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1.
Article in English | MEDLINE | ID: mdl-38791809

ABSTRACT

Accurate body temperature measurement is essential for monitoring and managing safety during outdoor activities. Physical activities are an essential consideration for public health, with sports taking up an important proportion of these. Athletes' performances can be directly affected by body temperature fluctuations, with overheating or hypothermia posing serious health risks. Monitoring these temperatures allows coaches and medical staff to make decisions that enhance performance and safety. Traditional methods, like oral, axillary, and tympanic readings, are widely used, but face challenges during intense physical activities in real-world environments. This study evaluated the agreement, correlation, and interchangeability of oral, axillary, and tympanic temperature measurements in outdoor exercise conditions. Systems developed for specific placements might generate different sensor readouts. Conducted as an observational field study, it involved 21 adult participants (11 males and 10 females, average age 25.14 ± 5.80 years) that underwent the Yo-Yo intermittent recovery test protocol on an outdoor court. The main outcomes measured were the agreement and correlation between temperature readings from the three methods, both before and after exercise. The results indicate poor agreement between the measurement sites, with significant deviations observed post-exercise. Although the Spearman correlation coefficients showed consistent temperature changes post-exercise across all methods, the standard deviations in the pairwise comparisons exceeded 0.67 °C. This study concluded that widely used temperature measurement methods are challenging to use during outdoor exercises and should not be considered interchangeable. This variability, especially after exercise, underscores the need for further research using gold standard temperature measurement methods to determine the most suitable site for accurate readings. Care should thus be taken when temperature screening is done at scale using traditional methods, as each measurement site should be considered within its own right.


Subject(s)
Body Temperature , Exercise , Humans , Male , Adult , Female , Young Adult , Mouth/physiology , Ear/physiology , Monitoring, Physiologic/methods , Monitoring, Physiologic/instrumentation
2.
BMJ Open ; 14(4): e081306, 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38684250

ABSTRACT

OBJECTIVE: To explore the experiences of healthcare professionals (HCPs) and parents of urine collection methods, to identify barriers to successful sampling and what could improve the process. DESIGN: Qualitative research, using individual semistructured interviews with HCPs and parents. The interviews were audiorecorded, transcribed and thematically analysed. SETTING: UK-based HCPs from primary and secondary care settings and parents with experience with urine collection in primary and/or secondary care settings. PARTICIPANTS: HCPs who were involved in aiding, supervising or ordering urine samples. Parents who had experience with urine collection in at least one precontinent child. RESULTS: 13 HCPs and 16 parents were interviewed. 2 participating HCPs were general practitioners (GPs), 11 worked in paediatric secondary care settings (8 were nurses and 3 were doctors). Two parents had children with underlying conditions where frequent urine collection was required to rule out infections.HCPs and parents reported that there were no straightforward methods of urine collection for precontinent children. Each method-'clean catch', urine bag and urine pad-had limitations and problems with usage. 'Clean catch', regarded as the gold standard by HCPs with a lower risk of contamination, often proved difficult for parents to achieve. Other methods had elevated risk of contamination but were more acceptable to parents because they were less challenging. Many of the parents expressed the need for more information about urine collection. CONCLUSIONS: Current methods of urine collection are challenging to use and may be prone to contamination. A new device is required to assist with urine collection in precontinent children, to simplify and reduce the stress of the situation for those involved. Parents are key partners in the process of urine collection with young children. Meeting their expressed need for more information could be an important way to achieve better-quality samples while awaiting a new device.


Subject(s)
Parents , Qualitative Research , Urine Specimen Collection , Humans , Parents/psychology , United Kingdom , Male , Female , Urine Specimen Collection/methods , Interviews as Topic , Attitude of Health Personnel , Child, Preschool , Infant , Adult , Child
3.
Front Neurol ; 14: 1260445, 2023.
Article in English | MEDLINE | ID: mdl-38020624

ABSTRACT

People living with mobility-limiting conditions such as Parkinson's disease can struggle to physically complete intended tasks. Intent-sensing technology can measure and even predict these intended tasks, such that assistive technology could help a user to safely complete them. In prior research, algorithmic systems have been proposed, developed and tested for measuring user intent through a Probabilistic Sensor Network, allowing multiple sensors to be dynamically combined in a modular fashion. A time-segmented deep-learning system has also been presented to predict intent continuously. This study combines these principles, and so proposes, develops and tests a novel algorithm for multi-modal intent sensing, combining measurements from IMU sensors with those from a microphone and interpreting the outputs using time-segmented deep learning. It is tested on a new data set consisting of a mix of non-disabled control volunteers and participants with Parkinson's disease, and used to classify three activities of daily living as quickly and accurately as possible. Results showed intent could be determined with an accuracy of 97.4% within 0.5 s of inception of the idea to act, which subsequently improved monotonically to a maximum of 99.9918% over the course of the activity. This evidence supports the conclusion that intent sensing is viable as a potential input for assistive medical devices.

4.
Sensors (Basel) ; 23(17)2023 Aug 26.
Article in English | MEDLINE | ID: mdl-37687902

ABSTRACT

In recent years, non-contact infrared thermometers (NCITs) and infrared thermography (IRT) have gained prominence as convenient, non-invasive tools for human body temperature measurement. Despite their widespread adoption in a range of settings, there remain questions about their accuracy under varying conditions. This systematic review sought to critically evaluate the performance of NCITs and IRT in body temperature monitoring, synthesizing evidence from a total of 72 unique settings from 32 studies. The studies incorporated in our review ranged from climate-controlled room investigations to clinical applications. Our primary findings showed that NCITs and IRT can provide accurate and reliable body temperature measurements in specific settings and conditions. We revealed that while both NCITs and IRT displayed a consistent positive correlation with conventional, contact-based temperature measurement tools, NCITs demonstrated slightly superior accuracy over IRT. A total of 29 of 50 settings from NCIT studies and 4 of 22 settings from IRT studies achieved accuracy levels within a range of ±0.3 °C. Furthermore, we found that several factors influenced the performance of these devices. These included the measurement location, the type of sensor, the reference and tool, individual physiological attributes, and the surrounding environmental conditions. Our research underscores the critical need for further studies in this area to refine our understanding of these influential factors and to develop standardized guidelines for the use of NCITs and IRT.


Subject(s)
Body Temperature , Thermometers , Humans , Climate , First Aid
5.
Biosensors (Basel) ; 13(5)2023 May 10.
Article in English | MEDLINE | ID: mdl-37232894

ABSTRACT

The reliable monitoring of heart rate during intense exercise is imperative to effectively manage training loads while providing insights from a healthcare perspective. However, current technologies perform poorly in contact sports settings. This study aims to evaluate the best approach for heart rate tracking using photoplethysmography sensors embedded into an instrumented mouthguard (iMG). Seven adults wore iMGs and a reference heart rate monitor. Several sensor placements, light sources and signal intensities were explored for the iMG. A novel metric related to the positioning of the sensor in the gum was introduced. The error between the iMG heart rate and the reference data was assessed to obtain insights into the effect of specific iMG configurations on measurement errors. Signal intensity was found to be the most important variable for error prediction, followed by the sensor light source, sensor placement and positioning. A generalized linear model combining an infrared light source, at an intensity of 5.08 mA, and a frontal placement high in the gum area resulted in a heart rate minimum error of 16.33%. This research shows promising preliminary results for the use of oral-based heart rate monitoring, but highlights the need for the careful consideration of sensor configurations within these systems.


Subject(s)
Photoplethysmography , Signal Processing, Computer-Assisted , Heart Rate/physiology , Photoplethysmography/methods , Algorithms , Monitoring, Physiologic
6.
Sensors (Basel) ; 23(2)2023 Jan 04.
Article in English | MEDLINE | ID: mdl-36679385

ABSTRACT

Technological advancements are enabling new applications within biomedical engineering. As a connection point between the outer environment and the human system, the oral cavity offers unique opportunities for sensing technologies. This paper systematically reviews the performance of measurement systems tested in the human oral cavity. Performance was defined by metrics related to accuracy and agreement estimation. A comprehensive search identifying human studies that reported on the accuracy or agreement of intraoral sensors found 85 research papers. Most of the literature (62%) was in dentistry, followed by neurology (21%), and physical medicine and rehabilitation (12%). The remaining papers were on internal medicine, obstetrics, and aerospace medicine. Most of the studies applied force or pressure sensors (32%), while optical and image sensors were applied most widely across fields. The main challenges for future adoption include the lack of large human trials, the maturity of emerging technologies (e.g., biochemical sensors), and the absence of standardization of evaluation in specific fields. New research should aim to employ robust performance metrics to evaluate their systems and incorporate real-world evidence as part of the evaluation process. Oral cavity sensors offer the potential for applications in healthcare and wellbeing, but for many technologies, more research is needed.


Subject(s)
Biomedical Engineering , Gravitation , Pregnancy , Female , Humans , Mouth
7.
J Biomech Eng ; 145(4)2023 04 01.
Article in English | MEDLINE | ID: mdl-36346198

ABSTRACT

Reliably and accurately estimating joint/segmental kinematics from optical motion capture data has remained challenging. Studies objectively characterizing human movement patterns have typically involved inverse kinematics and inverse dynamics techniques. Subsequent research has included scaled cadaver-based musculoskeletal (MSK) modeling for noninvasively estimating joint and muscle loads. As one of the ways to enhance confidence in the validity of MSK model predictions, the kinematics from the preceding step that drives such a model needs to be checked for agreement or compared with established/widely used models. This study rigorously compares the upper extremity (UE) joint kinematics calculated by the Dutch Shoulder Model implemented in the AnyBody Managed Model Repository (involving multibody kinematics optimization (MKO)) with those estimated by the Vicon Plug-in Gait model (involving single-body kinematics optimization (SKO)). Ten subjects performed three trials of (different types of) reaching tasks in a three-dimensional marker-based optical motion capture laboratory setting. Joint angles, processed marker trajectories, and reconstruction residuals corresponding to both models were compared. Scatter plots and Bland-Altman plots were used to assess the agreement between the two model outputs. Results showed the largest differences between the two models for shoulder, followed by elbow and wrist, with all root-mean-squared differences less than 10 deg (although this limit might be unacceptable for clinical use). Strong-to-excellent Spearman's rank correlation coefficients were found between the two model outputs. The Bland-Altman plots showed a good agreement between most of the outputs. In conclusion, results indicate that these two models with different kinematic algorithms broadly agree with each other, albeit with few key differences.


Subject(s)
Models, Anatomic , Musculoskeletal System , Upper Extremity , Humans , Upper Extremity/anatomy & histology , Cadaver , Musculoskeletal System/anatomy & histology , Biomechanical Phenomena , Motion Capture
8.
BDJ Open ; 8(1): 23, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-35915087

ABSTRACT

OBJECTIVE: This study aimed to determine the steady-state errors of oral-based temperature sensors, that are embedded in mouthguards, using a robust assessment process. MATERIALS AND METHODS: Four electronic boards with temperature sensors were encapsulated in mouthguards made from ethylene-vinyl acetate (EVA). The error and time to reach steady-state temperature were determined using a thermostatic water bath during three different conditions (34, 38.5 and 43 °C). Subsequently, a case study of one volunteer wearing the instrumented mouthguard is presented. RESULTS: The water bath tests showed that a mean absolute error of 0.2 °C was reached after a maximum of 690 s across all test conditions. The case study yielded an absolute error was 0.2 °C after 1110 s. CONCLUSION: These results show that an instrumented mouthguard with temperature sensing capabilities can yield a consistent steady-state error that is close to the clinical requirements across a range of temperatures. However, the time it takes to reach steady-state temperature needs to be considered for these systems to correctly interpret the outcomes.

9.
Sensors (Basel) ; 22(7)2022 Mar 29.
Article in English | MEDLINE | ID: mdl-35408218

ABSTRACT

Intent sensing-the ability to sense what a user wants to happen-has many potential technological applications. Assistive medical devices, such as prosthetic limbs, could benefit from intent-based control systems, allowing for faster and more intuitive control. The accuracy of intent sensing could be improved by using multiple sensors sensing multiple environments. As users will typically pass through different sensing environments throughout the day, the system should be dynamic, with sensors dropping in and out as required. An intent-sensing algorithm that allows for this cannot rely on training from only a particular combination of sensors. It should allow any (dynamic) combination of sensors to be used. Therefore, the objective of this study is to develop and test a dynamic intent-sensing system under changing conditions. A method has been proposed that treats each sensor individually and combines them using Bayesian sensor fusion. This approach was tested on laboratory data obtained from subjects wearing Inertial Measurement Units and surface electromyography electrodes. The proposed algorithm was then used to classify functional reach activities and compare the performance to an established classifier (k-nearest-neighbours) in cases of simulated sensor dropouts. Results showed that the Bayesian sensor fusion algorithm was less affected as more sensors dropped out, supporting this intent-sensing approach as viable in dynamic real-world scenarios.


Subject(s)
Algorithms , Intention , Bayes Theorem , Electromyography/methods , Humans
10.
Clin Biomech (Bristol, Avon) ; 69: 148-155, 2019 10.
Article in English | MEDLINE | ID: mdl-31352255

ABSTRACT

BACKGROUND: Thermal discomfort is prevalent among prosthesis users. This observational study of thirty unilateral lower-limb prosthesis users compared their skin temperatures and the thermal discomfort experienced during exercise between their residual and contralateral limbs. METHODS: Participants performed a 2-minute interval cycling exercise test. Skin temperature was measured at matched locations on each leg during the 1-minute rest intervals. Average rate-of-change in skin temperature was compared between legs using a repeated measures analysis of variance. Participants rated thermal discomfort on each leg before and after exercise, and a Wilcoxon signed-rank test was used to compare legs. Ordinal regression evaluated the relationship between the rate-of-change in temperature on the residual limb and the perceived thermal discomfort. FINDINGS: After exercise, thermal discomfort ranked higher on the amputated side (P = 0.007). On average, both legs cooled during exercise (P = 0.002), but the difference between legs was not significant. The rate-of change in skin temperature on the residual limb during exercise did not relate to the thermal discomfort experienced (odds ratio of 0.357). INTERPRETATION: These findings indicate that in this patient population, skin temperature does not explain the thermal discomfort experienced, and subjective thermal discomfort is inadequate for detecting thermoregulatory issues, with potential implications for long-term tissue health.


Subject(s)
Artificial Limbs , Exercise/physiology , Skin Temperature , Adult , Amputation Stumps/physiopathology , Amputees , Exercise Test , Female , Femur , Humans , Male , Middle Aged , Rest , Retrospective Studies , Surveys and Questionnaires , Temperature , Thermosensing , Tibia
11.
Ann Biomed Eng ; 47(8): 1725-1737, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31025132

ABSTRACT

The growing popularity of contact sports drives the requirement for better design of protective equipment, such as mouthguards. Smart mouthguards with embedded electronics provide a multitude of new ways to provide increased safety and protection to users. Characterisation of how electronic components embedded in typical mouthguard material, ethylene vinyl acetate (EVA), behave under typical sports impacts is crucial for future designs. A novel pendulum impact rig using a hockey ball disc impactor was developed to investigate impact forces and component failure. Two sets of dental models (aluminium and plastic padding chemical metal) were used to manufacture post-thermoformed mouthguards. Seven embedding conditions with varying thickness of EVA (1.5 and 3 mm) and locations of electrical components were tested. Component failures were observed in four out of seven test conditions, and the experimental failure forces at which the electrical component had a 50% chance of failure were reported for those cases. The experimental results showed that an EVA thickness of 3 mm surrounding the electrical component gives the most comprehensive protection even under extreme surface conformity. Computational models on surface conformity of EVA showed that a block of EVA with a minimum thickness of 1.5 mm was better at reducing stress concentration than a shell with an overall thickness of 1.5 mm. This study demonstrated that the thickness of a mouthguard is important when protecting electrical components from extreme dental surface conformity, furthermore the surface geometry should not be overlooked when considering electrical component safety for in-body wearables that are impact prone.


Subject(s)
Equipment Design , Mouth Protectors , Sports Equipment , Wearable Electronic Devices , Computer Simulation , Materials Testing , Polyvinyls
12.
Cognit Comput ; 9(6): 749-757, 2017.
Article in English | MEDLINE | ID: mdl-29242718

ABSTRACT

Multitasking is common in everyday life, but its effect on activities of daily living is not well understood. Critical appraisal of performance for both healthy individuals and patients is required. Motor activities during meal preparation were monitored in healthy individuals with a wearable sensor network during single and multitask conditions. Motor performance was quantified by the median frequencies (fm) of hand trajectories and wrist accelerations. The probability that multitasking occurred based on the obtained motor information was estimated using a Naïve Bayes Model, with a specific focus on the single and triple loading conditions. The Bayesian probability estimator showed task distinction for the wrist accelerometer data at the high and low value ranges. The likelihood of encountering a certain motor performance during well-established everyday activities, such as preparing a simple meal, changed when additional (cognitive) tasks were performed. Within a healthy population, the probability of lower acceleration frequency patterns increases when people are asked to multitask. Cognitive decline due to aging or disease might yield even greater differences.

13.
BMJ Open ; 7(12): e016891, 2017 12 21.
Article in English | MEDLINE | ID: mdl-29273650

ABSTRACT

OBJECTIVE: To evaluate the clinical efficacy and effectiveness of using 3D printing to develop medical devices across all medical fields. DESIGN: Systematic review compliant with Preferred Reporting Items for Systematic Reviews and Meta-Analyses. DATA SOURCES: PubMed, Web of Science, OVID, IEEE Xplore and Google Scholar. METHODS: A double-blinded review method was used to select all abstracts up to January 2017 that reported on clinical trials of a three-dimensional (3D)-printed medical device. The studies were ranked according to their level of evidence, divided into medical fields based on the International Classification of Diseases chapter divisions and categorised into whether they were used for preoperative planning, aiding surgery or therapy. The Downs and Black Quality Index critical appraisal tool was used to assess the quality of reporting, external validity, risk of bias, risk of confounding and power of each study. RESULTS: Of the 3084 abstracts screened, 350 studies met the inclusion criteria. Oral and maxillofacial surgery contained 58.3% of studies, and 23.7% covered the musculoskeletal system. Only 21 studies were randomised controlled trials (RCTs), and all fitted within these two fields. The majority of RCTs were 3D-printed anatomical models for preoperative planning and guides for aiding surgery. The main benefits of these devices were decreased surgical operation times and increased surgical accuracy. CONCLUSIONS: All medical fields that assessed 3D-printed devices concluded that they were clinically effective. The fields that most rigorously assessed 3D-printed devices were oral and maxillofacial surgery and the musculoskeletal system, both of which concluded that the 3D-printed devices outperformed their conventional comparators. However, the efficacy and effectiveness of 3D-printed devices remain undetermined for the majority of medical fields. 3D-printed devices can play an important role in healthcare, but more rigorous and long-term assessments are needed to determine if 3D-printed devices are clinically relevant before they become part of standard clinical practice.


Subject(s)
Models, Anatomic , Printing, Three-Dimensional , Treatment Outcome , Humans , Randomized Controlled Trials as Topic
14.
J Neurosci Methods ; 236: 148-56, 2014 Oct 30.
Article in English | MEDLINE | ID: mdl-25158318

ABSTRACT

BACKGROUND: Dendritic filopodia are highly motile and flexible protrusions that explore the surroundings in search for an appropriate presynaptic partner. Dendritic filopodia morphologically and functionally transform into postsynaptic dendritic spines, once the appropriate partner has been chosen. Therefore, proper formation of synapses depends on the dynamics of dendritic filopodia and spines. Thus, a rigorous assessment of dendrite filopodia behavior could be informative in providing a link between filopodia dynamics and synaptic development. NEW METHOD: In this paper, a tool for automated tracking of filopodia dynamics, the Filopodia-dynamics program (F-dynamics), will be described, tested and applied. The aim of this study is to validate the accuracy and reliability of F-dynamics and to test the program in live neurons. RESULTS: We demonstrate that filopodia dynamics can be reliably and accurately quantified using the F-dynamics program. In the present study, this program was used to successfully show that lithium treatment increases filopodia motility. COMPARISON WITH EXCITING METHODS: F-dynamics is the first analysis program that is able to determine dendritic filopodia dynamics automatically across both the longitudinal and lateral dimensions. CONCLUSION: Our data suggests that this analysis method can be used to differentiate between different experimental conditions and illustrates the potential of the program to measure pharmaceutical or genetic effects on filopodia dynamics.


Subject(s)
Cell Movement , Dendrites/physiology , Image Processing, Computer-Assisted/methods , Pattern Recognition, Automated/methods , Pseudopodia/physiology , Algorithms , Animals , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Cells, Cultured , Central Nervous System Agents/pharmacology , Dendrites/drug effects , Hippocampus/cytology , Hippocampus/drug effects , Hippocampus/physiology , Lithium Compounds/pharmacology , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Microscopy, Confocal/methods , Pseudopodia/drug effects , Rats, Sprague-Dawley , Reproducibility of Results , Software , Software Validation , Transfection
15.
PLoS One ; 9(2): e88080, 2014.
Article in English | MEDLINE | ID: mdl-24516583

ABSTRACT

Humans appear to be sensitive to relative small changes in their surroundings. These changes are often initially perceived as irrelevant, but they can cause significant changes in behavior. However, how exactly people's behavior changes is often hard to quantify. A reliable and valid tool is needed in order to address such a question, ideally measuring an important point of interaction, such as the hand. Wearable-body-sensor systems can be used to obtain valuable, behavioral information. These systems are particularly useful for assessing functional interactions that occur between the endpoints of the upper limbs and our surroundings. A new method is explored that consists of computing hand position using a wearable sensor system and validating it against a gold standard reference measurement (optical tracking device). Initial outcomes related well to the gold standard measurements (r = 0.81) showing an acceptable average root mean square error of 0.09 meters. Subsequently, the use of this approach was further investigated by measuring differences in motor behavior, in response to a changing environment. Three subjects were asked to perform a water pouring task with three slightly different containers. Wavelet analysis was introduced to assess how motor consistency was affected by these small environmental changes. Results showed that the behavioral motor adjustments to a variable environment could be assessed by applying wavelet coherence techniques. Applying these procedures in everyday life, combined with correct research methodologies, can assist in quantifying how environmental changes can cause alterations in our motor behavior.


Subject(s)
Hand/physiology , Monitoring, Physiologic , Motor Activity/physiology , Movement/physiology , Adult , Female , Humans
16.
Measurement (Lond) ; 46(7): 2193-2200, 2013 Aug.
Article in English | MEDLINE | ID: mdl-26594082

ABSTRACT

Long-term monitoring is of great clinical relevance. Accelerometers are often used to provide information about activities of daily living. The median frequency (fm) of acceleration has recently been suggested as a powerful parameter for activity recognition. However, compliance issues arise when people need to integrate activity recognition sensors into their daily lives. More functional placements should provide higher levels of conformity, but may also affect the quality and generalizability of the signals. How fm changes as a result of a more functional sensor placement remains unclear. This study investigates the agreement in fm for a sensor placed on the back with one in the pocket across a range of daily activities. The translational and gravitational accelerations are also computed to determine if the accelerometer should be fused with additional sensors to improve agreement. Twelve subjects were tested over four tasks and only the "vertical" x-axis showed a moderate agreement (Intraclass Correlation Coefficient of 0.54) after correction for outliers. Generalizability across traditional and functional sensor locations might therefore be limited. Differentiation of the signal into a translational and gravitational component decreased the level of agreement further, suggesting that combined information streams are more robust to changing locations then singular data streams. Integrating multiple sensor modalities to obtain specific components is unlikely to improve agreement across sensor locations. More research is needed to explore measurement signals of more user friendly sensor configurations that will lead to a greater clinical acceptance of body worn sensor systems.

17.
IEEE Trans Neural Syst Rehabil Eng ; 20(5): 617-25, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22695363

ABSTRACT

The objective of this study was to investigate reliability of transcranial magnetic stimulation (TMS) parameters for three coil systems; hand-held circular and figure-of-eight and navigated figure-of-eight coils. Stimulus response curves, intracortical inhibition (SICI) and facilitation (ICF) were studied in the right first dorsal interosseus muscle of 10 healthy adults. Each coil system was tested twice per subject. Navigation was conducted by a custom built system. Cortical excitability showed moderate-to-good reliability for the hand-held and navigated figure-of-eight coils (Intraclass correlation coefficients (ICCs) 0.55-0.89). The circular coil showed poor reliability for motor evoked potential (MEP) amplitude at 120% resting motor threshold (RMT; MEP(120)) and MEP sum (ICCs 0.09 & 0.48). Reliability for SICI was good for all coil systems when an outlier was removed (ICCs 0.87-0.93), but poor for ICF (ICCs < 0.3). The circular coil had a higher MEP(120) than the navigated figure-of-eight coil (p = 0.004). Figure-of-eight coils can be used confidently to investigate cortical excitability over time. ICF should be interpreted with caution. The navigation device frees the experimenter and enables tracking of the position of the coil and subject. The results help guide the choice of coil system for longitudinal measurements of motor cortex function.


Subject(s)
Evoked Potentials, Motor/physiology , Transcranial Magnetic Stimulation/instrumentation , Transcranial Magnetic Stimulation/methods , Transducers , Adult , Equipment Design , Equipment Failure Analysis , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity
18.
Physiol Meas ; 33(2): 287-96, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22273819

ABSTRACT

In terms of self-rated health, the most important activities of daily living are those involving mobility. Of these activities stair climbing is regarded as the most strenuous. A loss of stair climbing ability with age is normally associated with a loss of muscle strength and power, while other factors that influence muscle function, such as fatigue, are often not taken into account. So far no research has been published on how long-lasting fatigue affects activities of daily living, despite the fact that it has been repeatedly proven, in laboratory settings, to influence muscle force production over long periods of time. Technological advances in body sensor networks (BSNs) now provide a method to measure performance during complex real-life situations. In this study the use of a BSN was explored to investigate the effects of long-lasting fatigue on stair climbing performance in 20 healthy adults. Stair climbing performance was measured before and after a fatiguing protocol using a BSN. Performance was defined by temporal and spatial parameters. Long-lasting fatigue was successfully induced in all participants using an exercise protocol. The BSN showed that post-exercise fatigue did not influence stair climbing times (p > 0.2) and no meaningful changes in joint angles were found. No effect on overall stair climbing performance was found, despite a clear presence of long-lasting fatigue. This study shows that physiological paradigms can be further explored using BSNs. Ecological validity of lab-based measurements can be increased by combining them with BSNs.


Subject(s)
Electrical Equipment and Supplies , Exercise/physiology , Fatigue/physiopathology , Walking/physiology , Adult , Female , Humans , Male , Middle Aged , Young Adult
19.
Sensors (Basel) ; 12(12): 16695-709, 2012 Dec 05.
Article in English | MEDLINE | ID: mdl-23443394

ABSTRACT

There has been a rising interest in wearable and implantable biomedical sensors over the last decade. However, many technologies have not been integrated into clinical care, due to a limited understanding of user-centered design issues. Little information is available about these issues and there is a need to adopt more rigorous evidence standards for design features to allow important medical sensors to progress quicker into clinical care. Current trends in patient preferences need to be incorporated at an early stage into the design process of prospective clinical sensors. The first comprehensive patient data set, discussing mobile biomedical sensor technology, is presented in this paper. The study population mainly consisted of individuals suffering from arthritis. It was found that sensor systems needed to be small, discreet, unobtrusive and preferably incorporated into everyday objects. The upper extremity was seen as the favored position on the body for placement, while invasive placement yielded high levels of acceptance. Under these conditions most users were willing to wear the body-worn sensor for more than 20 h a day. This study is a first step to generate research based user-orientated design criteria's for biomedical sensors.


Subject(s)
Biomedical Technology/trends , Biosensing Techniques/trends , Prostheses and Implants/trends , Humans , Patients , Prospective Studies
20.
Dyn Med ; 8: 3, 2009 Apr 23.
Article in English | MEDLINE | ID: mdl-19389238

ABSTRACT

BACKGROUND: Assessments of stair climbing in real-life situations using an optical tracking system are lacking, as it is difficult to adapt the system for use in and around full flights of stairs. Alternatively, a portable system that consists of inertial measurement units (IMUs) can be used to collect anatomical joint angles during stair ascent. The purpose of this study was to compare the anatomical joint angles obtained by IMUs to those calculated from position data of an optical tracking device. METHODS: Anatomical joint angles of the thigh, knee and ankle, obtained using IMUs and an optical tracking device, were compared for fourteen healthy subjects. Joint kinematics obtained with the two measurement devices were evaluated by calculating the root mean square error (RMSE) and by calculating a two-tailed Pearson product-moment correlation coefficient (r) between the two signals. RESULTS: Strong mean correlations (range 0.93 to 0.99) were found for the angles between the two measurement devices, as well as an average root mean square error (RMSE) of 4 degrees over all the joint angles, showing that the IMUs are a satisfactory system for measuring anatomical joint angles. CONCLUSION: These highly portable body-worn inertial sensors can be used by clinicians and researchers alike, to accurately collect data during stair climbing in complex real-life situations.

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