Pierre A. d’Hemecourt

Exertional dysnatremia in collapsed marathon runners: a critical role for point-of-care testing to guide appropriate therapy.

Dysnatremia may cause life-threatening encephalopathy in marathon runners. Hypernatremia and exercise-associated hyponatremia (EAH) may manifest with mental status changes and, if untreated, progress to coma and death. We reviewed the on-site blood sodium testing and treatment in collapsed runners at the finish-line medical tent at the Boston marathons from 2001 through 2008. Dysnatremia was diagnosed in 429 (32.5%) of 1,319 collapsed runners. Hypernatremia was present in 366 (27.7%) and hyponatremia in 63 (4.8%). Hypernatremic runners unable to drink fluids were treated with intravenous normal (0.9%) saline. Hyponatremic runners with seizures or coma received intravenous hypertonic (3%) saline. Sixteen runners with EAH able to drink a concentrated oral hypertonic solution recovered within 30 minutes. Based on on-site sodium testing, dysnatremic runners were treated with appropriate intravenous fluids according to validated standards of care. Hyponatremic runners able to drink an oral hypertonic solution recovered promptly.

Myocardial Adaptations to Recreational Marathon Training Among Middle-Aged Men

Background—Myocardial adaptations to exercise have been well documented among competitive athletes. To what degree cardiac remodeling occurs among recreational exercisers is unknown. We sought to evaluate the effect of recreational marathon training on myocardial structure and function comprehensively. Methods and Results—Male runners (n=45; age, 48±7 years; 64% with ≥1 cardiovascular risk factor) participated in a structured marathon-training program. Echocardiography, cardiopulmonary exercise testing, and laboratory evaluation were performed pre and post training to quantify changes in myocardial structure and function, cardiorespiratory fitness, and traditional cardiac risk parameters. Completion of an 18-week running program (25±9 miles/wk) led to increased cardiorespiratory fitness (peak oxygen consumption, 44.6±5.2 versus 46.3±5.4 mL/kg per minute; P<0.001). In this setting, there was a significant structural cardiac remodeling characterized by dilation of the left ventricle (end-diastolic volume, 156±26 versus 172±28 mL, P<0.001), right ventricle (end-diastolic area=27.0±4.8 versus 28.6±4.3 cm2; P=0.02), and left atrium (end-diastolic volume, 65±19 versus 72±19; P=0.02). Functional adaptations included increases in both early (E′=12.4±2.5 versus 13.2±2.0 cm/s; P=0.007) and late (A′=11.5±1.9 versus 12.2±2.1 cm/s; P=0.02) left ventricular diastolic velocities. Myocardial remodeling was accompanied by beneficial changes in cardiovascular risk factors, including body mass index (27.0±2.7 versus 26.7±2.6 kg/m2; P<0.001), total cholesterol (199±33 versus 192±29 mg/dL; P=0.01), low-density lipoprotein (120±29 versus 114±26 mg/dL; P=0.01), and triglycerides (100±52 versus 85±36 mg/dL; P=0.02). Conclusions—Among middle-aged men, recreational marathon training is associated with biventricular dilation, enhanced left ventricular diastolic function, and favorable changes in nonmyocardial determinants of cardiovascular risk. Recreational marathon training may, therefore, serve as an effective strategy for decreasing incident cardiovascular disease.

Effect of WBGT Index Measurement Location on Heat Stress Category Classification.

UNLABELLEDnThe location of the wet bulb globe temperature (WBGT) index measurement may affect heat stress flag category classification.nnnPURPOSEnThis study aimed to compare WBGT measurements at three locations along the Boston Marathon race course and compare WBGT estimates for meteorological stations and 72-h advanced WBGT forecasts.nnnMETHODSnWBGT was measured hourly from 1000 to 1400 h at approximately 7 km, approximately 18 km, and approximately 30 km on the Boston Marathon race course. Simultaneous WBGT estimates were made for two meteorological stations southeast of the course via a commercial online system, which also provided 72-h advanced forecasts.nnnRESULTSnThe measurement difference (mean ± SD) among course locations was 0.2°C ± 1.8°C WBGT (ANOVA, P > 0.05). The difference between course and stations was 1.9°C ± 2.4°C WBGT (t-test, P < 0.05). Station values underestimated (n = 98) or overestimated (n = 13) course values by >3°C WBGT (>0.5 flag category) in 111 of 245 paired comparisons (45%). Higher black globe and lower wet bulb temperatures explained over- and underestimates, respectively. Significant underestimates of WBGT resulted in misclassification of green (labeled white) and black (labeled red) course flag categories (χ2, P < 0.05). Forecast data significantly underestimated red (labeled amber) and black (labeled red) course flag categories.nnnCONCLUSIONSnDifferences in WBGT index along 23 km of the Boston Marathon race route can be small enough to warrant single measurements. However, significant misclassification of flag categories occurred using WBGT estimates for meteorological stations; thus, local measurements are preferred. If the relation between station WBGT forecasts and the race sites can be established, the forecast WBGT values could be corrected to give advanced warning of approximate flag conditions. Similar work is proposed for other venues to improve heat stress monitoring.

Association between coping skills, past injury and hip pain and function in adolescent elite female ballet dancers

ABSTRACT Objectives: The purpose of this study was to investigate the relationship between coping skills and current hip pain and function scores in ballet dancers. Secondly, we examined the relationship between coping skills and past injuries. Thirdly, we investigated the association between past injuries and current pain and function scores. Methods: This was a cross-sectional observational study. Twenty-six young elite female dancers (mean age 15.9 years, range 14–17 years) participated. Participants completed surveys indicating past injury history, rating pain and function on the short International Hip Outcome Tool (iHOT-12), and assessing coping skills on the Athletic Coping Skills Inventory Score (ACSI-28). Independent t-tests, Cohen’s d, effect size, chi-square and correlation coefficient and determination analyses were conducted. Results: There was no significant relationship between iHOT-12 scores and ACSI-28 scores (r = −0.250, p = 0.087). There was no significant difference (p = 0.289) in past injuries comparing those with ACSI-28 scores above and below the mean ACSI-28. A significant moderate negative correlation was detected between both iHOT-12 scores and total past injuries (r = −0.609, p < 0.001), and iHOT-12 scores and past non-hip injuries (r = −0.628, p < 0.001). Conclusion: Past injuries may influence current hip pain and function in young female dancers. Correlation determination (r2) indicated that 37% of current pain and function scores were explained by total past injuries in a small group of young high-level ballet dancers. Further research should engage a prospective design to investigate the predictive ability of findings.

Ultrasound examination and patellar tendinopathy scores in asymptomatic college jumpers

ABSTRACT Objective: To investigate the prevalence of hypoechoic areas by US and its’ association with VISA-P scores among asymptomatic jumpers while highlighting sex comparisons. Design: Cross-sectional study. Setting: Pre-participation exam at a National Collegiate Athletic Association (NCAA) division I college. Participants: Thirty-one college athletes who engage in jumping sports. Main outcome measures: Hypoechoic images of patellar tendon captured by ultrasound examination were compared to a self-reported knee functional survey, the Victorian Institute of Sport Assessment for patellar tendinopathy (VISA-P) scale (0–100). Results: With a total of 31 athletes (13 males and 18 females), prevalence rate of the hypoechoic areas of patellar tendon was 19.4% (6/31) in the right knee and 29.0% (9/31) in the left knee. There was no proportional difference in a comparison of prevalence rate of hypoechoic area [(+) or (−)] by sex in either right or left knee. The VISA-P scores were significantly lower in US (+) than US (−) in the right knee (p = 0.003, Cohen’s d = 1.675), but not the left knee (p = 0.250, Cohen’s d = 0.512). The receiver operating characteristics curve analysis indicated the most sensitive and specific VISA-P values based on status [(+) or (−)] of hypoechoic area was 89.5 with 86.4% and 77.7% of sensitivity and specificity. Conclusion: In short, hypoechoic areas were detected by US examination among self-reported asymptomatic jumpers. There was an association between hypoechoic areas and VISA-P scores in the right knee, but not in left knee. VISA-P scores may be used as a screening tool for the presence of hypoechoic areas.

Running mechanics of females with bilateral compartment syndrome

[Purpose] Primary purpose was to compare running mechanics between healthy runners and runners with chronic exertional compartment syndrome (CECS) including overstride angles, ankle dorsiflexion (DF) angles, and foot strike patterns. The secondary purpose was to analyze the association between the overstride angles and ankle DF angles. [Participants and Methods] Running images of 7 female runners with bilateral CECS patients were captured at a time of the medical examination. Their running images were compared with gender, age, and body mass index matched 31 healthy control runners. [Results] The bilateral CECS female runners have a propensity of running with significantly greater overstride and ankle DF angles than the healthy female runners. There were no foot strike differences between the two cohorts. There were a non-significant, poor relationship between overstride and ankle DF angles in the healthy female runners while a significant, strong association was found between overstride and ankle DF angles in the bilateral CECS female runners. [Conclusion] Compared to healthy female runners, bilateral CECS female runners demonstrated different running mechanics including greater overstride and ankle DF angles. The two variables were strongly associated with each other in bilateral CECS female runners, but not in healthy female runners. This may potentially contribute to the mechanism of CECS development.

Bony Morphology of Femoroacetabular Impingement in Young Female Dancers and Single-Sport Athletes

Background: Femoroacetabular impingement (FAI) is a painful and limiting condition of the hip that is often seen in young athletes. Previous studies have reported a higher prevalence of this disorder in male athletes, but data on the structural morphology of adolescent and young adult female athletes, specifically those involved in dance, are lacking. Purpose: (1) To investigate the radiographic morphology of FAI deformities in adolescent and young adult female single-sport dance and nondance athletes and (2) to examine the differences in the radiographic findings between these 2 groups. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A retrospective chart review of 56 female single-sport athletes 10 to 21 years of age with a diagnosis of FAI within a single-sports medicine division of a pediatric academic medical center was performed. Acetabular index (AI), lateral center-edge angle (LCEA), crossover sign, and ischial spine sign were measured bilaterally on anteroposterior radiographs; alpha angle (AA) was measured on lateral films, and anterior center-edge angle (ACEA) was measured on false-profile films. Independent t tests and Mann-Whitney U tests were used to compare mean angle measurements between dance and nondance athletes. Dichotomized categorical variables and crossover and ischial spine signs were analyzed between dance and nondance athletes by applying a chi-square test. Statistical significance was set as P < .05 a priori. Results: Significant differences in angle measurements were noted. AA was significantly lower in the dancers compared with the nondance athlete group (49.5° ± 6.0° vs 53.9° ± 7.3°, P = .001). The LCEA and ACEA of dance athletes were significantly greater compared with nondance athletes (33.8° ± 6.7° vs 30.9° ± 5.8° [P = .016] and 36.0° ± 8.1° vs 32.3° ± 7.0° [P = .035], respectively). No significant difference in AI was seen between the 2 cohorts (5.0° ± 4.0° for dancers vs 5.9° ± 3.4° for nondancers, P = .195). Conclusion: Significant differences existed in the radiographic bony morphology of young female single-sport dance athletes compared with nondance athletes with FAI. In dance athletes, symptoms were seen in the setting of normal bony morphology.