Performance analysis of the protective effects of bicycle helmets during impact and crush tests in pediatric skull models

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>Bicycle accidents are a very important cause of clinically important traumatic brain injury (TBI) in children. One factor that has been shown to mitigate the severity of lesions associated with TBI in such scenarios is the proper use of a helmet. The object of this study was to test and evaluate the protection afforded by a children's bicycle helmet to human cadaver skulls with a child's anthropometry in both “impact” and “crushing” situations.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>The authors tested human skulls with and without bicycle helmets in drop tests in a monorail-guided free-fall impact apparatus from heights of 6 to 48 in onto a flat steel anvil. Unhelmeted skulls were dropped at 6 in, with progressive height increases until failure (fracture). The maximum resultant acceleration rates experienced by helmeted and unhelmeted skulls on impact were recorded by an accelerometer attached to the skulls. In addition, compressive forces were applied to both helmeted and unhelmeted skulls in progressive amounts. The tolerance in each circumstance was recorded and compared between the two groups.</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Helmets conferred up to an 87% reduction in so-called mean maximum resultant acceleration over unhelmeted skulls. In compression testing, helmeted skulls were unable to be crushed in the compression fixture up to 470 pound-force (approximately 230 kgf), whereas both skull and helmet alone failed in testing.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Children's bicycle helmets provide measurable protection in terms of attenuating the acceleration experienced by a skull on the introduction of an impact force. Moreover, such helmets have the durability to mitigate the effects of a more rare but catastrophic direct compressive force. Therefore, the use of bicycle helmets is an important preventive tool to reduce the incidence of severe associated TBI in children as well as to minimize the morbidity of its neurological consequences.</jats:p></jats:sec>

Pediatric bicycle-related head injuries: a population-based study in a county without a helmet law

“…Several studies have reported the effectiveness of bicycle helmets in reducing the risk of head, brain, and severe brain injury by 63 to 88 % (Thompson et al 2000; American Academy of Pediatrics & Committee on Injury and Poison Prevention 2001; Mattei et al 2012; Yeung et al 2009) and facial trauma by 65 % (Thompson et al 2000). Our study supports the higher likelihood of brain injury among children not using bicycle helmets.…”

Impact of Helmet Use in Traumatic Brain Injuries Associated with Recreational Vehicles

“…Studies have shown that bicycle helmet use reduces the risk of brain injury by 88% [8]. A recent study that conducted crush tests using human cadaver skulls demonstrated that wearing a helmet can reduce the acceleration experienced by up to 87% during impact and also help the skull in resisting forces up to 47 pounds [9]. Population-based studies conducted to find out effectiveness of helmets in reducing severity of head injuries have reported results similar to those found in our study.…”

Towards clinical management of traumatic brain injury: a review of models and mechanisms from a biomechanical perspective

“…TBI can also result from static or near static loads that essentially crush the brain and skull, resulting in direct compression of the brain or contusion injury via bone fragments (Denny-Brown and Russell, 1940; López-Guerrero et al, 2012; Mattei et al, 2012). In these crushing or nutcracker injuries, the head is generally not subjected to the rapid linear or rotational movements that occur during impact injuries.…”