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Purpose: The purpose of this study was to introduce a new classification system for paediatric femoral neck fractures (PFNFs) and to evaluate its reliability. Methods: Two hundred and eight unilateral PFNFs (mean patient age: 9.0 ± 4.8 years) were included. Based on preoperative radiographs, the new classification system distinguished PFNFs without anterior or posterior translation (Type I), PFNFs with anterior (Type II) or posterior (Type III) translation, PFNFs with a comminuted medial or posterior column (Type IV), and subtrochanteric femoral fractures (SFFs; Type V). Radiographs were evaluated twice with an interval of two weeks by 19 raters with different specialties, experiences and geographical origins. The results were compared with a selection of 50 patient age-matched unilateral PFNFs and SFFs (mean patient age: 9.1 ± 4.9 years). These were graded twice by the same graders according to the Delbet-Colonna (D-C) classification. Results: Four radiologists and 15 paediatric orthopaedic surgeons from Europe and Asia graded the radiographs. Fair agreement was found between radiologists (κ = 0.296 ± 0.01) and surgeons (κ = 0.3 ± 0.005) (P = 0.17), although more experienced surgeons performed better than less experienced ones; a similar fair assessment was found for raters from Europe (κ = 0.309 ± 0.021) and Asia (κ = 0.3 ± 0.006) and for type II, III and IV fractures; the κ value in the first evaluation (0.309) was similar to that in the second evaluation (0.298). The overall κ value of the D-C classification subtypes was significantly higher (0.599 ± 0.217) than that of the new classification, 0.326 ± 0.162 (t = 3.190 P = 0.005). Conclusions: The new classification system showed fair reliability relative to the D-C classification. The reliability of the new classification system was not affected by the specialty or geographic origin of the rater or the evaluation round, only by rater experience level. The concordance was worse for PFNFs with anterior or posterior translation or with a comminuted medial or posterior columns. [ABSTRACT FROM AUTHOR]

Purpose: The simultaneous and ipsilateral occurrence of medial epicondylar and radial neck fractures is rare. This study evaluated the clinical and radiological outcomes of medial to lateral diagonal injury of the elbow (MELAINE). Methods: Six males and 6 females were diagnosed with MELAINE (left: 10, 83.3%; right: 2, 16.7%). Medial epicondylar and radial neck fractures were classified according to Papavasiliou's classification (seven type II, two type III, three type IV) and Judet's classification (three type I, four type II and five type III), respectively. All patients underwent surgery. The carrying angle, range of motion, and Kim et al. Elbow Performance Score were used to evaluate clinical and functional outcomes; related complications were recorded. Results: Mean age at injury and mean follow-up were 11.1 ± 2.5 (range, 6–14) and 40 ± 25.6 months (range, 13–90), respectively. All fractures consolidated in 6.3 ± 1.2 weeks on average (4–9). Outcomes were good (n = 1; 8.3%) to excellent (n = 11; 91.7%). The carrying angle of the injured and uninjured side was 15.5°± 2.6° and 14.7°± 2°, respectively (p = 0.218). The range of motion of elbow flexion-extension and forearm pronation-supination of the injured side was 144.2°± 10.4°, 4.6°± 5.4°, 76.7°± 9.1°, 80.4°± 9.2°, respectively, with no significant differences from the healthy side (p > 0.05). The Elbow Performance Score of the injured and uninjured side was 96.3 ± 5.3 and 98.8 ± 2.3, respectively (p = 0.139). No cases of infection, cubitus valgus, stiffness, or instability were recorded. Conclusion: Although uncommon, MELAINE should not be neglected. Surgery aims to stabilize the elbow and avoid valgus deformity. If diagnosed and treated, clinical and radiological results are excellent in most cases. [ABSTRACT FROM AUTHOR]

Abstract: Na0.6[Li0.2Mn0.8]O2 has been synthesized at different calcination temperatures by a solid state method. Its phase structure and electrochemical properties are investigated and discussed. Na0.6[Li0.2Mn0.8]O2 prepared at 600 °C shows a complicated structure and wonderful electrochemical performance. In the voltage range of 2.0 and 4.8 V, Na0.6[Li0.2Mn0.8]O2/Li cell delivers an initial discharge capacity of 247 mAh g−1 with an average voltage of 3.52 V, which demonstrates a very high energy density of 869 Wh kg−1. Furthermore, the material displays a stable capacity greater than 240 mAh g−1 over 30 cycles. [Copyright &y& Elsevier]

The major limitations of layered LiNi 0.5 Co 0.2 Mn 0.3 O 2 cathode materials are their severe capacity decay and marked impedance increase under a high cutoff voltage. Herein, a LiNi 0.5 Co 0.2 Mn 0.3 O 2 powder was successfully encapsulated by a compact and continuous La 2 O 3 thin layer via a facile freeze-drying method. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The excellent thermal stability and favorable lithium ion conductivity of the La 2 O 3 -modified sample lead to a substantial improvement in its electrochemical performances. In particular, the coated sample exhibits a capacity retention of 80% at 1 C over 150 cycles, while that of the bare electrode is only 58% at a high cutoff voltage of 4.6 V. The alternating current impedance and cyclic voltammetry tests reveal that the La 2 O 3 coating can reduce the cell polarization and enhance the electrochemical activity of cathode materials. [ABSTRACT FROM AUTHOR]

LiNi 0.8 Co 0.15 Al 0.05 O 2 crystals with ∼4 μm particle size have been synthesized from spherical Ni 0.8 Co 0.15 Al 0.05 (OH) 2 precursors via a two-step treatment strategy. A specific surface area controllable precipitation method was introduced to synthesize Ni 1-x-y Co x Al y (OH) 2 hydroxides with large specific surface area. Spherical hydroxides with large specific area and excess LiOH calcination technique ensure the LiNi 0.8 Co 0.15 Al 0.05 O 2 crystals with mono dispersed micrometer scaled particle distribution and perfect α-NaFeO 2 layered structure. Water washing process wipes off the LiOH and Li 2 CO 3 impurities from the cathodes efficiently without structural degradation. The LiNi 0.8 Co 0.15 Al 0.05 O 2 prepared via 15% excess lithium calcination presents an improved compacting density of 3.8 g cm −3 . The modified cathode material shows an initial discharge capacity of 174.5 mAh g −1 at 1C rate and 91.7% capacity retention after 100 cycles. The mono dispersed micron scaled morphology together with high structural stability endows the LNCAO material with superior compacting density and cycling capability for lithium ion batteries with high energy density. [ABSTRACT FROM AUTHOR]