Characterization of all-terrain vehicle-related thoracolumbar spine injury patterns in children using the AOSpine classification system.

PURPOSE: To evaluate thoracolumbar spine injury patterns, demographics, and clinical characteristics in pediatric patients following all-terrain vehicle-related trauma. METHODS: A retrospective review of patients 0-17 years old admitted to a level I trauma center following an ATV-related incident from 2004 to 2013 was performed. Thoracolumbar spine injury patterns, accident mechanism, driver/passenger status, and demographic and clinical data were compared between patients with and without a spine injury. RESULTS: Of 456 pediatric patients involved in ATV-related trauma, 36 sustained one or more thoracolumbar spine injuries (7.9%). These patients tended to be older, taller, heavier, and had a higher BMI. ATV rollover was the major statistically significant mechanism of injury to cause spine fractures (61%). Patients with spine injuries had twice the hospital length of stay compared with those without (4 days vs. 2 days, P = 0.003). Nonstructural spine injuries (A0) were the most common type of injury (49.1%), followed by wedge-compression fractures (A1) (41.1%). In patients with a thoracolumbar spine injury, there was a mean of 3.11 spine injuries per child. Four (10%) patients with thoracolumbar spine fractures also sustained a cervical spine fracture. CONCLUSION: Once a thoracolumbar spine injury has been detected in a patient, the entire spinal column should be scrutinized because there is a high likelihood for additional injuries throughout the spine. Younger pediatric patients (≤ 8 years old) exhibit a spine fracture pattern distinct from that of older children who have a mature osseous-ligamentous complex.

Understanding the effects of dielectric medium, substrate, and depth on electric fields and SERS of quasi-3D plasmonic nanostructures.

The local electric field distribution and the effect of surface-enhanced Raman spectroscopy (SERS) were investigated on the quasi-3D (Q3D) plasmonic nanostructures formed by gold nanohole and nanodisc array layers physically separated by a dielectric medium. The local electric fields at the top gold nanoholes and bottom gold nanodiscs as a function of the dielectric medium, substrate, and depth of Q3D plasmonic nanostructures upon the irradiation of a 785 nm laser were calculated using the three-dimensional finite-difference time-domain (3D-FDTD) method. The intensity of the maximum local electric fields was shown to oscillate with the depth and the stronger local electric fields occurring at the top or bottom gold layer strongly depend on the dielectric medium, substrate, and depth of the nanostructure. This phenomenon was determined to be related to the Fabry-Pérot interference effect and the interaction of localized surface plasmons (LSPs). The enhancement factors (EFs) of SERS obtained from the 3D-FDTD simulations were compared to those calculated from the SERS experiments conducted on the Q3D plasmonic nanostructures fabricated on silicon and ITO coated glass substrates with different depths. The same trend was obtained from both methods. The capabilities of tuning not only the intensity but also the location of the maximum local electric fields by varying the depth, dielectric medium, and substrate make Q3D plasmonic nanostructures well suited for highly sensitive and reproducible SERS detection and analysis.