Object All-terrain vehicle (ATV) usage has grown tremendously over the years, reaching 9.5 million vehicles in use in 2007. Accompanying this growth has been a concomitant increase in rider morbidity (including traumatic brain and spine injuries) and death, especially in children. The purpose of this study was to define and measure, through field testing, those physical attributes intrinsic to riders, such as height, weight, and wingspan, which may have implications for ATV riders' safety. Methods Three field tests (J-hook, brake, and bump) were developed and performed to allow direct measurement of the lateral, longitudinal, and vertical dynamics in 5 riders of varying heights, weights, and wingspans. Two ATVs, a utility and a sport model, were tested for further comparisons. Data were acquired using a comprehensive data acquisition system attached to the ATVs. Assignment of individual rider/ATV test safety ratings and a rider/ATV Total Safety Rating were made from the results of these field tests. Results The J-hook test results demonstrated that larger rider wingspans positively influence ATV rider safety and mitigate against lateral instability. From the brake test it was determined that a 10-in (25.4-cm) longitudinal displacement, such as that experienced during a sharp deceleration, for a rider of any height or weight, breached the level of defined safety. As rider weight increased, displacement decreased. The bump test provided evidence that increased rider weight also mitigates against vertical displacement. Conclusions Individuals with light weights and small wingspans, such as those in the pediatric population, are under considerable risk of injury when operating an ATV due to lateral, longitudinal, and vertical operational instability.

Object 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. Methods 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. Results 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. Conclusions 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.

Object Intracranial arachnoid cysts are a relatively common benign intracranial pathology, accounting for as many as 0.75%–1% of nontraumatic CNS lesions. Although it has already been demonstrated that rupture of arachnoid cysts may lead to subdural hematomas/hygromas, no study to date has investigated benign extracerebral collection in infancy as a possible predisposing factor for further development of arachnoid cysts. Methods The authors performed a retrospective imaging and chart review of macrocephalic infants 12 months old or younger who were referred to neurosurgical care at OSF St. Francis Medical Center from 2003 to 2010, and who were diagnosed with benign extracerebral fluid collection in infancy on thin-slice (1-mm) head CT scans. Special attention was given to the investigation of risk factors for further development of de novo arachnoid cysts. Several epidemiological factors in the infants and mothers were analyzed, including gestational age at delivery, mode of delivery, mother's age at delivery, delivery complications, birth weight, age of macrocephaly development, degree of macrocephaly, family history of macrocephaly, prenatal and postnatal history of infection, fontanel status, presence of papilledema, previous history of head trauma, and smoking status. Imaging characteristics of the initial scans, such as location of subdural collection (frontal vs frontoparietal and frontotemporal) and presence of ventriculomegaly, were also evaluated. For those patients in whom arachnoid cysts were identified on subsequent CT scans, the size and location of the cysts were also analyzed. Results The authors identified 44 children with benign extracerebral fluid collection in infancy. From this group, over a mean follow-up of 13 months (range 6–13 months), 18 children developed intracranial arachnoid cysts (a 40.9% incidence of de novo development of arachnoid cysts), with 27.8% presenting with bilateral cysts. In the multiple logistic regression analysis, infants who presented with an extracerebral collection restricted to the bilateral frontal region were more likely to develop intracranial arachnoid cysts (p = 0.035) than those with collections involving the frontotemporal and frontoparietal regions (odds ratio [OR] = 5.73). Additionally, children with benign extracerebral fluid collections and plagiocephaly were more likely to develop intracranial arachnoid cysts (p = 0.043) than those without plagiocephaly (OR = 4.96). Conclusions This is the first report in the neurosurgical literature demonstrating that benign extracerebral fluid collections in infancy may constitute a significant risk factor for development of de novo arachnoid cysts. These findings support a 2-hit hypothesis for the development of arachnoid cysts, in which the combination of an embryological defect in arachnoid development followed by a second event leading to impairment of CSF fluid absorption in early childhood could lead to abnormal CSF dynamics and the consequent expansion of fluid collections in the intraarachnoid spaces.

Temporary shunting of infants with pseudo-meningocele constitutes a viable therapeutic alternative with favorable clinical outcomes and a low risk of shunt dependency similar to those of children with SDH.

Ecchordosis physaliphora (EP) is a rare non-malignant mass that originates from remains of the notochord and is typically asymptomatic. A 42-year-old man presented with sudden onset of painless horizontal diplopia and his neurological exam showed sixth cranial nerve palsy. Magnetic resonance imaging (MRI) identified a non-enhanced retroclival mass (EP) with increased signal intensity on T2 and decreased signal intensity on T1-weighted sequences. He was treated with methylprednisolone, completely recovered in four weeks and has remained symptom free. Conservative management should be attempted before surgery in all cases since symptoms can resolve spontaneously and EP could be an incidental finding.