Going Solo: Techniques for Emergency Fracture Management Without Assistance.

Orthopaedic injuries represent some of the most frequent conditions treated in emergency centers worldwide. Proper reduction techniques and evaluation of radiographic parameters are paramount in treating patients effectively. Orthopaedic providers at large tertiary centers may have several assistants available but are also burdened by notable patient loads and volumes. Frequently, fracture care may necessitate procedures performed by providers without the availability of skilled assistance, both in large tertiary academic centers and small independent emergency rooms with limited resources. As providers at a busy level 1 tertiary trauma center with only one primary orthopaedic resident responsible for the performance of most fracture reductions, we present both novel techniques and refined published approaches that allow the safe, efficient, and reliable reduction and stabilization of several different types of fracture dislocations with limited or no assistance, and only commonly found supplies.

An Unusual Terrible Triad Variant Associated with an Essex-Lopresti Injury.

Essex-Lopresti injuries and terrible triad injuries of the elbow are rare injuries that typically result from high-energy trauma such as falling from a height or a motor vehicle collision. However, the combination of an Essex-Lopresti injury and terrible triad injury is unique and poses a significant challenge for treatment as these injuries are independently associated with poor functional outcomes if they are not acutely diagnosed. We describe a case of a 19-year-old who presented with an unusual variant of a terrible triad injury associated with an Essex-Lopresti injury. The patient had a distal radioulnar joint (DRUJ) and elbow dislocation, a radial head and coronoid process fracture, and a distal radius fracture. Almost a reverse Essex-Lopresti, this injury was successfully managed with open reduction and repair of the distal radius, radial head, and damaged ligaments in the elbow, along with an internal joint stabilizer (IJS).

A metamaterial-enabled design enhancing decades-old short backfire antenna technology for space applications.

Nearly two decades of intense study have passed since the term metamaterials was first introduced in 1999. In spite of their great promise, however, metamaterials have been slow to find their way into practical devices, and examples of real-world applications remain rare. In this paper, an Advanced Short Backfire Antenna (A-SBFA), augmented with anisotropic metamaterial surfaces (metasurfaces), has been designed to achieve a very high aperture efficiency across two frequency bands. This performance is unprecedented for an antenna that has seen widespread use, but few design changes over its more than 50 year existence. The reduced weight, compact design, hexagonal aperture, high dual-band efficiency, high cross-polarization isolation, as well as low multipaction and passive intermodulation (PIM) risk make the A-SBFA ideal for spaceborne applications. This transformative design demonstrates how practical metamaterials, when applied to conventional antenna technology, can provide significant performance enhancements.

Standards for external fixation application: national survey under the auspices of the German Trauma Society.

INTRODUCTION: External fixation is widely accepted as a provisional or sometimes definitive treatment for long-bone fractures. Indications include but are not limited to damage control surgery in poly-traumatized patients as well as provisional bridging to definite treatment with soft tissue at risk. As little is known about surgeon's habits in applying this treatment strategy, we performed a national survey. METHODS: We utilized the member database of the German Trauma Society (DGU). The questionnaire encompassed 15 questions that addresses topics including participants' position, experience, workplace, and questions regarding specifics of external fixation application in different anatomical regions. Furthermore, we compared differences between trauma centre levels and surgeon-related factors. RESULTS: The participants predominantly worked in level 1 trauma centres (42.7%) and were employed as attendings (54.7%). There was widespread consensus for planning and intra-operative radiographical control of external fixation. Surgeons appointed at a level I trauma centre preferred significantly more often supra-acetabular pin placement in external fixation of the pelvis rather than the utilization of iliac pins (75.8%, p = 0.0001). Moreover, they were more likely to favor a mini-open approach to insert humeral pins (42.4%, p = 0.003). Overall, blunt dissection and mini-open approaches seemed equally popular (38.2 and 34.1%). Department chairmen indicated more often than their colleagues to follow written pin-care protocols for minimization of infection (16.7%, p = 0.003). CONCLUSION: Despite the fact that external fixation usage is widespread and well established among trauma surgeons in Germany, there are substantial differences in the method of application.

Dual-band planar electric metamaterial in the terahertz regime.

We present the design, fabrication, and measurement of a dual-band planar metamaterial with two distinct electric resonances at 1.0 and 1.2 THz, as a step towards the development of frequency agile or broadband THz materials and devices. A method of defining the effective thickness of the metamaterial layer is introduced to simplify the material design and characterization. Good agreement between the simulated and measured transmission is obtained for the fabricated sample by treating the sample as multi-layer system, i. e. the effective metamaterial layer plus the rest of the substrate, as well as properly modeling the loss of the substrate. The methods introduced in this paper can be extended to planar metamaterial structures operating in infrared and optical frequency ranges.

Experimental demonstration of electromagnetic tunneling through an epsilon-near-zero metamaterial at microwave frequencies.

Silveirinha and Engheta have recently proposed that electromagnetic waves can tunnel through a material with an electric permittivity (epsilon) near zero (ENZ). An ENZ material of arbitrary geometry can thus serve as a perfect coupler between incoming and outgoing waveguides with identical cross-sectional area, so long as one dimension of the ENZ is electrically small. In this Letter we present an experimental demonstration of microwave tunneling between two planar waveguides separated by a thin ENZ channel. The ENZ channel consists of a planar waveguide in which complementary split ring resonators are patterned on the lower surface. A tunneling passband is found in transmission measurements, while a two-dimensional spatial map of the electric field distribution reveals a uniform phase variation across the channel--both measurements in agreement with theory and numerical simulations.

Spin correlations and finite-size effects in the one-dimensional kondo box.

We analyze the Kondo effect of a magnetic impurity attached to an ultrasmall metallic wire using the density matrix renormalization group. The spatial spin correlation function and the impurity spectral density are computed for system sizes of up to L=511 sites, covering the crossover from Ll{K}, with l{K} the spin screening length. We establish a proportionality between the weight of the Kondo resonance and l{K} as a function of L. This suggests a spectroscopic way of detecting the Kondo cloud.