Risk Factors of Musculoskeletal Injuries among the Marine Corps Enlisted Trainees / 대한산업의학회지

OBJECTIVE: The Korean Marine Corps enlistees endure tremendous physical and mental stress during basic military training, resulting in an increased risk of musculoskeletal injuries. The aim of this study was to investigate the incidence and type of the musculoskeletal injury problems and the risk factors associated with injuries among the Marine Corps recruits and to suggest preventive measures. METHODS: The study subjects were the Marine Corps recruits (n=8,231) who were enlisted from July, 2008 to March, 2009 for basic military training. We used a prospective cohort design and collected basic demographic information and subject musculoskeletal injury risk factors through a questionnaire on the first day basic training. The subjects were followed for the subsequent 6-week military training period. RESULTS: The cumulative incidence of musculoskeletal injuries was 13.4% during the 6-week training period, and more than half of the injuries involved the lower limbs at or below the level of the knee. Based on multivariate logistic regression analysis, the following factors were related to an elevated risk for injuries: age, height, educational level, subjective health perception, injury history during the past year, and stress scale after entrance. CONCLUSION: Based on our study results, the application of injury prevention measures such as stress management program and gradual fitness increasing program to the Marine Corps recruit training would contribute to the reduction of musculoskeletal injuries.

Left ventricular dysfunction measured by tissue Doppler imaging and strain rate imaging in hypertensive adolescents / 소아과

PURPOSE: Left ventricular (LV) hypertrophy and impaired diastolic function may occur early in systemic hypertension. Diastolic dysfunction is associated with increased cardiovascular risk. Tissue Doppler imaging (TDI)-derived tissue velocity and strain rate are new parameters for assessing diastolic dysfunction. The aim of this study is to determine whether TDI and strain rate imaging (SRI) would improve the ability to recognize early impaired diastolic and systolic functions compared with conventional echocardiography in hypertensive adolescents. METHODS: We included 38 hypertensive patients with systolic blood pressure above 140 mmHg or diastolic blood pressure above 90 mmHg. Ejection fraction and myocardial performance index (MPI) were estimated by conventional echocardiography. Peak systolic myocardial velocity, early diastolic myocardial velocity (Em), and peak late diastolic myocardial velocity (Am) were obtained by using TDI and SRI. RESULTS: In the hypertensive group, interventricular septal thickness was significantly increased on M-mode echocardiography. Em/Am was significantly decreased at the mitral valve annulus. Among hypertensive subjects, the E strain rate at basal, mid, and apex was significantly decreased. Systolic strain was significantly decreased at the septum in the hypertensive group. CONCLUSION: Strain rate might be a useful new parameter for the quantification of both regional and global LV functions and could be used in long-term follow up in hypertensive patients. Early identification by SRI of subjects at risk for hypertensive and ventricular dysfunction may help to stratify risk and guide therapy. Further studies, including serial assessment of LV structure and function in a larger number of adolescents with hypertension, is necessary.