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Author(s): Y. Tsujimoto [1]; C. Tassel [1, 2]; N. Hayashi [3]; T. Watanabe [1]; H. Kageyama (corresponding author) [1]; K. Yoshimura [1]; M. Takano [4, 5]; M. Ceretti [2]; C. [...]

Posterior shoulder dislocation is a rare event that may occur after a direct trauma, an epileptic seizure, electric shock or electroconvulsive therapy. In more than 50% of the cases, posterior dislocations are missed on initial evaluation and often misdiagnosed as frozen shoulders with unfortunate consequences. We present the case of a missed posterior subluxation and reverse Hill Sachs lesion (McLaughlin lesion) in a 40-year-old woman caused by anelectric shock of 240 V. The patient underwent surgery in our institute two weeks after the injury. The humeral head was reduced and the reverse Hill Sachs lesion was filled by demineralized bone matrix allograft with osteoinductive factors. Tendons were repaired and a temporaneous artrodesis was performed. At the final follow up of 12 months, we obtained a Costant Score of 93 and the patient returned to her previous daily activities. [ABSTRACT FROM AUTHOR]

Abstract: An investigation of the quaternary Ln2O3–SrO–NiO–CuO system has shown that compounds of the formula Ln2−x Sr x Ni0.8Cu0.2O4−δ (0< x <2) with Ln=La, Nd and Gd adopt the K2NiF4-type structure, but a new phase of stoichiometric composition is formed only at x =1.67 (LnSr5Ni2.4Cu0.6O11) with the smaller lanthanides cations Dy, Ho and Er. All the samples have been prepared at 1150°C in 1atm of O2 gas flow using conventional solid state methods. Rietveld refinement of their crystal structures from powder X-ray diffraction data confirms that they adopt the tetragonal structure (space group I4/mmm, Z =2). Magnetic susceptibility data for Ln2−x Sr x Ni0.8Cu0.2O4−δ (0< x <2) with Ln=La, Nd, Gd, Dy, Ho and Er between 2 and 350K show Curie–Weiss behavior at higher temperatures characteristic of Ln3+ cation. [Copyright &y& Elsevier]

Results are presented from neutron diffraction measurement of the strains in each phase, matrix and reinforcement, of a metal matrix composite bar before and after deformation beyond the elastic limit by four-point bending. The strains in each phase have been converted to stress. A stress separation technique was then applied, and the contributing mechanisms separated and identified. In this way the changes in the different contributions owing to plastic deformation have been determined. It is found that, initially, the average phase stresses can be explained in terms of a combination of essentially hydrostatic phase average thermal misfit stresses in the matrix (tension) and particles (compression) combined with a parabolic macrostress from quenching. After plastic bending the change in axial macrostress is as expected for that for a monolithic bar, but unexpectedly the misfit stresses had relaxed to approximately zero in both the tensile and compressive plastically strained regions of the bar. [Copyright &y& Elsevier]

Non-stoichiometric 214-nickelates with Ruddlesden-Popper (RP) type frameworks emerged as potential candidates for mixed electronic/ionic conductors in the intermediate temperature range. In this work we investigated structural aspects of the oxygen ion mobility diffusion mechanisms in non-stoichiometric Nd 2 NiO 4+ δ nickelates by X-ray (laboratory and synchrotron) as well by neutron diffraction. Temperature dependent synchrotron powder diffraction revealed a phase diagram of unprecedented complexity, involving a series of highly organized, 3D modulated phases related to oxygen ordering below 800 K. All phase transitionsimply translational periodicities exceeding 100 Å, and are found to be of 1 st order, together with fast ordering kinetics. These surprising structural correlations, induced by the presence of interstitial oxygen atoms, suggest a collective phason-like oxygen diffusion mechanism together with dynamical contributions from the aperiodical lattice creating shallow diffusion pathways down to room temperature., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The support material can play an important role in oxidation catalysis, notably for CO oxidation. Here, we study two materials of the Brownmillerite family, CaFeO 2.5 and SrFeO 2.5 , as one example of a stoichiometric phase (CaFeO 2.5, CFO) and one existing in different modifications (SrFeO 2.75 , SrFeO 2.875 and SrFeO 3 , SFO). The two materials are synthesized using two synthesis methods, one bottom-up approach via a complexation route and one top-down method (electric arc fusion), allowing to study the impact of the specific surface area on the oxygen mobility and catalytic performance. CO oxidation on 18 O-exchanged materials shows that oxygen from SFO participates in the reaction as soon as the reaction starts, while for CFO, this onset takes place 185 °C after reaction onset. This indicates that the structure of the support material has an impact on the catalytic performance. We report here on significant differences in the catalytic activity linked to long-term stability of CFO and SFO, which is an important parameter not only for possible applications, but equally to better understand the mechanism of the catalytic activity itself.

Modular neck hip prosthesis born in the 1990 with the aim of allowing the surgeon to modify CCD angle, offset and femoral anteversion intra-operatively restoring patient's original biomechanics. In order to achieve the best biomechanics of the reconstructed hip, preoperative planning is essential. In the last few years modularity has been questioned and an argument made for the return to mono block stems due to events of breakage or disconnection of modular components. Fretting or crevice corrosion may lead to failure of such modular device due to the contamination inside the modular coupling or to high loads. We present a case of repetitive modular femoral neck prosthesis fracture.

Purpose: Bone stock reconstruction in TKR surgery is one of the biggest challenges for the surgeon. According to some, authors causes of bone stock loosening are multiple, including stress shielding, osteolysis from wear, septic or aseptic loosening, and bone loss caused by a poorly balanced implant. Moreover, bone loss may be iatrogenic at the time of implant removal, indicating that bone preservation during implant removal is critical., Methods: Defect localization and extension affect the surgeon's decisions about the choice of the surgical technique and the type of plant to be taken. Today there are several options available for bone deficiency treatment. The treatment choice is undoubtedly linked to the cause of revision, experience and personal philosophy, but it is necessary to consider also the patient's age, expectations of life, functional requirements and bone quality. Many authors prefer bone stock reconstruction techniques in patients with high bone quality and a better quality of life with more prospects. In patients with lower lease on life and lower bone quality the best bone replacement techniques are of modular systems, wedges, and augments. In cases with septic bone loss, more or less extended, different authors recommend reducing bone grafts in favor of modular prostheses to reduce the risk of graft contamination., Results: All of these techniques have been shown to be durable in midterm outcomes, but concerns exist for a number of reasons, including disease transmission, resorption, fracture, immune reaction to allograft, the cost of custom prostheses, the inability to modify the construct intraoperatively and the overall technical challenge of applying these techniques., Conclusions: The choice between different surgical options depends on bone defect dimension and characteristics but are also patient-related. Reestablishment of well-aligned and stable implants is necessary for successful reconstruction, but this can't be accomplished without a sufficient restoration of an eventual bone loss.

In this report we analyse a case of ischiatic tuberosity avulsion. A 15-year-old patient who came to our first aid department two days after a football match accident was treated conservatively and examined at month 1-4, 6 and 12. In order to examine patient condition, a new index was formulated: the inability score index (ISI), which is based on hip range of motion and scales for rest, walking, running pain and compared to other parameters such as oedema area, fragment diastasis evaluated by X-ray and CT accordingly. ISI defines the inability as severe, moderate and mild. It guides the rehabilitative program in the right way. In this case, the patient was able to run softly after 35 days and to go back to the full agonist activity after 4 months. At the end of treatment the patient referred to the complete pain remission, full range of motion recovery and a good fracture consolidation. After 1 year we discuss about therapeutic strategies used and results obtained.