A comparison of sub-concussive impact attenuating capabilities of ice hockey helmets with and without XRD foam.

OBJECTIVES: To compare the impact attenuating capabilities between ice hockey helmets manufactured with and without XRD impact protection foam, worn with and without a XRD skullcap, at reducing sub-concussive head accelerations. DESIGN: Quasi-experimental laboratory. METHODS: Ice hockey helmets were fit onto a Hybrid III 50th Head Form Head and dropped 25 times onto the left temporal side for each condition: XRD foam helmet, XRD foam helmet with XRD skullcap adjunct, non-XRD foam helmet, and non-XRD foam helmet with XRD skullcap adjunct. The helmets were dropped from a height that resulted in sub-concussive linear accelerations (25-80 g's). Using a tri-axial accelerometer, peak linear accelerations (g) were measured, and the average was used to compare impact attenuation properties across the four conditions. RESULTS: The highest linear accelerations were observed in the XRD foam helmet without skullcap (32.97 ±â€¯0.61 g) and were significantly greater (p < 0.001) than the XRD helmet with skullcap (21.38 ±â€¯0.76 g). The helmet without XRD foam elicited the lowest peak linear accelerations (16.10 ±â€¯0.73 g) which were significantly lower than the XRD foam helmet regardless of whether the skullcap was added (p < 0.001). CONCLUSIONS: Although sub-concussive loads are potentially just as dangerous, much of the research regarding helmet and skullcap efficacy appears to be at high concussive impacts; <70 g's. The findings suggest that helmets with incorporated XRD foam, either within the design or added as an adjunct, are less effective at attenuating linear accelerations at sub-concussive levels than the low-density foam helmet.

Radius of Care in Secondary Schools in the Midwest: Are Automated External Defibrillators Sufficiently Accessible to Enable Optimal Patient Care?

CONTEXT: Sudden cardiac arrest is the leading cause of death among young athletes. According to the American Heart Association, an automated external defibrillator (AED) should be available within a 1- to 1.5-minute brisk walk from the patient for the highest chance of survival. Secondary school personnel have reported a lack of understanding about the proper number and placement of AEDs for optimal patient care. OBJECTIVE: To determine whether fixed AEDs were located within a 1- to 1.5-minute timeframe from any location on secondary school property (ie, radius of care). DESIGN: Cross-sectional study. SETTING: Public and private secondary schools in northwest Ohio and southeast Michigan. PATIENTS OR OTHER PARTICIPANTS: Thirty schools (24 public, 6 private) volunteered. MAIN OUTCOME MEASURE(S): Global positioning system coordinates were used to survey the entire school properties and determine AED locations. From each AED location, the radius of care was calculated for 3 retrieval speeds: walking, jogging, and driving a utility vehicle. Data were analyzed to expose any property area that fell outside the radius of care. RESULTS: Public schools (37.1% ± 11.0%) possessed more property outside the radius of care than did private schools (23.8% ± 8.0%; F1,28 = 8.35, P = .01). After accounting for retrieval speed, we still observed differences between school types when personnel would need to walk or jog to retrieve an AED ( F1.48,41.35 = 4.99, P = .02). The percentages of school property outside the radius of care for public and private schools were 72.6% and 56.3%, respectively, when walking and 34.4% and 12.2%, respectively, when jogging. Only 4.2% of the public and none of the private schools had property outside the radius of care when driving a utility vehicle. CONCLUSION: Schools should strategically place AEDs to decrease the percentage of property area outside the radius of care. In some cases, placement in a centralized location that is publicly accessible may be more important than the overall number of AEDs on site.