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Objectives To characterize the fracture pattern and pattern of fragmentation for displaced, midshaft clavicle fractures undergoing operative management. Design Prospective observational study. Setting Two institutions. Level 1 and Level 2 Trauma Centers. Patients/participants Fifty-three patients who underwent operative repair of midshaft clavicle fracture. Intervention All clavicles were treated by operative open reduction internal fixation. Main outcome measurements All clavicles were categorized by the Robinson classification based on injury plain film bilateral upright clavicle radiographs. In addition, intraoperative fracture characteristics of fragment length and location were measured and recorded to evaluate the fracture pattern. All fractures were analyzed to determine the frequency of segmental comminution versus length-stable patterns, analyze characteristics of butterfly fragment size, number and location as well as the location of the cortical read for those length-stable fractures. Results Analysis revealed 55% were Robinson 2B2 based on preoperative radiographs. Length-stable, anatomic reduction was achievable in 83%. For those in which an anatomic cortical read was achievable, 97.7% had a read present in the posterior-superior aspect of the clavicle. Conclusions Midshaft clavicle fractures that meet conventional criteria for operative repair occur in a predictable manner with butterfly fragments generated from anterior-inferior compression and simple fracture line generated from tension along the posterior-superior aspect of the clavicle. Understanding this pattern can assist in the in surgical planning.

This article describes main radiologic signs of bony structures that form acetabulum. The methods of poly projection x-rays study and evaluation of it are described. Also, authors show rational algorithm of choosing fracture type according to JudetLetournel classification. Case presentation is based on simple fracture types.

Computed tomography (CT) scans with 3-dimensional (3D) reconstruction are the gold standard of imaging for complex fractures. However, visualising CT imaging can be challenging. With increasing access to 3D printing, we postulate that life-sized 3D models can better assist in visualising CT images, aiding preoperative planning of tibial plafond fractures. 3D models of 3 tibial plafond fractures of differing complexities were printed. We approached surgeons in our institution who manage tibial plafond fractures to complete a questionnaire on preoperative planning of the cases based on CT scans. We then examined whether analysing the 3D models after that changed the plan. This included ratings on the usefulness, accuracy, and ease of use of the models. Six surgeons participated in the study. In the simple fracture model, median usefulness was graded as 4.5 (range minimum to maximum: 0 to 7), accuracy 8 (4 to 10), and ease of use 9 (7 to 10) with 0 being the lowest and 10 being the upper limit of how useful, accurate, or easy to use the models were. For the intermediate fracture, median usefulness was 6.5 (2 to 8), accuracy 7.5 (3 to 10), and ease of use 8.5 (7 to 10). For the complex fracture, median usefulness was 6 (1 to 9), accuracy 7.5 (1 to 9), and ease of use 8.5 (0 to 9). We attribute these poorer scores to difficulty in processing the scans, resulting in less accurate printing of the many fragments in complex impacted fractures. In conclusion, 3D-printed models are easy to use and accurate in preoperative planning of tibial plafond fractures. Most surgeons believe that 3D models and CT scans combined were more useful than CT scans alone.

Mode I crack propagation in prestressed concrete sleepers B70 is simulated by a fracture mechanics approach. The plastic damage model, which takes the non-linear behavior of concrete into account, is utilized to calculate crack length and crack mouth opening displacement (CMOD). Numerical data from prestressed concrete sleepers B70 under three-point bending load are compared with those of the proposed fracture mechanics model. In this study, fracture mechanics parameters of prestressed concrete sleepers are investigated. Sleepers with the length of initiation crack of 5 to 45 mm (with 10 mm steps) and the width of initiation crack of 2 to 8 mm (with 2 mm steps) are analyzed. Sleeper cracks are created in the notch and both of its sides. These analyses confirm that the structural behavior of prestressed concrete sleepers can be predicted by a simple fracture mechanics model provided that the related material properties like KIC, crack length and CMOD, are known.

Femoral shaft fractures refer to the fracture of the femur from 5 cm under the lesser trochanter to 2 cm above the femoral condyle. According to the 2007 AO/OTA classification, it can be divided into 3 types: type A simple fracture, type B wedge fracture, and type C comminuted fracture.

Fractures are major flow paths for solute transport in fractured rocks. Conducting numerical simulations of reactive transport in fractured rocks is a challenging task because of complex fracture connections and the associated nonuniform flows and chemical reactions. The study presents a computational workflow that can approximately simulate flow and reactive transport in complex fractured media. The workflow involves a series of computational processes. Specifically, the workflow employs a simple particle tracking (PT) algorithm to track flow paths in complex 3D discrete fracture networks (DFNs). The PHREEQC chemical reaction model is then used to simulate the reactive transport along particle traces. The study illustrates the developed workflow with three numerical examples, including a case with a simple fracture connection and two cases with a complex fracture network system. Results show that the integration processes in the workflow successfully model the tetrachloroethylene (PCE) and trichloroethylene (TCE) degradation and transport along particle traces in complex DFNs. The statistics of concentration along particle traces enables the estimations of uncertainty induced by the fracture structures in DFNs. The types of source contaminants can lead to slight variations of particle traces and influence the long term reactive transport. The concentration uncertainty can propagate from parent to daughter compounds and accumulate along with the transport processes.

Preoperative skin sterilization, disinfection, and fracture reduction are all necessary for surgeries of the fractured lower extremity. This procedure requires several medical personnel, even though its tasks are relatively simple. Therefore, development of an assistant device for the preoperative disinfection and the simple fracture reduction is required as an alternative. To obtain the design specifications of the equipment, we evaluated lifting and traction forces using the lower extremities of Korean fresh cadavers. The lifting force was measured when each leg was lifted from the table using 39 Korean fresh cadavers. The same method was applied to measure the traction force on a femoral fracture model using 22 Korean fresh cadavers. The mean lifting force was 36.8 ± 11.8 N, and the mean traction force was 116.8 ± 37.9 N. Regression analysis yielded the following equations: lifting force = 0.6724*(body weight) - 0.8068, R2 = 0.71; traction force = 1.6880*(body weight) + 18.1495, R2 = 0.57. This study determined the lifting and traction forces, not just the body segment weights. These results will be helpful for developing medical assistant devices.

Summary Introduction Injuries to the tarsometatarsal (Lisfranc) joint cover a broad range from subtle, ligamentous injuries to complex fracture-dislocations with severe soft tissue trauma. Almost all existing classifications for injuries at the tarsometatarsal joint either describe the direction of displacement or are based on the trauma mechanism as recollected by the patient. In the current study the literature is reviewed to obtain insight in the existing classifications regarding tarsometatarsal joint injuries (Lisfranc injuries). A new classification is presented based on biomechanics and injury severity. Material and method The electronic databases up to May 1st 2018 of ‘Pubmed Medline’, ‘EMbase’, and ‘Google Scholar’ were searched. Expert consensus was reached on a new classification proposal. Results Based on the literature on biomechanics at the tarsometatarsal level, the foot is divided into a medial (M), central (C) and lateral (L) column. A simple classification is proposed based on the severity of the damage to the tarsometatarsal joint per column. The different grades of injury are: 0, not involved; 1, pure ligamentous injury; 2, simple fracture; 3, comminuted fracture. Conclusion The proposed classification allows for classification of all types of injury ranging from subtle to frank fracture-dislocations. The next step will have to be to validate the classification using inter- and intra-observer agreement.

An 8-month-old girl presented with a right raccoon eye and right Battle’s sign ([figure 1A,B][1]), which are signs of a basal skull fracture,[1][2] after a fall from a height of 40 cm the previous day. A head thin-slice CT scan revealed a right parietal bone simple fracture ([figure 1C,D][1])

Stable fractures of the ankle can be safely treated non-operatively. It is also gradually being recognised that the integrity of the ‘medial column’ is essential for the stability of the fracture. It is generally thought that bi- and tri-malleolar fractures are unstable, as are pronation external rotation injuries resulting in an isolated high fibular fracture (Weber type-C), where the deltoid ligament is damaged or the medial malleolus fractured. However, how best to identify unstable, isolated, trans-syndesmotic Weber type-B supination external rotation (SER) fractures of the lateral malleolus remains controversial. We provide a rationale as to how to classify SER distal fibular fractures using weight-bearing radiographs, and how this can help guide the management of these common injuries. Cite this article: Bone Joint J 2017;99-B:851–5.

Unconventional resource exploration has boosted U.S. oil and gas production, which is successfully by horizontal well drilling and hydraulic fracturing. The horizontal well with multiple transverse fractures has proven to be effective stimulation approach could increase reservoir contact significantly. Unlike the single fracture planes in typical low permeability sands, fractures in shales tends to generate more complex, branching networks. The concept of stimulated reservoir volume (SRV) was developed to quantitative measure of multistage fracture interact with natural fractures in unconventional reservoir. However, the simple fracture modeling of the past do not suitable for the complex scenarios simulation. This paper reviews the mainstream characterization method of stimulated reservoir volume in shale reservoirs, including microseismic interpretation, rate transient analysis method, analytical and semi-analytical method and numerical method. Finally, the systematic evaluation of application conditions with respect to each method and further research directions for characterization method are proposed.

Because of the anterior disposition on the face and the fragility of the anatomy, the mandible is commonly affected in facial fractures, and the angle region represents 32% of the mandibular fractures; therefore, the objective of the paper was to present a proposal for late correction of the mandibular fracture already consolidated and with occlusal alteration. Patient J.C.P.R., 32, during anamnesis reported loss of sensibility in the mentalis region as well as unilateral posterior open bite for having been a victim of an automobile accident about 1 year and 3 months ago. Physical examination showed elevation in the right mandibular angle region due to the poor positioning of fractured stumps. It has been found that the patient suffered a simple fracture at the mandibular angle, but that had not been treated previously, and it was necessary to treat the fracture sequel. Refraction was performed with a new reduction and fixation through titanium plates and screws, showing that, even being late, the procedure to reduce the fracture sequela was effective, even with the correct functional occlusal adjustment.

In this paper, we propose a model for the description of bone mechanics and bone remodeling processes, including bone cell populations dynamics. The latter, described by a system of ODEs, influences the values for the elastic parameters used in the mechanical model, which in turn determines the “stimulus” function affecting the behavior of the cells. Numerical simulations concerning the behavior of the bone under external loads, as well as simple fracture healing processes are presented. The model can reproduce the qualitative behavior of bone tissue remodeling and mechanical response.

This study aimed to determine if 3D printing can affect surgeon’s selection of plate for distal tibia fracture surgery and to find out whether orthopedic surgeons consider this technology necessary and would use it in their practice. A total of 102 orthopedic surgeons were asked to choose anatomically contoured locking plates among 5 most commonly used types for one simple and one complex distal tibia fracture based on X-ray and CT images. Next, they were provided real-size 3D printed models of the same fractures, allowed to apply each of the 5 plates to these models, and asked if they would change their choice of plate. A 10-point numeric rating scale was provided to measure the extent of the help that 3D printing provided on preoperative planning. Finally, we asked the surgeons if they would use 3D printing in their practice. Seventy-four percent of inexperienced surgeons changed their selection of plate after using 3D printed models for the complex fracture. In contrast, only 9% of experienced surgeons changed their selection of plate for the simple fracture. Surgeons rated the extent of usefulness of the 3D models in preoperative planning as a mean of 4.84 ± 2.54 points for the simple fracture and 6.63 ± 2.54 points for the complex fracture. The difference was significant (p < 0.001). Eighty-six percent of inexperienced surgeons wanted to use 3D models for complex fractures. However, only 18% of experienced surgeons wanted to use 3D printed models for simple fractures. The use of a real-size 3D-printed model often changed surgeon’s preoperative selection of locking plates, especially when inexperienced surgeons evaluated a complex fracture. However, experienced surgeons did not find 3D models very useful when assessing simple fractures. Future applications of 3D models should focus on training beginners in fracture surgery, especially when complex fractures are concerned.

Notched three-point-bending (3 PB) tests of small concrete samples with a fixed depth/size but various span/depth ratios can be performed in almost every laboratory. Additional usefulness is added to the flexibility of those fixed-depth 3 PB tests in this study by providing a simple closed-form solution for determination of the depth and span independent tensile strength ft and fracture toughness KIC measurable from 3 PB samples with any span-depth ratio. Material constants, ft and KIC, only existed asymptotically for large concrete structures are determined by the simple fracture mechanics model regardless the span-depth ratio. Recent results of notched 3 PB tests with 6 span-depth ratios (2, 2.5, 3, 4, 5 and 6) were analysed again by the closed-form model and compared with the effective fracture toughness in the previous study (without ft). A good agreement in KIC values was obtained. That is the two different fracture models have affirmed the usefulness of small notched 3 PB tests of a fixed depth/size but with flexible choices of the span/depth ratio. Moreover, the weight of specimens is suggested to be considered when the span/depth ratio is greater than 4.0 for 3 PB tests. Finally, fracture statistics analysis, not considered by the previous method, was included in this study, which provided the 95% reliability band besides the mean ft and KIC values.

For historical riveted steel railway bridges fatigue assessment and calculation of the remaining fatigue life based on SN-curves is a big challenge, due to missing traffic data of the past and often unsatisfactory conservative results (no remaining fatigue life, but no fatigue cracks detected). As an alternative, a fracture mechanics approach based on the assumption of an initial crack length and an analysis of the stable crack growth behaviour seems helpful. Within a research project, four dismounted girders of the carriageway of an old steel lattice girder bridge (year of construction: 1908, end of service life: 2018) were used for specific fatigue tests in the laboratory. Starting from artificial notches, initial cracks at the critical positions at the rivet holes of riveted girders were induced and the development of the crack fronts was measured, simulating rivets with and without clamping force. First, the scope and execution of these fatigue tests are presented in the paper, completed by a comprehensive evaluation of the development of the crack fronts. Then a simple fracture mechanics model is presented and calibrated based on the test data. With this model the remaining fatigue life of riveted girders, with high fatigue pre-damage, can be determined for the borderline cases either without or with high clamping forces in the rivets.

Maximum loads of notched three-point-bend specimens with constant height are used to determine the tensile strength and fracture toughness of concrete. Normally the tensile strength and fracture toughness cannot be obtained from small three-point-bend specimens because of the highly heterogeneous composite structures of concrete and formation of fictitious crack prior to the maximum load. A simple fracture model is established, linking fictitious crack to the maximum aggregate size so that the concrete structure and fictitious crack formation can be considered together. Maximum loads of three-point-bend specimens with different initial notches containing different influence of the tensile strength and fracture toughness are then analyzied.

Horizontal drilling and hydraulic fracturing produce Unconventional Liquid Reservoirs (ULRs) economically. One of the characteristics of the ULRs is high production declining rate, and thus enhanced oil recovery techniques such as Huff-n-Puff will ensue. In addition, the existence of complex fracture network has been proven by both field and simulation work. This study investigated the potential of CO 2 huff-n-puff in ULRs with complex fracture networks. Two fracture characterization techniques for complex fracture network such as fractal-based, and microseismic-based were applied to reduce uncertainties of fracture networks and thus improve the accuracy of simulation input. In order to study complex CO 2 recovery mechanism, lab-measured data was upscaled to the field-scale, and then used for evaluating production performance of a simple fracture network. Detailed sensitivity analysis showed that diffusion in the field scale is negligible compared with other recovery mechanisms such as oil swelling, gas expansion, viscosity reduction, etc. The following comparison between dual continuum and the explicit fracture modeling approaches highlights the importance of heterogeneity due to the explicit fractures. Dual continuum models yields less accurate pressure behavior than explicit discrete fracture models even though production behavior could be history matched.

This paper deals with the effect of mixed mode I/III loading on fracture resistance of hot mix asphalt (HMA) mixtures at a low temperature of −15 °C. In order to simulate mixed mode I/III loading, a new simple fracture test configuration using semi-circular bend (SCB) specimen containing a tilted crack was proposed by performing many finite element analyses. The SCB specimens were produced utilizing gyratory compaction machine. A simple three-point bend fixture was employed for loading the test specimens. Critical stress intensity factors were then calculated using fracture loads recorded from the fracture tests. It was found that by increasing the proportion of mode III in cracked road structures, the fracture resistance of HMA mixtures reduced significantly.

This study examines the influence of the weight percentage of large aggregates with maximum size dmax on the tensile strength and fracture toughness of concrete using a simple fracture mechanics model. The concrete mixes were grouped according to the content by weight of large aggregates with dmax of 15%, 30%, 45%, 60% and 100% relative to the total coarse aggregates. For each group, three-point bending (3-p-b) specimens with different crack/depth ratios (0.1, 0.2, 0.3 and 0.4) were used to extract the tensile strength and fracture toughness of the concrete mixes and link them to the aggregate compositions and weight percentage of large aggregates. A boundary effect model (BEM) was used for the fracture analysis, which considers the heterogeneous aggregate structures in concrete by using a discrete number. The fictitious crack growth Δafic at the peak load Pmax is linked to the discrete number β and the maximum aggregate size dmax. The results indicate that the fracture toughness and tensile strength from the BEM exhibited the highest value for the group of 45% large aggregates with dmax. At the same time, a similar trend was observed in the change in β with varying percentage of aggregates with dmax. The fact that the average value of β from different groups led to reasonable predictions about tensile strength, fracture toughness and thus the peak load for the 3-p-b beams reveals that the influence of the amount of large aggregates with dmax on β could be ignored.

This paper proposes a practical method for addressing the effects of low temperatures on the ductile fracture behavior of high tensile strength steel plates and modeling using large shell finite elements. The test data of marine high-tensile strength steel grades, DH32, DH36, and EH36, at sub-zero temperatures were utilized. The tensile tests at sub-zero temperatures were simulated using fine solid elements to identify hardening law parameters. Simple localized necking loci were derived using the hardening curves of the steel grades considered. By defining the onset of localized necking as a failure condition, a simple fracture model for large shell finite elements that consider the low temperature effect was proposed. Several case studies were included to demonstrate the application and limitations of the proposed model.

To compare the clinical outcomes of a single three-dimensional (3-D) anatomical plate versus two conventional straight miniplates for the open treatment of mandibular subcondylar fractures.This retrospective clinical study included patients with mandibular subcondylar fractures treated by the retromandibular transparotid approach using a 3-D plate or two straight miniplates. Outcome variables included preoperative conditions of patients and fractures, extent of postoperative bone healing, and incidence of complications. Other variables included age, sex, fracture site, and follow-up duration. Variables were evaluated using descriptive statistics and compared between groups.Twenty-eight fractures were analyzed: 13 fractures using 3-D plate and 15 fractures using two straight miniplates. None of the assessed variables showed significant differences between the two groups (p 0.05). Unfortunately, in the 3-D plate group, reoperation was necessary for nonunion owing to plate breakage in one case with a bone defect around the fracture.The 3-D plate and two straight miniplates were equally effective for the surgical management of mandibular subcondylar fractures. Although a 3-D plate is sufficient for a typical simple fracture, in cases with a bone defect around the fracture, selection of the plate fixation method should be carefully considered.

This paper aims to observe fracture healing quality in rabbits after cerebral injury and compare it with the subcutaneous fracture healing. Purebred New Zealand white rabbits are randomly chosen as two groups, i.e. fracture merge brain injury group and simple fracture group. For the latter group: under the anesthesia, saw the right ulnar midpiece off rabbit, build a standard right ulnar fracture model. For the former group, repeat the above procedure for right ulnar fracture model, a linear acceleration brain injury model is also built. After anesthesia, place a stainless-steel gasket between the coronal and lambdoidal sutures, wait until the rabbit fully awakens, let it lie prostrate on a sponge mat, and then fall down from a height. The results show that bone mineral density of the fracture merge brain injury group is higher than that of simple fracture group. It is concluded that the healing quality of the fracture merge brain injury group is significantly better than that of simple fracture group. Hence one can see that the high-quality nursing service model can effectively facilitate fracture healing of patients and accelerate the recovery of the function of the ill limb.

Nondisplaced and minimally displaced fractures of the radial head and neck are common injuries, yet the role of physical therapy (PT) in their treatment is unclear. The aim of this trial was to assess the need for formal PT following a simple fracture of the radial head or neck.Patients who had a nondisplaced or minimally displaced fracture of the radial head or neck and presented to 1 of 2 providers were enrolled prospectively between January 2014 and August 2016. Patients were randomized to receive outpatient PT or perform self-directed home exercise. The follow-up intervals were 6 weeks, 3 months, 6 months, and at least 1 year. The outcome measures were Disabilities of the Arm, Shoulder and Hand (DASH) scores; pain; time to clinical healing; and range of motion. Demographic data were analyzed using the Mann-Whitney U test and Fisher exact test. Independent-samples t tests were utilized to compare outcome measures.Fifty-one patients were enrolled in the study. The average follow-up was 16.6 months. Twenty-five patients were randomized to a home-exercise cohort, and 26 patients were randomized to a formal-outpatient-PT cohort. There were no significant differences in demographics between cohorts. At 6 weeks, the home-exercise cohort had better function as indicated by a significantly lower mean DASH score compared with the PT cohort (p = 0.021). At 3 months, 6 months, and final follow-up, there were no significant differences between cohorts for any outcome measure.Patients who performed home exercises after sustaining a nondisplaced or minimally displaced fracture of the radial head or neck demonstrated better early function at 6 weeks compared with patients who received formal PT. After 6 weeks, there were no significant differences in outcomes. These data suggest that prescribing PT for patients who have an isolated nondisplaced or minimally displaced fracture of the radial head or neck is not cost-effective and that instructing the patient to perform self-directed exercises will be followed by a similar outcome.Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Using a direct reduction method, the fracture site is visualized greatly increasing the likelihood of an anatomic reduction in simple fracture patterns. In contrast, the fracture site is commonly not visualized during indirect reductions, and the surgeon relies on various methods to ensure restoration of accurate length, alignment, and rotation. The benefits of indirect reduction methods include decreased soft tissue dissection and less stripping of periosteal blood supply, with the goal of improving fracture healing and decreasing soft tissue wound complications. Because indirect reduction methods are being increasingly used, methods to assess fracture reduction have become vitally important.

To replace damaged cartilage or bone tissues, hydrogels are required to provide appropriate stiffness or deformation properties as well as resistance to fracture. However, failure properties, such as the resistance to fracture, must be evaluated by fracture toughness techniques. The application of the micro-destructive indentation test for fracture toughness determination in these tissues can become widespread because of the simplicity of the test. The aim of this paper is to propose a well-tested and more realistic approach for estimating fracture toughness in cartilage and bone.

This study has two purposes: (1) to compare the clinical results between the Titanium Elastic Nail (TEN) and plate fixation of the displaced midshaft clavicle fracture; and (2) to demonstrate the relationship between length shortening and functional outcome after TEN fixation, especially in the comminuted fracture pattern. A retrospective, case-controlled study was conducted and 55 patients were included in our study: 25 in the TEN fixation group (TEN group) and 30 in the plate fixation group (plate group). All patients were classified into four subgroups: simple fracture in the TEN group (ST; n = 13), simple fracture in the plate group (SP; n = 15), comminuted fracture in the TEN group (CT; n = 12), and comminuted fracture in the plate group (CP; n = 15). Wound size was significantly smaller in the TEN group (p

Background: This retrospective comparative study aims to evaluate the surgical outcomes and complications of two surgical methods for simple fractures of the humeral shaft; minimally invasive anterior plating and open reduction combined with internal fixation. Methods: A total of 26 patients with humeral shaft simple fractures, who had surgery between June 2009 and September 2013 and were followed-up at least 12 months, were included in our analysis. They were divided into two groups; group 1 comprised of 12 patients who underwent minimally invasive anterior plating and group 2 comprised of 14 patients who underwent an open reduction and internal fixation. The clinical outcomes, radiological results, and complications were compared and analyzed. Results: We found that bone union was achieved in all patients, and the mean union periods were 20.7 ± 3.34 and 20.3 ± 3.91 weeks for groups 1 and 2, respectively. In most patients, we found that shoulder and elbow functions were recovered. At 12 months post-operation, we found that the Korean Shoulder Scoring system, the University of California at Los Angeles score and Mayo elbow performance score were 91.4 ± 7.97, 33.4 ± 1.15, and 90.8 ± 2.23 for group 1, and 95.2 ± 1.53, 33.3 ± 1.43, and 90.17 ± 1.85 for group 2. In terms of complications, we found that 2 patients had radial nerve palsy after open reduction and internal fixation, but all cases spontaneously resolved within 6 months. Complications such as infection and loss of fixation were not reported. Conclusions: Both minimally invasive anterior plating and open reduction with internal fixation produced satisfactory outcomes in the treatment of simple fractures of the humeral shaft.

Patella fracture fixation remains a significant challenge for orthopedic surgeons. Although tension band fixation allows for reliable osseous union, especially in simple fracture patterns, it still presents several problems. Plate fixation of patella fractures is a method that allows for more rigid stabilization and earlier mobilization. At the authors' level 1 trauma center, one fellowship-trained trauma surgeon has transitioned to using a novel anterior, low-profile mesh plate construct for all types of patella fractures. This construct allows for stable fixation, osseous union, and neutralization of the inferior pole for even the most comminuted of patella fractures. [ Orthopedics. 2017; 40(4):e739–e743.]

Objective: To evaluate the frequency of deltoid ligament injury in bimalleolar supination-external rotation type fractures and whether there is a correlation between the size of the fractured medial malleolus and deltoid ligament injury . Methods: Twenty six consecutive patients underwent magnetic resonance exams after clinical and radiographic diagnosis of bimalleolar supination-external rotation type ankle fractures . Results: Thirteen patients (50%) presented deltoid ligament injury associated to bimalleolar ankle fracture. Partial injury was present in seven (26.9%) patients and total injury in six (23.1%). Regarding medial fragment size, the average was 2.88 cm in the absence of deltoid ligament injury. Partial injuries presented 1.93 cm and total 2.1 cm on average . Conclusion: Deltoid ligament injury was present in 50% of bimalleolar ankle fractures. Smaller medial malleolus fragments, especially concerning the anterior colliculus, presented greater association with partial deltoid ligament injuries. Level of Evidence IV, Cross Sectional Study. RESUMO Objetivo: Avaliar a frequência da lesão do ligamento deltóide nas fraturas bimaleolares do tornozelo tipo supinação-rotação externa e se existe correlação entre o tamanho do fragmento do maléolo medial fraturado e o tipo de lesão do ligamento deltóide. Métodos: Vinte e seis pacientes consecutivos com diagnóstico clínico e radiográfico de fratura bimaleolar do tornozelo tipo supinação-rotação externa (Lauge-Hansen), foram submetidos ao exame de ressonância magnética do tornozelo para avaliar a presença de lesão ligamentar associada à fratura bimaleolar. Resultados: Treze pacientes (50%) apresentaram lesão do ligamento deltóide associada à fratura bimaleolar do tornozelo, sendo sete (26,9%) lesões parciais e seis (23,1%) totais. Com relação ao tamanho do fragmento do maléolo medial, na ausência de lesão do ligamento deltóide, o tamanho médio foi de 2,88 cm. Nas lesões parciais, a média foi de 1,93 cm e, nas lesões totais do ligamento deltóide, de 2,1 cm. Conclusões: A lesão do ligamento deltóide esteve presente em metade das fraturas bimaleolares do tornozelo do tipo supinação-rotação externa. Fragmentos menores do maléolo medial, especialmente do colículo anterior, tem maior associação com lesões parciais do ligamento deltóide. Nível de Evidência IV, Estudo Transversal.

It is essential to study nuclide transport with underground water in fractured rock masses in order to evaluate potential radionuclide leakage in nuclear waste disposal. A time-domain random-walk (TDRW) method was firstly implemented into a discrete element method (DEM), that is, UDEC, in this paper to address the pressing challenges of modelling the nuclide transport in fractured rock masses such as massive fractures and coupled hydromechanical effect. The implementation was then validated against analytical solutions for nuclide transport in a single fracture and a simple fracture network. After that, the proposed implementation was applied to model the nuclide transport in a complex fracture network investigated in the DECOVALEX 2011 project to analyze the effect of matrix diffusion and stress on the nuclide transport in the fractured rock masses. It was concluded that the implementation of the TDRW method into UDEC provided a valuable tool to study the nuclide transport in the fractured rock masses. Moreover, it was found that the total travel time of the nuclide particles in the fractured rock masses with the matrix diffusion and external stress modelled was much longer than that without the matrix diffusion and external stress modelled.

Open fractures of the lower extremity cover a wide gamut of injuries ranging from the mangled, pulseless leg necessitating amputation to the more innocuous pinhole open wounds associated with simple fracture patterns. Prompt diagnosis and appropriate care can make a dramatic difference in decreasing complication rates and improving ultimate outcomes. Principles of management of open fractures have been created with the main goal of decreasing infection rates, while providing for stabilization of the bone and soft tissue injury.

Facial injuries frequently occur in traffic accidents involving motorcycles. The purpose of this study was to determine the prevalence of facial injuries among motorcycle drivers who perform motorcycle taxi service. The study design was cross-sectional. A total of 210 participants who served as motorcycle taxi drivers in a city in northeastern Brazil completed a survey concerning their experience of accidents involving facial injuries and consequent hospitalization and absenteeism from work. The motorcycle drivers included in the study were randomly selected from a list provided by the city. Out of the re- spondents, 165 (78.6%) who were involved in traffic accidents in the last 12 months, 15 (9.1%) reported facial injuries. The types of facial injury most frequently reported involved soft tissues (n ¼ 8; 53.3%), followed by simple fracture (n ¼ 4; 26.7%) and dentoalveolar fracture (n ¼ 3; 20%). We found an asso- ciation between facial injuries and absenteeism, as well as an association between the presence of facial injury and the need for hospitalization for a period of 2 days or more. Respondents reported that they had accidents, but due to the use of full face motorcycle helmet the number of facial injuries was low. For most of them, absenteeism was observed for a period of one month or more.

Nature Science Foundation of China [51275177, 51105144, 51105387]; Nature Science Foundation of Guangdong Province [S2012010008626]

In the lower extremity, compartment syndrome has been associated with fractures of the tibial plateau, shaft, and plafond. The patient was an 89-year-old male driver involved in a T-bone type motor vehicle accident. He sustained a closed transverse fibular shaft fracture and initially had fullness in his anterior/lateral compartments but no pain with passive and active range of motion of his ankle. Because of previous cardiac stenting, he was on dual anticoagulation therapy. Serial examination demonstrated tense compartments with notable pain during ankle range of motion. He was taken emergently to the operating room for four-compartment fasciotomies. On postoperative day 2, he returned to the operating room for débridement and underwent primary closure. The remainder of his hospital course was normal. Two-month follow-up did not demonstrate any compartment syndrome sequelae. In conclusion, patients on dual anticoagulation therapy are at a higher risk of developing compartment syndrome secondary to high-energy trauma, despite simple fracture patterns.

Purpose: The purpose of this study is to evaluate the clinical and radiological outcomes of treatment of humerus shaft simple fracture by minimally invasive percutaneous osteosynthesis (MIPO) technique using locking compression plate (LCP). Materials and Methods: Six patients who were operated for humerus shaft simple fracture from August 2010 to May 2011 were enrolled for this study. We checked the cause of injury and the accompanying injuries and evaluated the operation time, the clinical and radiological period of union, postoperative range of motion of the shoulder and elbow joint, pain, activities in daily living, radiologic alignment, and other complications. Results: The clinical period of bone union was 7.2 weeks on average, and the radiologic period of bone union was 8 weeks on average. Follow-up period was more than 12 months in all cases. The angulation through postoperative alignment was 2.8 degrees in AP view and 2 degrees in lateral view. The postoperative range of motion was 167 degrees in forward flexion, 50 degrees in external rotation, and thoracic vertebra 12 level in internal rotation. The average value of visual analogue scale (VAS) was 1.2 and that of KSS was 91.3. The American Shoulder and Elbow Surgeons’ score (ASES) was 26.5 and the UCLA score was 31.5. Conclusion: MIPO technique for the humerus shaft simple fracture showed good functional and radiological outcomes and may be considered as one of the treatment options for humerus shaft simple fracture.

This paper presents a simple approach to predict the failure of steel structures under the interaction effect of fracture and fatigue which is termed as ultra-low cycle fatigue (ULCF) failure. The approach mainly consists of simple fracture criterion, which is obtained from further simplification of available cyclic void growth model (CVGM). As for alternative component of ULCF analysis, a simple non-linear hardening model is proposed to employ in elasto-plastic analysis for situations where parameters of available mix hardening models (combined isotropic and kinematic hardening models) are difficult to determine. Initially the simplified ULCF fracture criterion is clearly presented and associated ULCF fracture prediction methodology is also indicated. Then the elasto-plastic hardening model is proposed and model behavior is compared with experimental behavior of few materials. The procedure to determine hardening constants and finite element (FE) formulation are also clearly mentioned. The simplified approach is then employed to determine ULCF fracture of some structural models. Hence verification of the simplified approach is confirmed by comparing the results with previous approaches-based estimations. Finally, study tends to conclude that the simplified approach produces reasonable accurate prediction to ULCF fracture of steel structures where magnitude of triaxiality remains relatively constant. Further, it was able to prove that commonly available elasto-plastic FEM packages can be reasonably employed to estimate ULCF fracture of steel structure when simplified ULCF fracture criterion governs the failure.

Purpose: The purpose of this study is to evaluate the difference between open reduction and internal fixation (ORIF) and intermaxillary fixation (IMF) of mandibular fractures. Methods: A total of one hundred twenty-seven patients who were treated for mandibular fractures at Chosun University Dental Hospital, from January 2008 to December 2010, and analyzed their prognoses based on the use of IMF at the time of fracture reduction. The patients were divided into two groups; the manual reduction group without IMF and IMF group. Results: After reduction of the mandibular fracture, good results were obtained with majority patients. Nonetheless, seven patients (13.0%) in manual reduction method without arch bars or IMF, developed complications after surgery. Three patients underwent IMF due to occlusal instability after surgery, while one patient underwent re-operation. Thus, a significant difference was not observed between the IMF and manual reduction groups. Conclusion: Manual reduction and IMF at mandibular simple fracture could produce good results. In case of mandibular simple fracture, it was recommended with only manual reduction without IMF or IMF during a short period.

Crown-root fractures in primary teeth are rare, with a wide variation of patterns that make diagnosis and treatment difficult. The aim of this study was to present a case series of crown-root fractures in primary teeth of children who attended a reference center. The study followed 28 cases of crown-root fractures in 26 children, representing 4% of the total number of attendees over 11 years of reference service at the Universidade Federal de Pelotas, Pelotas, Brazil. In most cases, the maxillary central incisors (85.7%) were involved. In the crown, 57.1% of the cases had a simple line of fracture, and 42.9% had multiple lines. Simple lines predominated in the root (89.3%). In cases with simple fracture lines in the crown, 37.6% underwent a total extraction, 31.2% required a partial extraction and 31.2% underwent pulpectomy. In most teeth with multiple lines of fractures in the crown, total extraction was performed (91.7%) All cases were followed-up until the eruption of the permanent successor tooth, and all patients had favorable outcomes. Resumo Fraturas coronorradiculares em dentes decíduos são raras, com uma ampla variação de padrões que dificultam o diagnóstico e tratamento. O objetivo deste estudo foi apresentar uma série de casos de fraturas coronorradiculares na dentição decídua de crianças atendidas em um centro de referência. O estudo acompanhou 28 casos de fratura coronorradicular em 26 crianças, representando 4% do número total de participantes ao longo de 11 anos no serviço de referência na Universidade Federal de Pelotas. Na maioria dos casos, o incisivo central superior (85,7%) foi o mais envolvido. Na coroa, 57,1% dos casos tiveram linha de fratura simples, e 42,9% tiveram múltiplas linhas. As linhas simples predominaram na raiz (89,3%). Nos casos com linhas de fratura simples na coroa, 37,6% foram submetidos à extração total, 31,2% necessitaram de extração parcial e 31,2% de pulpectomia. A maioria dos dentes com múltiplas linhas de fratura na coroa, a extração total foi realizada (91,7%). Todos os casos foram acompanhados até a erupção do dente permanente sucessor, e todos os pacientes tiveram resultados favoráveis.

This work reports the development of a simple mechanistic fracture model based on a modified Paris’ law using the J-integral. An internal damage parameter, namely the fracture index (FIc), was calculated from this model and was used as an index for ranking the fracture performance of different hot mix asphalt materials tested in fatigue. The relaxation test coefficient (m) and the dissipated pseudo strain energy for the fine aggregates matrix (FAM) volume were used as fundamental parameters for deriving this model. The study revealed there is compatibility between the FIc and phenomenological approach using the number of load cycles at failure. In this work, limestone and granite aggregates were used with two binder grades: 40/60 and 160/220 to prepare four mixtures with two different gradations: gap-graded hot rolled asphalt and continuously graded dense bitumen macadam. The study showed that limestone mixes perform better in fracture than their granite counterparts.

Development of advanced ceramics such as silicon carbide has gained significant importance because of their desirable properties. However, their engineering applications are still limited owing to the limitations in developing damage-free and economical machining techniques. It is often desired to increase the machining rate to improve productivity while maintaining the desired surface integrity. The success of this approach, however, requires a fundamental understanding of the material removal and damage formation mechanism in grinding. In this paper, high removal rate grinding of silicon carbide was investigated with respect to material removal and basic grinding parameters using a diamond grinding wheel. The results showed that the material removal was primarily due to the microfracture and grain dislodgement under the grinding conditioned selected. For grain dislodgement removal mode, the relationship for the removal rate in scratching based on a simple fracture mechanics analysis has been established. This research provides valuable insights into the surface and subsurface integrity and material removal mechanism during high removal rate grinding of silicon carbide.

A large fossilized crocodilian left femur recovered from the Pliocene Chinchilla Local Fauna of southeastern Queensland, Australia, exhibits a region of proliferative bone, consistent with an episode of osteitis. The nature and location of the pathology suggest a simple fracture with puncture wounds, possibly the result of a crushing bite of another crocodile, followed by infection. The size and morphology of the femur most closely resembles the now extinct Plio-Pleistocene crocodile Pallimnarchus.