Modification of hurling helmets causing penetrating upper limb injury: A case series demonstrating opportunity for improved player safety.

BACKGROUND: The games of hurling and camogie involve fast ball movement and a substantial physical contact with opposing players. The wearing of protective helmets with faceguards became obligatory 10 years ago and resulted in a significant reduction of craniofacial injuries. However since then a trend has emerged of players modifying helmets to improve comfort and vision. As officials are not yet required to perform pre-match checks, many players enter competition with defective protective equipment which poses a risk to both themselves and others. METHODS: We present 4 cases of penetrating upper limb injury in hurlers sustained as a result of helmet faceguards. These injuries were sustained during competitive play and the affected patients presented with portions of the faceguards embedded in their wounds. Each patient required admission to hospital and exploration of their wounds under general anaesthetic. CONCLUSIONS: This case series demonstrates the dangers of modification and damage to protective helmet faceguards used in hurling and camogie. We encourage helmet manufacturers to re-engage with players to ensure that current safety equipment meets the functional demands of the modern player while adhering to approved manufacturing standards. Mandatory helmet checks before competitive games would reduce the likelihood of penetrating upper limb injury to players.

A Case of Dorsal Scapular Neuropathy in a Young Amateur Boxer.

Neuropathies of the muscles surrounding the shoulder joint are a well-documented cause of pain and weakness in sports people. Repetitive or excessive traction on the nerve supplying the affected muscle is believed to be the primary mechanism. We describe a case of this phenomenon in a young amateur boxer which has never been described in the literature previously. We document our hypothesis on the mechanism of injury as well as a successful treatment strategy we employed. This paper is designed to highlight shoulder pain with associated winging of the scapula should make one wary of a dorsal scapular neuropathy particularly in a sports person who utilises repetitive forceful actions.

Extensive Deep Venous Thrombosis Resulting from Anterior Lumbar Spine Surgery in a Patient with Iliac Vein Compression Syndrome: A Case Report and Literature Review.

Study Design Case report. Objective Although May-Thurner syndrome or iliac vein compression syndrome is covered in the vascular literature, it remains absent from the orthopedic and neurosurgery literature and has not been previously reported to occur in concordance with spine surgery. We review the salient points of disease presentation, diagnosis, and treatment. Methods A 33-year-old woman was followed postoperatively via clinical and radiographic findings. Her presentation, operative treatment, postoperative extensive deep venous thrombosis (DVT) formation, and management are described. Results We present a unique case of a healthy 33-year-old woman who developed an extensive left iliac vein DVT after anterior lumbar spine fusion. Although she had multiple risk factors for thrombosis, the size of the thrombus was atypical. A subsequent venogram showed compression of the left common iliac vein by the right common iliac artery, consistent with May-Thurner syndrome. Conclusions May-Thurner syndrome or iliac vein compression syndrome is a rare diagnosis that is absent from the spine literature. The condition can predispose patients to extensive iliac vein DVT. The contributing anatomy and subsequent clot often require catheter-directed thrombolysis and stenting to achieve a favorable outcome.

Synthesis, excited state dynamics, and optical characteristics of oligophenyl-based swivel cruciforms in solution and solid state.

Oligophenyl-based swivel cruciforms are an amorphous class of materials for potential use in display applications. In this work, we describe the design, synthesis, and structural and optical properties of a group of chromophores with varying degrees of π-conjugation that produce blue emission and high photoluminescence quantum yields (PLQYs). The swivel cruciforms are branched complexes consisting of two arms, and the relative rotation of these arms is an important factor that determines the optical properties of these systems. The studies reveal that the physical size of the system, that is, the arms, and the presence and position of functional groups results in different degrees of sterical effects. This has a dramatic impact on the interplay between nonradiative and radiative decay of the excited state. For the least π-extended system, control of the excited state decay can be achieved by modifying the properties of the medium through an increase in the viscosity, which is demonstrated accordingly. The data shows that an intramolecular excited state is responsible for the swivel cruciform emission in solution. The character of this "aggregate" and its emission is not dissimilar to an excimer, and we therefore attribute it to an intramolecular excimer. In the solid state, a combination of intra- and intermolecular excimers are the most likely source of the emission. The data also shows that intra molecular excimers can produce a surprisingly high PLQY, when either properties of the medium facilitate this or when functional groups introduce steric hindrance, which subsequently prevents the nonraditive decay through conformational change.

On the angular dependence of the optical polarization anisotropy in ladder-type polymers.

Two ladder-type polymers have been examined using polarized optical absorption and fluorescence spectroscopy in solution and solid state. The fluorescence anisotropy excitation spectra of ladder-type methyl-substituted poly(para-phenylene) and poly(naphthylene-phenylene) follow their absorption profiles, contrary to the typical behavior in other conjugated polymers, which show excitation wavelength dependent anisotropy until the onset of the typical red edge effect. Using Raman microscopy and linear dichroism of aligned stretched polyethylene films containing the ladder polymer, it has been found that the orientation of the absorption transition dipole moment is dependent on the conjugation length. The transition dipole of the shorter conjugation lengths of the distribution is localized approximately 7 degrees off axis, and that of the longer conjugation lengths is delocalized along the chain.

The relationship between cholinesterase inhibition and two types of swimming performance in chlorpyrifos-exposed coho salmon (Oncorhynchus kisutch).

Brain acetylcholinesterase (AChE) activity was evaluated after two different swimming tests in coho salmon (Oncorhynchus kisutch; 238 +/- 5 g) given 96-h exposures to 0, 5, 10, 20, or 40 microg/L of chlorpyrifos. Brain AChE activity decreased in a concentration-dependent manner (AChE activities were 81.8, 52.2, 37.3, and 21.3% of control for the 5, 10, 20, and 40 microg/L exposures, respectively), whereas swimming performance was impaired after a threshold of AChE impairment was reached. Specifically, for swimming performance (U(crit)) measured using the established ramp-U(crit) test (duration, 152 +/- 8 min), this threshold occurred with AChE activity of 68.5% +/- 18.1% of control. For a rapid acceleration test (U(deltav), where V represents velocity; 27.6 +/- 0.8 min), this value was 52.6% +/- 15.4% of control. Both swim protocols resulted in similar maximum swim speeds (control ramp-U(crit) and U(deltav) values of 3.44 +/- 0.09 and 3.71 +/- 0.13 body lengths/s, respectively), and performance was significantly reduced after 20 and 40 microg/L exposures in both groups (ramp-U(crit) values: 86.4 and 83.6 %, respectively, of control; U(deltav) values: 85.2 and 77.8%, rsepectively, of control). Although both tests yielded similar swim speeds, postexercise plasma lactate concentrations were greater for the U(deltav) test (11.3 +/- 0.6 vs 8.6 +/- 0.5 mmol/L), indicating a greater anaerobic effort. This increase was exaggerated after 10 microg/L of chlorpyrifos (14.6 +/- 1.3 mmol/L), indicating that anaerobic muscle was used to attain the same speed. Given the threshold relationship between AChE inhibition and swimming performance, coho salmon appear able to maintain integrated swimming activity despite significant impairment of an underlying neurological control mechanism.

Solution processable organic field-effect transistors utilizing an alpha,alpha'-dihexylpentathiophene-based swivel cruciform.

A pentathiophene-based swivel cruciform, which allows rotation between the cruciform arms, was synthesized. Homogeneous microcrystalline films were processed from solution, and field-effect transistors utilizing this dimer gave hole mobilities up to 0.012 cm2/V.s.

Synthesis and spectroscopy of an oligophenyl based cruciform with remarkable pi-pi assisted folding.

A facile route has been developed for the preparation of a new family of oligophenyls based on a 2,5,2',5'-tetra-aryl substituted biphenyl structural motif. The cruciform terphenyl dimer 2,5,2',5'-tetra(4-tert-butylphenyl)-1,1'-biphenyl () has been prepared in a two step protocol as a representative of this interesting class of materials. The thermal behaviour of the cruciform was analysed by DSC and shows that forms an amorphous glass when cooled from the isotropic melt. Subsequent heating reveals a glass transition temperature at 130 degrees C. X-Ray single crystal structure analysis of 2,2'-bis(4-tert-butylphenyl)-1,1'-biphenyl () and shows that both these molecules with a quater-phenyl substructure adopt a folded solid-state structure. Examining the (1)H NMR spectra of and reveals that the interactions that induce this folding in the solid-state are sufficiently strong to bias foldamer formation also in solution. Consequently, it is reasonable to assume that the folded conformation within the lattice is due to intramolecular pi-pi interaction rather than being imposed by crystal packing. The optical properties of the cruciform terphenyl dimer are discussed relative to the linear analogue 1,4-bis(4-tert-butylterphenyl)benzene ().

Semiconducting polyfluorenes with electrophosphorescent on-chain platinum-salen chromophores.

The synthesis of statistical fluorene-type copolymers with on-chain Pt-salen phosphorescent units and their use in electrophosphorescent OLEDs is reported.