Functional outcome and complications in closed and grade I open tibia shaft fracture operated with intramedullary interlocking nail

Background: Treatment of open tibia fracture is controversial. Complications such as infection, re-operation, non-union and poor consolidation are also relatively common after these fractures. While grade II and III fractures are mostly treated with detriment and external fixator, grade I fractures are a matter of controversy. The purpose of this study is to evaluate factors affecting deep infections and fracture healing of closed and grade I open fracture of the tibial shaft treated with immediate or delayed interlocking IMN, and to study the functional outcome of the same.Methods: 60 Patients admitted to our institute with diagnosis of closed or grade 1 open tibia shaft fracture aged more than 18 years old between May 2016 to December 2016 were included. After initial evaluation and investigation, they were posted for surgery. Closed reduction and fixation with intramedullary nailing were done under spinal anesthesia. After discharge patients were followed up at an interval of 3 weeks, 3 months and 6 months and were evaluated using Johner and Wruhs criteria.Results: In our study, 91.67% patients have got excellent, 3.33% good and 1.67% poor results according to Johner and Wruhs criteria. Conclusions: Closed and grade one open fractures of the tibia shaft, managed with interlocking intramedullary nailing involves minimal surgical trauma and negligible blood loss while provides the advantages of early ambulation, lower rate of infection, delayed union, non-union and mal-union.

Effect of process parameters on mechanical properties of AA5052 joints using underwater friction stir welding

Underwater Friction Stir Welding (UFSW) is a solid-state joining technique which uses a non-consumable tool to weld metals. The objective of this investigation is to evaluate the mechanical properties of the AA5052 Aluminium alloy joints prepared by UFSW. The effect of different type of welding tools and welding parameters on the weld joint properties are studied. Square, tapered cylindrical and taper threaded cylindrical type of welding tools have been used to produce the joints with the tool rotational speed varying from 500 rpm to 2000 rpm while the welding speed varying from 50 mm/min to 150 mm/min. Tensile strength, micro-hardness distribution, fracture features, micro-and macrostructure of the fabricated weld joints have been evaluated. The effect of welding process parameters that influences the mechanical properties and fracture characterization of the joints are explained in detail. A maximum Ultimate Tensile Strength (UTS) value of 222.07 MPa is attained with a gauge elongation of 14.78%. Microstructural evaluation revealed that most of the fracture are found on the thermal mechanically affected zone (TMAZ)adjacent to the weld nugget zone (WNZ) due to bigger grain sizes. It is found that most of the joints exhibit ductile characteristics in failure. Fractography analysis has been used to find the behavior of weld joints in failure

Development of TSA anodized/MnVO sealed coating using a statistical approach for Al 7075 alloy and a study of its corrosion behaviour

In this work we propose a statistical approach which optimizes the operating parameters of tartaric sulfuric acid anodizing (TSA) and MnVO oxyanion sealing on Aluminium 7075 alloy. Here we used Response Surface Methodology and Taguchi Design to find an optimum condition for the surfaces with maximum corrosion resistance. This manuscript aims to provide a mathematical model which correlates coating thickness to anodizing parameters like voltage, temperature, sulfuric acid concentration, agitation, duration and tartaric acid concentration. Such combinatory approach has not been introduced or reported till now in optimizing the sealed anodic oxide layer to exhibit improved corrosion resistance. The surface of optimized TSA-MnVO sealed anodized coatings qualified 1000 h of salt spray exposure. The optical microscopic images clearly show the coating has excellent barrier and self-healing corrosion resistance behaviour in NaCl environment. The X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy of sealed anodized surface confirmed the presence of polymerized decavanadate species. The electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization test results revealed the resistance value of the coating is >15 MΩcm2 and corrosion current density (icorr) value of 4.5 nA/cm2 respectively, indicating excellent protective behaviour of the optimized coating in aggressive chloride environment

Performance Evaluation of Built Environment in Local Climate Zones

The thermal performance of a building is significantly influenced by the climate around it. It is observed that the microclimate of an urban area is notably different from that of the surrounding regions. This difference is mainly due to the variations in anthropogenic heat, built morphology and surface characteristics. The Local Climate Zone (LCZ) system, effectively classifies the urban areas concerning these climatic variations. This study comprises two sections; the first section explores the climatic differences across LCZs and the impact of urban built morphology on microclimate. For this, three different LCZs – LCZ-2, LCZ-5 and LCZ-9 (high, medium and low density respectively) were modelled within the range of values prescribed in the LCZ system and an analytical study was carried out with the help of the CFD tool – ENVIMET. To understand the influence of urban morphology features on microclimate, LCZ-2, a representative LCZ was chosen and a parametric study of variations in morphology variables was carried out. It was observed that incidence angle, surface characteristics and H/W greatly influence the microclimate. The second section of the study explores the thermal performance of the built environment across the LCZs. A typical 3-bedroom residential building was considered and thermal performance evaluation of the same in three different local climatic conditions was carried out through field measurements. It was observed that heat flux in LCZ-5 (65.5 W/m2) is high compared to that of LCZ-2 (16.6 W/m2) and LCZ-9 (6.04 W/m2). The study points to the significance of location-specific building performance studies and design criteria