Morteza Khodaee

Epidemiology of Stress Fracture Injuries Among US High School Athletes, 2005-2006 Through 2012-2013

Background: High school athletes in the United States sustain millions of injuries annually, approximately 10% of which are fractures. However, there is no clear estimate of the number of stress fractures sustained by high school athletes annually despite reports that stress fractures account for 0.7% to 20% of injuries seen in sports medicine clinics. This suggests a high utilization of resources for a potentially preventable injury. In addition, stress fractures have been associated with low energy availability and disordered eating in young athletes, highlighting the importance of early recognition and intervention. Purpose: To investigate stress fracture rates and patterns in a large national sample of US high school athletes. Study Design: Descriptive epidemiologic study. Methods: Data from High School RIO (Reporting Information Online), a national sports injury surveillance study, were analyzed to describe rates and patterns of stress fracture injury sustained from 2005-2006 through 2012-2013, across sports and by sex. Results: From 2005-2006 through 2012-2013, a total of 51,773 injuries were sustained during 25,268,873 athlete-exposures, of which 389 (0.8%) were stress fractures, resulting in an overall stress fracture rate of 1.54 per 100,000 athlete-exposures. Rates per 100,000 athlete-exposures were highest in girls’ cross country (10.62), girls’ gymnastics (7.43), and boys’ cross country (5.42). In sex-comparable sports, girls sustained more stress fractures (63.3%) than did boys (36.7%) and had higher rates of stress fracture (2.22 vs 1.27; rate ratio, 1.75; 95% CI, 1.38-2.23). The most commonly injured sites were the lower leg (40.3% of all stress fractures), foot (34.9%), and lower back/lumbar spine/pelvis (15.2%). Management was nonsurgical in 98.7% of the cases, and 65.3% of injuries resulted in ≥3 weeks of time loss, medical disqualification, or an end to the season before athletes could return to play. Conclusion: Although a rare injury, stress fractures cause considerable morbidity for high school athletes of both sexes. Future research should evaluate risks of stress fractures to drive development of targeted prevention efforts.

Medical Services at Ultra-Endurance Foot Races in Remote Environments: Medical Issues and Consensus Guidelines

An increasing participation in ultra-endurance foot races is cause for greater need to ensure the presence of appropriate medical care at these events. Unique medical challenges result from the extreme physical demands these events place on participants, the often remote settings spanning broad geographical areas, and the potential for extremes in weather conditions and various environmental hazards. Medical issues in these events can adversely affect race performance, and there is the potential for the presentation of life-threatening issues such as exercise-associated hyponatremia, severe altitude illnesses, and major trauma from falls or animal attacks. Organization of a medical support system for ultra-endurance foot races starts with a determination of the level of medical support that is appropriate and feasible for the event. Once that is defined, various legal considerations and organizational issues must be addressed, and medical guidelines and protocols should be developed. While there is no specific or universal standard of medical care for ultra-endurance foot races since a variety of factors determine the level and type of medical services that are appropriate and feasible, the minimum level of services that each event should have in place is a plan for emergency transport of injured or ill participants, pacers, spectators and event personnel to local medical facilities.

Duration of breastfeeding, daycare, and physician visits among infants 6 months and younger.

PURPOSE To describe the association between duration of breastfeeding and an illness requiring a visit to a health care provider within the past 30 days (IRHP) among infants </= 6 months. METHODS Participants were breastfeeding women who delivered at a birthing center in suburban Detroit, Michigan and women employed by a company in Omaha, Nebraska. Subjects were interviewed by telephone at 3,6,9, and 12 weeks postpartum and by mailed questionnaire at 6 months postpartum. RESULTS Of the 674 breastfeeding women, 233 (34.5%) reported an IRHP. An IRHP was more likely among infants attending daycare (RR = 1.60; 95% CI 1.30, 1.96). There was an interaction between duration of breastfeeding, the number of children in the household, and IRHP (p < 0.0001). For firstborn children, each additional week of breastfeeding decreased the likelihood of an IRHP by 4%. An increased duration of breastfeeding was not significantly protective against an IRHP for infants living with additional children in the household. CONCLUSIONS Breastfeeding offers protection against an IRHP among firstborn children. Having additional children in the household or attending daycare outside of the home may diminish these benefits.

Common ultramarathon injuries and illnesses: race day management.

Participation in ultramarathons has become increasingly popular especially among nonelite athletes. Ultramarathons have a wide spectrum of race characteristics from the variety of distances to environmental factors. Ultramarathons continue to attract a relatively small number of participants who on average are more experienced than marathon runners. There are limited epidemiologic studies on common ultramarathon injuries and illnesses. Musculoskeletal and dermatologic problems are very common among ultramarathoners. Each ultramarathon is unique, and medical directors should try to establish an injury surveillance system in order to be better prepared for possible medical conditions. The focus of this article is on the evaluation and management of common medical conditions encountered during ultramarathons.

Ephedrine and other stimulants as ergogenic aids.

Several recreational, prescription, and illicit drugs have psychotropic effects that may be perceived to be ergogenic. The ephedra alkaloids have received recent attention for their wide use by athletes and their potential serious side effects, despite the lack of evidence regarding any ergogenic or performance benefit. Some prescription drugs (eg, methylphenidate and bupropion) raise complex issues regarding their appropriate therapeutic use in athletes. Recreational drugs, some of which are illegal (eg, cocaine), are commonly used by athletes and cause a wide range of potentially ergolytic effects. In total, these drugs are important for their frequent use, the frequency with which they are mentioned in the media, and their potential for causing significant adverse effects.

Low mean level sustained and intermittent grip exertions: Influence of age on fatigue and recovery

The goal of this study was to quantify localised muscle fatigue resulting from low mean levels of exertion in younger (< 40 years) and older (>50 years) adults. Fatigue, elicited in the finger flexor muscles by intermittent (10% mean maximum voluntary contraction (MVC)) and sustained (8% MVC) handgrip exercises, was quantified by a muscle twitch force response before, immediately after and during 3 h following exercise. Despite greater mean loads, recovery time was shorter following intermittent than sustained contractions, which suggests that recovery from fatigue is more sensitive to rest within the work cycle than mean work. The more pronounced effects for younger than older individuals following the sustained exertion indicate that changes in muscle fibre type composition might predispose older individuals to be more resistant to fatigue resulting from sustained contractions of low level. Performing hand exertion tasks requiring low mean force levels contributes to similar long-lasting fatigue effects regardless of gender and age. Intermittent periods of complete rest reduce muscle fatigue. Since fatigue was not perceived during recovery from the tested sustained and intermittent contractions, subjective evaluations may not be a reliable indicator of localised muscle fatigue.

Athletes at High Altitude

Context: Athletes at different skill levels perform strenuous physical activity at high altitude for a variety of reasons. Multiple team and endurance events are held at high altitude and may place athletes at increased risk for developing acute high altitude illness (AHAI). Training at high altitude has been a routine part of preparation for some of the high level athletes for a long time. There is a general belief that altitude training improves athletic performance for competitive and recreational athletes. Evidence Acquisition: A review of relevant publications between 1980 and 2015 was completed using PubMed and Google Scholar. Study Design: Clinical review. Level of Evidence: Level 3. Results: AHAI is a relatively uncommon and potentially serious condition among travelers to altitudes above 2500 m. The broad term AHAI includes several syndromes such as acute mountain sickness (AMS), high altitude pulmonary edema (HAPE), and high altitude cerebral edema (HACE). Athletes may be at higher risk for developing AHAI due to faster ascent and more vigorous exertion compared with nonathletes. Evidence regarding the effects of altitude training on athletic performance is weak. The natural live high, train low altitude training strategy may provide the best protocol for enhancing endurance performance in elite and subelite athletes. High altitude sports are generally safe for recreational athletes, but they should be aware of their individual risks. Conclusion: Individualized and appropriate acclimatization is an essential component of injury and illness prevention.

Epidemiology of High School Sports-Related Injuries Resulting in Medical Disqualification 2005-2006 Through 2013-2014 Academic Years

Background: Although rare, season- or career-ending injuries in young athletes are concerning because they can result in time lost from sport participation and school, social costs, and economic costs of medical care. Purpose: To describe rates and patterns of medically disqualifying (MDQ) injuries among United States high school athletes overall and by sport, sex, type of athletic activity, and mechanism. Study Design: Descriptive epidemiological study. Methods: Sports-related injury data on high school athletes were collected during the 2005-2006 through 2013-2014 academic years from a large national sample of United States high schools via High School Reporting Information Online (RIO). MDQ injuries were defined as season- or career-ending injuries. Results: From 2005-2006 through 2013-2014, High School RIO captured 59,862 total injuries including 3599 MDQ injuries (6.0% of all injuries). Most MDQ injuries (60.4%) occurred in competition. Football had the highest injury rate (26.5 per 100,000 athlete-exposures), followed by gymnastics (18.6) and wrestling (17.9). MDQ injury rates were higher among girls in the sex-comparable sports of basketball (rate ratio [RR], 1.6; 95% CI, 1.3-2.0), cross-country (RR, 2.6; 95% CI, 1.0-7.5), soccer (RR, 1.6; 95% CI, 1.3-1.9), and track and field (RR, 2.6; 95% CI, 1.7-4.0). Player-player contact (48.2%) was the most common MDQ injury mechanism. The most commonly injured body site was the knee (33.7%). The most common MDQ injury diagnosis was sprains/strains (35.9%); the most common specific MDQ injury was knee sprains/strains (25.4%), with the anterior cruciate ligament being the most commonly injured knee structure. Among boys, fracture was the most common diagnosis in 3 sports, and sprain/strain was the most common in 6 sports. Among girls, sprain/strain was the most common diagnosis in 9 sports, and fracture was the most common only in softball. Conclusion: MDQ injuries vary by sport, sex, and type of athletic activity and occur most frequently as a result of player-player contact. These findings should prompt additional research into the development, implementation, and evaluation of targeted injury prevention efforts.

Exercise-Associated Hyponatremia in an Ultra-Endurance Mountain Biker A Case Report

Symptomatic exercise-associated hyponatremia (EAH), which is relatively common among marathon runners, is an uncommon event among ultra-endurance athletes. A 44-year-old man presented to the emergency department with increased thirst after successfully completing a 100-mile mountain bike race in Leadville, Colorado. Initial laboratory tests revealed a blood sodium level of 116 mEq/L. The primary etiologic factor in EAH is fluid consumption in excess of fluid losses in prolonged exertion. Early diagnosis and management is crucial to prevent cerebral and pulmonary edema.

Effects of Running an Ultramarathon on Cardiac, Hematologic, and Metabolic Biomarkers.

Serum biomarkers fluctuate as a result of running marathons, but their changes during ultramarathons have not been adequately studied. We collected blood samples from 20 participants before and 21 participants after the 161-km ultramarathon in Leadville, Colorado in August 2013. Using a portable analyzer, we measured cardiac troponin I (cTnl), hematologic, and metabolic biomarkers. Out of 10 runners for whom we collected both pre- and post-race samples, 8 were able to successfully complete the race. Mean cTnl increased from 0.001 to 0.047 ng/mL (p=0.005). Mean sodium decreased from 141 to 138 mmol/L (p <0.01). However, all runners had a sodium of ≥135 mmol/L post-race (reference range 138-146 mmol/L). Mean creatinine increased from 0.93 to 1.17 mg/dL (p <0.05). Only one out of 10 runners had an abnormal creatinine level of 1.8 mg/dL post-race (reference range 0.6-1.3 mg/dL). The other parameters did not reach statistical significance. Analyzing the samples from 21 runners after the race revealed that runners who finished the race in faster time had higher cTnl levels compared to those who finished the race close to the 30-hour cut-off finish time (P=0.005). Running an ultramarathon caused significant changes in cardiac and metabolic parameters. Ultramarathon running intensity and finish time may have effects on post-race cTnl level.