Short Plate Research Articles

A randomized clinical study to evaluate the plate rod fixation for diaphyseal femoral fracture in dogs

The study was conducted to evaluate clinical effect of working length and rod size for plate rod fixation of diaphyseal femoral fracture repair in dogs. Twenty four dogs with femur fracture were randomly divided into four Groups viz. A, B, C and D having six animals in each group. Three bicortical screws in proximal and three in distal fragments with minimum two empty holes at the center were fixed for short plate working length (SPWL) in Groups A and B with intramedullary rod (IMR) occupying 30% and 40% of medullary canal, respectively. Two bicortical screws in proximal and two in distal fragments were fixed with minimum four empty holes at the center for long plate working length (LPWL) in Groups C and D with IMR occupying 30% and 40% of medullary canal, respectively. Fracture healing progress in all the Groups was assessed using clinical, photographic and radiographic observations. All the Groups showed good functional, radiographic outcome at the end of 14 week post-surgery. The time taken to show complete mobility and weight bearing was non-significantly less in Groups A and B. The functional, radiographic and outcomes of repair were excellent in Groups A and B without any major complications. Short plate working length with IMR occupying 40% of medullary canal of plate rod fixation provided comparatively better stability with fewer complications for femoral fracture repair in dogs.

RELATIONSHIP OF THE TRICEPS TENDON AND OLECRANON PLATES: AN ANATOMIC STUDY

Olecranon plates used for the internal fixation of complex olecranon fractures are applied directly over the triceps tendon on the posterior aspect of the olecranon. The aim of the study is to describe the relationship of the plates and screws to the triceps tendon at the level of the olecranon.Eight cadaveric elbows were used. Dimensions of the triceps tendon at the insertion and 1cm proximal were measured. A long or a short olecranon plate was then applied over the olecranon and the most proximal screw applied. The length of the plate impinging on the tendon and the level of the screw tract on the tendon and bone were measured.The mean olecranon height was 24.3cm (22.4-26.9cm) with a tip-to-tendon distance of 14.5cm (11.9-16.2cm). The triceps tendon footprint averaged 13.3cm (11.7-14.9cm) and 8.8cm (7.6-10.2cm) in width and length, respectively. The mean width of the central tendon 1 cm proximal to the footprint was 6.8 cm. The long olecranon plate overlay over more movable tendon length than did the short plate and consequently the superior screw pierced the triceps tendon more proximally with the long plate. Using the Mann-Whitney U test, the differences were significant.The long olecranon plates encroach on more triceps tendon than short plates. This may be an important consideration for olecranon fractures with regards implant loosening or triceps tendon injury.

Passive control of wake flow behind a square cylinder using a flat plate

In this study, control over the wake flow of a single square cylinder exercised by a flat plate attached to the rear side of the cylinder is analyzed numerically via the lattice Boltzmann method. The Reynolds number (Re) is fixed at 150, and the length of the plate is varied from 0.1 to 8.5. Three distinct flow modes are observed in this study: unsteady, transient, and steady flow in the cases of plate lengths (L) in the ranges 0.1 ≤L≤ 6.5, 6.75 ≤L≤ 7.5, and 7.75 ≤L≤ 8.5, respectively. The streamlines exhibit different flow structures, termed hairpin-like, ellipse-like, and elongated bubble-like, at different values of L. Complete wake control is achieved at plate lengths beyond 7.75. This study reveals that the drag and lift coefficients exhibit unsteadiness at short plate lengths in early time steps, but as the plate length increases, unsteadiness slows down and eventually disappears, confirming the steady flow pattern. The mean drag coefficient (CDm), Strouhal number (St), and root-mean-square value of drag and lift coefficients (CDrms; CLrms) are reduced by maximums of 23.5%, 100%, 84.6%, and 99.5%, respectively, as a result of the presence of the plate.

Fatigue Repair of Cracked Steel Plates Using Small-Patch Ultrahigh-Modulus CFRP Governed by Bond Failure

This study evaluates the effectiveness of externally bonded small-patch ultrahigh-modulus (UHM) carbon fiber–reinforced polymer (CFRP) plates of 460 GPa modulus in extending fatigue life and slowing crack propagation in steel plates with simulated fatigue cracks. The study investigates a range of very short bond lengths for applications where bonding space may be limited or accessibility restricted, together with the effect of single- versus double-sided application, on fatigue performance. It also compares short UHM CFRP plates with similar length normal modulus (NM) (165 GPa) CFRP plates with regard to extending fatigue life and reducing stress concentration at the crack tip. Distributed fiber-optic sensors (DFOS) and digital-image correlation (DIC) are used to capture the full strain field and track crack growth. Results showed that fatigue life was increased by up to 2.0 and 2.34 times for single- and double-sided UHM CFRP repairs. As bond length increased from 25 to 100 mm, fatigue life increased from 1.36 to 2.0. UHM CFRP more effectively reduced stress concentration at the crack tip, by 60% compared with 37% for NM CFRP, indicating that it has the potential for superior fatigue life gains, relative to NM CFRP if the necessary bond length to prevent or delay debonding is provided. As debonding failure governed in this study, NM CFRP plates achieved comparable fatigue life extension. DIC tracking of crack growth matched the traditional “beach marking” technique with less than 6% difference.

Feasibility analysis of fixed plates in chord-dominated dynamic ground effect wind tunnel experiment

The dynamic ground effect (DGE) refers to the take-off and landing process where the distance between airplane and ground constantly changes with time. In the wind tunnel experiment of DGE, fixed plates are often adopted to substitute the moving-belt ground, which will affect experimental reliability. In this paper, the landing process of an airfoil is simulated to study the feasibility of fixed plates in the chord-dominated DGE experiment. The height is divided into two regions based on the aerodynamics and flow patterns. In Region I (large height), DGE is dominated by the static ground effect (SGE), using a fixed plate can effectively balance the camber effect, blocking effect and boundary layer effect to reproduce result of the moving-ground condition. In Region II (small height), DGE is dominated by the compression work effect, where the downwash is highly compressed to diverge into a forward stream and a backward stream. When using fixed plates, the downwash exhibits two kinds of escaping behavior: the leading-edge-preferred escaping behavior for most fixed plates due to thick boundary layer and the trailing-edge-preferred escaping behavior for the very short plate due to the suddenly weakened camber effect. No plate can balance the two kinds of flow to accurately reproduce pressure distribution on airfoil lower surface and flow physics of moving-ground condition. Thus, the use of a fixed plate is infeasible.

Flow control of an elastically mounted square cylinder by using an attached flexible plate

This work numerically investigates the flow control of an elastically mounted square cylinder by using an attached plate placing downstream. The flow control effect by using a long solid/flexible plate for a circular cylinder has been widely discussed. However, the effect of a short plate is not clear. In addition, few knowledge is known for VIV (vortex-induced vibration) suppression effect for a square cylinder by using a solid/flexible plate. The present work systematically studies the influence of plate length and flexibility on VIV suppression for an elastically mounted square cylinder at Reynolds number 150. First, the effect of a solid plate with non-dimensional length varying in a wide range 0.5≤L*≤3.0 is analyzed. Significant VIV suppression can be achieved by using an attached solid plate, even with a plate at a short length. The influence of flexibility is more complex. A short flexible plate is less effective than a solid plate with the same length. On the other hand, a long flexible plate with medium flexibility can further enhance VIV suppression. A maximum 96% reduction in the vibration amplitude can be achieved by using a long flexible plate with optimal flexibility. Additionally, two VIV suppression mechanisms for an elastically mounted square cylinder with an attached plate are concluded, and the influence of flexibility for both short and long plates is also analyzed.

Minimally Invasive Plating of Distal Radius Fracture: A Series of 42 Cases and Review of Current Literature.

Surgical techniques developed for distal radius fracture fixation have become increasingly advanced, including minimally invasive plate osteosynthesis (MIPO). This study aimed to introduce and evaluate the functional outcome of a novel MIPO technique that differs from previous reports. This study included 42 patients with distal radius fractures who underwent minimally invasive surgical plating of the distal radius. All patients were treated with closed reduction, fixation using K-wire, and subsequent insertion of a volar anatomical stable angle short plate on the distal radius. An arthroscopy-assisted evaluation and repair procedure were performed to correct intra-articular involvement, triangular fibrocartilage complex tears, and scapholunate injuries. Functional outcomes were assessed using a visual analog scale score; quick disabilities of the arm, shoulder, and hand score; and postoperative range of motion of flexion, extension, supination, and pronation at the 3-month follow-up, showing significant improvement in all parameters (all p ≤ 0.05). This study provides a simpler yet reliable method with reproducible and consistent results to treat distal radius fractures using minimally invasive plating with closed reduction and plate insertion, resulting in satisfactory clinical outcomes in all patients.

Method of difference-differential equations for some Bethe-ansatz-solvable models

In studies of one-dimensional Bethe ansatz solvable models, a Fredholm integral equation of the second kind with a difference kernel on a finite interval often appears. This equation does not generally admit a closed-form solution and hence its analysis is quite complicated. Here we study a family of such equations, concentrating on their moments. We find exact relations between the moments in the form of difference-differential equations. The latter results significantly advance the analysis, enabling one to practically determine all the moments from the explicit knowledge of the lowest one. As applications, several examples are considered. First, we study the moments of the quasimomentum distribution in the Lieb-Liniger model and find explicit analytical results. The latter moments determine several basic quantities, e.g., the $N$-body local correlation functions. We prove the equivalence between different expressions found in the literature for the three-body local correlation functions and find an exact result for the four-body local correlation function in terms of the moments of the quasimomentum distributions. We eventually find the analytical results for the three- and four-body correlation functions in the form of asymptotic series in the regimes of weak and strong interactions. Next, we study the exact form of the low-energy spectrum of a magnon (a polaron) excitation in the two-component Bose gas described by the Yang-Gaudin model. We find its explicit form, which depends on the moments of the quasimomentum distributions of the Lieb-Liniger model. Then, we address a seemingly unrelated problem of capacitance of a circular capacitor and express the exact result for the capacitance in the parametric form. In the most interesting case of short plate separations, the parametric form has a single logarithmic term. This should be contrasted with the explicit result that has a complicated structure of logarithms.

Influence of plate size and screw distribution on the biomechanical behaviour of osteosynthesis by means of lateral plates in femoral fractures

Distal femoral fractures are fractures associated with high rates of morbidity and mortality, affecting to three different groups of individuals: younger people suffering high-energy trauma, elderly people with fragile bones and people with periprosthetic fractures around previous total knee arthroplasty. They have been classically treated with conventional plates and intramedullary nails and more recently with locked plates that have increased their indications to more types of fractures. The main objective of the present work is the biomechanical study, by means of finite element simulation, of the stability achieved in the osteosynthesis of femoral fractures in zones 4 and 5 of Wiss, by using locked plates with different plate lengths and different screw configurations, and analysing the effect of screw proximity to the fracture site. A three dimensional (3D) finite element model of the femur from 55-year-old male donor was developed, and then a stability analysis was performed for the fixation provided by Osteosynthesis System LOQTEC® Lateral Distal Femur Plate in two different fracture zones corresponding to the zones 4 and 5 according to the Wiss fracture classification. The study was focused on the immediately post-operative stage, without any biological healing process. The obtained results show that more stable osteosyntheses were obtained by using shorter plates. In the cases of longer plates, it results more convenient disposing screws in a way that the upper ones are closer to fracture site. The obtained results can support surgeons to understand the biomechanics of fracture stability, and then to guide them towards the more appropriate osteosynthesis depending on the fracture type and location.

A New Genus and Species of the Suborder Trogiomorpha (Insecta, Psocodea) from Mid-Cretaceous Amber of Myanmar.

We established a new genus with a new species Brachyantennum spinosum Liang et Liu, gen. et sp. nov. from mid-Cretaceous Burmese Kachin amber. It is tentatively placed into the suborder Trogiomorpha, based on the strong external valve, the reduced dorsal and ventral valve, and the short subgenital plate covering the basal part of the external valve. This new genus is apparently close to the family Cormopsocidae, based on the well-developed and very long hindwing Sc vein. However, its familial placement is ambiguous and it can be excluded from the established families of Trogiomorpha by the presence of the tarsal ctenidiobothria on the mid- and hindleg.

Mathematical modeling of inhomogeneous electric field impact on a liquid crystal layer

AbstractThe authors analyze the Fréedericksz transition phenomenon of reorientation of molecules in the plane liquid crystal layer in inhomogeneous electric field generated by parallel plate capacitor using the Oseen–Frank mathematical model. The capacitor is a set of short metal plates periodically located on both sides of the extended liquid crystal layer, connected in series in two circuits. When electric charges of different signs appear on opposite plates of the capacitor, the electric field in the periodicity cell turns out to be significantly inhomogeneous both in length and in thickness of the layer. Governing equations of the model represent Euler's variational equations in the problem on minimization of the potential energy of liquid crystal. Numerical solution of the equations uses the authorial variational difference scheme. The Laplace equation for electric potential in the exterior of the liquid crystal layer is solved using the method of lines. The electric field and the patterns of orientation angles of molecules inside the layer are determined by iterating with numerical solution of Poisson's equation using the fast Fourier transform at each iteration step. The algorithm is implemented by means of CUDA technology for computing systems with graphics accelerators. The scale of the mesh to ensure the computation accuracy is selected from calculation of Tsvetkov's order parameter in a rectangular cell pattern. Verification of the algorithm and program is implemented by way of comparing the computational results and the exact solution of the problem on the homogenous electric field with the constant initial orientation angle of liquid crystal molecules. The computations accomplished yield the patterns of the electric potentials and orientation angles of molecules depending on the position of the capacitor plates at uniform and s‐shaped initial distribution of the orientation angles through the thickness of the liquid crystal layer.

Biomechanical effects of different numbers and locations of screw-in clavicle hook plates.

Purpose: We sought to analyze the biomechanical effects which both different numbers and locations of screws have on three different clavicle hook plates, as well as any possible causes of sub-acromial bone erosion and peri-implant clavicular fractures. Methods: This study built thirteen groups of finite element models using three different clavicle hook plates (short plates, long plates, and posterior hook offset plates) in varying numbers and locations of the screws. The von Mises stress distribution of the clavicle and hook plate, as well as the reaction force of the acromion was evaluated. Results: The results show that inserting screws in all available screw holes on the hook plate produces a relatively large reaction force on the acromion, particularly in the axial direction of the bone plate. The fewer the screws implanted into the clavicle hook plate, the larger the area of high-stress distribution there is in the middle of the clavicle, and also, the higher the stress distribution on the clavicle hook plate. Conclusion: This study provides orthopedic physicians with the biomechanical analysis of different numbers and locations of screws in clavicle hook plates to help minimize surgical complications.

Risk factors for hardware-related complications after extra-articular distal humerus fracture fixation using an anatomical locking plate.

We aimed to identify the incidence and risk factors of hardware-related complications in patients treated with anatomical locking plate fixation for extra-articular distal humerus fractures. From 2013 to 2020, patients with extra-articular distal humerus fractures who underwent open reduction and internal fixation with an extra-articular distal humerus locking plate (EADHP) were retrospectively reviewed and categorized according to the presence/absence of hardware-related complications. Hardware-related complications were defined as the occurrence of skin prominence on the plate and discomfort in activities of daily living. Patient demographics, the lateral condylar angle, lateral body length, shaft-condylar angle of the humerus, and plate length were analyzed. Of the 29 patients, 10 (34%) did not develop hardware-related complications (group A), whereas 19 (66%) did (group B). Patient demographics did not differ between the groups. However, the number of patients who underwent hardware removal was significantly greater in group B (16/19) than in group A (4/10; p = 0.032). Radiologic assessment revealed no significant difference in the lateral condylar or shaft-condylar angle. However, the lateral body length was greater in group A than in group B (44.5 ± 4.8 vs. 39.5 ± 3.7, p = 0.007). The plate length significantly differed between the groups. Twelve of 19 (63%) patients in group B received short-hole plates (six holes), while nine of ten (90%) patients in group A received long-hole plates (eight holes). In the multivariable analysis, the lateral body length of the distal humerus (p = 0.047, odds ratio = 0.734, 95% confidence interval: 0.542-0.996) and plate length (p = 0.036, odds ratio = 0.076, 95% confidence interval: 0.542-0.996) were associated with hardware-related complications. Most patients developed hardware-related complications, particularly with short plates, mainly because of the narrow lateral body length of the distal humerus. Surgeons should be careful to secure EADHP in the appropriate position, especially when short plates are used in patients with narrow lateral body length.

Axial compression behavior of precast circular semi-continuous concrete-filled steel tube columns

To study the axial compression performance of precast circular semi-continuous concrete-filled steel tube (PCSCFST) column, a total of 17 specimens were prepared and tested, including 13 PCSCFST columns and 4 continuous CFST columns. This PCSCFST column is made up of upper and lower steel tubes and outer steel tubes connected by bolts, which has the advantages of easy factory production and convenient transportation. The results showed that shear failure occurred in continuous CFST columns, but not in PCSCFST columns, bolts had obvious influence on failure mode. Maintaining the consistency of the thickness of each steel tube on the specimen can not only improve the local buckling, but also avoid the short plate effect to give full play to the material performance. Moreover, with the increase of steel tube thickness, concrete strength, bolt diameter, reduction of specimen length and pure bolt connection instead of bolt and weld combination connection, the deformation resistance of bolts and axial compression performance of specimens had been enhanced. However, the increase of bolt diameter from 12 to 18 mm resulted in a better strength degradation rate, but worse bearing capacity and deformation resistance. Finally, the predictions of the ultimate bearing capacity of PCSCFST columns under axial compression agree well with the test results, the average value of Nexp/ Npre and the variance are 0.998 and 0.00111.

Surgical management of primary severe hypospadias in children: an update focusing on penile curvature.

Over the past two decades, assessment and treatment of associated curvature has emerged as a major issue in treating patients with proximal hypospadias. However, the cut-off for defining a curvature as clinically significant is still unclear, as not all patients are bothered by the same degree of curvature and, although the need for a method to assess the curvature objectively has been emphasized, no standard method yet exists. Curvature is multifactorial. The same degree of curvature can be due to any possible combination of skin and/or subcutaneous dartos tethering, a short urethral plate and an intrinsic corpora disproportion. Different strategies can be used to treat curvature, depending on the underlying cause, surgeon preferences, and the goals of the repair. In the past 10 years, use of urethral plate transection and ventral lengthening procedures has increased, although the lack of long-term follow-up data on ventral lengthening procedures suggests that the use of such procedures should be selective. Furthermore, straightening manoeuvres are influenced by the technique used for subsequent urethroplasty and, in turn, may influence the success rate of the urethroplasty. This Review provides a comprehensive overview of the major developments from the past 10 years in the management of severe proximal hypospadias in children.

Bio-mechanical analysis of plate system used for opening wedge high tibial osteotomy

The use of high tibial osteotomy (HTO) is to treat patients with varus deformity of the knee by shifting load from joint. The objective of this investigation was to analyze and compare the biomechanical behavior of five types of plate implant systems for opening wedge HTO. A validated finite element (FE) model was used to assess the biomechanical environment provided locally by five different designs of fixation plates. The HTO implants were inserted into gaps that was virtually added without any change in knee alignment. An axial compressive load of ∼ 3 times of body weight was used for analysis. The local biomechanical environment which is defined by stresses in bone and implant, was evaluated. Furthermore, total deformations of the implants were also calculated. The stress-induced in the long plates (∼148 and ∼ 132 MPa) was significantly high compared to other short plates. This study exhibited that the long plate implants system imparts better stability and least micro motion compared to other plate systems for HTO. The work also showed the application of finite element modeling for optimizing the design of HTO implants.

Plate Fixation for Atypical Fractures of the Femoral Diaphysis.

BackgroundPlate fixation for atypical femoral fractures has shown high failure rates compared to intramedullary nail fixation. The aim of this study was to evaluate the radiological results of patients treated with a plate and screws for atypical fractures of the femoral diaphysis.MethodsThis study was conducted retrospectively on 16 patients who had undergone internal fixation using plates for treatment of atypical femoral complete fractures from 2007 to 2015. Nine patients were treated with lag screws and short plates while 7 patients were treated with position screws and long plates, which covered the whole femur. Radiologic evaluation was performed on all patients. Complications were also evaluated.ResultsBone union was achieved in all patients and the average bone union time was 17.7 weeks (range, 14–28 weeks). There was no correlation between the preoperative use of a bisphosphonate, plate length, postoperative teriparatide use, and the time to bone union. Regarding complications, 2 cases of complete fractures and 1 impending fracture occurred at the end of short plates.ConclusionsSatisfactory results were obtained with use of plates for patients with atypical femoral complete diaphyseal fractures, in whom intramedullary nails could not be applied due to severe bowing. In particular, it seemed advantageous compared with intramedullary nail fixation in that it could maintain the leg length through anatomical reduction and prevent iatrogenic fracture.

Pre-contoured superior locking plates offer poor bone fit for midshaft clavicle fracture fixation: cadaveric analysis of 4 commercially available systems.

The goal of this study is to verify how commercially available pre-contoured superior plates fit on clavicle midshaft fractures. 100 cadaveric clavicles were evaluated by three distinct observers applying the clavicle congruence score and comparing four different 6 to 8-hole pre-contoured anatomic locking-plate systems. the inter-observer agreement was considered moderate by the percentage agreement and fair by the Fleiss' Kappa, with no significant differences between evaluations. Only 1 of the 8 plates presented an anatomic fit greater than 70%. Long plates (8 holes) presented a poor fit compared to short plates (6 or 7 holes). the overall evaluation showed that currently-available pre-contoured superior plate systems provide a poor fit on clavicles for midshaft fracture fixations. Long plates present a worse fit compared to short ones.

Peptidomic analysis characterising proteolysis in thaw-aging of beef short plate

Recent studies have suggested that thaw-aging can improve sensory attributes of freeze-thawed meat. Acceleration of proteolysis is expected to promote tenderisation and improve taste; however, the details of protein degradation, including substrate proteins and cleavage sites, remain unclear. Here, we report a time course overview of the peptidome of beef short plates during thaw-aging. The accelerated degradation of key proteins for meat tenderisation, such as troponin T and desmin, was confirmed. Additionally, 11 cleavage sites in troponin T related to taste-active peptide generation were identified. Terminome analysis showed that the contribution of each protease varies depending on the substrate proteins and the thaw-aging period. Based on our results; proteases, not only calpains, but also others contributed to the degradation of myofibrillar proteins. The techniques employed indicate that meat proteolysis during thaw-aging is not constant but dynamic.

Biomechanical analysis of the role of hinge support fixators on hinge stability in medial closing wedge distal femoral osteotomy

BackgroundThis study aimed to examine the hinge-stabilizing biomechanical effects of hinge support fixators, applied for lateral hinge fractures sustained following distal femoral osteotomy. MethodsMedial closing wedge distal femoral osteotomy was performed using a locking plate on 10 cadaveric limbs. The limbs were divided into two groups: the non-fracture group and the lateral hinge fracture group. A cyclic axial load of 400 N was applied to the knee to keep it extended and flexed at 45°. The hinge-stabilizing effects of adding a screw or a short support plate to the lateral fracture site were examined by measuring the translation and rotational angles of the anterodistal and posterodistal hinge positions as well as the surface strains of the medial locking plate. FindingsTranslation and rotation in the fracture group were significantly more pronounced than in the non-fracture group, at the anterodistal and posterodistal positions. Translations at both positions were significantly reduced, by adding the support plate, during both extension and 45-degree flexion in the fracture group. The rotation at the posterodistal position upon extension and the anterodistal position upon 45-degree flexion was significantly reduced by the support plate. The surface strain of the medial plate in the fracture group was significantly reduced by the support plate upon both extension and 45-degree flexion. InterpretationLateral hinge fractures caused abnormal hinge movements, which were significantly reduced by the short support plate. A short support plate could be used if a hinge fracture occurs during distal femoral osteotomy, to improve lateral hinge stability.