Cervical dorsal rhizotomy for upper limbs spasticity. Case report.

Spasticity is a prevalent symptom of upper motor neuron syndrome, becoming debilitating when hindering voluntary movement and motor function and causing contractures and pain. Functional neurosurgery plays a crucial role in treating severe spasticity. Despite extensive literature on SDR for lower limb spasticity, there is a scarcity of papers regarding the procedure in the cervical region to alleviate upper limb spasticity. This case report details a cervical dorsal rhizotomy (CDR) performed for upper limb spasticity, resulting in significant improvement in spasticity with sustained outcomes and low complication rates. Neuroablative procedures like CDR become an option to treat spasticity.

Classification of Motor Imagery Tasks Derived from Unilateral Upper Limb based on a Weight-optimized Learning Model.

BACKGROUND: The accuracy of decoding fine motor imagery (MI) tasks remains relatively low due to the dense distribution of active areas in the cerebral cortex. METHODS: To enhance the decoding of unilateral fine MI activity in the brain, a weight-optimized EEGNet model is introduced that recognizes six types of MI for the right upper limb, namely elbow flexion/extension, wrist pronation/supination and hand opening/grasping. The model is trained with augmented electroencephalography (EEG) data to learn deep features for MI classification. To address the sensitivity issue of the initial model weights to classification performance, a genetic algorithm (GA) is employed to determine the convolution kernel parameters for each layer of the EEGNet network, followed by optimization of the network weights through backpropagation. RESULTS: The algorithm's performance on the three joint classification is validated through experiment, achieving an average accuracy of 87.97%. The binary classification recognition rates for elbow joint, wrist joint, and hand joint are respectively 93.92%, 90.2%, and 94.64%. Thus, the product of the two-step accuracy value is obtained as the overall capability to distinguish the six types of MI, reaching an average accuracy of 81.74%. Compared to commonly used neural networks and traditional algorithms, the proposed method outperforms and significantly reduces the average error of different subjects. CONCLUSIONS: Overall, this algorithm effectively addresses the sensitivity of network parameters to initial weights, enhances algorithm robustness and improves the overall performance of MI task classification. Moreover, the method is applicable to other EEG classification tasks; for example, emotion and object recognition.

Detecting Asymmetry of Upper Limb Activity with Accelerometry in Infants at Risk for Unilateral Spastic Cerebral Palsy.

AIMS: To examine whether accelerometry can quantitate asymmetry of upper limb activity in infants aged 3-12 months at risk for developing unilateral spastic cerebral palsy (USCP). METHOD: A prospective study was performed in 50 infants with unilateral perinatal brain injury at high risk of developing USCP. Triaxial accelerometers were worn on the ipsilateral and contralesional upper limb during the Hand Assessment for Infants (HAI). Infants were grouped in three age intervals (3-5 months, 5-7.5 months and 7.5 until 12 months). Each age interval group was divided in a group with and without asymmetrical hand function based on HAI cutoff values suggestive of USCP. RESULTS: In a total of 82 assessments, the asymmetry index for mean upper limb activity was higher in infants with asymmetrical hand function compared to infants with symmetrical hand function in all three age groups (ranging from 41 to 51% versus - 2-6%, p < 0.01), while the total activity of both upper limbs did not differ. CONCLUSIONS: Upper limb accelerometry can identify asymmetrical hand function in the upper limbs in infants with unilateral perinatal brain injury from 3 months onwards and is complementary to the Hand Assessment for Infants.

Evolution of muscle coordination and mechanical output following four weeks of arm cranking submaximal training.

Muscle synergies is extensively studied to understand how the neuromusculoskeletal system deals with abundancy. The synergies represent covariant muscles that acts as building blocks for movement production. Nevertheless, little is known on how those synergies evolve following training, learning and expertise. This study reports the influence a 4-weeks submaximal training of arm-cranking on novice participants' muscle synergies. METHODS: 12 participants performed 8 sessions of submaximal training for 4 weeks. One session consisted in two 30-second-maximal power tests followed by six 2-minutes-bouts at 30% of maximal recorded power. Cranking torque and EMG of 11 muscles were recorded during the entire protocol. After EMG normalization, muscle synergies were extracted using NNMF. Similarity was computed using cross-correlation and cosine similarities and statistical evolution across training was tested using repeated measured ANOVA. RESULTS: While maximal power increased across training days nor torque management, EMG or muscle synergies were significantly affected by submaximal training. Nevertheless, results suggest slights modifications of muscle synergies across day despite to non-significant differences. DISCUSSION: Despite the strong complexity of the upper limbs anatomy, our results showed that training didn't induce significant changes in movement realization (mechanical and coordination level). A low-dimensional organization of muscle synergies is selected from the first day and kept through the following training days, despite slight but non-significant modifications.This study supports the hypothesis that motor control for movement production could be simplify using low-dimensional building blocks (muscle synergies). Such building blocks allow stability in movement execution and are slightly adjusted to fit movement requirements with training.

Upper limb cranking asymmetry during a Wingate anaerobic test in wheelchair basketball players.

INTRODUCTION: Interlimb asymmetry of strength and/or motor coordination could limit the performance of wheelchair athletes or increase their risk of injury. Studies of interlimb asymmetry in the lower limbs have shown high between-subject variability that does not depend on the side of dominance and that does not change with fatigue. Upper limb asymmetry is particularly large in manual wheelchair athletes with a lower degree of impairment. The aim of this study was to evaluate interlimb asymmetry of forces developed during an upper limb Wingate anaerobic test, the effects of fatigue on force, and differences between high- and low-point players. METHOD: Twenty-five wheelchair basketball players (13 females and 12 males) of male and female national French teams performed a 30s anaerobic Wingate test on an arm ergometer. Participants were classified into two functional categories, high-point (classed from 3 to 4.5) and low-point (classed from 1 to 2.5), according to the International Wheelchair Basketball Federation classification. Left and right arm forces were measured during the pushing and pulling phases at peak power, 10s, and the end of the 30s test. RESULTS: Upper limb asymmetry changed with fatigue during each phase. Force asymmetry differed between peak power, 10s and 30s, with no consistent increase or decrease. Asymmetry did not differ significantly between low- and high-point players but tended to be greater in high-point players. Asymmetry tended to be greater in the females, with significant differences between the males and females in the push phase. CONCLUSION: Inter-subject variability was high, but forces were asymmetric for most participants, especially females. The Wingate anaerobic test could highlight problematic asymmetries that might impact daily life or sports performance.

Assessment of an IMU-Based Experimental Set-Up for Upper Limb Motion in Obese Subjects.

In recent years, wearable systems based on inertial sensors opened new perspectives for functional motor assessment with respect to the gold standard motion capture systems. The aim of this study was to validate an experimental set-up based on 17 body-worn inertial sensors (Awinda, Xsens, The Netherlands), addressing specific body segments with respect to the state-of-the art system (VICON, Oxford Metrics Ltd., Oxford, UK) to assess upper limb kinematics in obese, with respect to healthy subjects. Twenty-three obese and thirty healthy weight individuals were simultaneously acquainted with the two systems across a set of three tasks for upper limbs (i.e., frontal arm rise, lateral arm rise, and reaching). Root Mean Square error (RMSE) was computed to quantify the differences between the measurements provided by the systems in terms of range of motion (ROM), whilst their agreement was assessed via Pearson's correlation coefficient (PCC) and Bland-Altman (BA) plots. In addition, the signal waveforms were compared via one-dimensional statistical parametrical mapping (SPM) based on a paired t-test and a two-way ANOVA was applied on ROMs. The overall results partially confirmed the correlation and the agreement between the two systems, reporting only a moderate correlation for shoulder principal rotation angle in each task (r~0.40) and for elbow/flexion extension in obese subjects (r = 0.66), whilst no correlation was found for most non-principal rotation angles (r < 0.40). Across the performed tasks, an average RMSE of 34° and 26° was reported in obese and healthy controls, respectively. At the current state, the presence of bias limits the applicability of the inertial-based system in clinics; further research is intended in this context.

Manual Muscle Testing of the Scapula and the Upper Limb through Bedside Examination.

Neurological examination is an important tool in diagnosing patients with neurological and neurosurgical conditions. As the complexity and knowledge of neurological and neurosurgical conditions increases, we are now required to learn and indoctrinate our peers and students with the correct skills and methods of examination. Emphasis on the correct techniques of testing muscle strength is essential to avoid errors in recording muscle power and in testing specific muscles which may have overlapping functions. The manual muscle testing of muscles of scapula and upper limbs was performed as to mimic a bedside clinical examination and involved an examiner, a patient and a videographer. The manual muscle testing has been performed in rostrocaudal manner starting from the scapula and ending with the thumbs. A reliable and consistent method of manual muscle testing is lacking among students and clinicians. By adhering to the methods delineated in our text and accompanying video, we hope to reduce inter-examiner variability and increase the reliability and validity of this important examination.

Relationship between scapular elevation exercises with different alignments and activity of the trapezius and levator scapulae muscles.

[Purpose] This study aimed to examine whether scapular elevation exercises in sitting positions with different alignments lead to contractions of the trapezius and levator scapulae muscles. [Participants and Methods] The participants were 25 males, measured in four sitting positions with different alignments. Spine alignment was assessed by measuring the head protrusion, upper thoracic spine tilt, and pelvic tilt angles. Upper limb alignment was evaluated using the scapula tilt angle, scapula rotation angle, and distance between scapular spinous processes. Scapular elevation exercises were measured, and the thickness of the trapezius and levator scapulae muscles were measured in resting and elevated positions, with changes in muscle thickness. [Results] The trapezius muscle thickness was greater in the sitting position with less thoracic spine tilt and scapula tilt angles. Conversely, the levator scapulae muscle thickness was greater in the sitting position with more thoracic spine tilt and scapula tilt angles. [Conclusion] Scapular elevation exercises induce separate contractions of the trapezius and levator scapulae muscles by modifying the alignment of the spine and upper limbs.

Digital pressure with laser Doppler flowmetry is better than photoplethysmography to characterize peripheral arterial disease of the upper limbs in end-stage renal disease patients.

OBJECTIVE: There is no consensual definition of significant peripheral arterial disease of the upper limbs. Patients with end-stage renal disease are usually explored with Doppler ultrasound, which seems insufficient to characterize and quantify the arterial disease in this anatomic site. Candidates for haemodialysis access tend to be increasingly older and have polyvascular disease, and a better assessment of the vascular status of their upper limbs with finger systolic blood pressure is necessary. Photoplethysmography is simple and currently used in practice, but laser Doppler flowmetry may be more sensitive for low values. Our objective is to investigate additional information in the digit assessment over the ultrasound assessment of the upper limbs of patients awaiting haemodialysis and compare digital pressure values taken by photoplethysmography and laser Doppler. METHODS: All included patients with end-stage renal disease scheduled for haemodialysis access received a prospective evaluation of their upper limbs with a clinical examination of the hands, an arterial upper limb Doppler ultrasound, and finger systolic blood pressure using photoplethysmography and laser Doppler flowmetry. Significant upper limb arterial disease was defined by a finger systolic blood pressure below 60 mm Hg or a finger brachial pressure index below 0.7. RESULTS: Twenty-four patients were included in the study. In all, 41.7% of patients (n = 10) had parietal calcifications to the antebrachial arteries on Doppler ultrasound, 8.3% of patients (n = 2) had bilateral finger systolic blood pressure values below 60 mm Hg with laser Doppler flowmetry (but not confirmed with photoplethysmography), and 16.6% of patients (n = 4) had a finger brachial pressure index below 0.7 on both laser Doppler flowmetry and photoplethysmography. While there was an agreement between these two methods, higher values were recorded with photoplethysmography. The Pearson coefficient was 0.493 for the median of basal digital pressures in absolute values and 0.489 for finger brachial pressure index (p < 0.001). CONCLUSION: Our study confirms the need to evaluate significant upper limb arterial disease in patients with end-stage renal disease not only with Doppler ultrasound but also with an evaluation of the finger systolic blood pressure. The correlation of the finger systolic blood pressure values using laser Doppler flowmetry and photoplethysmography was poor, which was probably due to an overestimation of the pressures with photoplethysmography. Despite the absence of a gold standard, we suggest that Laser Doppler flowmetry should be used rather than photoplethysmography to better characterize significant peripheral arterial disease of the upper limbs in patients with end-stage renal disease, particularly before creation of a new haemodialysis access. Protocol Record on clinical trial 38RC19.285.

Acute effects of two caffeine doses on bar velocity during the bench press exercise among women habituated to caffeine: a randomized, crossover, double-blind study involving control and placebo conditions.

PURPOSE: The main goal of this study was to evaluate the effectiveness of two different doses of caffeine (3 and 6 mg/kg) to enhance bar velocity during the bench press in women habituated to caffeine. METHODS: Twelve recreationally trained women (age: 23.3 ± 0.8 years, body mass: 60.7 ± 5.7 kg, bench press one-repetition maximum (1RM): 44.3 ± 7.8 kg, daily caffeine ingestion: 5.7 ± 2.0 mg/kg/day) participated in a randomized double-blind experimental design. Each participant performed four different experimental sessions: after no supplementation (control, CON), after ingesting 3 and 6 mg/kg of caffeine (CAF-3 and CAF-6, respectively), or after ingesting a placebo (PLAC). In each experimental session, the participants performed 3 sets of 3 repetitions of the bench press exercise at 50% 1RM. RESULTS: A two-way repeated-measures ANOVA with subsequent post hoc analyses indicated significant increases in peak velocity (p < 0.01; ES = 0.91) and mean velocity (p < 0.01; ES = 0.78) after the intake of CAF-6 compared to CON. The study did not show significant differences in bar velocity between CAF-6 and PLAC and between CAF-3 and PLAC. No significant differences in bar velocity were observed between CAF-3 and CAF-6 conditions. CONCLUSION: These results suggest that 6 mg/kg of caffeine can be an effective dose to improve power-specific training outcomes in women habituated to caffeine. However, the ergogenic effect of 6 mg/kg of caffeine may be derived from a combination of biological effects and expectancy, as this dose was only superior to the control condition with no differences over the placebo.

Effectiveness of kinesiology taping on the functions of upper limbs in patients with stroke: a meta-analysis of randomized trial.

BACKGROUND: Kinesiology tape (KT), a water-resistant and elastic tape which is well known measure for preventing musculoskeletal injuries, has recently gained popularity in neurological rehabilitation. This is a systematic and meta-analysis study, useful both to evaluate the efficacy of kinesiology taping on the functions of upper limbs in patients with stroke and to collect the main outcomes evaluated in the analyzed studies. METHODS: A comprehensive literature search of electronic databases including Medline, Web of science, Embase, Cochrane Central Register of Controlled Trials, Physiotherapy Evidence Database (PEDro), WANFANG, and the China National Knowledge Infrastructure (CNKI). Additional articles were obtained by scanning reference lists of included studies and previous reviews. Keywords were "kinesiology taping," "kinesio," "kinesio taping," "tape" and "stroke," "hemiplegia," "hemiplegic paralysis," "apoplexy," "hemiparesis," "upper extremity," "upper limb." All the RCTs were included. Quality assessment was performed using Cochrane criteria. Upper extremity function and pain intensity was pooled as the primary outcome, and shoulder subluxation, muscle spasticity, general disability, PROM of abduction, and adverse effects as secondary outcomes. RESULTS: Twelve articles were included. Pooled data provided evidence that there was significance between kinesiology taping groups and control groups in pain intensity (standardized mean difference - 0.79, 95% CI - 1.39 to - 0.19), shoulder subluxation (standardized mean difference - 0.50, 95%CI - 0.80 to - 0.20), general disability (standardized mean difference 0.35, 95%CI 0.10 to 0.59), upper extremity function (standardized mean difference 0.61, 95%CI 0.18 to 1.04), and the PROM of flexion (standardized mean difference 0.63, 95%CI 0.28 to 0.98). CONCLUSION: Current evidence suggested that kinesiology taping could be recommended to improve upper limb function in patients with stroke in pain intensity, shoulder subluxation, general disability, upper extremity function, and the PROM of flexion. ETHICS AND DISSEMINATION: Ethical approval requirements are not necessary for this review. This systematic review and meta-analysis will be disseminated online and on paper to help guide the clinical practice better. PROSPERO REGISTRATION NUMBER: CRD42020179762.

Assessment of the Mechanical Support Characteristics of a Light and Wearable Robotic Exoskeleton Prototype Applied to Upper Limb Rehabilitation.

Robotic exoskeletons are active devices that assist or counteract the movements of the body limbs in a variety of tasks, including in industrial environments or rehabilitation processes. With the introduction of textile and soft materials in these devices, the effective motion transmission, mechanical support of the limbs, and resistance to physical disturbances are some of the most desirable structural features. This paper proposes an evaluation protocol and assesses the mechanical support properties of a servo-controlled robotic exoskeleton prototype for rehabilitation in upper limbs. Since this prototype was built from soft materials, it is necessary to evaluate the mechanical behavior in the areas that support the arm. Some of the rehabilitation-supporting movements such as elbow flexion and extension, as well as increased muscle tone (spasticity), are emulated. Measurements are taken using the reference supplied to the system's control stage and then compared with an external high-precision optical tracking system. As a result, it is evidenced that the use of soft materials provides satisfactory outcomes in the motion transfer and support to the limb. In addition, this study lays the groundwork for a future assessment of the prototype in a controlled laboratory environment using human test subjects.

Muscle-MRI and Functional Levels for the Evaluation of Upper Limbs in Duchenne Muscular Dystrophy: A Critical Review of the Literature.

Many qualitative and quantitative Magnetic Resonance Imaging (MRI) techniques have been applied to evaluate muscle fat degeneration in Duchenne muscular dystrophy (DMD) subjects, but only few studies have focused on the upper limbs. We reviewed the literature in order to evaluate the association between muscle MRI findings and motor function levels in the upper limbs of DMD patients. Ten studies with upper limb muscle MRI data were available. Four explored all upper limb segments, while six explored only the forearm. Functional assessments were performed in nine of the ten studies. All of the studies showed a significant correlation between muscle MRI changes and motor function levels in both ambulant and non-ambulant DMD patients.

Advancements in sex estimation using the diaphyseal cross-sectional geometric properties of the lower and upper limbs.

This paper introduces an automated method for estimating sex from the lower and upper limbs based on diaphyseal CSG properties. The proposed method was developed and evaluated using 389 femurs, 412 tibias, and 404 humeri of adult individuals from a modern Greek reference sample, the Athens Collection. The skeletal properties, which were extracted with the CSG-Toolkit, were analyzed with step-wise DFA (evaluated with LOOCV) and subsequently with RBF kernel SVM supervised learning. SVM cross-validation was based on a 20-fold stratified random sample splitting as well as a chronological split based on year of birth to further assess the effect of secular change in sex estimation capacity. Maximum cross-validated classification accuracy from step-wise DFA reached 94.8% for the femur, 94.7% for the tibia, and 97.3% for the humerus, whereas SVM cross-validated results were similar although slightly lower, mainly due to the more strict cross-validation scheme. Our results suggest that the proposed sex estimation method is reasonably robust to secular change, since there was limited loss in classification accuracy between different chronological groups, despite the presence of secular change in stature of the Greek population during the examined period. The proposed method has been implemented as a function for the GNU Octave environment, named estimate_sex, which comprises a self-intuitive graphical user interface for facilitating sex estimation and is freely available under a suitable license.

Test-retest reliability of static and dynamic motor fatigability protocols using grip and pinch strength in typically developing children.

Upper limb motor fatigability is an important debilitating factor for activities of daily living in clinical pediatric populations. However, the reliability of fatigability protocols in these populations is currently unknown. Therefore, the current study investigates test-retest reliability of a static and dynamic motor fatigability protocol for grip and pinch strength in typically developing children (TDC). Eighty-nine TDC (35 boys, 54 girls; mean age 10 years 11 months) used a grip and pinch dynamometer for static (sustained) and dynamic (repeated) contractions during 30s. For static motor fatigability (SFI), mean (Fmean) and SD (Fvar) of force were calculated, and for dynamic motor fatigability, F mean and number of peaks (Npeaks) were calculated. Intraclass correlation coefficients (ICC) were calculated. ICCs of F mean in static and dynamic motor fatigability were high (ICC: 0.94-0.96 and 0.91-0.98). ICCs were moderate to high for F var (ICC: 0.67-0.85). The SFI showed moderate ICCs (ICC: 0.69-0.77). ICCs were moderate to high for N peaks (ICC: 0.78-0.91).Conclusion: The results suggest that static and dynamic motor fatigability in for grip and pinch can be used reliably in TD children aged 6-18 years. What is Known: •Psychometric properties of motor fatigability protocols using grip and pinch in children are lacking. •Motor fatigability in grip and pinch is an important debilitating symptom in multiple neurologic populations. What is New: •Static fatigability can be investigated using a 30-s maximum sustained grip strength protocol in children. •Dynamic fatigability can be investigated using a 30-s maximum repeated grip strength protocol in children.

Hand Function as Predictor of Motor Symptom Severity in Individuals with Parkinson's Disease.

INTRODUCTION: Parkinson's disease (PD) leads to deficits in upper limb strength and manual dexterity and consequently resulting in functional impairment. Handgrip strength is correlated with the motor symptom severity of the disease, but there is a gap in the literature about the influence of freezing in PD patients. OBJECTIVE: The objective is to study the correlation between handgrip strength and motor symptom severity considering the freezing phenomenon and to verify variables that can predict Unified Parkinson's Disease Rating Scale (UPDRS) III. METHODS: This is a multicenter cross-sectional study in PD. 101 patients were divided into 2 groups: freezing of gait (FOG) (n = 51) and nonfreezing (nFOG) (n = 52). Freezing of Gait Questionnaire (FOGQ); UPDRS II and III sections; Hoehn and Yahr (HY) scale; handgrip dynamometry (HD); 9 Hole Peg Test (9-HPT) were assessed. RESULTS: In both groups, HD was correlated to UPDRS III (nFOG: -0.308; FOG: -0.301), UPDRS total (nFOG: -0.379; FOG: -0.368), UPDRS item 23 (nFOG: -0.404; FOG: -0.605), and UPDRS item 24 (nFOG: -0.405; FOG: -0.515). For the correlation to UPDRS II (0.320) and 9-HPT (-0.323), only nFOG group presented significance. For the UPDRS 25 (-0.437), only FOG group presented statistical significance. The UPDRS III can be predicted by 9-HPT, age, and HY in nFOG patients (Adjusted R2 = 0.416). In FOG group, UPDRS III can be predicted by HD, 9-HPT, age, and HY (Adjusted R2 = 0.491). CONCLUSION: Handgrip strength showed to be predictive of motor impairment only in the FOG group. Our results showed clinical profile differences of motor symptoms considering freezers and nonfreezers with PD.

Investigation of psychosocial factors on upper limb musculoskeletal disorders and the prevalence of its musculoskeletal disorders among nurses: a systematic review and meta-analysis.

OBJECTIVE: Musculoskeletal disorders are one of the most important occupational problems especially among nurses. The aim of this study was to investigate the prevalence of musculoskeletal disorders in upper limbs and its associated psychosocial factors in the workplace. METHODS: A systematic review was conducted by searching the Medline/PubMed, EMBASE, Scopus, ISI/web of knowledge and Google Scholar databases. The authors classified studies into categories of psychological work stressors and musculoskeletal problems. The statistical analysis was performed using Stata software. RESULTS: We found 1742 articles in our initial search. After reviewing the titles, abstracts and full texts, 66 articles were finally analyzed. Psychosocial factors affecting the prevalence of upper limb musculoskeletal disorders among nurses were identified which included boring work, inadequate staffing, job demands, insufficient support, time pressure, decision latitude, job dissatisfaction, and job stress. There was a significant relationship between these factors and prevalence of musculoskeletal disorders in the wrists, shoulders, neck and shoulders, and wrists and hands. CONCLUSION: Collectively, the results of this study provide strong evidence of some psychosocial factors affecting the prevalence of upper limb musculoskeletal disorders among nurses. Thus, organizational interventions to minimize these stressors may be promising in reducing one risk factor for the development of nurses' musculoskeletal disorders. These interventions should not only consider the factors of physical ergonomics but also seek to improve the organizational aspects of the workplace.

Long term treatment with ataluren-the Swedish experience.

INTRODUCTION: Ataluren is a relatively new treatment for male patients with Duchenne muscular dystrophy (DMD) due to a premature stop codon. Long-term longitudinal data as well as efficacy data on non-ambulant patients are still lacking. Here we present the results from a long-term follow-up study of all DMD patients treated with ataluren and followed at the Queen Silvia Children's Hospital in Gothenburg, Sweden, with focus on the evolution of patients' upper motor and respiratory function over time. METHODS: This is a retrospective longitudinal case-series study of all male DMD patients treated with ataluren and followed at the Queen Silvia Children's Hospital in Gothenburg, Sweden, since 2008. RESULTS: Our eleven patients had a median exposure to ataluren of 2312 days which is almost a fourfold higher than previous studies. Loss of ambulation occurred at a median age of 13.2 years. Patients who lost ambulation prior to 13.2 years of age had received ataluren for 5 years, whereas patients who continued to be ambulatory after 13.2 years of age had received ataluren for 6.5 years until loss of ambulation or last follow-up if still ambulatory. Four of six non ambulatory patients had Performance of the Upper Limb scores above the expected mean values over time. All but one patient maintained a pulmonary decline above the expected over time. All ambulatory patients increased in their predicted forced vital capacity (FVC) with 2.8 to 8.2% annually. Following loss of ambulation, 5 of 6 patients declined in predicted FVC (%), with annual rate of decline varying from 1.8 to 21.1%. The treatment was safe and well tolerated throughout the follow-up period. CONCLUSIONS: This is the first study to present long-term cumulative treatment outcomes over a median period of 6.3 years on ataluren treatment. Our results indicate a delay in loss of ambulation, as well as a slower decline in FVC and upper limb motor function even after loss of ambulation. We suggest that treatment with ataluren should be initiated as soon as the diagnosis is confirmed, closely monitored and, in case of sustainable benefit, continued even after loss of ambulation.

Integration and Testing of a High-Torque Servo-Driven Joint and Its Electronic Controller with Application in a Prototype Upper Limb Exoskeleton.

Mechatronic systems that allow motorized activation in robotic exoskeletons have evolved according to their specific applications and the characteristics of the actuation system, including parameters such as size, mechanical properties, efficiency, and power draw. Additionally, different control strategies and methods could be implemented in various electronic devices to improve the performance and usability of these devices, which is desirable in any application. This paper proposes the integration and testing of a high-torque, servo-driven joint and its electronic controller, exposing its use in a robotic exoskeleton prototype as a case study. Following a brief background review, the development and implementation of the proposal are presented, allowing the control of the servo-driven joint in terms of torque, rotational velocity, and position through a straightforward, closed-loop control architecture. Additionally, the stability and performance of the servo-driven joint were assessed with and without load. In conclusion and based on the obtained results, the servo-driven joint and its control system demonstrate consistent performance under the proposed test protocol (max values: angular velocity 97 °/s, torque 33 Nm, positioning RMSE 1.46°), enabling this approach for use in various applications related to robotic exoskeletons, including human performance enhancement, rehabilitation, or support for daily living activities.

Artificial Intelligence-Based Wearable Robotic Exoskeletons for Upper Limb Rehabilitation: A Review.

Processing and control systems based on artificial intelligence (AI) have progressively improved mobile robotic exoskeletons used in upper-limb motor rehabilitation. This systematic review presents the advances and trends of those technologies. A literature search was performed in Scopus, IEEE Xplore, Web of Science, and PubMed using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology with three main inclusion criteria: (a) motor or neuromotor rehabilitation for upper limbs, (b) mobile robotic exoskeletons, and (c) AI. The period under investigation spanned from 2016 to 2020, resulting in 30 articles that met the criteria. The literature showed the use of artificial neural networks (40%), adaptive algorithms (20%), and other mixed AI techniques (40%). Additionally, it was found that in only 16% of the articles, developments focused on neuromotor rehabilitation. The main trend in the research is the development of wearable robotic exoskeletons (53%) and the fusion of data collected from multiple sensors that enrich the training of intelligent algorithms. There is a latent need to develop more reliable systems through clinical validation and improvement of technical characteristics, such as weight/dimensions of devices, in order to have positive impacts on the rehabilitation process and improve the interactions among patients, teams of health professionals, and technology.