Medical-Grade ECG Sensor for Long-Term Monitoring.

The recent trend in electrocardiogram (ECG) device development is towards wireless body sensors applied for patient monitoring. The ultimate goal is to develop a multi-functional body sensor that will provide synchronized vital bio-signs of the monitored user. In this paper, we present an ECG sensor for long-term monitoring, which measures the surface potential difference between proximal electrodes near the heart, called differential ECG lead or differential lead, in short. The sensor has been certified as a class IIa medical device and is available on the market under the trademark Savvy ECG. An improvement from the user's perspective-immediate access to the measured data-is also implemented into the design. With appropriate placement of the device on the chest, a very clear distinction of all electrocardiographic waves can be achieved, allowing for ECG recording of high quality, sufficient for medical analysis. Experimental results that elucidate the measurements from a differential lead regarding sensors' position, the impact of artifacts, and potential diagnostic value, are shown. We demonstrate the sensors' potential by presenting results from its various areas of application: medicine, sports, veterinary, and some new fields of investigation, like hearth rate variability biofeedback assessment and biometric authentication.

Dynamic and Static Assessment of Single-Leg Postural Control in Female Soccer Players.

PURPOSE/BACKGROUND: Various methods are available for assessment of static and dynamic postural stability. The primary purpose of this study was to investigate the relationship between dynamic postural stability as measured by the Star Excursion Balance Test (SEBT) and static postural sway assessment as measured by the TechnoBody™ Pro-Kin in female soccer players. A secondary purpose was to determine side-to-side symmetry in this cohort. METHODS: A total of 18 female soccer players completed testing on the SEBT and Technobody™ Pro-Kin balance device. Outcome measures were anterior, posterior medial, and posterior lateral reaches from the SEBT and center of pressure in the x- and y-axes as well as SD of movement in the forward/backward and medial/lateral directions from the force plate on left and right legs. Bivariate correlations were determined between the 8 measures. In addition, paired Wilcoxon signed-rank tests were performed to determine similarity between limb scores. RESULTS: All measures on both the SEBT and postural sway assessment were significantly correlated when comparing dominant with nondominant lower-extremities with the exception of SD of movement in both x- and y-axes. When correlating results of the SEBT with postural sway assessment, a significant correlation was found between the SEBT right lower-extremity posterior lateral reach (r = .567, P < .05) and summed SEBT (r = .486, P < .05) and the center of pressure in the y-axis. A significant correlation was also found on the left lower-extremity, with SD of forward/backward movement and SEBT posterior medial reach (r = -.511, P < .05). CONCLUSIONS: Dynamic postural tests and static postural tests provide different information to the overall assessment of balance in female soccer players. Relationship between variables differed based on the subject's lower-extremity dominance.

Assessment of the Postural Stability of Female and Male Athletes.

OBJECTIVE: Postural stability is often affected by sport-related injuries and subsequently evaluated during postinjury examinations. Intrinsic factors, however, may also affect postural control. We sought to compare the postural control of female and male athletes as measured simultaneously by (1) the modified balance error scoring system (mBESS) and (2) a video-force plate system. DESIGN: Cross-sectional study. SETTING: Sports injury prevention center. PARTICIPANTS: Pediatric, adolescent, and young adult athletes who performed mBESS during an injury prevention evaluation. INDEPENDENT VARIABLES: We compared the postural control of female and male athletes. We also accounted for independent variables associated with postural stability, including age, body mass index, and history of ankle injury, concussion, and migraine headache. MAIN OUTCOME MEASURES: Total errors committed during the mBESS and measurements derived from integrated kinematic and kinetic data obtained by a video-force plate system. Differences between males and females were tested using analysis of covariance. RESULTS: Participants (n = 409) ranged in age from 10 to 29 years (mean = 14.6 ± 2.8); 60% were female. No significant differences on mBESS were detected between females and males; however, female athletes demonstrated significantly better postural stability on the video-force plate analysis during double-leg (P = 0.03, d = 0.28), single-leg (P < 0.001, d = 0.62), and tandem stances (P < 0.001, d = 0.53) when compared with males. CONCLUSIONS: Uninjured female athletes demonstrate better postural stability on video-force plate analysis than their uninjured male counterparts. These findings provide an important information assistive to clinicians during interpretation of postinjury balance tests.

Smartphone and tablet apps for concussion road warriors (team clinicians): a systematic review for practical users.

BACKGROUND: Mobile technologies are steadily replacing traditional assessment approaches for the recognition and assessment of a sports concussion. Their ease of access, while facilitating the early identification of a concussion, also raises issues regarding the content of the applications (apps) and their suitability for different user groups. AIM: To locate and review apps that assist in the recognition and assessment of a sports concussion and to assess their content with respect to that of internationally accepted best-practice instruments. METHODS: A search of international app stores and of the web using key terms such as 'concussion', 'sports concussion' and variants was conducted. For those apps meeting the inclusion criteria, data were extracted on the platform, intended users and price. The content of each app was benchmarked to the Sport Concussion Assessment Tool 2 (SCAT2) and Pocket SCAT2 using a custom scoring scheme to generate a percentage compliance statistic. RESULTS: 18 of the 155 apps identified met the inclusion criteria. Almost all (16/18) were available on an iOS platform and only five required a payment to purchase. The apps were marketed for a wide range of intended users from medical professionals to the general public. The content of the apps varied from 0% to 100% compliance with the selected standard, and 'symptom evaluation' components demonstrated the highest level of compliance. CONCLUSIONS: The surge in availability of apps in an unregulated market raises concerns as to the appropriateness of their content for different groups of end users. The consolidation of best-practice concussion instruments now provides a framework to inform the development of future apps.

[Hyperbaric therapy and diving medicine - hyperbaric chambers in use]. / Hyperbare Therapie und Tauchmedizin - Druckkammer im Einsatz.

Hyperbaric oxygen therapy (HBOT) is a scientifically justified and internationally established therapy, which is however not well-known thus rarely used in Germany. During a HBOT, the ambient pressure is raised while the patient breathes 100% O2, causing tissue partial oxygen pressure (ptO2) to increase distinctly. Through that, various pressure- and O2-associated processes are initiated. Herein 3 case studies are described that illustrate the mechanism of action and the range of applications of HBOT.

Whole body vibration in sport: a critical review.

Whole body vibration training is a recent area of study in athletic conditioning, health and rehabilitation. This paper provides a review of the effectiveness of this type of training in sport. A search was conducted across several electronic databases and studies on effects of whole body vibration training on sport performance were reviewed. Thirteen articles were included in the final analysis. The following variables were considered: participants investigated (sex and age), characteristics of the vibration (frequency and amplitude), training (type of sport, exposure time and intensity, tests used, type of study, effects examined and results obtained). This review considers proposed neural mechanisms and identifies studies that have demonstrated the effectiveness of WBV in sports. It considers where WBV might act and suggests that vibration can be an effective training stimulus. Future studies should focus on evaluating the long-term effects of vibration training and identify optimum frequency and amplitude, improve strength and muscular performance.

Preparing for events for physically challenged athletes.

The participation in sports for physically challenged athletes continues to expand in multiple domains from recreational, novice, and competitive to elite competitions such as the Paralympics. Physically challenged athletes have various disabilities such as visual impairments, spinal cord injuries, amputations, cerebral palsy, or other neuromuscular impairments and have different levels of functional ability within these broad categories. The spectrum of medical illnesses and musculoskeletal injuries seen with sports is similar to that of able-bodied athletes; however medical teams caring for athletes with disabilities need to be familiar with medical risks such as skin breakdown, thermoregulation problems, dehydration, autonomic dysreflexia, infections, orthotic and prosthetic issues, and psychiatric comorbidities that may be encountered. The medical team preparation for events involving physically challenged athletes should include obtaining appropriate medical supplies, ensuring disability-compatible access to medical areas, and preparing for emergency extraction from adaptive equipment.

The games: what can the sports medicine community learn from raves?

Electronic dance music festivals, also known as raves, are increasing in popularity. Despite the occasional tragedy in the lay press regarding medical incidents at raves, such events are relatively safe when compared to other mass gatherings. While the medical usage rates are lower than rock concerts and marathons, there are many similarities to both types of events with regard to the types of injuries and medical complaints. This article may assist in planning medical support for raves in the future.

On the use of mobile inflatable hypoxic marquees for sport-specific altitude training in team sports.

BACKGROUND/AIM: With the evolving boundaries of sports science and greater understanding of the driving factors in the human performance physiology, one of the limiting factors has now become the technology. The growing scientific interest on the practical application of hypoxic training for intermittent activities such as team and racket sports legitimises the development of innovative technologies serving athletes in a sport-specific setting. METHODS: Description of a new mobile inflatable simulated hypoxic equipment. RESULTS: The system comprises two inflatable units-that is, a tunnel and a rectangular design, each with a 215 m(3) volume and a hypoxic trailer generating over 3000 Lpm of hypoxic air with FiO2 between 0.21 and 0.10 (a simulated altitude up to 5100 m). The inflatable units offer a 45 m running lane (width=1.8 m and height=2.5 m) as well as a 8 m × 10 m dome tent. FiO2 is stable within a range of 0.1% in normal conditions inside the tunnel. The air supplied is very dry-typically 10-15% relative humidity. CONCLUSIONS: This mobile inflatable simulated hypoxic equipment is a promising technological advance within sport sciences. It offers an opportunity for team-sport players to train under hypoxic conditions, both for repeating sprints (tunnel configuration) or small-side games (rectangular configuration).

London 2012 Paralympic swimming: passive drag and the classification system.

BACKGROUND: The key difference between the Olympic and Paralympic Games is the use of classification systems within Paralympic sports to provide a fair competition for athletes with a range of physical disabilities. In 2009, the International Paralympic Committee mandated the development of new, evidence-based classification systems. This study aims to assess objectively the swimming classification system by determining the relationship between passive drag and level of swimming-specific impairment, as defined by the current swimming class. METHODS: Data were collected on participants at the London 2012 Paralympic Games. The passive drag force of 113 swimmers (classes 3-14) was measured using an electro-mechanical towing device and load cell. Swimmers were towed on the surface of a swimming pool at 1.5 m/s while holding their most streamlined position. RESULTS: Passive drag ranged from 24.9 to 82.8 N; the normalised drag (drag/mass) ranged from 0.45 to 1.86 N/kg. Significant negative associations were found between drag and the swimming class (τ = -0.41, p < 0.01) and normalised drag and the swimming class (τ = -0.60, p < 0.01). The mean difference in drag between adjacent classes was inconsistent, ranging from 0 N (6 vs 7) to 11.9 N (5 vs 6). Reciprocal Ponderal Index (a measure of slenderness) correlated moderately with normalised drag (r(P) = -0.40, p < 0.01). CONCLUSIONS: Although swimmers with the lowest swimming class experienced the highest passive drag and vice versa, the inconsistent difference in mean passive drag between adjacent classes indicates that the current classification system does not always differentiate clearly between swimming groups.

Effects of Olympic-style taekwondo kicks on an instrumented head-form and resultant injury measures.

OBJECTIVE: The objective of this study was to assess the effect of taekwondo kicks and peak foot velocity (FVEL) on resultant head linear acceleration (RLA), head injury criterion (HIC15) and head velocity (HVEL). METHODS: Each subject (n=12) randomly performed five repetitions of the turning kick (TK), clench axe kick (CA), front leg axe kick, jump back kick (JB) and jump spinning hook kick (JH) at the average standing head height for competitors in their weight division. A Hybrid II Crash Test Dummy head was fitted with a protective taekwondo helmet and instrumented with a triaxial accelerometer and fixed to a height-adjustable frame. Resultant head linear acceleration, HVEL, FVEL data were captured and processed using Qualysis Track Manager. RESULTS: The TK (130.11 ± 51.67 g) produced a higher RLA than the CA (54.95 ± 20.08 g, p<0.001, d=1.84) and a higher HIC15 than the JH (672.74 ± 540.89 vs 300.19 ± 144.35, p<0.001, ES=0.97). There was no difference in HVEL of the TK (4.73 ± 1.67 m/s) and that of the JB (4.43 ± 0.78 m/s; p=0.977, ES<0.01). CONCLUSIONS: The TK is of concern because it is the most common technique and cause of concussion in taekwondo. Future studies should aim to understand rotational accelerations of the head.

The FIFA medical emergency bag and FIFA 11 steps to prevent sudden cardiac death: setting a global standard and promoting consistent football field emergency care.

Life-threatening medical emergencies are an infrequent but regular occurrence on the football field. Proper prevention strategies, emergency medical planning and timely access to emergency equipment are required to prevent catastrophic outcomes. In a continuing commitment to player safety during football, this paper presents the FIFA Medical Emergency Bag and FIFA 11 Steps to prevent sudden cardiac death. These recommendations are intended to create a global standard for emergency preparedness and the medical response to serious or catastrophic on-field injuries in football.

Outcomes from sudden cardiac arrest in US high schools: a 2-year prospective study from the National Registry for AED Use in Sports.

BACKGROUND: Sudden cardiac arrest (SCA) is the leading cause of death in athletes during exercise. The effectiveness of school-based automated external defibrillator (AED) programmes has not been established through a prospective study. METHODS: A total of 2149 high schools participated in a prospective observational study beginning 1 August 2009, through 31 July 2011. Schools were contacted quarterly and reported all cases of SCA. Of these 95% of schools confirmed their participation for the entire 2-year study period. Cases of SCA were reviewed to confirm the details of the resuscitation. The primary outcome was survival to hospital discharge. RESULTS: School-based AED programmes were present in 87% of participating schools and in all but one of the schools reporting a case of SCA. Fifty nine cases of SCA were confirmed during the study period including 26 (44%) cases in students and 33 (56%) in adults; 39 (66%) cases occurred at an athletic facility during training or competition; 55 (93%) cases were witnessed and 54 (92%) received prompt cardiopulmonary resuscitation. A defibrillator was applied in 50 (85%) cases and a shock delivered onsite in 39 (66%). Overall, 42 of 59 (71%) SCA victims survived to hospital discharge, including 22 of 26 (85%) students and 20 of 33 (61%) adults. Of 18 student-athletes 16 (89%) and 8 of 9 (89%) adults who arrested during physical activity survived to hospital discharge. CONCLUSIONS: High school AED programmes demonstrate a high survival rate for students and adults who suffer SCA on school campus. School-based AED programmes are strongly encouraged.

Prepared for sudden cardiac arrest? A cross-sectional study of automated external defibrillators in amateur sport.

INTRODUCTION: Sudden cardiac arrest (SCA) is a rare but tragic part of professional and amateur sport. Following multiple high profile deaths in professional sport over the past two decades, there has been a significant trend towards the widespread availability of automated external defibrillators (AEDs) at amateur sports grounds. OBJECTIVES: To examine the availability of AEDs in amateur sports clubs in Cork, Ireland, and to investigate club practices with respect to the purchase, accessibility, maintenance and use of AEDs. DESIGN: A cross-sectional survey of 218 amateur Gaelic Athletic Association (GAA), soccer and rugby clubs was conducted between July and September 2012. Club committee representatives answered a 22-point questionnaire. RESULTS: 126 GAA clubs and 28 soccer and 17 rugby (n=171) clubs were enrolled in this study. A total of 81.3% of amateur clubs own an AED. We estimate an AED-use rate of one AED use for every 54.5 years an AED is available. Almost 50% of club representatives thought the location of their club AED could be improved while 12.9% of clubs admitted to not maintaining their club AED on a regular basis. CONCLUSIONS: A large proportion of amateur clubs in Cork City and County own an AED. Many clubs engage in regular maintenance and storage of AEDs. However, this study identifies several areas for improvement in facilitating a secure chain of survival for players in the event of an SCA.

Sports prehospital-immediate care and spinal injury: not a car crash in sight.

The prehospital management of serious injury is a key skill required of pitch-side medical staff. Previously, specific training in sports prehospital-immediate care was lacking or not of a comparable standard to other aspects of emergency care. Many principles have been drawn from general prehospital care or in-hospital training courses. This article discusses sports prehospital-immediate care as a niche of general prehospital care, using spinal injury management as an illustration of the major differences. It highlights the need to develop the sport-specific prehospital evidence base, rather than relying exclusively on considerations relevant to prolonged immobilisation of multiply injured casualties from motor vehicle accidents, falls from height or burns.

Coronary artery abnormalities and sudden cardiac death.

Anomalous origin of a coronary artery (AOCA) can be associated with sudden cardiac death (SCD), particularly in young athletes. The diagnosis usually can be made by transthoracic echocardiography. In the case of patients for whom this method is not diagnostic, other methods are available including transesophageal echocardiography, cardiac magnetic resonance imaging (CMRI), and computed tomographic (CT) angiography. The decision to intervene is dependent on the type of lesion, the course of the coronary artery, its known association with SCD, and any symptoms present at the time of diagnosis. For patients without symptoms who have lesions less clearly associated with SCD [e.g., anomalous origin of the right coronary artery (AORCA)], the decision to intervene is more controversial. Further prospective studies hopefully will elucidate the optimum treatment pathway for such patients.

Primary prevention of sudden cardiac death of the young athlete: the controversy about the screening electrocardiogram and its innovative artificial intelligence solution.

The preparticipation screening for athlete participation in sports typically entails a comprehensive medical and family history and a complete physical examination. A 12-lead electrocardiogram (ECG) can increase the likelihood of detecting cardiac diagnoses such as hypertrophic cardiomyopathy, but this diagnostic test as part of the screening process has engendered considerable controversy. The pro position is supported by argument that international screening protocols support its use, positive diagnosis has multiple benefits, history and physical examination are inadequate, primary prevention is essential, and the cost effectiveness is justified. Although the aforementioned myriad of justifications for routine ECG screening of young athletes can be persuasive, several valid contentions oppose supporting such a policy, namely, that the sudden death incidence is very (too) low, the ECG screening will be too costly, the false-positive rate is too high, resources will be allocated away from other diseases, and manpower is insufficient for its execution. Clinicians, including pediatric cardiologists, have an understandable proclivity for avoiding this prodigious national endeavor. The controversy, however, should not be focused on whether an inexpensive, noninvasive test such as an ECG should be mandated but should instead be directed at just how these tests for young athletes can be performed in the clinical imbroglio of these disease states (with variable genetic penetrance and phenotypic expression) with concomitant fiscal accountability and logistical expediency in this era of economic restraint. This monumental endeavor in any city or region requires two crucial elements well known to business scholars: implementation and execution. The eventual solution for the screening ECG dilemma requires a truly innovative and systematic approach that will liberate us from inadequate conventional solutions. Artificial intelligence, specifically the process termed "machine learning" and "neural networking," involves complex algorithms that allow computers to improve the decision-making process based on repeated input of empirical data (e.g., databases and ECGs). These elements all can be improved with a national database, evidence-based medicine, and in the near future, innovation that entails a Kurzweilian artificial intelligence infrastructure with machine learning and neural networking that will construct the ultimate clinical decision-making algorithm.

Comparison of velocity and power output data derived from an inertial based system and an optical encoder during squat lifts in a weight room setting.

AIM: The purpose of this study was to assess a new wireless, light and portable inertial measurement system (FreePower; Sensorize, Rome, Italy), by comparing the measures of velocity and power it provides to the same measures derived from a high resolution optical encoder (Ergotest Technology a.s., Langesund, Norway). METHODS: Fifteen male tennis and soccer players performed back squat lifts at the Smith Machine at loads ranging from 30% to 90% of their established 1RM load. The two devices measured the kinematics of the barbell simultaneously. The mean and peak velocity of the barbell and the mean and peak power applied to the barbell-body system were extracted and used for the comparison. RESULTS: Measures of velocity and power, both in mean and peak values evidenced significant correlations (P<0.05) between the two systems. Linear regression r-squared values ranged from 0.978 for mean velocity to 0.993 for peak power, showing high-shared variance between the FreePower and the encoder values. Peak velocity, peak power and mean power values showed an absolute percentage difference of 2.8%, 3%, and 3.8%, respectively. The greatest discrepancy between the two systems was found in mean velocity values, where significantly lower values (P<0.05) were measured with the inertial system (-5.3%). CONCLUSION: The FreePower® inertial system can provide practitioners with measures of velocity and power that are consistent, within reasonable error limits, with a high resolution optical encoder, when it is used in a standard weight room setting and a significant number of lifts are included in the analysis.

Prehospital emergency removal of football helmets using two techniques.

OBJECTIVE: To compare the Eject Helmet Removal (EHR) System with manual football helmet removal. METHODS: This quasiexperimental counterbalanced study was conducted in a controlled laboratory setting. Thirty certified athletic trainers (17 men and 13 women; mean ± standard deviation age: 33.03 ± 10.02 years; height: 174.53 ± 12.04 cm; mass: 85.19 ± 19.84 kg) participated after providing informed consent. Participants removed a Riddell Revolution IQ football helmet from a healthy model two times each under two conditions: manual helmet removal (MHR) and removal with the EHR system. A six-camera, three-dimensional motion capture system was used to record range of motion (ROM) of the head. A digital stopwatch was used to time trials and to record a split time associated with EHR system bladder insertion. A modified Borg CR10 scale was used to measure the rating of perceived exertion (RPE). Mean values were created for each variable. Three pairwise t-tests with Bonferroni-corrected alpha levels tested for differences between time for removal, split time, and RPE. A 2 x 3 (condition x plane) totally within-subjects repeated-measures design analysis of variance (ANOVA) tested for differences in head ROM between the sagittal, frontal, and transverse planes. Analyses were performed using SPSS (version 18.0) (alpha = 0.05). RESULTS: There was no statistically significant difference in perceived difficulty between EHR (RPE = 2.73) and MHR (RPE = 2.55) (t(29) = 0.76; p = 0.45; d = 0.20). Manual helmet removal was, on average, 28.95 seconds faster than EHR (t(29) = 11.44; p < 0.001). Head ROM was greater during EHR compared with MHR in the sagittal (t(29) = 4.57; p < 0.001), frontal (t(29) = 5.90; p < 0.001), and transverse (t(29) = 8.34; p < 0.001) planes. Head ROM was also greater during the helmet-removal portion of EHR in the frontal (t(29) = 4.44; p < 0.001) and transverse (t(29) = 5.99; p < 0.001) planes, compared with MHR. Regardless of technique, sagittal-plane head ROM was greater than frontal- and transverse-plane movements (F(2,58) = 241.47; p < 0.001). CONCLUSIONS: Removing a helmet manually is faster and creates slightly less motion than removing a helmet using the Eject system. Both techniques were equally easy to use. Future research should analyze the performance of the Eject system in other styles of football helmets and in helmets used in other sports such as lacrosse, motorsports, and ice hockey.

A wearable system to assess risk for anterior cruciate ligament injury during jump landing: measurements of temporal events, jump height, and sagittal plane kinematics.

The incidence of anterior cruciate ligament (ACL) injury remains high, and there is a need for simple, cost effective methods to identify athletes at a higher risk for ACL injury. Wearable measurement systems offer potential methods to assess the risk of ACL injury during jumping tasks. The objective of this study was to assess the capacity of a wearable inertial-based system to evaluate ACL injury risk during jumping tasks. The system accuracy for measuring temporal events (initial contact, toe-off), jump height, and sagittal plane angles (knee, trunk) was assessed by comparing results obtained with the wearable system to simultaneous measurements obtained with a marker-based optoelectronic reference system. Thirty-eight healthy participants (20 male and 18 female) performed drop jumps with bilateral and unilateral support landing. The mean differences between the temporal events obtained with both systems were below 5 ms, and the precisions were below 24 ms. The mean jump heights measured with both systems differed by less than 1 mm, and the associations (Pearson correlation coefficients) were above 0.9. For the discrete angle parameters, there was an average association of 0.91 and precision of 3.5° for the knee flexion angle and an association of 0.77 and precision of 5.5° for the trunk lean. The results based on the receiver-operating characteristic (ROC) also demonstrated that the proposed wearable system could identify movements at higher risk for ACL injury. The area under the ROC plots was between 0.89 and 0.99 for the knee flexion angle and between 0.83 and 0.95 for the trunk lean. The wearable system demonstrated good concurrent validity with marker-based measurements and good discriminative performance in terms of the known risk factors for ACL injury. This study suggests that a wearable system could be a simple cost-effective tool for conducting risk screening or for providing focused feedback.