gamification – increases patient engagement in rehab practice through play. Not only for pediatric patients, games and virtual reality can help older patients remain motivated to complete rehab programs.
Body sensors – provide real-time, accurate and digital measurements for feedback and optimal care. Incorporating body sensors, virtual reality and gamification can provide an immersive therapy experience with digital precision.
Exoskeletons and prosthetics – enable movement assistance that stabilizes patients and helps them to walk and to complete daily life activities when they would never have been able to achieve this before.
As rehabilitation facilities incorporate new technologies, patient care will become more efficient. Technology enables hospitals to better meet the needs of a growing senior population while preventing therapist burnout in therapists — ultimately making world-class care a reality.
1 Norrving B, Barrick J, Davalos A, et al. Action Plan for Stroke in Europe 2018-2030. Eur Stroke J. 2018;3(4):309–336. doi:10.1177/2396987318808719 2 Beard JR, Officer A, de Carvalho IA, et al. The World report on ageing and health: a policy framework for healthy ageing. Lancet. 2016;387(10033):2145–2154. doi:10.1016/S0140-6736(15)00516-4 3 Béjot Y, Bailly H, Graber M, Garnier L, Laville A, Dubourget L, Mielle N, Chevalier C, Durier J, Giroud M. Impact of the Ageing Population on the Burden of Stroke: The Dijon Stroke Registry. Neuroepidemiology. 2019;52(1-2):78-85. doi: 10.1159/000492820. Epub 2019 Jan 2. PubMed PMID: 30602168. 4 De Wit L, Putman K, Dejaeger E, Baert I, Berman P, Bogaerts K, Brinkmann N, Connell L, Feys H, Jenni W, Kaske C, Lesaffre E, Leys M, Lincoln N, Louckx F, Schuback B, Schupp W, Smith B, De Weerdt W. Use of time by stroke patients: a comparison of four European rehabilitation centers. Stroke. 2005 Sep;36(9):1977-83. doi: 10.1161/01.STR.0000177871.59003.e3. Epub 2005 Aug 4. PubMed PMID: 16081860. 5 Mehrholz, J., S. Thomas, C. Werner, J. Kugler, M. Pohl and B. Elsner (2017). “Electromechanical-Assisted Training for Walking after Stroke (Update).” Cochrane Database Syst Rev 5: Cd006185. 6 Mehrholz, J., M. Pohl, T. Platz, J. Kugler and B. Elsner (2018). “Electromechanical and robot-assisted arm training for improving activities of daily living, arm function, and arm muscle strength after stroke.” Cochrane Database Syst Rev 9: CD006876.
photo caption: Elizabeth Watson, PT, DPT, NCS, works with a client on gait training using a robot-assisted over-treadmill dynamic body weight support system.
by Elizabeth Watson, PT, DPT, NCS
Recovery following a neurological injury is a long, slow process and does not follow a set time frame. Recovery is about more than just walking; it is about regaining function and improving overall quality of life.
This article explores a specialized program at Magee Rehabilitation Hospital-Jefferson Health in Philadelphia called Gaining Ground. The goal of Gaining Ground is to extend Magee’s mission beyond traditional physical and cognitive therapy services and reduce the barriers to continued exercise and wellness. This article also highlights the different technologies used during this program and the impact on the quality of life of the participants.
Increased evidence supports the benefits of exercise and physical activity on the physiologic and psychosocial function of individuals following neurological injuries.1 In addition, physical inactivity following a neurological injury leads to increased vulnerability to secondary health complications, including cardiovascular disease and loss of bone density and muscle mass.1 Evidence-based physical activity guidelines have been established for the general population and those with disabilities. These guidelines highlight the importance of moderate-intensity aerobic exercise and strength training for individuals with spinal cord injuries and stroke survivors.2,3
Making Progress Accessible
Barriers to continued exercise following a neurological injury include lack of accessible fitness facilities, absence of personal assistants knowledgeable about exercise programs appropriate for those with neurological injuries, absence of specialized equipment, and fear of injury. Gaining Ground was developed to reduce these barriers.
Gaining Ground is an individualized exercise program, taking into account the goals and abilities of the client. The intensive, boot camp-style program takes place 3 days a week for 4 weeks. Clients vary in presentation from those at a power wheelchair level to ambulatory patients. Some are more recently injured, just finishing outpatient therapy and looking to be challenged further and establish a wellness program. Other clients have been injured for more than 20 years and are exploring newer technologies and treatment techniques that did not exist when they were first injured. These clients find that the program’s intense nature often encourages a continued wellness program after Gaining Ground ends.
Each day includes 4 hours of exercise. A one-on-one training session with an activity-based therapy specialist focuses on increasing cardiovascular endurance, muscle strength and flexibility, sitting or standing tolerance, and balance. Working with a physical therapist provides the opportunity to continue working toward goals not reached during traditional therapy, as well as a chance to trial different technologies and specialized equipment working toward more neurological recovery. Once a client’s program is established, he or she is set up on specialized equipment such as a locomotor device or FES cycle for an hour of activity-based exercise.
A daily group exercise class helps increase strength, improve cardiovascular endurance, and enhance overall well-being. Exercises emphasize the muscle groups of the upper extremity and core necessary to complete daily functional activities. Group sessions include a circuit using the multi-station wheelchair-accessible weight machine, a wheelchair-accessible upper extremity exerciser, a conventional weight machine, a free weight and therapy band circuit training program, and getting onto the floor to work on whole body exercises. This allows clients the opportunity to practice getting on and off the floor in a safe environment and reduce the negative association of being on the floor related to falls. The group environment fosters interaction with others working toward a common goal.
Cardiorespiratory and strength training presented in a group setting with peers provides not just physical but also emotional improvements.1,4 Depression scores and bodily pain scores decreased after participation in a group exercise program for individuals with spinal cord injuries. Past participants of Gaining Ground have commented on the motivating environment of the group sessions.
Equipment utilized during the program may include functional electrical stimulation systems, gait training devices such as the robot-assisted over-treadmill dynamic body weight support system, mobile robotic over-ground body weight support system, lower extremity robotic exoskeletons, vibration therapy plate, computerized balance system, wheelchair-accessible upper extremity exerciser, multi-station wheelchair accessible weight machine, resistance circuit trainer, rowing ergometer, recumbent trainer, and upper body ergometer. A few of the more advanced technologies are detailed below.
Body Weight Support Training
The robot-assisted over-treadmill dynamic body weight support system utilizes robotic-assisted gait training. A harness suspends the patient over a treadmill while the legs are guided through the walking pattern using a robotic orthosis. Speed, the amount of load through the legs, and the amount of guidance provided by the robotic orthosis, are all variables that can be adjusted to appropriately challenge the client. The robot-assisted over-treadmill body weight support system enables effective and intensive training promoting neuroplasticity and recovery potential.
This system can be used with various augmented performance feedback games. The level of difficulty can be chosen based on the client’s ability and therapy focus. Studies have shown that when using augmented performance feedback, muscle activation and cardiovascular exertion can be considerably increased.5 Most clients in the Gaining Ground Program utilize this device two to three times a week.
The mobile robotic over-ground body weight support system allows a therapist to work on overground balance and gait training, bridging the gap between treadmill-based activities and free walking. The system can provide body-weight support equally or asymmetrically depending on a client’s impairments. Therapists can steer this device or choose the mode that allows a patient to work on self-directed gait. Therapists can challenge the patient with various balance and functional activities by using a balance board, steps, or varied terrain within the width of the device’s frame.
Another type of equipment used for upright positioning and gait training are robotic exoskeletons designed for the lower limbs. These wearable bionic suits help patients with lower extremity weakness or paralysis to stand and walk overground using a reciprocal pattern with full weight bearing using a walker, crutches, or cane. Sensors in the device trigger a step once the patient shifts weight in the appropriate manner. Motors in the hip and knee joints power the movement in place of decreased leg function. During the Gaining Ground program, therapists use the exoskeletal devices in two ways. The robotic exoskeleton allows those with motor complete spinal cord injuries the opportunity to be upright and reap the benefits of dynamic weight bearing. These include maintenance of bone mass, improved balance and trunk activation, improved sleep, mental outlook, mood and motivation, improved bowel and bladder function with decreased incidence of UTIs, decreased pain, decreased incidence of pressure ulcers, reduction in fat mass, and increase in lean body mass.
These devices can also be used to retrain weight shifting and gait patterns of clients with incomplete spinal cord injuries, and post stroke or traumatic brain injury. As a client relearns the appropriate gait pattern, the amount of assistance provided by the motors is adjusted at each leg and each joint individually to challenge the client. Improved gait parameters and gait speed have been seen following gait retraining using exoskeletal devices with individuals who have incomplete paralysis.
Functional Electrical Stimulation
Functional electrical stimulation (FES) is used in various forms during the Gaining Ground program. Some clients are set up on the FES cycle or FES seated elliptical. Electrodes are placed on up to 12 muscles of the upper extremity, core, or lower extremities. The therapist can customize the stimulation settings to evoke the desired muscle contraction for each muscle group. The motor of the cycle provides the support necessary to complete the cycling motion in conjunction with the stimulation-producing muscle contractions for either upper extremity or lower extremity cycling.
Many patients with neurological injuries experience decreased mobility and physiological function. This more sedentary lifestyle caused by immobility contributes to secondary health complications and the chance of re-hospitalization. The benefits of the FES systems extend beyond reducing muscle atrophy and improving motor function. Studies have shown a positive therapeutic benefit affecting many health conditions including pneumonia, hypertension, heart disease, spasticity, bone density, pressure wounds, urinary tract infections, sepsis, diabetes, weight gain, depression, and quality of life.6
The task-specific integrated functional electrical stimulation systems are utilized by therapists in the Gaining Ground program to work on coordinated, dynamic movement patterns and functional skills with up to 12 channels of stimulation. Each activity has the correct sequenced stimulation pattern to perform the prescribed activity. Common programs worked on during the Gaining Ground program include seated postural correction, bridging, sit to stands, standing, and UE movement patterns. One client with a diagnosis of C4 AIS B tetraplegia demonstrated improved self-feeding and the ability to access the controls on his power wheelchair joystick versus switch options after using the forward reach and grasp program for two consecutive rounds of Gaining Ground.
Nicole suffered a T2 AIS B injury on August 18, 2018, after an auto accident. In addition to several broken vertebrae, she also suffered six broken ribs, a collapsed lung, and lacerations to her head, face, and hands. Doctors performed two surgeries on her spine, and she underwent intense respiratory therapy. Nicole attended Gaining Ground about 7 months after her injury. She “loved how it pushed [her] out of her comfort zone.” Nicole recognized the individualized nature of the program and how it could be customized to fit her goals. Nicole’s program incorporated use of the exoskeleton or the task-specific integrated FES system for postural retraining and standing during her therapy hours and the robotic over-treadmill dynamic body weight support system three times a week. The training sessions with the activity-based therapy specialist demonstrated what she could achieve independently to continue to challenge herself after the program. As a personal trainer prior to injury, Nicole found this especially valuable. Nicole demonstrated significant progress in her ability to get up and down off the floor each week and realized how important a skill this is.
Magee’s Gaining Ground Program offers clients the opportunity to improve their functional independence and emotional well-being, while setting goals for future wellness initiatives. The small group setting has proven beneficial in helping individuals achieve these goals and make new friends in the process. RM
Elizabeth Watson, PT, DPT, NCS, is clinical supervisor of the Locomotor Training Clinic at Magee Rehabilitation in Philadelphia. She also serves as adjunct professor for area physical therapy programs. In 2018, Dr Watson received the SCI Spinal Interest Group Award for Excellence. Watson earned her DPT from Temple University and is ABPTS certified in Neurologic Physical Therapy. She has presented nationally and published case studies on locomotor training. For more information, contact RehabEditor@medqor.com.
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Wearable exoskeletons have been proven to be efficacious in aiding walking for individuals suffering from lower limb mobility disorder. However, the application of most existing devices is limited to inconvenience of usage, e.g., complicated training and unnatural gait. This paper presents a novel autonomous lower extremity exoskeleton, Auto-LEE, for the purpose of improving the practicality of walking assistive devices as well as simplifying their application process. The developed exoskeleton consists of two robotic legs, and each of them has 5 active degrees-of-freedom (DOFs) to independently control the rotations of hip, knee and ankle joints in the sagittal and coronal planes, which enables the device to possess self-balancing ability and flexible gait. The modular design concept is introduced into the structure and hardware development of Auto-LEE, making it more convenient to be assembled and maintained. In order to validate the self-balancing walking ability, virtual prototype simulation and preliminary experiment on flat terrain are implemented.
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Purpose: To assess the effects of lower limb robotic exoskeletons on outcomes in the rehabilitation of people with acquired brain injury.
Materials and methods: A systematic review of seven electronic databases was conducted. The primary outcome of interest was neuromuscular function. Secondary outcomes included quality of life, mood, acceptability and safety. Studies were assessed for methodological quality and recommendations were made using the GRADE system.
Results: Of 2469 identified studies, 13 (n = 322) were included in the review. Five contained data suitable for meta-analysis. When the data were pooled, there were no differences between exoskeleton and control for 6-Minute Walk Test, Timed Up and Go or 10-Meter Walk Test. Berg Balance Scale outcomes were significantly better in controls (MD = 2.74, CI = 1.12–4.36, p = 0.0009). There were no severe adverse events but drop-outs were 11.5% (n = 37). No studies reported the effect of robotic therapy on quality of life or mood. Methodological quality was on average fair (15.6/27 on Downs and Black Scale).
Conclusions: Only small numbers of people with acquired brain injury had data suitable for analysis. The available data suggests no more benefit for gait or balance with robotic therapy than conventional therapy. However, some important outcomes have not been studied and further well-conducted research is needed to determine whether such devices offer benefit over conventional therapy, in particular subgroups of those with acquired brain injury.
Implications for Rehabilitation
There is adequate evidence to recommend that powered over-ground lower limb robotic exoskeletons should not be used clinically in those with ABI, and that use should be restricted to research.
Further research (controlled trials) with dependent ambulators is recommended.
Research of other outcomes such as acceptability, spasticity, sitting posture, cardiorespiratory and psychological function, should be considered.
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Exoskeleton robots have been demonstrated to effectively assist the rehabilitation of patients with upper or lower limb disabilities. To make exoskeletons more accessible to patients, they need to be lightweight and compact without major performance tradeoffs. Existing upper-limb exoskeletons focus on assistance with coarse-motion of the upper arm while forearm fine-motion rehabilitation is often ignored. This paper presents an elbow-wrist exoskeleton with five degrees-of-freedom (DoFs). Using geared bearings, slider crank mechanisms, and a spherical mechanism for the wrist and elbow modules, this exoskeleton can provide 5-DoF rotary motion forearm assistance. The optimized exoskeleton dimensions allow sufficient rotation output while the motors are placed parallel to the forearm and elbow joint. Thus compactness and less inertia loading can be achieved. Linear and rotary series elastic actuators (SEAs) with high torque-to-weight ratios are proposed to accurately measure and control interaction force and impedance between exoskeleton and forearm. The resulting 3-kg exoskeleton can be used alone or easily in combination with other exoskeleton robots to provide various robot-aided upper limb rehabilitation.
The purpose of this paper is to propose a variable impedance control method of finger exoskeleton for hand rehabilitation using the contact forces between the finger and the exoskeleton, making the output trajectory of finger exoskeleton comply with the natural flexion-extension (NFE) trajectory accurately and adaptively.
This paper presents a variable impedance control method based on fuzzy neural network (FNN). The impedance control system sets the contact forces and joint angles collected by sensors as input. Then it uses the offline-trained FNN system to acquire the impedance parameters in real time, thus realizing tracking the NFE trajectory. K-means clustering method is applied to construct FNN, which can obtain the number of fuzzy rules automatically.
The results of simulations and experiments both show that the finger exoskeleton has an accurate output trajectory and an adaptive performance on three subjects with different physiological parameters. The variable impedance control system can drive the finger exoskeleton to comply with the NFE trajectory accurately and adaptively using the continuously changing contact forces.
The finger is regarded as a part of the control system to get the contact forces between finger and exoskeleton, and the impedance parameters can be updated in real time to make the output trajectory comply with the NFE trajectory accurately and adaptively during the rehabilitation.
Movement impairments resulting from neurologic injuries, such as stroke, can be treated with robotic exoskeletons that assist with movement retraining. Exoskeleton designs benefit from low impedance and accurate torque control. We designed a two-degrees-of-freedom tethered exoskeleton that can provide independent torque control on elbow flexion/extension and forearm supination/pronation. Two identical series elastic actuators (SEAs) are used to actuate the exoskeleton. The two SEAs are coupled through a novel cable-driven differential. The exoskeleton is compact and lightweight, with a mass of 0.9 kg. Applied rms torque errors were less than 0.19 Nm. Benchtop tests demonstrated a torque rise time of approximately 0.1 s, a torque control bandwidth of 3.7 Hz, and an impedance of less than 0.03 Nm/° at 1 Hz. The controller can simulate a stable maximum wall stiffness of 0.45 Nm/°. The overall performance is adequate for robotic therapy applications and the novelty of the design is discussed.
According to the present situation that the treatment means for apoplectic patients is lagging and weak, a set of long-distance exoskeleton rehabilitation training system with 5 DOF for upper limb was developed. First, the mechanical structure and control system of the training system were designed. Then a new kind of building method for virtual environment was proposed. The method created a complex model effectively with good portability. The new building method was used to design the virtual training scenes for patients’ rehabilitation in which the virtual human model can move following the trainer on real time, which can reflect the movement condition of arm of patient factually and increase the interest of rehabilitation training. Finally, the network communication technology was applied into the training system to realize the remote communication between the client-side of doctor and training system of patient, which makes it possible to product rehabilitation training at home.
A key approach for reducing motor impairment and regaining independence after spinal cord injuries or strokes is frequent and repetitive functional training. A compatible exoskeleton (Co-Exos II) is proposed for the upper-limb rehabilitation. A compatible configuration was selected according to optimum configuration principles. Four passive translational joints were introduced into the connecting interfaces to adapt the glenohumeral joint (GH) movements and improve the compatibility of the exoskeleton. This configuration of the passive joints could reduce the influence of gravity of the exoskeleton device and the upper extremities. A Co-Exos II prototype was developed and still owned a compact volume. A new approach was presented to compensate the vertical GH movements. The shoulder closed-loop was simplified as a guide-bar mechanism. The compatible models of this loop were established based on the kinematic model of GH. The compatible experiments were completed to verify the kinematic models and analyze the human-machine compatibility of Co-Exos II. The theoretical displacements of the translational joints were calculated by the kinematic model of the shoulder loop. The passive joints exhibited good compensations for the GH movements through comparing the theoretical and measured results, especially vertical GH movements. Co-Exos II showed good human-machine compatibility for upper limbs.
Research efforts in neurorehabilitation technologies have been directed towards creating robotic exoskeletons to restore motor function in impaired individuals. However, despite advances in mechatronics and bioelectrical signal processing, current robotic exoskeletons have had only modest clinical impact. A major limitation is the inability to enable exoskeleton voluntary control in neurologically impaired individuals. This hinders the possibility of optimally inducing the activity-driven neuroplastic changes that are required for recovery.
We have developed a patient-specific computational model of the human musculoskeletal system controlled via neural surrogates, i.e., electromyography-derived neural activations to muscles. The electromyography-driven musculoskeletal model was synthesized into a human-machine interface (HMI) that enabled poststroke and incomplete spinal cord injury patients to voluntarily control multiple joints in a multifunctional robotic exoskeleton in real time.
We demonstrated patients’ control accuracy across a wide range of lower-extremity motor tasks. Remarkably, an increased level of exoskeleton assistance always resulted in a reduction in both amplitude and variability in muscle activations as well as in the mechanical moments required to perform a motor task. Since small discrepancies in onset time between human limb movement and that of the parallel exoskeleton would potentially increase human neuromuscular effort, these results demonstrate that the developed HMI precisely synchronizes the device actuation with residual voluntary muscle contraction capacity in neurologically impaired patients.
Continuous voluntary control of robotic exoskeletons (i.e. event-free and task-independent) has never been demonstrated before in populations with paretic and spastic-like muscle activity, such as those investigated in this study. Our proposed methodology may open new avenues for harnessing residual neuromuscular function in neurologically impaired individuals via symbiotic wearable robots.
The ability to walk directly relates to quality of life. Neurological lesions such as those underlying stroke and spinal cord injury (SCI) often result in severe motor impairments (i.e., paresis, spasticity, abnormal joint couplings) that compromise an individual’s motor capacity and health throughout the life span. For several decades, scientific effort in rehabilitation robotics has been directed towards exoskeletons that can help enhance motor capacity in neurologically impaired individuals. However, despite advances in mechatronics and bioelectrical signal processing, current robotic exoskeletons have had limited performance when tested in healthy individuals  and have achieved only modest clinical impact in neurologically impaired patients , e.g., stroke [3, 4], SCI patients . […]
Fig. 1 Enter aSchematic representation of the real-time modeling framework and its communication with the robotic exoskeleton. The whole framework is operated by a Raspberry Pi 3 single-board computer. The framework consists of five main components: a The EMG plugin collects muscle bioelectric signals from wearable active electrodes and transfers them to the EMG-driven model. b The B-spline component computes musculotendon length (Lmt) and moment arm (MA) values from joint angles collected via robotic exoskeleton sensors. c The EMG-driven model uses input EMG, Lmt and MA data to compute the resulting mechanical forces in 12 lower-extremity musculotendon units (Table 1) and joint moment about the degrees of freedom of knee flexion-extension and ankle plantar-dorsiflexion. d The offline calibration procedure identifies internal parameters of the model that vary non-linearly across individuals. These include optimal fiber length and tendon slack length, muscle maximal isometric force, and excitation-to-activation shape factors. eThe exoskeleton plugin converts EMG-driven model-based joint moment estimates into exoskeleton control commands. Please refer to the Methods section for an in-depth description caption