Neuromuscular electrical stimulation and dynamic bracing as a treatment for upper-extremity spasticity in children with cerebral palsy

Active, Actuated, and Assistive: a Scoping Review of Exoskeletons for the Hands and Wrists

BACKGROUND

Assistive technology is often incorporated into rehabilitation and support for those impacted by upper limb impairments. When powered, these devices provide additional force to the joints of users with muscle weakness. Actuated devices allow dynamic movement compared to splints, therefore improving the ability to complete activities of daily living. However, these devices are not often prescribed and are underrepresented in research and clinical settings.

OBJECTIVE

This review examined the existing literature on devices developed to support hand and wrist functionality in daily activities. Focusing on active, powered, and actuated devices, to gain a clearer understanding of the current limitations in their design and prescription.

METHODOLOGY

The scoping review was conducted using the PRISMA-ScR guidelines. A systematic search was done on MEDLINE, EMBASE, Scopus, Web of Science, and NHS the Knowledge Network from inception to May 2023. Articles were included if the device was portable; supported the hands and wrist actively using an actuator; and could be used for assistive living during or post-rehabilitation period.

FINDINGS

A total of 135 studies were included in the analysis of which 34 were clinical trials. The design and control methods of 121 devices were analyzed. Electrical stimulation and direct mechanical transmission were popular actuation methods. Electromyography (EMG) and joint movement detection were highly used control methods to translate user intentions to device actuation. A total of 226 validation methods were reported, of which 44% were clinically validated. Studies were often not conducted in operational environments with 69% at technology readiness levels ≤ 6, indicating that further development and testing is required.

CONCLUSION

The existing literature on hand and wrist exoskeletons presents large variations in validation methods and technical requirements for user-specific characteristics. This suggests a need for well-defined testing protocols and refined reporting of device designs. This would improve the significance of clinical outcomes and new assistive technology.

Immediate effects of a novel hand rehabilitation board on fine motor skills in children with cerebral palsy: A pilot study

BACKGROUND

In children with cerebral palsy (CP), fine motor skills limit forearm supination and active extension of the elbow, wrist, or fingers. Therapeutic interventions focusing on improving the ranges at these joints while facilitating active movements are the key to augmenting fine motor skills.

OBJECTIVE

This pilot study examines if children with CP (with UE involvement) exposed to the Novel Hand Rehabilitation (NHR) Board will demonstrate 1) changes in spasticity and passive ROM of forearm and wrist/finger muscles, and 2) improvement in fine motor abilities.

METHODS

The forearm and wrist/fingers of children with spastic CP (N = 15; M = 7, F = 8) aged 49-72 months (65.33±6.355 months) were positioned on the NHR board till their tolerance limit or a minimum duration of 30 minutes. The outcome measures, i.e., spasticity (Modified Ashworth Scale), passive range of motion (PROM) of wrist and fingers, and fine motor skills (PDMS-2 - Fine motor scale), were recorded.

RESULTS

The spasticity of forearm pronators (0.001) and wrist flexors (0.008) reduced significantly, but not in wrist extensors. Post-intervention improvements in wrist extension (p = 0.005) and ulnar deviation ROM (p = 0.007) were significant. In thumb, changes were non-significant for the CMC flexion, but extension (0.003) and abduction (0.001) as well as MCP extension (0.004) were significant. The post-intervention MCP extension ROM for the 2nd (0.001), 3rd (0.007), and 4th fingers (0.014) were also substantial, but not for PIP and DIP joints. The post-intervention percentage change in the Grasping and Visual-motor integration subtests of PDMS-2 was 11.03% (p = 0.002) and 5.09% (p = 0.001) respectively.

CONCLUSION

The immediate effects on fine motor skills in children with CP after the NHR board application were positive and encouraging. Hence, the NHR board can be recommended as an intervention to improve the fine motor abilities of children with CP.

Neuromuscular Electrical Stimulation of Upper Limbs in Patients With Cerebral Palsy: A Systematic Review and Meta-analysis of Randomized Controlled Trials

OBJECTIVE

The aim of the study is to assess the effects of neuromuscular electrical stimulation on the upper limbs of patients with cerebral palsy.

DESIGN

We searched PubMed, Cochrane, Embase, and Scopus databases for randomized controlled trials examining the effects of neuromuscular electrical stimulation on the upper limbs of children with cerebral palsy.

RESULTS

Eight randomized controlled trials ( N = 294) were included in the meta-analysis. Compared with traditional physical therapy, sensorimotor training and task-oriented training, constraint-induced movement therapy, dynamic bracing, and conventional robot-assisted therapy, neuromuscular electrical stimulation in combination with these therapies resulted in significantly greater functional scale scores (standardized mean difference = 0.80; 95% confidence interval = 0.54 to 1.06), muscle strength of upper limbs (standardized mean difference = 0.57; 95% confidence interval = 0.25 to 0.88), and spasticity of upper limbs (relative risk = 2.53; 95% confidence interval = 1.46 to 4.39; standardized mean difference = -0.18; 95% confidence interval = -0.29 to -0.06) but did not improve the wrist range of motion (standardized mean difference = 0.43; 95% confidence interval = -0.04 to 0.91). In addition, the effect of neuromuscular electrical stimulation on functional scale scores remained after 3-mo follow-up (standardized mean difference = 0.68; 95% confidence interval = 0.16 to 1.2).

CONCLUSIONS

Neuromuscular electrical stimulation effectively improved hand function, muscle strength, and spasticity in patients with cerebral palsy.

Fully Immersive Virtual Reality Game-Based Training for an Adolescent with Spastic Diplegic Cerebral Palsy: A Case Report

BACKGROUND

Recently, virtual reality-based training (VR-based training) is receiving attention as greater emphasis is placed on the importance of interest and motivation in participation. However, studies investigating the effects of fully immersive VR-based training are insufficient.

CASE PRESENTATION

We report a case of using a fully immersive VR game-based training in a patient with cerebral palsy. A 15-year-old girl was diagnosed with spastic diplegia cerebral palsy Gross Motor Function Classification System level II. A six-week intervention (18 sessions) phase was performed with one fully immersive VR game using PlayStation^®VR in three sessions per week. After 18 sessions of training, the scores on the gross motor function measure-88 (Gross Motor Function Measure-88-GMFM-88), pediatric balance scale (PBS), timed up and go test (TUG), functional gait assessment (FGA), and 10 m walking test (10MWT) were improved: GMFM-88, 91.56 points (9.31 points increase); PBS, 45 points (6 points increase); TUG, 8.23 s (6.9 s decrease); FGA, 11 points (3 points increase); the 10 MWT, 5.27 s (6.59 s decrease).

CONCLUSIONS

This study found that a fully immersive VR game-based training using PlayStation^®VR may be an effective intervention for GMFCS level II adolescent, leading to some improvement of motor function, balance and gait skills in adolescents with cerebral palsy.

Neuromuscular Electrical Stimulation Improves Muscle Strength, Biomechanics of Movement, and Functional Mobility in Children With Chronic Neurological Disorders: A Systematic Review and Meta-Analysis

OBJECTIVE

Chronic neurological disorders (CNDs) generally produce deleterious effects on the musculoskeletal system and can affect physical activity and increase sedentary behavior in children, hindering the execution of training programs and the attainment of a correct dose of exercise. The purpose of this systematic review was to analyze the effect of neuromuscular electrical stimulation (NMES) on skeletal muscle and then on biomechanics of movement, functional mobility, strength, spasticity, muscle architecture, and body composition of children and adolescents with CNDs and chronic diseases.

METHODS

The search was conducted in April 2020 in PubMed, MEDLINE, Scopus, the Cochrane Library, and Web of Science, without publication period restriction. Publications investigating the effect of NMES on children and adolescents with CNDs and other chronic diseases were independently selected by 2 researchers. One author independently extracted data from the studies selected, and a second author cross-checked.

RESULTS

Eighteen studies with 595 participants aged between 3 and 14 years were included. Quality assessment showed that 50% of the studies presented a low risk of bias. The pooled effect of NMES on gross motor functional measure, calculated as a standardized mean difference using a random effects model, was 0.41 (95% CI = 0.19-0.64).

CONCLUSION

The use of NMES programs for children diagnosed with cerebral palsy, spinal muscular atrophy, and obstetric injury of the brachial plexus was effective in improving muscle strength, biomechanics of movement, and functional mobility.

IMPACT

NMES can be a useful tool to prevent the reduction of mobility that results from CNDs.

Perinatal stroke: mapping and modulating developmental plasticity

Most cases of hemiparetic cerebral palsy are caused by perinatal stroke, resulting in lifelong disability for millions of people. However, our understanding of how the motor system develops following such early unilateral brain injury is increasing. Tools such as neuroimaging and brain stimulation are generating informed maps of the unique motor networks that emerge following perinatal stroke. As a focal injury of defined timing in an otherwise healthy brain, perinatal stroke represents an ideal human model of developmental plasticity. Here, we provide an introduction to perinatal stroke epidemiology and outcomes, before reviewing models of developmental plasticity after perinatal stroke. We then examine existing therapeutic approaches, including constraint, bimanual and other occupational therapies, and their potential synergy with non-invasive neurostimulation. We end by discussing the promise of exciting new therapies, including novel neurostimulation, brain-computer interfaces and robotics, all focused on improving outcomes after perinatal stroke.

Rationale for prescription, and effectiveness of, upper limb orthotic intervention for children with cerebral palsy: a systematic review

PURPOSE

To explore (i) reasons for upper limb orthosis prescription for children with cerebral palsy (CP), (ii) the link between reason and effect according to intended outcome and outcome measure utilized and (iii) to classify the prescribed orthoses using standard terminology.

METHOD

A prospectively registered (center for reviews and dissemination: 42015022067) systematic review searched for experimental and observational studies investigating rigid/thermoplastic upper limb orthotic intervention for children aged 0-18 with CP. The Cochrane central register, MEDLINE, CINAHL, Embase, SCOPUS and Web of Science databases were searched. Included studies were assessed for risk of bias.

RESULTS

Sixteen studies met selection criteria. Two studies described a specific reason for orthosis prescription, six prescribed orthoses to manage a clinical symptom and eight did not describe a reason. Eight studies were analyzed for effect according to intended outcome with no clear connection found between reasons for prescription, outcome measures utilized and effect reported.

INTERPRETATION

The lack of evidence for upper limb orthotic intervention for children with CP leads to uncertainty when considering this treatment modality. Future research is needed to evaluate the effect of orthosis wear in relation to intended outcome utilizing robust methods and valid and reliable outcome measures. Implications for rehabilitation: Insufficient evidence exists about the reason for prescription of upper limb orthoses. The connection between reason for orthosis prescription, intended outcome, outcome measure utilized and observed effect is unclear. Recommend orthosis prescription to be accompanied by clear documentation of the aim of the orthosis and description using orthosis classification system terminology. Outcome measures consistent with the reason for orthosis prescription and intended outcome of the intervention are essential to measure effectiveness of the intervention.

Effects of neuromuscular electrical stimulation on the wrist and finger flexor spasticity and hand functions in cerebral palsy

PURPOSE

To evaluate the effects of neuromuscular electrical stimulation on wrist range of motion, wrist and finger flexor spasticity, and hand functions in patients with unilateral cerebral palsy.

METHOD

Twenty-four children with unilateral spastic cerebral palsy (14 boys and 10 girls) between the ages of 5 and 14 years were randomized into neuromuscular electrical stimulation and control groups. Conventional exercises were applied, and static volar wrist-hand orthosis was administered to all patients 5 days a week for 6 weeks. Additionally, 30-minute neuromuscular electrical stimulation sessions were applied to the wrist extensor muscles in the neuromuscular electrical stimulation group. Patients were evaluated by Zancolli Classification System, Manual Ability Classification System, and Abilhand-Kids Test.

RESULTS

Compared with baseline, a significant increase was evident in active wrist extension angle at the fourth and sixth weeks in both groups (all P < 0.001), more prominent in the neuromuscular electrical stimulation group at the fourth and sixth weeks (P = 0.015 and P = 0.006, respectively). A decrease was observed in the spasticity values in the neuromuscular electrical stimulation group at the fourth and sixth weeks (P = 0.002 and P = 0.001, respectively) and in the control group only at the sixth week (P = 0.008). Abilhand-Kids values improved only in the neuromuscular electrical stimulation group (P < 0.001).

CONCLUSION

Neuromuscular electrical stimulation application in addition to conventional treatments is effective in improving active wrist range of motion, spasticity, and hand functions in cerebral palsy.

Functional electrical stimulation for equine epaxial muscle spasms: retrospective study of 241 clinical cases

A retrospective study of 241 clinical cases, utilising over 1,800 functional electrical stimulation (FES) treatments to alleviate epaxial muscle spasms, showed that almost 80% (191) of the horses had a 1-grade improvement in muscle spasms after 2 FES treatments, based on the Modified Ashworth Scale adapted to horses. In addition, 60% (142) of these horses showed a sustained improvement for a minimum of 2 months.

Short-term and long-term effects of electrical stimulation on skin properties

BACKGROUND

Electrical stimulation (ES) has been used in treating different medical conditions; however, not much is known about the effect of this application on skin properties. The purpose of this study was to investigate the short-term and long-term effects of ES on biophysical properties of the skin.

METHODS

A pretest-posttest control design was used in the study. Thirteen men (N = 13, age (M ± SD), 19 ± 5.6 years) were free of skin abnormality on the volar aspect of both forearms. Four areas were allocated and marked with a layout template of two circles 2 cm in diameter and 2 cm apart. Areas 1 and 2 were allocated on the experimental forearm and area 3 and 4 on the control forearm. ES was applied for 15 minutes with two rubber electrodes 8 cm apart surrounding areas 1 and 2 on the experimental forearm three times a week for 2 weeks. Skin properties including transepidermal water loss (TEWL), melanin content, erythema, elasticity and pH were measured pre-ES, during ES and post-ES, and after 2 weeks of applying ES to find out the short-term and long-term effects on skin.

RESULTS

The TEWL was increased during ES at 7, 15 and 15-minutes post-ES compared with the baseline (p < 0.01) and to the control forearm (p = 0.04) measurements, and no increase have been noticed of TEWL on the control forearm (p = 0.11). Also, we found no difference in the other skin properties (p > 0.05) on both forearms, and there were no long-term effects (p > 0.05) in any tested variable.

CONCLUSION

Electrical stimulation caused temporary increase in TEWL with no effects on other skin properties.

The combined effect of Dynamic splinting and Neuromuscular electrical stimulation in reducing wrist and elbow contractures in six children with Cerebral palsy

The aim of this pilot study was to investigate the feasibility of applying the combination of Dynamic splinting (DS) and Neuromuscular electrical stimulation (NMES) in order to improve wrist and elbow function, and range of motion, in children with upper limb contractures due to Cerebral palsy (CP). Six children aged seven to 16, with contractures at the wrist or elbow, were recruited. Following a 12-week baseline period all participants underwent a 12-week treatment period where DS was used for one hour per day and combined with NMES for the second half of the 1-h treatment. A 12-week follow-up period then ensued. Upper limb function was assessed with the Melbourne assessment, physical disability with the Paediatric Evaluation of Disability Index and the Activity Scale for Kids, and quality of life with the Pediatric Quality of Life Scale. Passive and active range of motion at the wrist and elbow were measured using manual and electrical goniometers. The technique of using combined NMES and DS was demonstrated to be feasible and compliance with the intervention was good. There was an increase in passive elbow extension in two participants treated for elbow contractures, although no accompanying change in upper limb function was demonstrated. Wrist range of movement improved in one participant treated for wrist contracture.

Review of electrical stimulation in cerebral palsy and recommendations for future directions

Electrical stimulation (ES) for treatment of neuromuscular disorders is introduced. Various forms of ES are defined. Characteristics of cerebral palsy (CP) and treatment options are given. The clinical objectives of ES for CP treatment are stated. A review of the literature for treatment in CP is given. Several common themes within the literature and limitations in prior studies are explored. The majority of studies have used surface stimulation, which has several inherent limitations. To address these limitations, implanted devices may be used. Implanted device systems include percutaneous stimulation systems, and fully implantable leaded systems. While both of these technologies have advantages over surface stimulation, they also have their own limitations. To further address the limitations of percutaneous and fully implantable leaded systems, the Alfred Mann Foundation has developed a completely implantable, telemetered device known as the Radio Frequency Microstimulator (RFM). Results from a study using the RFM for arm rehabilitation in poststroke patients are given. A list of desirable design features for an ES system for CP is given. The next generation microstimulator device under development at the Alfred Mann Foundation is presented. This device may well serve the needs for ES in CP.

A simple device to assess and train motor coordination

PURPOSE

The purpose of this project was to develop a computer program which can be used on a laptop or other IBM-based computer to assess and train motor coordination in children with closed head trauma or cerebral palsy.

APPARATUS

Muscle coordination was assessed by the child's ability to track a series of lines of increasing complexity. A stylus was used by the child to trace lines on a computer screen. Two different line tests were used. In the first, lines of various complexities were drawn on the screen at various angles. The child was asked to trace the line and the accuracy with which the line was traced was determined, providing a score. In a second test, a line was drawn on the screen and the child was asked to trace the line as it was drawn. The error in tracking the line and the time to track the line both were used to evaluate and score the child's performance. Finally, a 'Winnie the Pooh' character was flashed on the screen with distracters such as trees and other animals, and the child was asked to touch the Pooh. By increasing the speed of movement and decreasing the duration that the characters appeared on the screen, the child could be challenged. Successful touching of a character resulted in a positive score.

EXPERIMENTAL TESTING

Six children with cerebral palsy were compared to five children who did not have cerebral palsy, to evaluate the device. While both groups of children showed an increase in motor skills using the program, the increase seen in the children with cerebral palsy was 5-fold greater than that of the control group.

CONCLUSIONS

While only a few children were tested with the device, the device seems to prove quite useful for physical and occupational therapy for working on motor skills in children. More investigation is warranted.

Effects of surface electrical stimulation on the muscle–tendon junction of spastic gastrocnemius in stroke patients

PURPOSE

The purpose of this study was to explore the effects of spasticity suppression by surface electrical stimulation (ES) o the muscle-tendon junction of spastic gastrocnemius muscles in stroke.

METHODS

Twenty-four neurologically stable stroke patients (aged 41-69 years, 12-35 months post-stroke), with spasticity graded 2 or 3 on the modified Ashworth scale, were recruited and divided into two groups. In the ES group, each patient received 20 min of surface ES once daily, 6 days per week for 1 month. In the control groups, ES was used with stimulation intensity kept at zero. To evaluate the therapeutic effect, the modified Ashworth scale, Fmax/Mmax ratio, H-reflex latency, H-reflex recovery curve, and the 10-m walking time were tested before and after the 1-month of treatment.

RESULTS

In the ES group, the modified Ashworth scale showed a trend toward reduced spasticity after 1 month of treatment. The Fmax/Mmax ratio decreased from 8.10% +/- 4.84% to 4.00% +/- 1.36%; the H-reflex latency increased from 28.87 +/- 2.45 ms to 29.40 +/- 2.57 ms; the H-reflex recovery curves indicated a downward shift; and the 10-metre walking time significantly decreased after ES. In the control group, none of the measures showed a statistically significant change.

CONCLUSIONS

In this study, we demonstrated a way to suppress spasticity at a metameric site and to increase walking speed effectively by applying surface ES on the muscle-tendon junction of spastic gastrocnemius muscles.

Therapeutic effects of electrical stimulation on manual function of children with cerebral palsy: Evaluation of two cases

PURPOSE

To investigate changes in hand function associated with electrical stimulation for children with hemiplegic cerebral palsy.

METHOD

An ABCA single-subject design, replicated in two children, was used in this study. Each baseline (phase A) lasted 4 weeks. Intervention consisted of electrical stimulation of wrist extensors (phase B) and of wrist extensors and flexors (phase C) for 15 minutes three times a week. Intervention phases also lasted 4 weeks. Active wrist extension range of movement and three timed manual tasks were tested two times a week every week. Data analysis included the Celeration Line and Two Standard Deviation Band methods in addition to visual analysis.

RESULTS

Significant performance gains were observed for both children, especially in phase C, when both extensors and flexors were stimulated. After intervention withdrawal, significant performance decreases were observed on most analysed variables.

CONCLUSIONS

The observed performance changes seem to be associated with the presence of intervention and suggest that electrical stimulation can be a useful adjunct to improve hand function of children with cerebral palsy.

Does electrical stimulation reduce spasticity after stroke? A randomized controlled study

OBJECTIVE

To investigate the therapeutic effect of electrical stimulation on plantarflexor spasticity in stroke patients.

DESIGN

A randomized controlled clinical trial study.

SETTING

Rehabilitation clinic of Semnan University of Medical Sciences.

SUBJECTS

Forty stroke patients (aged from 42 to 65 years) with ankle plantarflexor spasticity.

INTERVENTION

Fifteen minutes of inhibitory Bobath techniques were applied to one experimental group and a combination of 9 minutes of electrical stimulation on the dorsiflexor muscles and inhibitory Bobath techniques was applied to another group for 20 sessions daily.

MAIN MEASURES

Passive ankle joint dorsiflexion range of motion, dorsiflexion strength test, plantarflexor muscle tone by Modified Ashworth Scale and soleus muscle H-reflex.

RESULTS

The mean change of passive ankle joint dorsiflexion in the combination therapy group was 11.4 (SD 4.79) degrees versus 6.1 (SD 3.09) degrees, which was significantly higher (P = 0.001). The mean change of plantarflexor muscle tonicity measured by the Modified Ashworth Scale in the combination therapy group was -1.6 (SD 0.5) versus -1.1 (SD 0.31) in the Bobath group (P = 0.001). Dorsiflexor muscle strength was also increased significantly (P = 0.04) in the combination therapy group (0.7 +/- 0.37) compared with the Bobath group (0.4 +/- 0.23). However, no significant change in the amplitude of H-reflex was found between combination therapy (-0.41 +/- 0.29) and Bobath (-0.3 +/- 0.28) groups.

CONCLUSION

Therapy combining Bobath inhibitory technique and electrical stimulation may help to reduce spasticity effectively in stroke patients.

Estimation of the distribution of intramuscular current during electrical stimulation of the quadriceps muscle

Electrical stimulation is commonly used for strengthening muscle but little evidence exists as to the optimal electrode size, waveform, or frequency to apply. Three male and three female subjects (22-40 years old) were examined during electrical stimulation of the quadriceps muscle. Two self adhesive electrode sizes were examined, 2 cm x 2 cm and 2 cm x 4 cm. Electrical stimulation was applied with square and sine waveforms, currents of 5, 10 and 15 mA, and pulse widths of 100-500 micros above the quadriceps muscle. Frequencies of stimulation were 20, 30, and 50 Hz. Current on the skin above the quadriceps muscle was measured with surface electrodes at five positions and at three positions with needle electrodes in the same muscle. Altering pulse width in the range of 100-500 micros, the frequency over a range of 20-50 Hz, or current from 5 to 15 mA had no effect on current dispersion either in the skin or within muscle. In contrast, the distance separating the electrodes caused large changes in current dispersion on the skin or into muscle. The most significant finding in the present investigation was that, while on the surface of the skin current dispersion was not different between sine and square wave stimulation, significantly more current was transferred deep in the muscle with sine versus square wave stimulation. The use of sine wave stimulation with electrode separation distances of less then 15 cm is recommended for electrical stimulation with a sine wave to achieve deep muscle stimulation.

Improving selected hand functions using a noninvasive neuroprosthesis in persons with chronic stroke

BACKGROUND AND PURPOSE

Loss of upper extremity function following stroke remains a major rehabilitation challenge. The purpose of this investigation was to determine whether the Handmaster system (NESS Ltd., Ra'anana, Israel) could improve selected hand functions in persons with chronic upper extremity paresis following stroke.

METHODS

Twenty-nine poststroke subjects consented to participate in a home-based, 3-week, nonrandomized case series trial. Main outcome measures included 3 activities of daily living (ADL) tasks: (1) lifting a 2-handled pot, (2) holding a bag while standing with a cane, and (3) a subject-selected-ADL. Secondary outcomes included lifting a 600-g weight, grip strength, electrically induced finger motion, Fugl-Meyer spherical grasp, and perceived pain scale.

RESULTS

Comparing baseline to study end point with the neuroprosthesis, the percent of successful trials with lifting the pot, weight, and bag (0% v 93%, 14% v 100%, and 17% v 93%, respectively) increased significantly. All subjects performed successfully their selected ADL and improved their Fugl-Meyer scores using the neuroprosthesis. Grip strength (6.4 +/- 7.3N v 17.7 +/- 6.2N) and active finger motion (0.5 +/- 1.2 cm v 8.4 +/- 2.6 cm) also improved with the neuroprosthesis. Pain scores significantly decreased in subjects reporting pain at baseline. Responses to questionnaire were favorable regarding the utility and therapeutic benefits of the device.

CONCLUSIONS

We conclude that the Handmaster is a safe and effective noninvasive neuroprosthesis for improving the studied hand functions and impairments in selected persons with chronic hemiplegia secondary to stroke.

Cerebral palsy: new approaches to therapy

Cerebral palsy is the most common developmental disorder causing a physical disability arising from an injury to the central nervous system. The majority of pediatric neurologists remain minimally involved in the rehabilitation of these children. Recent advances in basic and clinical neuroscience give hope that effective rehabilitation strategies, based on motor learning science, can be developed for these children. The aim of this review is to alert pediatric neurologists to these advances.

The BION devices: injectable interfaces with peripheral nerves and muscles

Object

The purpose of this study was to describe a novel technology for implantable neuromuscular stimulation to treat complications of paralysis and disuse atrophy, including shoulder subluxation, hand contractures, drop foot, and osteoarthritis. The authors review the results so far of several pilot clinical studies of these muscle stimulation devices.

Methods

Miniature wireless stimulators received power and individually addressed command signals from an external radiofrequency transmission coil. One or more implants were injected through a 12-gauge hypodermic insertion tool into muscles or adjacent to motor nerves, where they provided the means to activate the muscles in any desired pattern of intensity and frequency. Randomized controlled studies in small numbers of patients are underway to identify efficacy, acceptability, best methods of practice, and any design changes that may be required to improve the technology.

Fifty patients have been enrolled in five studies; 35 patients have undergone implantation of a total of 79 BION1 devices. Comparisons with surface stimulation in patients who have suffered a stroke with shoulder subluxation and hand contractures show similar improvements in objective measures of efficacy but higher comfort levels for stimulation by implants.

Conclusions

Injected microstimulators represent a promising new class of technology for the rehabilitation of patients with upper motor neuropathies. As the technology evolves, practitioners may be able to use it to facilitate functional reanimation of paralyzed limbs.

Effects of neuromuscular electrical stimulation treatment of cerebral palsy on potential impairment mechanisms: a pilot study

PURPOSE

This pilot study examined the effects of neuromuscular electrical stimulation (NMES) therapy on upper limb impairment in children with cerebral palsy, specifically addressing spasticity, heightened passive resistance to wrist rotation, coactivation, and weakness.

METHODS

Eight subjects, aged five to 15 years, with spastic hemiparesis subsequent to brain injury, participated in three months of NMES therapy, targeting the wrist flexor and extensor muscles. Maximum voluntary wrist extension range of motion against gravity, spasticity, passive torque, maximum voluntary isometric torque, and coactivation were recorded prior to, during, and at the conclusion of the therapy.

RESULTS

Seven of the eight subjects demonstrated a significant (>15 degrees) improvement in wrist extension range of motion against gravity following the NMES treatment, with an average gain of 38 degrees. Differences in spasticity (0.01 +/- 0.14 N-m, p = 0.80) and passive torque (0.03 +/- 0.11 N-m, p = 0.52) were not significant for these subjects. Isometric wrist extension torque, however, did increase significantly (p < 0.01), accompanied by a reduction in flexor coactivation (p < 0.01).

CONCLUSIONS

Evidence suggests that the NMES treatment protocol affected wrist extension by improving the strength of the wrist extensor muscles, possibly through decreased flexor coactivation. Further studies are required, however, to determine whether electrical stimulation itself or other facets of the therapy paradigm played the key role in improvement.

Cerebral palsy

Cerebral palsy, a range of non-progressive syndromes of posture and motor impairment, is a common cause of disability in childhood. The disorder results from various insults to different areas within the developing nervous system, which partly explains the variability of clinical findings. Management options include physiotherapy, occupational and speech therapy, orthotics, device-assisted modalities, pharmacological intervention, and orthopaedic and neurosurgical procedures. Since 1980, modification of spasticity by means of orally administered drugs, intramuscular chemodenervation agents (alcohol, phenol, botulinum toxin A), intrathecally administered drugs (baclofen), and surgery (neurectomy, rhizotomy) has become more frequent. Family-directed use of holistic approaches for their children with cerebral palsy includes the widespread adoption of complementary and alternative therapies; however, the prevalence of their use and the cost of these options are unknown. Traditional medical techniques (physiotherapy, bracing, and orthopaedic musculoskeletal surgery) remain the mainstay of treatment strategies at this time. This seminar addresses only the musculoskeletal issues associated with cerebral palsy and only indirectly discusses the cognitive, medical, and social issues associated with this diagnosis.

Electrical stimulation in the management of spastic deformity

This article outlines a nonsurgical approach that includes neuromuscular electrical stimulation and dynamic bracing for the management of spastic deformity in cerebral palsy. Neuromuscular electrical stimulation is used commonly for lower extremity spasticity. Its clinical application in upper extremity spasticity, together with dynamic bracing, is a new entity providing predictable and quick short-term results with significant improvement in quality of life.

Gait and hand function enhancement following training with a multi-segment hybrid-orthosis stimulation system in stroke patients

The majority of stroke survivors continue to suffer residual functional deficits due to weakness and inadequate motor control of their paretic muscles. Non-invasive functional electrical stimulation has been limited to stimulation of only 1-2 muscle groups. The purpose of this study was to test if the use of a multi-segment hybrid orthosis-stimulation system combined with electrically augmented functional training would promote improvement in gait and hand functions of patients with chronic hemiparesis. A control group (n = 9) received individual instructions for specific functional training and self-exercised up to 60 minutes twice daily. The stimulated group (n = 10) received self-administered electrical stimulation training using the NESS system. Training time increased to 60 minutes twice daily and comprised of specific functional exercise. Each group trained for 3 months. Upper limb outcome measures included the Box & Block (B & B) and 3 sub-tests of the Jebsen-Taylor (J & T) battery. Gait outcomes included 10-meter walk time, speed, cadence, and number of steps. Post-test-pretest data were analyzed by unpaired t-tests (P = 0.05). The stimulated group improved significantly compared to the control group in B & B (7.9 +/- 4.5 vs 0.2 +/- 2.2 more blocks); J & T simulated feeding (12.6 +/- 14.8 vs 1.2 +/- 2.09 sec); J & T light object lift (8.2 +/- 9.7 vs. -0.3 +/- 2.8 sec); J & T heavy object lift (7.6 +/- 11.0 vs -0.8 +/- 1.6 sec); walk time (3.3 +/- 1.1 sec vs -0.3 +/- 1.8 sec); walking speed (0.33 +/- 0.12 vs. -0.01 +/- 0.1 m/sec); cadence (0.30 +/- 0.18 vs. -0.02 +/- 0.14 steps/sec). The number of steps over 10 m decreased 2.7 +/- 1.4 vs -0.2 +/- 1.98 steps. We concluded that electrically-dependent functional training with multi-segment hybrid orthosis-stimulation system can improve the studied functional outcomes of chronic stroke survivors.

The effects of long-term FES-assisted walking on intrinsic and reflex dynamic stiffness in spastic spinal-cord-injured subjects

The effects of long-term functional electrical stimulation (FES)-assisted walking on ankle dynamic stiffness were examined in spinal cord-injured (SCI) subjects with incomplete motor function loss. A parallel-cascade system identification method was used to identify intrinsic and reflex contributions to dynamic ankle stiffness at different ankle positions while subjects remained relaxed. Intrinsic stiffness dynamics were well modeled by a linear second-order model relating intrinsic torque to joint position. Reflex stiffness dynamics were accurately described by a linear third-order model relating halfwave rectified velocity to reflex torque. We examined four SCI subjects before and after long-term FES-assisted walking (> 16 mo). Another SCI subject, who used FES for only five months was examined 12 mo latter to serve as a non-FES, SCI control. Reflex stiffness decreased in FES subjects by an average of 53% following FES-assisted walking, intrinsic stiffness also dropped by 45%. In contrast, both reflex and intrinsic stiffness increased in the non-FES, SCI control. These findings suggest that FES-assisted walking may have therapeutic effects, helping to reduce abnormal joint stiffness.

Management of upper limb dysfunction in children with cerebral palsy: a systematic review

Effective use of the upper limb can impact on educational outcomes, participation in activities of daily living and vocational options for many children with cerebral palsy (CP). This article presents the results of a systematic review of the literature on the management of upper limb dysfunction in children with CP. The range of management options includes therapies such as physiotherapy, occupational therapy, neurodevelopmental therapy and conductive education; peripheral splinting and casting; focal or generalized pharmacotherapy; and surgery to improve upper limb function or correct deformity. A literature search identified 60 papers, of which four were randomized controlled trials and 44 were prospective studies with objective outcome measures. Principal studies undertaken for each type of treatment and the efficacy of the different types of treatment were critically evaluated. In addition, the current level of evidence for each study was evaluated according to Sackett's (1989) model and ICIDH-2 classification. A close examination of two relatively new treatments for upper limb spasticity, constraint induced movement therapy and botulinum toxin type A (BTX-A) was conducted with reference to more extensive data on the efficacy of BTX-A in the lower limb.