Compression Plate Research Articles

Periprosthetic Distal Femoral Fractures Around a Total Knee Arthroplasty: a Meta-analysis Comparing Locking compression Plating and Retrograde Intramedullary Nailing.

The number of total knee replacements (TKRs) performed per year has been increasing annually and it is estimated that by 2030 demand would reach 3.48 million procedures per year in the United States Of America. The prevalence of periprosthetic fractures (PPFs) around TKRs has followed this trend with incidences ranging from 0.3% to 3.5%. Distal femoral PPFs are associated with significant morbidity and mortality. When there is sufficient bone stock in the distal femur and a fracture pattern conducive to fixation, locking compression plating (LCP) and retrograde intramedullary nailing (RIMN) are commonly used fixation strategies. Conversely, in situations with loosening and deficient bone stock, a salvage procedure such as a distal femoral replacement is recognized as an alternative. This meta-analysis investigates the rates of non-union, re-operation, infection, and mortality for LCPs and RIMNs when performed for distal femoral PPFs fractures around TKRs. A search was conducted to identify articles relevant to the management of distal femoral PPFs around TKRs in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Articles meeting the inclusion criteria were then assessed for methodological quality using the methodological items for non-randomised studies (MINORS) criteria. Articles were reviewed, and data were compiled into tables for analysis. 10 articles met the inclusion criteria, reporting on 528 PPFs. The overall incidence of complications was: non-union 9.4%, re-operation 12.9%, infection 2.4%, and mortality 5.5%. This meta-analysis found no significant differences between RIMN and LCP in rates of non-union (9.2% vs 9.6%) re-operation (15.1% vs 11.3%), infection (2.1% vs 2.6%), and mortality (6.0% vs 5.2%), respectively. This meta-analysis demonstrated no significant difference in rates of non-union, re-operation, infection, and mortality between RIMN and LCP and both remain valid surgical treatment options.

Effect of glass compression plate on EBT-XD film dosimetry for pretreatment quality assurance of stereotactic body radiotherapy.

EBT-XD film specially designed for high dose verifications such as stereotactic treatments. The dose response of the film can be affected by several factors, the curly nature of the film being one of them. In this study this curly nature of the film was investigated for stereotactic body radiotherapy (SBRT) plan verifications. For this study, 18 SBRT (11 prostate, 3 spines, and 4 lungs) cases were enrolled. For all the cases, VMAT plans were created in the Monaco treatment planning system and plan was delivered in Elekta Versa HD linear accelerator and delivered fluence was captured by EBT-XD films. All films were scanned with and without a compression plate. All the films were analyzed using the single-channel film method using the red channel. A significant difference in the gamma passing rates (GPR) for the films scanned with and without the compression plate was observed. The maximum percentage differences in GPR between using and not using a compression plate were 12.7% for 1% 1 mm, 8.1% for 2% 2 mm, 7.5% for 3% 2 mm, and 5% for 3% 3mm criteria. Similarly, the mean %difference in GPR was 5.8% for 1% 1 mm, 2.4% for 2% 2 mm, 1.6% for 3% 2 mm and 0.96% for 3% 3 mm criteria. The results suggest that placing a compression plate over the film during scanning provided a great advantage in achieving a more accurate gamma passing rate irrespective of gamma criteria.

Autologous non-vascularized fibula with compression plating in the management of aseptic complex non-union of long bones.

The surgical treatment of non-union of long bones are challenging especially when bones are osteoporotic or there is a large bone gap due to repeated surgeries and implant failures. Plate with intramedullary fibula provides a stable construct as fibula acts as a second implant with better anchorage and high pull-out strength. The aim of our study is to present our experience of treating complex non-union of long bones using compression plating (LCPs/DCPs) in combination with autologous non-vascularized fibular graft (ANVFG). 10 cases of complex non-union of long bones (tibia, femur, humerus) treated with debridement, decortication followed by intramedullary fibular strut grafting and rigid osteosynthesis by LCPs/DCPs were included in this study. DASH score and LEFS score was used for upper limb and lower limb functional assessment. All patients had clinico-radiological union with a mean time of 11.4 months. Pre-operative mean DASH and LEFS score was 45.9±2.1 and 20.6±2.03 At the last follow-up, mean DASH and LEFS score was 19.8±1.1 and 60.6±2.6. Compression plating with ANVFG is a viable option for treating complex non-union of long bones. Intramedullary fibula acting as a second implant provides mechanical stability and support biological healing with its osteogenic property at the non-union site.

Исторические аспекты и тенденции в развитии хирургического лечения переломов

Annotation: We consider trends in the development of traumatology from the 19th century to the present. The prerequisites for the development of intramedullary osteosynthesis appeared in the late – early 20th centuries. But the rapid development of traumatology begins with the discovery of the principles of asepsis and antiseptics and X-rays, which allows doctors to resort to surgical treatment of fractures more often. The research purpose is to determine the historical aspects and the main directions of the development of traumatology in the treatment of bone fractures. Materials and methods. The search was conducted in the open electronic scientific databases PubMed and databases of the Russian scientific electronic library eLibrary with keywords and phrases: traumatology, osteosynthesis, history of osteosynthesis, transosseous osteosynthesis, intramedullary osteosynthesis. Results. The end of the 20th century marked the appearance of a large number of different plates for osteosynthesis (dynamic compression plate – DCP, locking compression plate – LCP, point-contact fixator – PC-Fix), widely used in modern surgical practice, and methods of application (minimally invasive osteosynthesis, the use of biodegradable materials). Conclusion. The main trends in the development of modern traumatology are based on minimizing surgical intervention with maximum preservation of the biological integrity of tissues and the earliest activation of the patient.

Influence of Preheat Temperature Variation on Single Screw Extrusion for Characterizing PLA, PCL, and HA Biocomposite Filaments

Fractures and ligament injuries often require bone fixation, commonly through Open Reduction and Internal Fixation (ORIF) with compression plates and screws. Additive manufacturing (AM) techniques are considered sustainable due to their potential to reduce emissions and have a minimal adverse impact on the environment. Currently, there is extensive research into producing biocomposite filaments, though there remains limited exploration of the impact of preheat temperature on filament properties. This research explores the effects of varying preheat temperatures in a single screw extruder to achieve biocomposite filament as candidate for biodegradable bone implants. Biocomposite filaments made from Polylactic Acid (PLA) and Polycaprolactone (PCL) in an 85:15 ratio, with 5% hydroxyapatite (HA) derived from green mussel shell waste. Biocomposite mixture was cut into sub-5mm fragments and extruded at 175°C with preheat temperatures between 159°C and 168°C. Filaments were used to fabricate specimens via a 3D printer, following ASTM D790 standards. Specimens were analyzed using X-Ray Diffractometer, Fourier Transform Infrared, Scanning Electron Microscope, density measurements, three-point bending tests, and biodegradation assessments. Results show that preheat temperature variations significantly affect the filament’s crystallinity index, impacting density and mechanical properties. Higher preheat temperatures result in a lower crystallinity index, decreasing density and potentially increasing degradation rates.

Clinical efficacy analysis of minimally invasive intramedullary nailing in the treatment of humeral shaft fractures combined with radial nerve injury.

The aim of this study was to research the therapeutic effectiveness of radial nerve damage paired with a humeral shaft fracture and intramedullary nailing. Retrospective research was performed on the medical records of 58 individuals who had humeral shaft fractures and radial nerve injuries. The admission period was between June 1, 2020, and June 31, 2022. All study subjects that satisfied the requirements for inclusion were separated, using the random number table approach, into two groups: one for internal fixation (group N), which included 29 cases, and one for minimally invasive procedures (group W), which included 29 patients. Group W received minimally invasive intramedullary nail treatment, and group N received internal fixation with compression plates. The changes in the clinical effects, surgery-related indicators, joint function, nerve function, and levels of stress indicators of the two groups of treatment were analyzed. The changes in adverse reactions and satisfaction of patients were compared. The effective rate of group W was 89.66% (26/29), and that of group N was 72.41% (21/29). Although group W's effective rate was higher than group N's, there was no discernible disparity between the two groups (p>0.05). Surgical blood loss and incision length were much smaller in group W than in group N, and overall operation duration and length of stay were considerably shorter in group W than in group N (p<0.05). The excellent and good rate of elbow joint function in group W was 93.10% (27/29), whereas the excellent and good rate of group N was 65.52% (19/29). The excellent and good rate of elbow joint function in group W was considerably greater than that of group N (p<0.05). In group W, the excellent and good rate of shoulder joint was 96.55% (28/29), and that in group N was 68.97% (20/29), and group W had a considerably greater probability of excellent shoulder joint function than group N (p<0.05); the excellent and good rate of neurological function was 82.76% (24/29) in group W and 58.62% (17/29) in group N, and group W had much greater rates of excellent and good neurological function than group N (p<0.05). prostaglandin E-2 (PGE2), C-reactive protein (CRP) and Substance P (SP) levels in the W group and the N group were substantially higher after the surgery than they were prior to it (p<0.05), and in the W group, the aforementioned stress markers were much lower than they were in the N group (p<0.05). Group W experienced a 3.45% (1/29) rate of adverse events, while group N saw a 24.14% (7/29) incidence. The incidence of adverse responses was substantially lower in group W than in group N (p<0.05). The contentment rate of group W was 93.10% (27/29), and that of group N was 72.41% (21/29). Group W had a much greater contentment percentage than group N (p<0.05). Minimally invasive intramedullary nailing is a successful therapeutic approach for humeral shaft fractures with radial nerve damage, which may successfully enhance patients' shoulder and elbow joint function and nerve function, reduce patients' stress response, and has the characteristics of minimal adverse responses and high contentment, which is worthy of popularization and deployment.

Beyond the Fracture: Managing Aseptic Ulnar Diaphyseal Non-Union in a Seizure Patient with Elastc Nail, Fibula Graft, and Locking Compression Plate: A Rare Case Report

Introduction: Aseptic ulnar diaphyseal non-union presents a complex challenge in orthopedic practice, particularly when compounded by concurrent seizure disorders. This case report highlights the unique considerations and innovative approaches in managing such cases, emphasizing the importance of interdisciplinary collaboration and tailored treatment strategies. Case Report: We present the case of a 35-year-old male with a history of recurrent ulnar fractures and generalized tonic-clonic seizures. Through a multidisciplinary approach involving orthopedics, neurology, and rehabilitation services, we successfully managed aseptic ulnar diaphyseal non-union while addressing the patient’s seizure disorder. Implant removal, fibula grafting, elastic nailing, and bridging fixation with a locking compression plate were employed, leading to favorable outcomes at the final follow-up. Conclusion: The management of aseptic ulnar diaphyseal non-union in patients with concurrent seizure disorders requires a nuanced and multidisciplinary approach. This case underscores the importance of individualized treatment strategies, interdisciplinary collaboration, and innovative surgical techniques in achieving successful outcomes. Sharing our experience aims to contribute to the existing literature and inform clinical practice in addressing similar challenging scenarios. Keywords: Aseptic non-union, ulnar fracture, seizure disorder, elastic nail, fibula grafting.

Functional Outcome of Distal Femoral Fractures using NEER Scoring Managed by Distal Femoral Locking Plate versus Retrograde Intramedullary Nail: A Cross-sectional Study

Introduction: Distal femur fractures are a group of fractures that have been a topic of debate for the past decade, were traditionally treated mainly using conservative methods. However, with advancements in surgical techniques and implants, operative intervention has now become the preferred treatment approach. There are various methods for treating distal femur fractures and the present study compares the treatment of distal femoral fracture using distal femur nailing versus the use of locking plate. Aim: To compare the functional outcomes of stabilising distal femur fractures using locking compression plating versus retrograde nailing and to evaluate the merits and drawbacks of each procedure. Materials and Methods: A cross-sectional comparative study was conducted in the Department of Orthopaedics at Calcutta National Medical College and Hospital, Kolkata, West Bengal, India, over a one-year period from (January 2021 to January 2022. Total 46 patients with distal femur fractures were included, with six lost to follow-up. Two groups were divided in which total 20 patients underwent distal femoral nailing, while 20 were treated with distal femoral locking plates. Functional outcomes were assessed using the NEER Score, aiming for perfect restoration of the articular surface, stable fixation, full knee range of motion, and good functional results. Data were entered into a Microsoft Excel spreadsheet for statistical analysis using Statistical Packages for Social Sciences (SPSS) (version 27.0; SPSS Inc., Chicago, IL, USA). Numerical variables were summarised as mean and standard deviation, while categorical variables were presented as counts and percentages. A p-value of ≤0.05 was considered statistically significant. Results: The study population consisted of 70% males with a mean age of approximately 55 years. Road traffic accidents were the most common mode of injury. The mean time for radiological union in the nailing group was 14.05 weeks, significantly shorter than the 16 weeks in the plating group. The mean range of knee flexion was 111° in the nailing group and 114.5° in the plating group. The average NEER score was 84.10 for the plating group and 83.30 for the nailing group. There was no statistically significant difference in functional outcomes between the two groups. Conclusion: Both retrograde intramedullary nailing and the use of locking compression plates can be considered as suitable treatment options. Early weight-bearing can be initiated with retrograde nailing. No significant difference was observed in terms of outcome, fracture healing, or NEER score. The time taken for radiological union of fractures using both techniques was comparable. Proper operative planning, execution, and adherence to a strict rehabilitation protocol play crucial roles in the overall patient outcome.

INTRAMEDULLARY NAIL OR LOCKING COMPRESSION PLATE FOR FIXING A FRACTURED DISTAL TIBIA: FINITE ELEMENT ANALYSIS ALONG WITH AN ADAPTATION MODEL

Intramedullary (IM) nailing and plating are two major options for the treatment of distal tibial fractures; each method has its own pros and cons. Bone loss due to IM nailing or plating can be a serious concern, which may lead to the premature failure of the implants. Thus, investigating bone remodeling in response to orthopedic implantation is of paramount importance for the purpose of designing more efficient prostheses. The main goal of this study was to predict the effects of nailing and plating on the bone apparent density distribution in tibia, through use of the finite element method (FEM) along with a bone remodeling model. To this end, three-dimensional geometry of tibia, with properties derived from computer tomography (CT) imaging data, IM nail and locking compression plate (LCP) were created. Then, a bone remodeling model and FEM, with physiological-like loading, were combined and implemented using Python programming language. The results showed that both nailing and plating methods cause a reduction in bone apparent density, but the plate affects just the distal part of the tibia, where the implant is present; whereas the IM nail affects almost the whole tibia. Moreover, in agreement with clinical observations, it was found here that the stress shielding effects of the LCP are less pronounced than that of IM nail, in the long term. Stress analysis revealed that the load, to most extent, transferred to IM nail; whereas it transferred to LCP just in the distal part of tibia. On the basis of the results of this work, it might be concluded that plating is a better choice than nailing for distal tibial fracture, from the bone remodeling point of view.

A prospective observational study examining the radiological and functional results of locking compression plate treatment for femur diaphyseal fractures in children

A prospective observational study examining the radiological and functional results of locking compression plate treatment for femur diaphyseal fractures in children

Anterolateral Dual Plate Fixation for Distal Metaphyseal-Diaphyseal Junction Fractures of the Humerus: Biomechanical Finite Element Analysis with Clinical Results.

Distal metaphyseal-diaphyseal junction fractures of the humerus are a subset of injuries between humeral shaft fractures and distal intra-articular humerus fractures. A lack of space for distal fixation and the unique anatomy of concave curvature create difficulties during operative treatment. The closely lying radial nerve is another major concern. The aim of this study was to determine whether anterolateral dual plate fixation could be effective for a distal junctional fracture of the humerus both biomechanically and clinically. A right humerus 3-dimensional (3D) model was obtained based on plain radiographs and computed tomography data of patients. Two fractures, a spiral type and a spiral wedge type, were constructed. Three-dimensional models of locking compression plates and screws were constructed using materials provided by the manufacturer. The experiment was conducted by using COMSOL Multiphysics, a finite element analysis, solver, and simulation software package. For the clinical study, from July 2008 to March 2021, a total of 72 patients were included. Their medical records were retrospectively reviewed to obtain patient demographics, elbow range of motion, Disabilities of the Arm, Shoulder and Hand (DASH) scores, Mayo Elbow Performance Scores (MEPS), and hand grip strength. No fracture fixation construct completely restored stiffness comparable to the intact model in torsion or compression. Combinations of the 7-hole and 5-hole plates and the 8-hole and 6-hole plates showed superior structural stiffness and stress than those with single lateral plates. At least 3 screws (6 cortices) should be inserted into the lateral plate to reduce the load effectively. For the anterior plate, it was sufficient to purchase only the near cortex. Regarding clinical results of the surgery, the range of motion showed satisfactory results in elbow flexion, elbow extension, and forearm rotation. The average DASH score was 4.3 and the average MEPS was 88.2. Anterolateral dual plate fixation was biomechanically superior to the single-plate method in the finite element analysis of a distal junctional fracture of the humerus model. Anterolateral dual plate fixation was also clinically effective in a large cohort of patients with distal junctional fractures of the humerus.

Percutaneous TENS in Pediatric diaphyseal femoral fractures- Respects biology and ends happily

Femoral shaft fractures are amongst the most common major pediatric injuries treated by orthopaedic surgeons. They represent 1-2% of all fractures in the paediatric population. Paediatric males are affected more commonly than females. [1] There are various methods available for operative stabilization of paediatric femoral shaft fractures, which include external fixation, compression plating and rigid and flexible intramedullary nailing. [2] There is no uniform consensus on the treatment modality for femoral shaft fracture in school-aged children between 6 years to16 years. Titanium elastic nailing system (TENS) is a recent and widely used technique which allows stable reduction, maintenance of reduction and early mobilization. [3] American Academy of Orthopaedic Surgeons (AAOS) recommends with strong evidence based support in favour of the use of flexible intramedullary nailing for treating children age five to eleven years diagnosed with diaphyseal femur fractures. [4, 5] This device exploits a child’s denser bone, rapid healing and ability to remodel during period of bone growth. Here, we establish this axiom by a detailed case presentation, who was successfully treated with flexible intramedullary nailing for diaphyseal fracture of the femur.

Assessment of Functional Outcome of Humeral Diaphyseal Fractures Treated with Dynamic Compression Plate at National Medical College and Teaching Hospital, Birgunj, Nepal

Introduction: Fractures of the humeral shaft account for roughly 3-5% of all fractures and result from direct and indirect trauma. Common mechanism for this fractures include fall on the motor vehicle accidents, fall on out stretched hand and direct loads to the arm. The shaft of humerus fracture is managed largely conservatively, but with the advent of new surgical techniques and implant options, less tolerance for acceptable deformity and functional deficits, more time consuming with conservative management, many surgeon are increasingly likely to consider surgical management. The aim of our study is to assess the functional outcome of dynamic compression plate in shaft of humerus fracture.Materials and Methods: This is a prospective observational study conductedm in department of orthopedic surgery, NMCTH, Birgunj among 45 patients from 17 years and above presenting with shaft of humerus fracture. The fracture was classified according to AO classification. The patients were treated with open reduction and internal fixation with dynamic compression plate and followed up at 2 weeks, 6 weeks, 12 weeks and 24 weeks till the radiological union was achieved. American shoulder and elbow surgeon’s scoring system was used to assess the final outcome of the study.Results: 45 patients meeting inclusion criteria were included in the study, 3 patients lost follow up hence removed from study. Out of 42 patients, mean age of the patient was 31.95 years. Most of them 27(64.3%) were male. Predominant fracture was on left side 73.8% (31 patients). The study finding showed that 31(73.8%) sustained injury due to road traffic accidents. Majority of the fractures 32(76.20%) were in middle 1/3rd. Most of the patient had A3 type of fracture according to AO classification. The mean post-operative immobilization was 15 years. Forty one (97.61%) fracture united with one (2.39%) fracture going into non-union with mean time of 16.04 weeks. Thirty-seven (88.10%) patients has excellent range of motion of elbow and shoulder while 3(7.10%) had good and 2(4.8%) patient had poor functional outcome. The average ASES score obtained at 24 weeks was 47.07.Conclusion: From our study, it is concluded that open reduction and internal fixation with DCP in shaft of humerus fracture provides excellent functional outcome.

Functional Outcome of Locking Compression Plate in Distal Femur Fractures

Introduction: Distal femur fracture is common in young people with high velocity injury. Management of distal femur fractures is a therapeutic challenge in orthopedics practice due to its extensive soft tissue injuries, bone loss, comminution, articular extension, instability.Open reduction with internal fixation replaces previous trend of closed conservative management and external fixation. Distal femoral locking compression plate (DF-LCP) requires both locking and compression screw fixation of the femur shaft. DF-LCP has been rapidly adopted as an alternative to intramedullary nails, blade plates and non-locking condylar screw.Materials and Methods: Prospective interventional study was done in department of orthopedics at National Medical College and Teaching Hospital, Birgunj for one year among 45 patients of age more than 18 years with post traumatic closed or open GA Type I, II distal femur fractures, AO Muller type A and C fractures. Ethical approval was obtained from institutional review committee and proper informed consent was taken. Type of implant used was DF-LCP.NEER’S scoring system was used for functional outcome.Results: Out of 45 patients, 42 patients with distal femur fracture were treated by DF-LCP.Three patients lostduring follow up hence removed from study. Out of 42 patients, mean age of the patients was 36.62 years. Most of them 31, (73.8%) were male. Predominant fracture was on right side 29 (69%).The study finding showed that 30 (71.4%) sustained injury due to road traffic accidents. Most of the patients 18 (42.9%) had type A2 fracture according to AO Muller distal femur fracture classification. Complications like surgical site infection observed in 3 cases. 100% union rate achieved with an average union time of 17.26 weeks. On evaluation according to Neer’s criteria mean score was 82.1 (Range: 48-96). Out of 42 patients 24 (57%) had excellent, 14 (33%) had good, 3 (7.2%) had fair and 1 (2.4%) had poor result.Conclusion: The study concluded DF-LCP is effective treatment for distal femur fracture. It provides stable construct for fracture union with excellent functional outcome.

The Duration of Bone Healing and Nonunion Ratio After Ulnar Shortening Osteotomy Using a 5-Hole Forearm Compression Plate With Transverse Osteotomy.

Ulnar shortening osteotomy using various osteotomy sites, osteotomy methods, and surgical techniques with a variety of implants has been reported, but nonunion rates and the duration of bone healing are not uniform by the authors. The purpose of this study was to investigate the duration of bone healing and nonunion ratio in patients who underwent ulnar shortening osteotomy by a 5-hole nonlocking plate with a simple transverse osteotomy for ulnar impaction syndrome and to determine the correlation between the gap length of the osteotomy site and the duration of bone healing. We assessed patients who underwent ulnar shortening osteotomy for ulnar impaction syndrome using a 5-hole nonlocking plate fixation followed by a simple transverse osteotomy between July 2012 and October 2021. This study was a case series study, and the level of evidence was IV. A total of 80 patients were included. The mean age of the patients was 46.7 years, and 46 patients were men. The average bone union period was 41.8 ± 18.7 weeks. The correlation between the gap length of the osteotomy site and the duration of bone union of the osteotomy site was not significant. The nonunion ratio of our method was 2.5%. The nonunion rate of our ulnar shortening osteotomy with a simple transverse osteotomy and a 5-hole nonlocking plate was comparable to that in previous reports, but our method required slightly longer periods for bone union. There was no correlation between the gap length of the osteotomy and the duration of bone union. Level IV (Case series).

Entropy generation and Cattaneo-Christov heat flux effects on Williamson hybrid nanofluid flow through various radiations and geometries: A comparative study

This entire study aims to prove the impacts of linear radiation, nonlinear thermal radiation, and quadratic radiation entropy generation on Williamson hybrid nanofluids through a comparative analysis of the magnetohydrodynamic flow in a porous material over a stretching cylinder and plate. We used hybrid nanofluid blood based on silver (Ag) and aluminum dioxide () nanoparticles. Using the Runge-Kutta technique of fourth order, the controlling nonlinear coupled Partial Differential Equations (PDE) are converted into nonlinear coupled Ordinary Differential Equations (ODE). Both numerical and homotopy perturbation methods are used to find the best solution for the nonlinear system. The findings are presented in a table and as graphical representations for a variety of parameters, including temperature, Bejan number, streamlines, entropy generation, and three-dimensional graphs of skin friction and Nusselt number. In this model, we compare the three different thermal radiations over the cylinder and plate compression, and those are represented via graphs. The velocity profile decreases for Williamson hybrid nanofluids over both cylinders and plates, while the magnetic field parameters increase. Furthermore, the results demonstrate a high level of agreement with earlier literature when compared. Our model may apply to physiological systems, pharmacological transport phenomena, and medical simulation tools. During endoscopy, a magnetic force field identifies or treats diseases. surgical procedures, nano-pharmacological delivery systems, etc.

Optimal screw configurations of broad and curved broad locking compression plates for femoral shaft fractures

Optimal screw configurations of broad and curved broad locking compression plates for femoral shaft fractures

Potential problem and solution of lateral plate postposition for the posterolateral tibial plateau fracture

BackgroundThere has been controversial for the treatment of the posterolateral tibial plateau fractures (PTPF). This study aimed to evaluate clinic outcomes of the lateral locking compression plate (LCP) postposition, analyze the feasibility of LCP postposition through anatomical measurement, and address the potential problems of LCP postposition through the biomechanical assessment.Methods39 patients with PTPF undergoing LCP fixation between June 2019 and June 2022 were retrospectively evaluated. All cases were divided into two group: Group A (15 cases) employed plate transverse arm postpositioning with posterolateral (PL) fracture fixation using two raft screws, while Group B (24 cases) utilized non-postpositioning with fixation by a single raft screw. Surgical duration, intraoperative blood loss, the change of lateral tibial plateau angle (LTPA), lateral tibial plateau posterior slope angle (LPSA) and fracture collapse between immediate postoperative and last follow up, range of motion (ROM), HSS knee score, and Lysholm knee score were recorded. CT measurements of the fibular head superior space and LCP transverse arm were taken in 50 healthy adult knees to assess postposition feasibility. Finally, three fracture models were established using finite element analysis: Model A with plate postposition and PL split fracture fixed by two raft screws of transverse arm, Model B with plate non-postposition and PL split fracture fixed by one raft screw, and Model C with plate non-postposition and PL split fracture fixed by one raft screw and anterior–posterior tension screws. Loadings of 250N, 500N, and 750N were applied for the analysis of the displacement degree, von Mises stress distribution.ResultsResults indicate comparable operative duration and intraoperative hemorrhage between groups. Complications were minimal in both groups. Group A demonstrated superior outcomes in terms of radiographic parameters, functional scores, and fracture collapse prevention. CT measurements revealed compatibility in 72% of healthy knees with the postpositioning technique. Finite element analysis indicated favorable biomechanical stability.ConclusionNot all patients with PTPF were applicable to the management of the plate postposition and two raft screws fixation, even though this technique exerted good biomechanical stability and achieved satisfactory clinic outcomes. When the PL fracture was fixed by only raft screw through LCP owing to various reasons, two anterior–posterior tension screws might be necessitated to maintain the fracture stability.

The effect of joint inclination angle on mechanical properties of rock mass studied by model test and DEM simulation

The joint inclination angle is a crucial factor influencing the mechanical behavior of rock masses and greatly affects the stability of rock mass engineering. The article utilizes cement mortar to fabricate jointed rock models with mechanical properties that closely resemble those of real rock formations. The compressive plate speed of the loading test machine is 0.005 mm/s, and the axial static loading rate ranges from 0.5 to 1.0 MPa/s. To investigate the influence of joint inclination angles on the macroscopic mechanical properties of the rock, the study initially employs indoor full-field observation and the non-contact technology known as Digital Image Correlation (DIC). Experiments are conducted on rock specimens with varying joint inclination angles of 30°, 45°, 60°and 90°. Following this, numerical simulations employing the Discrete Element Method (DEM) are conducted to analyze the microfracture process. The model test and numerical simulation results demonstrate good agreement, particularly regarding the failure modes. It is found that the most common failure mode for jointed rock is a composite form of shear and tension. As the joint inclination angle increases, tensile failure becomes more prominent. The Young’s modulus EJR/ER and peak strength σJR/σR ratios between jointed and jointless rock vary with the joint inclination angle, exhibiting a "V" shaped curve. A joint inclination angle of 45° results in minimum strength and modulus in the macro mechanical properties. The joint inclination angle has a negligible effect on the rock mass’s residual strength, maintaining an approximately constant ratio of 0.14 between residual and peak strength σr/σp .

Finite element modeling of fracture compression by compression plates.

Dynamic compression plating is a common type of fracture fixation used to compress between bone fragments. The quality of compression across the fracture is important for postoperative stability and primary bone healing. Compression quality may be affected by surgical variations in plate prebend, screw location, screw torque, fracture gap, and implant material. Computational modeling provides a tool for systematically examining these factors, and for visualizing the mechanisms involved. The purpose of this study was to develop a finite element model of dynamic compression plating that includes screw insertion under torque control, establish model credibility through sensitivity analyses and experimental validation, and use the model to examine the effects of surgical variables on fracture compression and postoperative stability. Model-predicted compressive pressures had good agreement with corresponding synthetic bones experiments under a variety of conditions. Models demonstrated that introducing a 1.5or 3 mm plate prebend (using a 4.5 mm narrow LCP plate) eliminated gapping at the far cortex, which is consistent with clinical recommendations. However, models also revealed that plate prebend led to sharp decreases in fracture compressive force, exceeding 80% in some cases. A 1.5 mm plate prebend resulted in the most uniform pressures across the fracture. Testing of a simplified model form used in previous computational modeling studies showed large inaccuracies for constructs with plate prebend. This study provides the first experimentally validated computational models of dynamic compression plate fracture fixation, and reveals important effects of plate prebend and fracture gap on fracture compression quality.