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Neurological disorders such as stroke, Parkinson's disease (PD), and severe traumatic brain injury (sTBI) are leading global causes of disability and mortality. This study aimed to assess the ability to walk of patients with sTBI, stroke, and PD, identifying the differences in dynamic postural stability, symmetry, and smoothness during various dynamic motor tasks. Sixty people with neurological disorders and 20 healthy participants were recruited. Inertial measurement unit (IMU) sensors were employed to measure spatiotemporal parameters and gait quality indices during different motor tasks. The Mini-BESTest, Berg Balance Scale, and Dynamic Gait Index Scoring were also used to evaluate balance and gait. People with stroke exhibited the most compromised biomechanical patterns, with lower walking speed, increased stride duration, and decreased stride frequency. They also showed higher upper body instability and greater variability in gait stability indices, as well as less gait symmetry and smoothness. PD and sTBI patients displayed significantly different temporal parameters and differences in stability parameters only at the pelvis level and in the smoothness index during both linear and curved paths. This study provides a biomechanical characterization of dynamic stability, symmetry, and smoothness in people with stroke, sTBI, and PD using an IMU-based ecological assessment.
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Marcha , Enfermedad de Parkinson , Equilibrio Postural , Accidente Cerebrovascular , Humanos , Masculino , Marcha/fisiología , Femenino , Persona de Mediana Edad , Enfermedad de Parkinson/fisiopatología , Equilibrio Postural/fisiología , Fenómenos Biomecánicos/fisiología , Anciano , Accidente Cerebrovascular/fisiopatología , Caminata/fisiología , Adulto , Lesiones Traumáticas del Encéfalo/fisiopatología , Velocidad al Caminar/fisiologíaRESUMEN
OBJECTIVE: To investigate the usefulness of inertial measurement units (IMUs) in the assessment of motor function of the upper limb (UL) in accordance with the international classification of functioning (ICF). DATA SOURCES: PubMed; Scopus; Embase; WoS and PEDro databases were searched from inception to 1 February 2022. METHODS: The current systematic review follows PRISMA recommendations. Articles including IMU assessment of UL in stroke individuals have been included and divided into four ICF categories (b710, b735, b760, d445). We used correlation meta-analysis to pool the Fisher Z-score of each correlation between kinematics and clinical assessment. RESULTS: A total of 35 articles, involving 475 patients, met the inclusion criteria. In the included studies, IMUs have been employed to assess the mobility of joint functions (n = 6), muscle tone functions (n = 4), control of voluntary movement functions (n = 15), and hand and arm use (n = 15). A significant correlation was found in overall meta-analysis based on 10 studies, involving 213 subjects: (r = 0.69) (95% CI: 0.69/0.98; p < 0.001) as in the d445 (r = 0.71) and b760 (r = 0.64) ICF domains, with no heterogeneity across the studies. CONCLUSION: The literature supports the integration of IMUs and conventional clinical assessment in functional evaluation of the UL after a stroke. The use of a limited number of wearable sensors can provide additional kinematic features of UL in all investigated ICF domains, especially in the ADL tasks when a strong correlation with clinical evaluation was found.
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Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Extremidad Superior , Mano , Fenómenos BiomecánicosRESUMEN
BACKGROUND: Multiple Sclerosis (MS) is a chronic inflammatory, demyelinating, degenerative disease of the central nervous system and the second most frequent cause of permanent disability in young adults. One of the most common issues concerns the ability to perform postural and gait tasks while simultaneously completing a cognitive task (namely, dual-task DT). AIM: Assessing cognitive-motor dual-task training effectiveness in patients with Multiple Sclerosis (PwMS) for dynamic gait quality when walking on straight, curved, and blindfolded paths. DESIGN: Two-arm single-blind randomized controlled trial. Follow-up at 8 weeks. SETTING: Neurorehabilitation Hospital. POPULATION: A sample of 42 PwMS aged 28-71, with a score of 4.00±1.52 on the Expanded Disability Status Scale were recruited. METHODS: Participants were randomized in conventional (CTg) neurorehabilitation and dual-task training (DTg) groups and received 12 sessions, 3 days/week/4 weeks. They were assessed at baseline (T0), after the treatment (T1), and 8 weeks after the end of the treatment (T2) through Mini-BESTest, Tinetti Performance Oriented Mobility Assessment, Modified Barthel Index, and a set of spatiotemporal parameters and gait quality indices related to stability, symmetry, and smoothness of gait extracted from initial measurement units (IMUs) data during the execution of the 10-meter Walk Test (10mWT), the Figure-of-8 Walk Test (Fo8WT) and the Fukuda Stepping Test (FST). RESULTS: Thirty-one PwMS completed the trial at T2. Significant improvement within subjects was found in Mini-BESTest scores for DTg from T0 to T1. The IMU-based assessment indicated significant differences in stability (P<0.01) and smoothness (P<0.05) measures between CTg and DTg during 10mWT and Fo8WT. Substantial improvements (P<0.017) were also found in the inter-session comparison, primarily for DTg, particularly for stability, symmetry, and smoothness measures. CONCLUSIONS: This study supports the effectiveness of DT in promoting dynamic motor abilities in PwMS. CLINICAL REHABILITATION IMPACT: Cognitive-motor DT implemented into the neurorehabilitation conventional program could be a useful strategy for gait and balance rehabilitation.
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Esclerosis Múltiple , Adulto Joven , Humanos , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/rehabilitación , Método Simple Ciego , Terapia por Ejercicio , Marcha/fisiología , Cognición , Equilibrio Postural/fisiologíaRESUMEN
BACKGROUND: Since birth, during the exploration of the environment to interact with objects, we exploit both the motor and sensory components of the upper limb (UL). This ability to integrate sensory and motor information is often compromised following a stroke. However, to date, rehabilitation protocols are focused primarily on recovery of motor function through physical therapies. Therefore, we have planned a clinical trial to investigate the effect on functionality of UL after a sensorimotor transcranial stimulation (real vs sham) in add-on to robot-assisted therapy in the stroke population. METHODS: A randomised double-blind controlled trial design involving 32 patients with a single chronic stroke (onset > 180 days) was planned. Each patient will undergo 15 consecutive sessions (5 days for 3 weeks) of paired associative stimulation (PAS) coupled with UL robot-assisted therapy. PAS stimulation will be administered using a bifocal transcranial magnetic stimulator (TMS) on the posterior-parietal cortex and the primary motor area (real or sham) of the lesioned hemisphere. Clinical, kinematics and neurophysiological changes will be evaluated at the end of protocol and at 1-month follow-up and compared with baseline. The Fugl-Meyer assessment scale will be the primary outcome. Secondly, kinematic variables will be recorded during the box-and-block test and reaching tasks using video analysis and inertial sensors. Single pulse TMS and electroencephalography will be used to investigate the changes in local cortical reactivity and in the interconnected areas. DISCUSSION: The presented trial shall evaluate with a multimodal approach the effects of sensorimotor network stimulation applied before a robot-assisted therapy training on functional recovery of the upper extremity after stroke. The combination of neuromodulation and robot-assisted therapy can promote an increase of cortical plasticity of sensorimotor areas followed by a clinical benefit in the motor function of the upper limb. TRIAL REGISTRATION: ClinicalTrials.gov NCT05478434. Registered on 28 Jul 2022.
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Robótica , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Rehabilitación de Accidente Cerebrovascular/métodos , Resultado del Tratamiento , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Extremidad Superior , Recuperación de la Función , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
INTRODUCTION: Monitoring systems at home are critical in the event of a fall, and can range from standalone fall detection devices to activity recognition devices that aim to identify behaviors in which the user may be at risk of falling, or to detect falls in real-time and alert emergency personnel. AREAS COVERED: This review analyzes the current literature concerning the different devices available for home fall detection. EXPERT OPINION: Included studies highlight how fall detection at home is an important challenge both from a clinical-assistance point of view and from a technical-bioengineering point of view. There are wearable, non-wearable and hybrid systems that aim to detect falls that occur in the patient's home. In the near future, a greater probability of predicting falls is expected thanks to an improvement in technologies together with the prediction ability of machine learning algorithms. Fall prevention must involve the clinician with a person-centered approach, low cost and minimally invasive technologies able to evaluate the movement of patients and machine learning algorithms able to make an accurate prediction of the fall event.
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Accidentes por Caídas , Inteligencia Ambiental , Humanos , Accidentes por Caídas/prevención & control , Movimiento , Algoritmos , Aprendizaje AutomáticoRESUMEN
Auditory stimulation activates brain areas associated with higher cognitive processes, like the prefrontal cortex (PFC), and plays a role in postural control regulation. However, the effects of specific frequency stimuli on upright posture maintenance and PFC activation patterns remain unknown. Therefore, the study aims at filling this gap. Twenty healthy adults performed static double- and single-leg stance tasks of 60s each under four auditory conditions: 500, 1000, 1500, and 2000 Hz, binaurally delivered through headphones, and in quiet condition. Functional near-infrared spectroscopy was used to measure PFC activation through changes in oxygenated hemoglobin concentration, while an inertial sensor (sealed at the L5 vertebra level) quantified postural sway parameters. Perceived discomfort and pleasantness were rated through a 0-100 visual analogue scale (VAS). Results showed that in both motor tasks, different PFC activation patterns were displayed at the different auditory frequencies and the postural performance worsened with auditory stimuli, compared to quiet conditions. VAS results showed that higher frequencies were considered more discomfortable than lower ones. Present data prove that specific sound frequencies play a significant role in cognitive resources recruitment and in the regulation of postural control. Furthermore, it supports the importance of exploring the relationship among tones, cortical activity, and posture, also considering possible applications with neurological populations and people with hearing dysfunctions.
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[This corrects the article DOI: 10.1016/j.heliyon.2022.e11021.].
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OBJECTIVE: To assess the long-term effects of bilateral subthalamic nucleus deep brain stimulation (STN-DBS) on gait in a cohort of advanced Parkinson's Disease (PD) patients. METHODS: This observational study included consecutive PD patients treated with bilateral STN-DBS. Different stimulation and drug treatment conditions were assessed: on-stimulation/off-medication, off-stimulation/off-medication, and on-stimulation/on-medication. Each patient performed the instrumented Timed Up and Go test (iTUG). The instrumental evaluation of walking ability was carried out with a wearable inertial sensor containing a three-dimensional (3D) accelerometer, gyroscope, and magnetometer. This device could provide 3D linear acceleration, angular velocity, and magnetic field vector. Disease motor severity was evaluated with the total score and subscores of the Unified Parkinson Disease Rating Scale part III. RESULTS: Twenty-five PD patients with a 5-years median follow-up after surgery (range 3-7) were included (18 men; mean disease duration at surgery 10.44 ± 4.62 years; mean age at surgery 58.40 ± 5.73 years). Both stimulation and medication reduced the total duration of the iTUG and most of its different phases, suggesting a long-term beneficial effect on gait after surgery. However, comparing the two treatments, dopaminergic therapy had a more marked effect in all test phases. STN-DBS alone reduced total iTUG duration, sit-to-stand, and second turn phases duration, while it had a lower effect on stand-to-sit, first turn, forward walking, and walking backward phases duration. CONCLUSIONS: This study highlighted that in the long-term after surgery, STN-DBS may contribute to gait and postural control improvement when used together with dopamine replacement therapy, which still shows a substantial beneficial effect.
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Estimulación Encefálica Profunda , Enfermedad de Parkinson , Núcleo Subtalámico , Masculino , Humanos , Persona de Mediana Edad , Enfermedad de Parkinson/terapia , Enfermedad de Parkinson/tratamiento farmacológico , Núcleo Subtalámico/fisiología , Estimulación Encefálica Profunda/métodos , Equilibrio Postural , Resultado del Tratamiento , Estudios de Tiempo y Movimiento , MarchaRESUMEN
The length of the standing long jump (SLJ) is widely recognized as an indicator of developmental motor competence or sports conditional performance. This work aims at defining a methodology to allow athletes/coaches to easily measure it using the inertial measurement units embedded on a smartphone. A sample group of 114 trained young participants was recruited and asked to perform the instrumented SLJ task. A set of features was identified based on biomechanical knowledge, then Lasso regression allowed the identification of a subset of predictors of the SLJ length that was used as input of different optimized machine learning architectures. Results obtained from the use of the proposed configuration allow an estimate of the SLJ length with a Gaussian Process Regression model with a RMSE of 0.122 m in the test phase, Kendall's τ < 0.1. The proposed models give homoscedastic results, meaning that the error of the models does not depend on the estimated quantity. This study proved the feasibility of using low-cost smartphone sensors to provide an automatic and objective estimate of SLJ performance in ecological settings.
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The ability to adapt anticipatory postural adjustments (APAs) in response to perturbations during single-joint movements is altered in people with chronic low back pain (LBP), but a comprehensive analysis during functional motor tasks is still missing. This study aimed to compare APAs and stepping characteristics during gait initiation between people with LBP and healthy controls, both in normal (without cue occurrence) condition and when an unexpected visual cue required to switch the stepping limb. Fourteen individuals with LPB and 10 healthy controls performed gait initiation in normal and switch conditions. The postural responses were evaluated through the analysis of center of pressure, propulsive ground reaction forces, trunk and whole-body kinematics, and activation onsets of leg and back muscles. During normal gait initiation, participants with LBP exhibited similar APAs and stepping characteristics to healthy controls. In the switch condition, individuals with LBP were characterized by greater mediolateral postural stability but decreased forward body motion and propulsion before stepping. The thorax motion was associated with forward propulsion parameters in both task conditions in people with LBP but not healthy controls. No between-group differences were found in muscle activation onsets. The results suggest that postural stability is prioritized over forward locomotion in individuals with LBP. Furthermore, the condition-invariant coupling between thorax and whole-body forward propulsion in LBP suggests an adaptation in the functional use of the thorax within the postural strategy, even in poor balance conditions.
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Dolor de la Región Lumbar , Humanos , Señales (Psicología) , Equilibrio Postural/fisiología , Marcha/fisiología , Locomoción/fisiología , Músculo Esquelético/fisiología , Postura/fisiología , Fenómenos BiomecánicosRESUMEN
OBJECTIVE: To evaluate correlations between speech and gait parameters in the long term and under different medication and subthalamic nucleus deep brain stimulation (STN-DBS) conditions in a cohort of advanced Parkinson's disease (PD) patients. METHODS: This observational study included consecutive PD patients treated with bilateral STN-DBS. Axial symptoms were evaluated using a standardized clinical-instrumental approach. Speech and gait were assessed by perceptual and acoustic analyses and by the instrumented Timed Up and Go (iTUG) test, respectively. Disease motor severity was evaluated with the total score and subscores of the Unified Parkinson's Disease Rating Scale (UPDRS) Part III. Different stimulation and drug treatment conditions were assessed: on-stimulation/off-medication, off-stimulation/off-medication, and on-stimulation/on-medication. RESULTS: Twenty-five PD patients with a 5-year median follow-up after surgery (range 3-7 years) were included (18 males; disease duration at surgery: 10.44 [SD 4.62] years; age at surgery: 58.40 [SD 5.73] years). In the off-stimulation/off-medication and on-stimulation/on-medication conditions, patients who spoke louder had also the greater acceleration of the trunk during gait; whereas in the on-stimulation/on-medication condition only, patients with the poorer voice quality were also the worst to perform the sit to stand and gait phases of the iTUG. Conversely, patients with the higher speech rate performed well in the turning and walking phases of the iTUG. CONCLUSIONS: This study underlines the presence of different correlations between treatment effects of speech and gait parameters in PD patients treated with bilateral STN-DBS. This may allow us to better understand the common pathophysiological basis of these alterations and to develop a more specific and tailored rehabilitation approach for axial signs after surgery.
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Estimulación Encefálica Profunda , Enfermedad de Parkinson , Núcleo Subtalámico , Masculino , Humanos , Persona de Mediana Edad , Enfermedad de Parkinson/terapia , Enfermedad de Parkinson/tratamiento farmacológico , Habla , Resultado del Tratamiento , MarchaRESUMEN
Idiopathic toe walking (ITW) is a gait deviation characterized by forefoot contact with the ground, sometimes observed in children, that alters ankle kinematics, possibly leading to health-related issues. When studying foot and ankle gait deviations, the adoption of a single-segment foot model entails a significant simplification of foot and ankle movement, and thus may potentially mask some important foot dynamics. Differences in ankle kinematics between single- (conventional gait model, PiG, or Davis) and multi-segment (Oxford foot model, OFM) foot models were investigated in children with ITW. Fourteen participants were enrolled in the study and underwent instrumented gait analysis. Children were asked to walk barefoot and while wearing a foot orthosis that modified the ankle movement pattern toward a more physiological one without blocking foot intrinsic motion. ITW gait abnormalities, e.g., the absence of heel rocker and the presence of anticipated forefoot rocker, were found/not found according to the foot model. Walking conditions significantly interacted with the foot model effect. Finally, the different characterization of gait abnormalities led to a different classification of ITW, with a possible impact on the clinical evaluation. Due to its closer adhesion to ankle anatomy and to its sensitivity to ITW peculiarities, OFM may be preferable for instrumented gait analysis in this population.
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Idiopathic toe walking (ITW) is a gait deviation characterized by forefoot contact with the ground and excessive ankle plantarflexion over the entire gait cycle observed in otherwise-typical developing children. The clinical evaluation of ITW is usually performed using optoelectronic systems analyzing the sagittal component of ankle kinematics and kinetics. However, in standardized laboratory contexts, these children can adopt a typical walking pattern instead of a toe walk, thus hindering the laboratory-based clinical evaluation. With these premises, measuring gait in a more ecological environment may be crucial in this population. As a first step towards adopting wearable clinical protocols embedding magneto-inertial sensors and pressure insoles, this study analyzed the performance of three algorithms for gait events identification based on shank and/or foot sensors. Foot strike and foot off were estimated from gait measurements taken from children with ITW walking barefoot and while wearing a foot orthosis. Although no single algorithm stands out as best from all perspectives, preferable algorithms were devised for event identification, temporal parameters estimate and heel and forefoot rocker identification, depending on the barefoot/shoed condition. Errors more often led to an erroneous characterization of the heel rocker, especially in shoed condition. The ITW gait specificity may cause errors in the identification of the foot strike which, in turn, influences the characterization of the heel rocker and, therefore, of the pathologic ITW behavior.
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Neurorehabilitation research in patients with traumatic brain injury (TBI) showed how vestibular rehabilitation (VR) treatments positively affect concussion-related symptoms, but no studies have been carried out in patients with severe TBI (sTBI) during post-acute intensive neurorehabilitation. We aimed at testing this effect by combining sensor-based gait analysis and clinical scales assessment. We hypothesized that integrating VR in post-acute neurorehabilitation training might improve gait quality and activity of daily living (ADL) in sTBI patients. A two-arm, single-blind randomized controlled trial with 8 weeks of follow-up was performed including thirty sTBI inpatients that underwent an 8-week rehabilitation program including either a VR or a conventional program. Gait quality parameters were obtained using body-mounted magneto-inertial sensors during instrumented linear and curvilinear walking tests. A 4X2 mixed model ANOVA was used to investigate session−group interactions and main effects. Patients undergoing VR exhibited improvements in ADL, showing early improvements in clinical scores. Sensor-based assessment of curvilinear pathways highlighted significant VR-related improvements in gait smoothness over time (p < 0.05), whereas both treatments exhibited distinct improvements in gait quality. Integrating VR in conventional neurorehabilitation is a suitable strategy to improve gait smoothness and ADL in sTBI patients. Instrumented protocols are further promoted as an additional measure to quantify the efficacy of neurorehabilitation treatments.
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Actividades Cotidianas , Lesiones Traumáticas del Encéfalo , Humanos , Método Simple Ciego , Resultado del Tratamiento , Marcha , Lesiones Traumáticas del Encéfalo/rehabilitaciónRESUMEN
Background: Idiopathic toe walking (ITW) is a gait deviation characterized by forefoot contact with the ground, possibly enhancing the risk of falling and causing Achilles' tendon shortening and psychological discomfort. Between possible treatments, foot orthosis may limit ITW when worn. With these premises, the effects of a novel foot orthosis (A.Dyn.O.®) on ankle function were analyzed in children with ITW during gait. Methods: Twenty-one children were recruited in the study after ITW diagnosis. At follow-up assessment after a habituation period of at least two weeks, participants walked in barefoot condition and while wearing A.Dyn.O.®. Kinetics and kinematics were derived from a multi-segment foot model using an optoelectronic system. Gait spatiotemporal parameters, ankle kinetic and kinematic and rockers timing were analyzed. Lastly, ITW severity was classified according to Alvarez classification. Differences between conditions were verified with paired t-test. Statistical parametric mapping was used to evaluate differences in the entire kinematic and kinetic waveforms. Findings: Wearing A.Dyn.O.®, step cadence was reduced, step length, stance phase and stride duration increased; physiological heel rocker was present, thus postponing the timing of ankle and forefoot rockers; ankle dorsiflexion angular excursion, range of motion, maximal dorsiflexor and plantarflexor moments together with maximal power absorption and production were all amplified. Interpretation: While wearing it, A.Dyn.O.® limited gait deviations typical of ITW and improved ITW severity classification for most of the participants. These findings suggest that the use of A.Dyn.O.® may assist ITW treatment, preventing children from toe walking and thus limiting its side effects.
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Anticipatory postural adjustments (APAs) prior to gait initiation are impaired in people with Parkinson's disease (PD), particularly in those who report Freezing of Gait (FOG). External cues can improve gait parameters in people with PD, but the effects of visual cues on gait initiation are poorly known. The study aimed to (i) assess differences, during gait initiation, between people with PD with (FOG+) and without FOG (FOG-) and healthy controls (HC), (ii) explore the effect of disease severity on gait initiation and (iii) investigate the acute effect of visual cueing on gait initiation and straight-ahead gait. Twenty FOG- and twenty FOG+, and eighteen HC participated in this study. Participants were asked to perform self-initiated gait with and without visual cues presented as transverse taped lines on the floor. Gait initiation and gait were characterized with wireless inertial measurement units. Results showed that FOG+ had smaller APAs than HC and FOG-; although no differences were detected between FOG+ and FOG- when taking into account disease severity. Significant correlations between MDS-UPDRS III scores and gait initiation/straight-ahead gait variables confirmed that differences between FOG+ and FOG- were driven by disease severity. In gait initiation, visual cues elicited different behaviors in people with and without PD. Particularly, people with PD showed smaller and longer APAs, whereas HC showed longer first step durations, compared to baseline. However, the adopted visual cues improved gait speed and stride length in all individuals. These results suggest that people with PD, despite the presence of FOG, utilize different motor strategies, compared to HC, to adapt to the new biomechanical requirements of gait initiation dictated by the visual cues.
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Trastornos Neurológicos de la Marcha , Enfermedad de Parkinson , Cognición , Señales (Psicología) , Marcha , HumanosRESUMEN
Wearable technologies are often indicated as tools that can enable the in-field collection of quantitative biomechanical data, unobtrusively, for extended periods of time, and with few spatial limitations. Despite many claims about their potential for impact in the area of injury prevention and management, there seems to be little attention to grounding this potential in biomechanical research linking quantities from wearables to musculoskeletal injuries, and to assessing the readiness of these biomechanical approaches for being implemented in real practice. We performed a systematic scoping review to characterise and critically analyse the state of the art of research using wearable technologies to study musculoskeletal injuries in sport from a biomechanical perspective. A total of 4952 articles were retrieved from the Web of Science, Scopus, and PubMed databases; 165 were included. Multiple study features-such as research design, scope, experimental settings, and applied context-were summarised and assessed. We also proposed an injury-research readiness classification tool to gauge the maturity of biomechanical approaches using wearables. Five main conclusions emerged from this review, which we used as a springboard to propose guidelines and good practices for future research and dissemination in the field.
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Enfermedades Musculoesqueléticas , Deportes , Dispositivos Electrónicos Vestibles , HumanosRESUMEN
Hammer throw is a discipline characterized by unique biomechanical features, which have often captured the interest of scientists and coaches in athletics. However, most studies have been published on technical journals for coaches and there are only few works on the biomechanical aspects of hammer throw in scientific literature. This narrative review provides a critical evaluation of the articles published in scientific and the most relevant technical journals with a particular focus on the biomechanical aspects that underlie the throwing technique and contribute to performance enhancement. The modern throwing technique has many elements in common with that used by the best throwers in the Eighties, underlying a limited development in the biomechanical understanding of throwing motion in recent years. This review analyses the ballistic and environmental aspects of the discipline as well as the motion of the center of mass of both the hammer and thrower. Furthermore, the orbital movement of the hammer and the forces involved in the throw are evaluated. This review emphasizes the kinematic and dynamic parameters that emerge as the most relevant to improve the throwing performance. Among these, linear release velocity appears to be a fundamental element. To maximize this variable, the athlete is required to accelerate the hammer by applying force. The curve of the time-tangential velocity of the hammer follows a trajectory very similar to that of the forces applied to the hammer-thrower system indicating a strong relationship between the two variables. The thrower uses the action of the leg muscles to gain momentum, which is then transferred to the hammer through the trunk and arm muscles, thus obtaining an increase of the linear release velocity. This review provides coaches with a critical analysis of the hammer throw technique, highlighting relevant factors for future development of training programmes. Our work reveals a substantial gap in the literature, particularly concerning the evaluation of fundamental key aspects of the throw such as the assessment of preliminary winds, the entry to the first turn and the definition of the rotation axes involved in the throw. A more in-depth analysis of these key elements is required to improve the understanding of the biomechanics of hammer throw.
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In children, motor competence (MC) and the amount of physical activity are tightly interconnected. In adults with Down syndrome (DS), MC has been poorly addressed, resulting in a limited understanding of the possibility to improve MC over time. Here, we aim to: (1) investigate MC in adults with DS by comparing them with a group of typically developed peers and (2) verify the effect of an adapted karate program on MC. Adults with DS (DSG; n = 57) and typically developed adults (TDG; n = 21) performed the Test of Gross Motor Development version 3 (TGMD-3). The total TGMD-3 score (TOTTGMD-3), the locomotor (LOCTGMD-3), and object control (OBJTGMD-3) scores were computed. After a 40 week adapted karate program, DSG (n = 37) underwent the post-training TGMD-3 assessment. Compared to TDG, DSG showed lower TOTTGMD-3 (DSG: 45.5 ± 17.3; TDG: 77.3 ± 9.5), LOCTGMD-3 (DSG: 22.2 ± 10.0; TDG: 36.2 ± 7.6) and OBJTGMD-3 (DSG: 23.3 ± 10.9; TDG: 41.1 ± 5.6). After the training, TOTTGMD-3, LOCTGMD-3 and OBJTGMD-3 increased by 35.6%, 30.0% and 40.7%, respectively. Our results suggest that MC acquisition does not evolve into a mature form in adulthood in individuals with DS. Moreover, a brief exposure to an adapted karate program induces an increase in motor competence in DS, even in adulthood.