Fracture Profile Research Articles

A Record-based Analysis of Profile, Pattern and Outcomes of Geriatric Fractures in a Tertiary CareHospital, Chandigarh

Introduction: Older people with diseased conditions are more prone to fracture irrespective of gender. Osteoporosis is the most common cause of elderly fractures. Objectives: 1) To ascertain the profile and pattern of geriatric fracture cases reporting a tertiary care institution, 2) To ascertain the extent of mortality and complications in geriatric fracture cases, and 3) To ascertain the functional outcomes of geriatric fracture cases discharged from the tertiary care institute. Methodology: A list of geriatric fracture inpatients of an institution was made for 2014 - 2018. The data on the profile of patients, type of fracture, treatment received, the lag time between the reporting and the surgery, comorbidities, past medical history, cause/ place of fracture, length of stay, and status at the time of the phone-based interview were analysed through SPSS software. Results: The highest range of the age for fracture occurrence was 60-70 years. Female patients were more than the male ones. Femur fracture was the most common. The most common direct cause of the fracture was fall (indoor). Open reduction, internal fixation and arthroplasty were the commonest treatment performed. The lag time between the patient arrival to the health care and surgery was 0-5 days. The highest length of stay by the patients in the hospital was 0-10 days. Conclusion: The possible direct causes of the fracture reported in the study were falls, roadside accidents, trauma etc.

Failure analysis of leakage at tube-to-tubesheet joints of a waste heat boiler

Failure analysis of a waste heat boiler with leakage occurring at the tube-to-tubesheet joint is presented in this study. In order to identify the causes of leakage, a series of investigations were conducted including visual inspection, chemical composition analysis, metallographic examination, hardness evaluation and crack fracture profile analysis. The results showed that the leakage was caused by the caustic stress corrosion cracking (caustic SCC), which was mainly resulted from the welding residual stress and caustic concentration between the tube and tubesheet. The welding flaw promoted the cracks initiation and growth, and widmanstatten structure in the heat-affected zone deteriorated the corrosion resistance. Furthermore, the mechanism of the caustic SCC was discussed. Finally, practical countermeasures were put forward to prevent the similar failure from happening again.

Microstructure evolution and mechanical properties of 308L stainless steel coatings fabricated by laser hot wire cladding

Laser hot wire cladding (LHWC) technology has been proved to be a very efficient laser cladding manufacturing process due to its advantages of fast deposition rate, high material utilization rate, and less environmental pollution. In this study, LHWC technology was used to prepare multiple layers of 308L stainless steel coatings on ordinary mild carbon steel substrates. The microstructure of the weldment section was evaluated by optical microscopy (OM). The results showed that the heat-affected zone (HAZ) of the sample was small, with a height of 1.58 mm and an area of 14.28 mm2. The metallurgical bonding between the substrate and coating was good. Because of the temperature gradient and grain growth rate, the grain morphologies in the different coating regions were different. From the bottom to the top, the grain morphologies were planar crystals, columnar dendrites, and equiaxed grains. Electron backscatter diffraction (EBSD) was used to obtain crystallographic information on the entire section of the sample. The interior of the cladding layer was mainly composed of columnar grains growing along the structural direction, most of which were coarse grains. The matrix and the HAZ consisted of fine equiaxed grains, and the crystal orientations were randomly distributed without obviously preferred orientations. Hardness analysis performed that the hardness of the HAZ was the highest, and the matrix had the lowest hardness. The hardness was higher in the layer-to-layer fusion zone and then gradually decreased with an increase in the cladding height inside each layer. The tensile test results illustrated that the elongation of the cladding layer (44.8 %) was higher than that of the HAZ (32.1 %) and the matrix (20.4 %) because the tensile direction of the tensile sample in the cladding layer was parallel to the laser scanning direction, which improved the tensile performance. The average grain size of the HAZ was the smallest, owing to the effect of fine grain strengthening, and the tensile strength was the highest(585 MPa). According to the tensile fracture profile, the sample matrix, HAZ, and the cladding layer exhibited ductile fractures.

Numerical Fracture mechanics based prediction for the roughening of brittle cracks in 2D disordered solids

The behavior of fractures in 2D brittle disordered materials results from the competition between the microstructural disorder that roughens cracks and the material elasticity that straightens them. The experimental fracture surfaces left behind are generally scale invariant and their complex geometry are still largely unexplained. Here, this issue is addressed numerically using the boundary element method that predicts incrementally the trajectory followed by cracks in an infinite elastic medium with a heterogeneous field of fracture energy. The predicted fracture profiles are characterized using their height-height correlation function and show scale invariant properties. In particular, simulated cracks are shown to follow a random walk with roughness exponent $$\zeta = 0.5$$ , irrespective of the level of microstructural disorder, indicating that the crack behavior is neither persistent nor anti-persistent, but instead, that the orientation of the next propagation increment is chosen randomly, independently of the past trajectory. This behavior is then interpreted from fracture mechanics calculations that show that the restoring force emerging from elasticity that generally straightens cracks vanishes in the limit of large specimens with respect to the characteristic size of the material heterogeneity. Our findings shed light on some experimental fracture patterns recently reported and suggests an explanation for the observation of two different types of fracture morphologies in 2D disordered brittle solids.

Surgical Management of Tibial Plateau Fractures with Locking Compression Plate


 INTRODUCTION
 Tibial plateau fracture is a common fracture that accounts for 1-2% of all fracture. Various treatment options including proximal tibial plating with locking compression plates are available for the treatment of tibial plateau fracture. This study was done to determine the clinical profile and functional outcome of tibial plateau fracture following locking compression plating.
 
 MATERIAL AND METHODS
 This prospective and observational study was carried out in Orthopedics Department of Universal College of Medical Sciences-Teaching Hospital (UCMS-TH) from December 2018 to July 2020. After Ethical clearance (UCMS/IRC/224/18) from Institutional Review Board (IRB) of UCMS-TH and informed written consent, all patients with tibial plateau fracture (Schatzker II-VI) who fulfilled the inclusion criteria were enrolled in the study and treated with locking compression plate. Post-operatively patients were regularly followed at 6 weeks, 3 months and 6 months for clinical, radiological and functional assessment. Descriptive statistics like frequency, percentage, mean and standard deviation were used to analyze the data.
 
 RESULTS
 In our study of 30 cases, the mean age was 37.77 ±15.65 years. Most of the cases were Schatzker type VI (13 patients) and type II (9 patients). The average duration for fractures union was 23.4 ±2.1 weeks. Superficial wound infection was the common complication seen in five cases. At six months, the mean knee society score (KSS) was 78 ±7.22 and majority of patients (19 patients) had good results.
 
 CONCLUSION
 Locking compression plate has an excellent functional and radiological outcome. It is an effective implant that can be adopted for the treatment of tibial plateau fractures in adults.

Impact of the COVID-19 Pandemic on Pelvic and Acetabular Trauma: Experiences From a National Tertiary Referral Centre.

IntroductionThe coronavirus disease 2019 (COVID-19) pandemic has had a significant impact on daily life. Restrictions imposed to help minimise virus transmission have limited both population movement and employment, as well as altering the potential mechanisms of high-energy trauma. The objective of this study was to assess the impact of the COVID-19 pandemic on pelvic and acetabular trauma.Materials and methodsA retrospective observational study of the incidence, causality, patient profile, fracture morphology, and treatment strategy of pelvic and acetabular trauma managed in a national tertiary referral specialist pelvic and acetabular centre between the 1st of March and 1st of August 2020 was undertaken and compared to corresponding time periods in the two preceding years.ResultsA total of 78 patients were referred for management following pelvic and acetabular trauma during the study period with a mean age of 52 years (SD +/- 24.2). Overall, 45% and 42% of patients were referred following isolated pelvic or acetabular fractures respectively. The most frequent mechanism of injury was a fall from height (>1m) (42%), with 53% of patients suffering from concomitant injuries and 32% requiring surgical management. While there was a statistically significant difference in mechanism of injury (P=0.026), there was no significant difference in overall incidence, fracture types, incidence of concomitant injuries, or overall proportion requiring surgical intervention during the study period when compared to previous years.ConclusionWhile some variation in the mechanisms of injury have been observed, the overall incidence, patient, fracture, and injury profiles associated with pelvic and acetabular trauma appear to have remained consistent during the COVID-19 pandemic. Additionally, the number and proportion of those requiring surgical treatment of these fractures have remained stable. Understanding the continued burden of these potentially severe injuries may help guide injury prevention, treatment, and resource allocation as the pandemic continues.

Profile of Fatal Head Injury Cases Autopsied at District Governament Hospital Mortuary

Background and Objectives: the study of profile of skull fractures is important as head being the most exposed and prominent part of body; it becomes most susceptible to injuries, as a result of criminal violence or accident. The present study was taken up to know the incidence of head injuries, age relationship,sex relationship, agent causing skull fractures, common skull bone fractures. Methodology: data in the current study was collected from the autopsy reports and from police inquest of all fatal skull fractures from the period of june 2012 to may 2014 irrespective of age and sex with history of death due to head injuries brought for postmortem examination to the department of forensic medicine & toxicology, al-ameen medical college mortuary and district hospital mortuary, bijapur between june 2012 to may 2014.Results: most common circumstance causing skull fractures are road traffic accidents in 77 cases (81.94 %). Male preponderance over females noted in this study with males constituting 80 cases (85.10 %) and females 14 cases (14.89 %). The most common age group affected was 21-30 years. Blunt force is the most common agent causing the skull fracture in 90 cases (95.74 %) and least is sharp in 4 cases (4.25 %). Among skull fracture comminuted fracture were seen in 46 cases (48.93%) , linear fracture in 38 cases (40.42%), depressed fracture in 8cases (8.5%) and sutural fracture in 1 case and gutter fracture in 1 case (1.06%) respectively. Temporal bone was the commonest bone fracture in 17 cases (18.08%). Conclusion: the study had concluded that incidence of skull fractures were common at the age group of 21-30 years, with male predominance, most common cases were those of RTA, cause of death that were given in majority of cases was that of Head injury as a consequence of injuries sustained.

Fracture Height Growth Prediction Using Fluid Velocity Based Apparent Fracture Toughness Model

This paper outlines the development of a fracture height growth prediction model that uses the modified rock mechanical properties obtained from a combination of fluid flow and rock material property behavior and applies them during the calibration process to match actual treatment data resulting fracture height growth evolution and profile. The traditional fracture growth models are closely linked with the fracture toughness parameter which is not only difficult to estimate but is also considered dynamic in nature as it may assume various geometry-dependent values rather than a fixed input value. To account for this limitation, this study uses the fluid tip velocity to estimate apparent fracture toughness during the initial model setup process and continuously scales the model during the fracture growth prediction phase. The influence of controllable parameters such as injection rate and fluid viscosity on vertical growth of fractures was studied and applied to field examples. Analysis from the modeling work on two of the case histories presented, indicated a rapid fracture growth in the first few minutes of the treatment that was proportional to the rate of net pressure gain. The influence of the fracture tip on the fracture pressures in the tip region is visible only in the early part of the treatment and are relatively short-lived especially once the contribution from viscous flow pressures dominates the pressure behavior. The findings are presented in detail and are helpful from a treatment planning and execution viewpoint as they provide a detailed insight into fracture propagation. Relevant theory, equations and workflow adopted during the study are presented for ready adaptation in the field.

Anisotropy of Microstructure and Tensile Properties of Additive Manufactured ZTC4 Alloy

ZTC4 alloy prepared by electron beam melting was hot isostatically pressed, the macro-and microstructure were characterized by stereo microscopy and optical microscopy, the tensile properties were tested and the fracture profiles were characterized using scanning electron microscopy. The results show that: The vertical deposition samples exhibit coarsen epitaxial columnar grains and the parallel samples show equiaxed grains, and microstructure are basket-weave α+β phase. The vertical deposition samples exhibit very high ultimate tensile strength and yield strength but poor ductility with elongation and shrinkage, and show generally more planar and faceted fracture morphology. The anisotropy in tensile properties is mainly due to the difference in the orientation of the columnar grains with respect to the tensile test direction, and the characteristics of the minor fracture plane are mainly related to the α colonies.

A Novel Procedure for Coupled Simulation of Thermal and Fluid Flow Models for Rough-Walled Rock Fractures

An enhanced geothermal system (EGS) proposed on the basis of hot dry rock mining technology has become a focus of geothermal research. A novel procedure for coupled simulation of thermal and fluid flow models (NPCTF) is derived to model heat flow and thermal energy absorption characteristics in rough-walled rock fractures. The perturbation method is used to calculate the pressure and flow rate in connected wedge-shaped cells at pore-scale, and an approximate analytical solution of temperature distribution in wedge-shaped cells is obtained, which assumes an identical temperature between the fluid and fracture wall. The proposed method is verified in Barton and Choubey (1985) fracture profiles. The maximum deviation of temperature distribution between the proposed method and heat flow simulation is 13.2% and flow transmissivity is 1.2%, which indicates the results from the proposed method are in close agreement with those obtained from simulations. By applying the proposed NPCTF to real rock fractures obtained by a 3D stereotopometric scanning system, its performance was tested against heat flow simulations from a COMSOL code. The mean discrepancy between them is 1.51% for all cases of fracture profiles, meaning that the new model can be applicable for fractures with different fracture roughness. Performance analysis shows small fracture aperture increases the deviation of NPCTF, but this decreases for a large aperture fracture. The accuracy of the NPCTF is not sensitive to the size of the mesh.

Experimental study on surface morphology and relevant plugging behavior within acid-etched and unetched fractures

Plugging and diverting acid fracturing is an indispensable and promising technology that aims to enhance productivity for complex carbonate reservoirs. The key to success for this technology is the formation of effective plugged zones within preexisting fractures. However, because fracture pattern before and after acid-etching is quite different, the plugging behavior of fibers and particulates within acid-etched fractures is correspondingly distinct with respect to within smooth and hydraulic fractures. Till now, a number of researches have been studied on plugging experiments with various apparatuses. However, the plugging laws within acid-etched fracture are still unclear, and the experimental results are insufficient in revealing specific plugging laws, particularly with respect to fracture morphology. In this paper, we propose new parameters to analyze fracture morphology and introduce an integrated experimental method as well to study plugging behavior within fractures with different morphologies. Firstly, we obtain acid-etched fracture profiles with a 3D scanner and reproduce the rough physical-model fracture using 3D printing technology. Then, we perform a series of experiments to grasp plugging laws. Finally, in terms of fracture features analysis and experimental results, we further analyze the correlation between plugging behavior and surface morphology. The calculation results of digital parameters show that after acid-etching the roughness of the whole fracture increases due to acid-rock interaction, and channels are formed along the flow direction. Meanwhile experimental results show that flat fractures are relatively difficult to be plugged with respect to rough fractures because it has corresponding lower abilities to capture fibers and particulates. Pure fibers can independently plug 2 mm-wide fractures, as fracture width increased, the addition of particulates will improve the plugging efficiency. Additionally, fracture surface morphology has a huge influence on plugging behavior and dominate the possibility of plugging formation. Plugged zones generally are formed in the roughest areas of the fracture.

Numerical Investigation on the Influence of Surface Flow Direction on the Heat Transfer Characteristics in a Granite Single Fracture

As fluid passes through the fracture of an enhanced geothermal system, the flow direction exhibits distinct angular relationships with the geometric profile of the rough fracture. This will inevitably affect the heat transfer characteristics in the fracture. Therefore, we established a hydro-thermal coupling model to study the influence of the fluid flow direction on the heat transfer characteristics of granite single fractures and the accuracy of the numerical model was verified by experiments. Results demonstrate a strong correlation between the distribution of the local heat transfer coefficient and the fracture morphology. A change in the flow direction is likely to alter the transfer coefficient value and does not affect the distribution characteristics along the flow path. Increasing injection flow rate has an enhanced effect. Although the heat transfer capacity in the fractured increases with the flow rate, a sharp decline in the heat extraction rate and the total heat transfer coefficient is also observed. Furthermore, the model with the smooth fracture surface in the flow direction exhibits a higher heat transfer capacity compared to that of the fracture model with varying roughness. This is attributed to the presence of fluid deflection and dominant channels.

Palate Fracture Profile in Plastic Reconstructive and Aesthetic Surgery of Soetomo Hospital : January 2012 – December 2017

Background: Palatal fractures are often associated with maxillofacial fractures and Le Fort fractures. The diagnosis and management of palatal fractures in the midface area is a challenge for a plastic surgeon in restoring function and aesthetics. With the results of this study, it is expected to be a database of maxillofacial fractures treated at SMF Reconstructive Plastic Surgery and Aesthetic Dr. Soetomo, Surabaya and gave the ability to make a fast and precise diagnosis for time and technical maxillofacial fractures.Methods : This study uses medical record data for all patients diagnosed with palatal fractures in Dr. Soetomo General Hospital, Surabaya during January 2012 to December 2017. The variables studied were demographic data including sex, age, mechanism of occurrence of accidents, types of fractures, management, complications that occur and length of treatment.Results : There were 82 patients with palatal fractures, with traffic accidents being the most common cause of palate fracture (n = 61) followed by workplace accidents and households in second place (12 and 9%). Most sufferers were men (68%), women (14%) with the highest age range of men aged 19-30 years who were followed by ages 31-45. The most were parasagittal fractures (56%), then Sagittal (15%), paraalveolar (9%), alveolar (1%), comminutive (1%). no fractures with anterior and posterolateral alveolar types, posterolateral type or transverse type fractures. Hospitalization period with plating (12 days), transmolar wiring (10.6 days), conservative (13.8 days).Conclusions: In this study assessed the experience in the reconstruction and aesthetic plastic surgery department of Dr. Soetomo General Hospital regarding palatal fractures and accompanying demographic data. The type of fracture that occurs is also related to the management performed. Incomplete medical records caused problems in this study.

Discrepancy between Forward and Reverse Seepage Characteristics in a Single Rough Fracture

Under the uniform seepage boundary condition, the forward and reverse seepage flow rates will vary widely. In response to this phenomenon, this paper studies the mechanism of the difference in seepage characteristics between the forward and reverse directions from the fracture profile’s roughness, Darcy and non‐Darcy seepage, and distribution of eddy currents. First of all, wavelet transform was used to decompose and reconstruct the single rough fracture for 8 times, and then 9 fracture models with various roughness degrees were constructed. Then, Finite Volume Method was used to simulate the seepage in the original and approximate models of the Reynolds number varying from 0.001 to 1000. The results show that the nonlinear seepage is necessary for the difference between the forward and reverse seepage characteristics of the single rough fracture. The mechanism of the discrepancy between forward and reverse nonlinear seepages is the diverse shapes and distribution of the eddy current generated by the forward and reverse seepage. The secondary roughness provides space for the existence and development of the eddy current. The secondary roughness is the geometric basis of the discrepancy between the forward and reverse seepage characteristics.

Outcomes of plate-screw fixation of humeral shaft fractures in three hospitals of the city of Yaoundé

Background: Surgical management of humeral fractures involves several methods including plate-screw fixation, intramedullary nailing, external fixation, and pinning. Nowadays, the most used surgical method is plate-screw fixation. Objective: The aim of this study was to present the short-, medium- and long-terms outcomes of plate-screw fixation of humeral fractures in three hospitals in the city of Yaoundé. Material and Methods: This was a descriptive and retrospective study with prospective evaluation carried out in the orthopedic and trauma surgery departments of three hospitals in the city of Yaoundé, over a period of 6 years and 4 months. We analyzed the medical records of the operated patients and did a physical reevaluation of the patients using a pre-conceived tested data sheet. The following variables were studied: socio-demographic characteristics, fracture profile, clinical and radiological profile, and the functional prognosis of the shoulder and elbow joints (using the Constant and Murley score, and the Mayo elbow performance score respectively). Data analysis was done using the software Statistical Package for Social Sciences (SPSS) version 23.0. Results: Eighty-two cases of osteosynthesis were recorded. The mean age of the patients was 37.9 ± 11.5 [16 – 71] years and there was a male predominance (sex ratio of 2.7). The dominant humerus was most involved (96.4%). Closed fractures were predominant (65.8%), and the majority (47%) of them were simple fractures. The diaphysis was the most affected bone part (69.5%). Road traffic accidents accounted for 70.7% of the fractures. Two patients had a polytrauma, 26 had multiple fractures, and 54 had an isolated humeral fracture. The mean operating time (for the osteosynthesis) was 122 min and the mean blood loss volume during surgery was 296 cc. There was a significant correlation between these two variables. Postoperative complications included 8 cases of postoperative radial palsies (who recovered within an average of 4 months), 06 cases of superficial skin infections, 05 cases of secondary displacements, 03 cases of implant damage and 02 cases of vicious callus. The bone reductions were sub-anatomical in 79% and cortical fixation was good in 72.6% of cases. Consolidation was achieved within an average of 18 weeks. The consolidation time significantly varied according to the type of fracture line and the type of reduction obtained. Functional recovery of the shoulder and elbow was nearly normal in all patients. The mean Constant and Murley score was 96.9 while the mean Mayo elbow performance score of 97.3. Conclusions: Plate-screw fixation enables an adequate management of humeral fractures with acceptable clinical and radiological results, low complication rates, and good functional outcomes.

Orbital Floor Fractures: Epidemiological, Clinical and Therapeutical Study at Sylvanus Olympio University Teaching Hospital in Lomé about 51 Cases

Introduction: Orbital floor fractures are a significant pathology among maxillofacial injuries. They can cause oculomotor, sensory, and sometimes esthetic disorders. The goal of this study was to determine the epidemiological profile of orbital floor fractures and show their clinical and therapeutic approach in Lomé. Patients and method: This was a descriptive retrospective study of orbital floor fractures collected in the ENT and maxillofacial surgery department of Sylvanus Olympio University Hospital in Lomé over 8 years (January 1, 2011 to December 31, 2018). Results: We reviewed 63 cases of orbital floor fractures out of 552 cases of facial trauma. According to the inclusion and non-inclusion criteria, we retained 51 cases. The hospital frequency of orbital floor fractures was 9.24% of facial fractures. The average age of the patients was 35 ± 10.34 years. Males were predominant (ratio = 7.5). The main etiology was road accidents (92.16%). Ophthalmological signs were dominated by vertical diplopia (31.37%), limited eye movement (25.49%), and enophthalmia (29.41%). The sensory sign was dominated by suborbital hypoesthesia (13.73%). Surgical treatment was performed in 86.27% of patients. The average intervention time was 17.84 ± 12.69 days after the trauma. The main approach was the subciliary route (65.91%). The surgical procedures consisted of muscle and fat removal (20.45%) and orbital floor repair by mesh plate (50%). The average length of hospitalization was 9.63 ± 5.23 days. Surgical site infection was the main postoperative complication observed in 3.92% of patients. The main sequelae were diplopia (4.55%), suborbital hypoesthesia (4.55%), and enophthalmos (4.55%). Conclusion: Orbital floor fractures are mainly due to road accidents. Management must be multidisciplinary and adequate in order to avoid irreversible functional and/or morphological sequelae. Their prevention consists of effective combat of road accidents.

Perfil epidemiológico das diferentes fraturas de fêmur de pacientes internados em um hospital do norte de Minas Gerais

Objetivo: Analisar o perfil epidemiológico, sociodemográfico e clínico das fraturas de quadril e femoral de pacientes internados em um Hospital do Norte de Minas Gerais. Métodos: Trata-se de um estudo epidemiológico, com delineamento documental, retrospectivo, descritivo e analítico conduzido com 144 pacientes que deram entrada no hospital com fratura de Fêmur e Quadril entre o período de janeiro de 2018 a janeiro de 2020. Para obtenção dos dados, foi utilizado um formulário sociodemográfico (idade e sexo) e prontuário para a evolução (retrospectiva). Os dados foram analisados através da estatística descritiva utilizando-se o programa IBM SPSS Statistics. O projeto foi aprovado pelo Comitê de Ética em Pesquisa. Resultados: Na amostra de 144 pacientes, 97 (67,4%) apresentava idade maior que 60 anos, não havendo distinção entre os sexos. O mecanismo de trauma mais frequente foi “queda da própria altura”, apresentado por 94 (65,3%) pacientes. O tipo de fratura mais comum foi a de fêmur proximal, com 95 (66%) casos. Conclusão: Observou-se que as fraturas de terço proximal, ocorreram em pacientes idosos, com predominância do sexo masculino nas fraturas do colo e do sexo feminino nas fraturas trocantéricas.

FracRough—Computer program to calculate fracture roughness from reservoir rock core

Measuring roughness of fractures in buried rock is challenging, but important in estimating fracture shear strength and permeability. Here, we present FracRough, a first-of-its-kind computer program that was developed to calculate the joint roughness coefficient (JRC) of reservoir rock fractures from core exterior. Core is often acquired from oil and gas wells using particular drilling bits that cut rocks in a cylindrical shape. The reservoir fractures that are intersected by core typically have planar shapes, and can be profiled and digitized from 360° photographs of the core exterior. The digital profiles appear on the unrolled 360° core photographs as sinusoids, reflecting the elliptical intersections of fracture planes with cylindrical core. Wavelength of the sinusoid is equal to the circumference of the core and amplitude is related to the angle between the core and the fracture. A planar fracture has a profile of perfect sinusoid. However, the actual fractures have a rugged, rough, irregular top and bottom traces (profiles). The purpose is to calculate the degree of roughness denoted as JRC. The way to accomplish this is to fit a sinusoid to the irregular fracture profile. JRC is calculated using the distance of the obtained fracture profiles from a fitting sinusoid at original measurement points. For each fracture, JRC is calculated for top and base profiles separately. FracRough also calculates correlation coefficient and standard deviation of aperture between top and base profiles as mismatch parameters. Mismatches in fracture walls indicate slippage along fracture and/or diagenetic cementation and dissolution.

Gram negative chronic osteomyelitis

Background: To assess the demographic profile, clinical and microbiological characteristics, management and treatment outcome in chronic osteomyelitis caused by gram negative organisms. Methods and materials: A chart review of inpatients admitted with chronic osteomyelitis due to gram negative organisms was done over one year from August 2017 to August 2018 in a tertiary care centre in Mumbai. Following data was recorded: demographic profile, clinical presentation, type and site of fracture, intraoperative cultures, management and clinical outcomes. Results: The study cohort comprised of 23 patients [14(61%) males]. Mean age was 54 years (range, 21–83 years). Most common site of fracture was tibia [n = 8 (34%)]. Most common clinical presentation was discharging sinus/wound [n = 20(86%)]. The mean duration of symptoms was 6 months (range, 6weeks–2years). A total of 25 gram negative organisms were isolated from 23 intraoperative samples. 12/25(48%) of these organisms were multi-drug resistant [4/12(33%) were carbapenem resistant and 8/12(66%) were extended spectrum beta-lactamase resistant]. 3/23 (13%) patients had simultaneous Staphylococcus aureus infection. 20/23 (86%) underwent combined surgical and medical management, [9/20(45%) surgical debridement (no implants), 6/20(30%) implant removal and debridement, 3/20(15%) implant retention and debridement, 2/20(10%) underwent amputation]. 3/23(14%) were treated with only antibiotics. Antibiotic impregnated beads were inserted in 8/23 patients. 18/23 (78%) patients had good clinical outcome and 5/23(22%) required repeated debridement (2 had implant retention, 2 had carbapenem resistant organism). Conclusion: Gram negative orthopaedic infections with resistant organisms are especially difficult to manage due to limited antibiotic options, poor penetration at the site of infection, need for prolonged duration of treatment and repeated surgical interventions. Synergistic combination of susceptible antibiotics with extensive debridement and antibiotic impregnated cement/beads at the local site may yield good results.

Fracture behavior of pre-cracked polyethylene gas pipe under foundation settlement by extended finite element method

Polyethylene (PE) pipes are often used for transporting gas and water, which play an important role in lifeline engineering. Such pipes, especially with notches, scratches or cracks, can be subject to actions inflicted by nature or man-made factors. To ensure that the pipes can continue to operate, even after being subjected to foundation settlement, it is necessary to study the fracture behavior of the pipes. In this work, a model was developed based on extended finite element method (XFEM) to study the fracture behavior of pre-cracked PE pipe under foundation settlement. Key parameters' effects on ultimate bearing capacity, including initial crack sizes, internal pressures and transition section length, were determined. Tensile results demonstrate that the stress-strain relationship of the pre-cracked PE pipe specimen involves two-stage, i.e., the elastic stage and the failure stage. There was obvious crack propagation in the macro fracture profile when the tensile test was performed on pre-cracked PE specimens. Simulation results demonstrate that the initial crack depth exerts a more significant influence on the ultimate bearing capacity for the pipe than the initial crack length. The internal pressure will enhance the bending resistance of the pipe, which inhibits crack propagation. In addition, the length of the transition section exerts a significant influence on crack propagation.