Experimental Study on Rats with Critical-Size Bone Defects Comparing Effects of Autologous Bone Graft, Equine Bone Substitute Bio-Gen® Alone or in Association with Platelet-Rich Fibrin (PRF).

BACKGROUND: A critical-sized bone defect (CsBD) is considered one that will not heal spontaneously and requires reconstruction. This study aims to compare the results of using different bone reconstructive techniques and to study the potential of platelet-rich fibrin (PRF) to enhance the healing properties of a bone substitute (BS). METHODS: In this experimental study on rats, the treatment of critical-sized bone defects was carried out by analysing four groups: a control group in which the bone defect was left empty; a group treated with Bio-Gen®; another group in which the defect was treated with PRF in combination with Bio-Gen®; and the last that was treated with autologous bone graft (ABG). The defects were evaluated by microcomputed tomography (µCT) and then histomorphometrically. RESULTS: From both the histological and imagistic point of view, the best results were registered in the ABG group, followed by the group treated with Bio-Gen® with PRF, Bio-Gen® group, and control group, with statistically significant differences. CONCLUSIONS: A 5 mm defect in the rat radius can be considered critical. ABG showed the best results in treating the bone defect. PRF significantly enhanced the efficacy of Bio-Gen®.

Total Knee Arthroplasty in Patients with Ipsilateral Hip Fusion: Technical Notes and Literature Review.

Numerous studies report the success and outcomes of the total knee arthroplasty (TKA); however, few papers present patients with knee osteoarthritis and ipsilateral hip fusion. One controversy when treating patients requiring a TKA with prior ipsilateral hip fusion is whether to first perform a total hip arthroplasty (THA) of the fused hip, followed by the ipsilateral TKA, or to proceed with the TKA without replacing the hip; studies suggest that the position of the fused hip is a key factor when making this therapeutical decision. In addition, performing a TKA in patients with an ipsilateral fused hip may require modifications to the surgical technique generated by the lack of joint mobility in the hip. We identified 12 studies encompassing 30 patients with hip fusion and ipsilateral TKA in current orthopedic literature, but only six offered insights on patient positioning on the operating table during surgery. This study aims to review the current literature on patients with knee osteoarthritis and prior ipsilateral hip fusion and to present some technical considerations when performing a TKA on a 75-year-old patient with hip ankylosis who underwent a total ipsilateral knee arthroplasty in our clinic.

Peri-implant distal radius fracture due to car collision.

Peri-implant fractures have gained increasing importance in orthopedics as the number of surgical procedures involving orthopedic implants rises globally. These fractures pose a significant challenge in terms of diagnosis, treatment, and postoperative management. They manifest as stress fractures distal to the implant site. Developing an effective treatment strategy involves evaluating multiple influencing factors. This article presents a rare case of a peri-implant distal radius fracture in a 63-year-old man, with no comorbidities, resulting from a car accident, classified as C1U in the Michele D'Arienzo system. The surgical intervention included plate fixation for the radius and wire fixation for the ulna. The wire was used for ulna instead of a plate, due to skin injuries, with good results. As life expectancy rises and individuals remain active in their elder years, the incidence of peri-implant fractures is expected to increase. Factors such as the implant type, surgeon's approach, and patient-specific elements may influence peri-implant fracture occurrence. The widespread use of plate fixation for distal radius fractures may also contribute to a parallel increase in such fractures. Providing detailed context and specific case presentation allows better understanding and implications for clinical practice.

A Retrospective analysis of peri-implant fractures: insights from a large volume clinical Study.

PURPOSE: Peri-implant fractures (PIFs) are a concept in evolution for which different diagnostic criteria have been proposed and modified over time. They have not been extensively reported. PIFs are usually located in the distal part of previous osteosynthesis, where fragile bone is in contact with the rigid implant and are a significant complication after orthopaedic surgery, which requires careful management and treatment. This clinical study presents findings from a retrospective analysis of PIF's, providing description of characteristics and outcomes. They provide information about the associated risk factors and description of the effectiveness of various treatments. MATERIALS AND METHODS: A retrospective analysis was performed in a clinical study involving patients with PIFs. Data from medical records, radiographic images, and surgical reports were collected and analyzed. The study included patients with refracture of pre-existing osteosynthesis admitted to the hospital between 2015 and 2022. Demographic information, fracture characteristics, surgical interventions, and post-operative outcomes were assessed. Each case was followed for a minimum of one year after surgery, and a critical analysis was performed by senior surgeons. Furthermore, the PIFs were classified according to the type of initial implant and the position of the new fracture in relation to the original implant. RESULTS: Between 2015 and 2022, out of 18,813 fractures treated at a Level 1 traumatology hospital, a total of 85 patients with PIF's were identified. Fracture characteristics varied, including location, fracture pattern, and implant type. Most of the PIFs, 71 cases (83.53%), occurred in the femur. Additionally, there were seven cases (8.24%) involving the humerus, four cases (4.71%) affecting the tibia/fibula, two cases (2.35%) in the radius, and one case (1.18%) involving the clavicle. Surgical management was the primary attitude in treatment. Various techniques were used, including the use of longer and stronger implants to achieve high-quality fixation, facilitating early rehabilitation and return to previous activities. Postoperative complications after surgery for PIFs were observed in 16 cases (18.8%). CONCLUSIONS: Peri-implant fractures (PIF) are a distinct topic and a challenging condition with a high rate of postoperative complications. Complications after the second surgery may be severe and life threatening in older patients. A classification can be useful to make decisions about the optimal treatment in different anatomic areas and type of implant used for primary osteosynthesis. Currently there are no standardized protocols for management, therefore each case should be carefully discussed and planned before surgery.

Updates on Biomaterials Used in Total Hip Arthroplasty (THA).

One of the most popular and effective orthopedic surgical interventions for treating a variety of hip diseases is total hip arthroplasty. Despite being a radical procedure that involves replacing bone and cartilaginous surfaces with biomaterials, it produces excellent outcomes that significantly increase the patient's quality of life. Patient factors and surgical technique, as well as biomaterials, play a role in prosthetic survival, with aseptic loosening (one of the most common causes of total hip arthroplasty failure) being linked to the quality of biomaterials utilized. Over the years, various biomaterials have been developed to limit the amount of wear particles generated over time by friction between the prosthetic head (metal alloys or ceramic) and the insert fixed in the acetabular component (polyethylene or ceramic). An ideal biomaterial must be biocompatible, have a low coefficient of friction, be corrosion resistant, and have great mechanical power. Comprehensive knowledge regarding what causes hip arthroplasty failure, as well as improvements in biomaterial quality and surgical technique, will influence the survivability of the prosthetic implant. The purpose of this article was to assess the benefits and drawbacks of various biomaterial and friction couples used in total hip arthroplasties by reviewing the scientific literature published over the last 10 years.

Biomechanical Comparison of Conventional Plate and the C-Nail® System for the Treatment of Displaced Intra-Articular Calcaneal Fractures: A Finite Element Analysis.

The C-Nail® system is a novel intramedullary fixation method for displaced intra-articular calcaneal fractures. The aim of this study was to evaluate the biomechanical performance of the C-Nail® system and compare it with conventional plate fixation for the treatment of displaced intra-articular calcaneal fractures using finite element analysis. The geometry of a Sanders type-IIB fracture was constructed using the computer-aided design software Ansys SpaceClaim. The C-Nail® system (Medin, Nové Mesto n. Morave, Czech Republic) and the calcaneal locking plate (Auxein Inc., 35 Doral, Florida) and screws were designed according to the manufacturer specifications. Vertical loading of 350 N and 700 N were applied to the subtalar joint surfaces to simulate partial weight bearing and full weight bearing. Construct stiffness, total deformation, and von Mises stress were assessed. The maximum stress on the C-Nail® system was lower compared with the plate (110 MPa vs. 360 MPa). At the bone level the stress was found to have higher values in the case of the plate compared to the C-Nail® system. The study suggests that the C-Nail® system can provide sufficient stability, making it a viable option for the treatment of displaced intra-articular calcaneal fractures.

Treatment of Knee Osteochondral Fractures.

Osteochondral lesions (OCLs) that are frequently encountered in skeletally immature and adult patients are more common than once thought, and their incidence rate is rising. These lesions can appear in many synovial joints of the body, such as the shoulder, elbow, hip, and ankle, occurring most often in the knee. The term osteochondral lesion includes a vast spectrum of pathologies such as osteochondritis dissecans, osteochondral defects, osteochondral fractures, and osteonecrosis of the subchondral bone. When considering this, the term osteochondral fracture is preserved only for an osteochondral defect that combines disruption of the articular cartilage and subchondral bone. These fractures commonly occur after sports practice and are associated with acute lateral patellar dislocations. Many of these lesions are initially diagnosed by plain radiographs; however, a computed tomography (CT) scan or magnetic resonance imaging (MRI) can add significant value to the diagnosis and treatment. Treatment methods may vary depending on the location and size of the fracture, fragment instability, and skeletal maturity. The paper reports a 14-year-old boy case with an osteochondral fracture due to sports trauma. The medical approach involved an arthrotomy of the knee, drainage of the hematoma, two Kirschner wires (K-wires) for temporary fixation to restructure anatomic alignment, and a titanium Herbert screw fixing the fracture permanently. The patient had a favorable postoperative outcome with no residual pain, adequate knee stability, and a normal range of motion. The mobility of the knee was fully recovered.

Bone Cements Used for Hip Prosthesis Fixation: The Influence of the Handling Procedures on Functional Properties Observed during In Vitro Study.

The failure of hip prostheses is a problem that requires further investigation and analysis. Although total hip replacement is an extremely successful operation, the number of revision surgeries needed after this procedure is expected to continue to increase due to issues with both bone cement types and cementation techniques (depending on the producer). To conduct a comparative analysis, as a surgeon prepared the bone cement and introduced it in the body, this study's team of researchers prepared three types of commercial bone cements with the samples mixed and placed them in specimens, following the timeline of the surgery. In order to evaluate the factors that influenced the chemical composition and structure of each bone cement sample under specific intraoperative conditions, analyses of the handling properties, mechanical properties, structure, and composition were carried out. The results show that poor handling can impede prosthesis-cement interface efficacy over time. Therefore, it is recommended that manual mixing be avoided as much as possible, as the manual preparation of the cement can sometimes lead to structural unevenness.

Electrochemical and In Vitro Biological Evaluation of Bio-Active Coatings Deposited by Magnetron Sputtering onto Biocompatible Mg-0.8Ca Alloy.

The use of resorbable magnesium alloys in the design of implants represents a new direction in the healthcare domain. Two main research avenues are currently explored for developing or improving metallic biomaterials: (i) increase of their corrosion resistance by designed compositional and structural modifications, and (ii) functionalization of their surfaces by coating with ceramic or polymeric layers. The main objective of this work was to comparatively assess bio-functional coatings (i.e., highly-crystallized hydroxyapatite and silica-rich glass) deposited by radio-frequency magnetron sputtering (RF-MS) on a biodegradable Mg-0.8Ca alloy (0.8 wt.% of Ca). After probing their morphology (by scanning electron microscopy) and structure (by Fourier transform infrared spectroscopy and grazing incidence X-ray diffraction), the corrosion resistance of the RF-MS coated Mg-0.8Ca substrates was electrochemically tested (in synthetic biological media with different degrees of biomimicry), and their cytocompatibility was assessed in osteoblast and fibroblast cell cultures. By collective assessment, the most promising performances, in terms of mass loss (~7% after 12 days), hydrogen release rate (~6 mL/cm2 after 12 days), electrochemical corrosion parameters and cytocompatibility, were obtained for the crystalline HA coating.

Treatment of C1.1 (AO-41) tibial plateau fracture: A finite element analysis of single medial, lateral and dual plating.

Bicondylar tibial plateau fractures pose many challenges in surgical treatment. The aim of the present study was to analyze three methods of reduction, single medial, single lateral, and dual plating, for the treatment of a bicondylar tibial plateau fracture, through finite element analysis (FEA). A simple metaphyseal fracture, type C1.1 (AO-41) was modeled on a CT-derived 3D model of the knee. Lateral and medial proximal tibial polyaxial plates with screws were modeled and placed accordingly for the three methods of reduction. Simulation of physiological type loading corresponding to the maximal weight acceptance phase during a slow walking gait cycle was performed using FEA. Values of stress and strain were recorded near the fracture lines. Dual plating provided a decrease of stress and strain in the tibial plateau area. However, the differences in the values among the three cases were small. The stress concentration areas were located in the vicinity of the fracture, predominantly in the area of the tibial plateau. Considering the limitations of the present study, the results revealed that dual plating leads to smaller stress and strain values near the fracture lines in the tibial plateau area. However, values obtained for single lateral plating are close in range. Considering the complexity of the surgical approach for dual plating, single lateral plating may be a solution for good reduction with fewer surgical risks and complications. Further studies on the C1.1 fracture (AO-41) are needed to analyze the complex issue of reducing and stabilizing such a fracture and to characterize the postoperative state while providing predictable parameters for an optimal result.

An original method of simulating the articular cartilage in the context of in vitro biomechanical studies investigating the proximal femur.

Biomechanical testing is a necessity given the development of novel implants used in the osteosynthesis of hip fractures. The purpose of biomechanical testing is to recreate realistic conditions similar to the in vivo conditions. Although biomechanical testing of hip arthroplasty has been standardized since the 1970s, there is no consensus at present on testing methodology for osteosynthesis of hip fractures. Most biomechanical studies examining the fractures of the proximal femur in order to optimize implants opt for loading the bone-implant ensemble directly on the femoral head or using a metallic loading part. This loading technique fails to perform a mechanical stress distribution similar to in vivo conditions, which could alter the outcome. The present study aimed to design loading/unloading cups with mechanical properties that resemble those of the cartilage at the hip level. Through the impression and scanning of the cast models obtained, a digital 3D model was created in STL format and this was processed in order to obtain the computer numerical control (CNC) trajectories of the printing head. For prototyping using additive manufacturing technology, a thermoplastic polymer with biochemical properties, such as tensile strength, that resemble those of the adult hip and a Stratasys FORTUS 250 mc CNC machine were used. Loading/unloading cups with similar anatomy and biomechanical forces compared with those of the adult hip were created, which allowed the experimental simulation of the conditions during walking.

Thromboembolic Disease in Haemophilic Patients Undergoing Major Orthopaedic Surgery: Is Thromboprophylaxis Mandatory?

Haemophilia is a rare genetic disorder, that results from various degrees of deficiency of coagulation factor VIII (haemophilia A), or factor IX (haemophilia B), with an X-linked transmission. The patients affected are in the majority of cases males (who inherit the affected X-chromosome from the maternal side), with rare cases of females with haemophilia (FVIII or FIX < 40 IU/dL), situations in which both X-chromosomes are affected, or one is affected, and the other one is inactive (known as carrier). The hypocoagulable state due to the deficiency of clotting factors, manifests as an excessive, recurrent tendency to bleeding, which positively correlates with plasmatic levels. Severe haemophilia results in hemarthrosis, although recent data have shown that moderate or even mild disease can lead to joint bleeding. Recurrent episodes of haemorrhages, usually affecting large joints such as knees, elbows, or ankles, lead to joint remodelling and subsequent haemophilic arthropathy, which may require arthroplasty as a last therapeutic option. Orthopaedic patients have the highest risk among all for deep vein thrombosis (DVT) and venous thromboembolism (VTE) with morbid and potentially fatal consequences. While for the rest of the population thromboprophylaxis in orthopaedic surgery is efficient, relatively safe, and widely used, for patients with haemophilia who are considered to have a low thromboembolic risk, there is great controversy. The great heterogeneity of this particular population, and the lack of clinical trials, with only case reports or observational studies, makes thromboprophylaxis in major orthopaedic surgery a tool to be used by every clinician based on experience and case particularities. This review aims to briefly summarise the latest clinical data and to offer an insight into the current recommendations that readers would find useful in daily practice.