Since the introduction of the first proximal interphalangeal joint (PIP J) arthroplasty by Brannon and Klein fifty years ago, there has been continuous advancement in implant design and surgical techniques, resulting in an expansion of indications. In addition to primary PIP J osteoarthritis, posttraumatic and inflammatory conditions are increasingly being treated. Besides silicon implants, modern surface replacements have become increasingly popular. This article provides an overview of the history and the current state of PIP J arthroplasty and reviews the outcomes of currently available implants. The various implants are compared regarding their clinical function, revision rates, and economic considerations. Technical aspects, including surgical approach selection and postoperative management, are discussed. Possible complications affecting both range of motion and pain perception are addressed separately, and therapeutic solutions are introduced.

We present six cases of post-traumatic osteoarthritis of proximal interphalangeal joint with swan neck deformity and ulnar deviation treated by surface replacement arthroplasty and soft tissue reconstruction using the radial slip of flexor digitorum superficialis tendon.

Traditional Japanese tatami, 6x3 feet rectangular mats featuring a compressed rice straw core covered with woven rush, have been highly regarded by European visitors from the 16th to the 20th centuries for their beauty and cleanliness. Initially, many Europeans found sitting or sleeping on tatami mats uncomfortable. However, owing to its biodegradable and vegan materials, an increasing number now choose tatami for practical reasons such as health benefits, space-saving in densely populated cities, and sustainability. A survey conducted with over 900 non-Japanese individuals (439 in 2020 and 463 in 2023), and interviews with users and vendors in cities like Barcelona (2022) and Torino, Rome, Bologna, and Paris (2023), revealed that European tatami buyers and sellers highly value natural and organic materials. They appreciate the scent, texture, and sustainability. Authentic natural tatami can last for centuries with proper surface replacement – a maintenance practice unfamiliar to many European users and vendors. There is a growing international demand for high-quality, made-in-Japan tatami; however, the supply is currently inadequate. Tatami rooms have become less common in modern Japanese homes, and the number of material producers has drastically decreased from over 10,000 in 1972 to only 260 by 2025. Consequently, most tatami sold in Europe is manufactured in China, but this supply may soon diminish due to high labour costs and low profitability. Without intervention, tatami could disappear from the market. In Japan, domestic demand for tatami has declined since the 1970s, coinciding with the rise of concrete housing. Despite its proven antibacterial and insect-repelling properties, misinformation regarding mould and pests has contributed to this decline. The shift towards artificial tatami-like mats is also notable: currently, only 10% of Japanese tatami uses traditional rice straw and Japanese rush; the majority is made from polystyrene foam, synthetic rush made from plastic or coated paper, or Chinese rush. There is potential for international trade to help bridge this supply-demand gap. Educating users on the practical value of traditional materials and craftsmanship is also imperative.

Abstract This paper investigates the use of the Particle Swarm Optimization (PSO) method to calibrate a finite element model (FEM) using experimental tests. The PSO method, a numerical technique that uses a particle swarm, is used to find the optimal solution by evaluating the position of each particle based on its objective function. The objective function in this study focuses on comparing the calculated and measured natural frequencies. The study uses a sophisticated FEM of a cable-stayed bridge with a main span of about 300 m in Bratislava; the bridge was reconstructed in 2017and included a change in the weight of some parts and replacement of the road surface. The weight of any water pipes and the surface treatment of the pavements are taken into account as additional MATLAB parameters in the calibration process. Through an optimization process using the PSO method, these parameters are fine-tuned to achieve a closer match between the natural frequencies obtained from the measurements and the calculations from the FE model. The results of this study demonstrate the effectiveness of the PSO method in improving the fit by tuning these parameters.

Rationale:Surgical treatment of osteochondral lesions of the talar dome (OLTD), for lesions larger than 15 mm2, surgical treatment remains challenging. To solve these problems, we presented a 3D-printed partial talar surface replacement (PTSR) technique for treating OLTD with severe lesions.Patient concerns:A 23-year-old male patient with OLTD experienced persistent pain for more than a year (Berndt and Harty classification V). Due to the pain, the patient was not allowed to walk long distances or engage in any physical activities.Diagnoses:Preoperative clinical examination and imaging (computed tomography and magnetic resonance imaging) confirmed the diagnosis of OLTD and Berndt and Harty classification V.Interventions:The patient underwent a 3D-printed PTSR surgical procedure.Outcomes:Follow-up at 2 years after surgery showed good ankle function, with no pain or complications. The Visual Analog Scale score decreased from 5 to 1. The American Orthopedic Foot & Ankle Society scores improved from 65 to 90.Lessons:3D-printed PTSR is a new surgical method for OLTD with a larger damage area that can provide satisfactory outcomes. Definitive and convincing conclusions are difficult to draw owing to the limited number of cases in this study. Another limitation is the follow-up period, which was 2 years. In addition, medium- and long-term follow-up is required. For this patient, we planned an annual follow-up, which included physical evaluation and radiography. In the future, a prospective randomized controlled study should be conducted to manage the clinical surgical treatment of OLTDs, including metal partial replacements.

The CCJR® Charles A. Engh, Sr, MD. Excellence in Hip Research Award: Pelvic Tilt and Cup Position Change Significantly in Most Young Patients 10 Years after Hip Arthroplasty.

Abstract The topological and geometric information in B-rep models is essential for various applications, including feature recognition, design verification, and automatic tool path generation. In particular, representing surfaces using an analytic format offers advantages for utilizing geometric information such as surface type, axis of rotation, and radius. Models composed solely of NURBS surfaces often have limitations in extracting this type of information. To address this issue, this study proposes a method for identifying and replacing NURBS surfaces that can be represented analytically. In the first step, the feasibility of substituting a NURBS surface with an analytic surface is determined by examining the characteristics of its isocurves. In the second step, an equivalent analytic surface is created and used to replace the existing NURBS surface. To validate the proposed method, surface replacement experiments were conducted on multiple test cases. The results showed that, among 10 176 NURBS surfaces identified for possible analytic replacement across 37 B-rep models, 9 163 surfaces were successfully substituted in a stable manner. In addition, an experiment comparing feature recognition in the pre- and post-replacement models was conducted. As a result, none of the 12 design features were recognized in the pre-replacement model, whereas all were correctly detected afterward, confirming that the replacement process significantly enhances feature recognition accuracy.

This research aimed to quantitatively investigate the impact of a novel approach, known as the undulatory form inspired by the flower of life concept, on the performance of conventional Savonius Wind Turbine (SWT). This approach entails the replacement of the conventional SWT's concave surface with a series of small blades, distributed in both convex and concave positions, arranged in an undulating pattern along the surface. Four models have been tested (MODEL22, MODEL30, MODEL60 and MODEL80) in an attempt to verify the effectiveness of this new method in enhancing wind turbine power coefficient. We use ANSYS Fluent software to solve the Unsteady Reynolds-Averaged Navier-Stokes (URANS) and the SST k-omega turbulence model equations. The experimental and numerical data supported the innovative methodology, which was meant to show how it could increase the wind turbine's power coefficient in a tip speed ratio (TSR) range of 0.5 to 1.2 while keeping a 15% overlap ratio (OR) relative to the rotor diameter and an inlet velocity of 7 m/s with a R_e=4.43×〖10〗^5. We conducted a comparison between our innovative model and the experimental and numerical studies and found that the undulatory shape significantly improved the power coefficient. MODEL60 was the optimal model, showing an improvement of 17.34% at TSR = 0.7 compared to a wavy-form numerical study and 6.25% at TSR = 1 compared to the experimental study.

Surface replacing proximal interphalangeal joint arthroplasty in patients with post-traumatic versus primary osteoarthritis.

The purpose of this study was to analyze 1 year of data from ongoing assessments of support surface integrity in the acute care (ie, hospital) setting, to formulate recommendations for routine support surface assessment and replacement consideration. Descriptive study. Data were collected from 85 acute care facilities located in urban, suburban, and rural locations across the United States. Facilities were either current or prospective customers of Medline Industries, LP from who voluntarily agreed to participate in a surface assessment program. Data were collected from January through December 2019. Two trained individuals conducted each support surface inspection beginning with a visual inspection of the covering and zipper. Heavy staining or visible prompted an internal inspection of the surface. Finally, a compression test was conducted after which the surface was given a score of its integrity. Evaluations of 5121 surfaces across 85 acute health facilities showed that 59% (n=3021) required immediate replacement, and slightly less than one-third of support surfaces were deemed in good condition. The most common failure modes were holes, tears, and thinning. Staining appears to be a leading indicator for mattress failure. Support surfaces commonly have warrantees of 10years for manufacturing defects, but this should not be interpreted as the expected years of use. Health care institutions should implement regular inspection practices to identify damaged support surfaces and report them to the appropriate department for replacement. Contaminated surfaces pose an infection control risk, and failure of the physical properties of the support surface may impact pressure redistribution capabilities of the surface.

Proximal interphalangeal joint arthroplasty using self-locking type surface replacement implant for symptomatic osteoarthritis: Extended dorsal central splitting approach and intermediate-term outcome.

BackgroundTotal knee arthroplasty (TKA) is one of the most common orthopaedic procedures and the number of patients which undergo TKA will continue to rise in the coming years. Consecutively, the number of necessary revision surgeries will increase. One of the main reasons for revision surgery is aseptic loosening because of a so-called stress-shielding effect. Typically, revision of a primary TKA is done from a bicondylar surface replacement to a stem-anchored prosthesis, which, due to higher stress-shielding, have a shorter survival time than non-stem-anchored systems. Similar to endoprosthetic treatment in pediatric tumor orthopedics, non-ingrown cementless stems can be used. The study aim was to investigate whether this concept can also be applied to reduce stress-shielding in the tibial metaphysis after revision TKA in adults.MethodsSix tibial biomechanical bone with stemmed tibial TKA components were implanted using surface cementing and a floating-embedded stem or classic full cementing. After implantation, axial force was applied in such a way that the same load was generated as during walking. Two high-resolution cameras and illumination spots were used to record changes on the bone surface circumferentially in three regions of interest and from three different views.ResultsWith regard to the fixation method, a significant difference could be demonstrated in the metaphyseal and in the middle region around the stem (p < 0.001). At the tip of the stems, the reduction of strain energy density showed a stress shielding reduction for the floating-stemmed models in two of three views (ventromedial p = 0.002, lateral p = 0.398, and dorsal: p = 0.027).ConclusionsIn revision surgery after TKA, the use of floating-embedded, uncemented stems without bony ingrowth shows significant reduction of metaphyseal stress-shielding within the proximal tibia. This technique could be a viable alternative to prevent early aseptic loosening and should be examined in future in-vivo studies.

The replacement of greenhouse surfaces with photovoltaic cells currently presents issues with internal shading and uneven illumination, which adversely affect crop growth and yield. Therefore, in order to improve greenhouse lighting by altering the arrangement of photovoltaic cells for greater economic and environmental benefits, four cities (Harbin, Shenyang, Nanjing, and Guangzhou) were selected for this study. Greenhouse models were established using the DesignBuilder software tool, focusing on the summer and winter growth stages of cherry tomatoes and strawberries. Two arrangements were employed—compact (CR) and checkerboard (BR)—to evaluate 18 scenarios based on power generation, illuminance uniformity, and temperature. Analysis revealed that, among the four cities, the checkerboard arrangement improved average illumination uniformity by 37.34%, 37.9%, 38.2%, and 35.8%, respectively, compared with the compact arrangement. Except for nine rows of photovoltaic cells in Guangzhou, the unit of area power generation of the schemes exceeded 80 kWh/m2 in summer, with excellent power generation efficiency. In winter, there was a relative decrease. Among the four cities, only Harbin reached seven rows of photovoltaic cells which produced more than 80 kWh/m2 under the unit of area of photovoltaic cells, while the other three cities achieved five rows. Strawberries are not suitable for growing in Harbin and Shenyang in winter. In addition to this, cherry tomatoes and strawberries in different regions and at different stages have the best arrangements for growth and for maximizing cost efficiency.

We compared the 2 year outcomes after proximal interphalangeal joint surface replacement in 68 joints with severe (>15°) preoperative longitudinal axis deviation and 50 joints without (<5°) preoperative deviation. Patients in both groups had a mean preoperative brief Michigan Hand Outcomes Questionnaire score of 47 and had similar 2 year scores of 72 (95% CI 68-77) (severe deviation) and 70 (95% CI 65-76) (no deviation). Pain, proximal interphalangeal joint range of motion, grip strength and complications did not differ between the groups at 2 years. Ninety per cent of the severely deviated joints had a deviation of less than 15° at follow-up. The revision rates were 5.9% and 1.8% for deviated and non-deviated joints, respectively. We recommend a surface replacing implant to correct severe preoperative axis deviations of the proximal interphalangeal joint, but the risk of revision surgery needs to be considered.Level of evidence: IV.

Isolated Osteochondral defect of the first metatarsal head: A review of surgical treatment options & case report

Impermeable paving surfaces constitute one of the main causes of the aggravation of the urban heat island phenomenon. The replacement of such surfaces with cool pavements represents an innovative and promising approach to mitigate this phenomenon. In this study, the investigated cool pavements allow to restrict the rise in the surface temperature by facilitating the evaporation of water through capillary pores. This process occurs from the water-supplied base to the surface exposed to solar radiation. The pavement's cooling potential is quantified by its surface temperature, influenced by various factors, including prevailing weather conditions, thermophysical properties of the pavement, and its initial temperature and saturation state. Within the scope of this research, the pavement’s qualification for its cooling potential is carried out based on the results of an experimental thermophysical characterization. The main objective is to identify the thermophysical properties governing the surface temperature of the pavement under external climatic conditions.To achieve this objective, 21 cement concrete pavements with different formulations are initially identified. These pavements are categorized into two series: the first (denoted as BS) comprises 8 pavements made from recycled sand and containing hydrophilic materials, while the second (denoted as BI) includes 13 pavements made from structural insulating concrete. The methods employed for pavement characterization are outlined, and the corresponding results, encompassing thermophysical properties measurements and surface temperature values, are presented. Analysis of these results reveals new correlations between thermophysical properties and surface temperature. These correlations highlight the coupling between pavement properties, that dictate surface temperature under real summer conditions, contingent on whether the pavement is draining or non-draining. Furthermore, a robust negative linear correlation (R2= 0.92) is identified between surface temperature and evaporation rate under controlled conditions. This underscores the pivotal role of evaporation in substantially regulating the surface temperature of both types of pavements.

Although the most common procedure for breast reconstruction in Argentina is tissue expansion and implant devices, autologous tissue is frequently utilized. Deep inferior epigastric artery perforator flap (DIEP) is the gold standard for autologous breast reconstruction and, whenever possible, it is the first option. However, there are clinical or other circumstances, when a local or vicinity flaps for autologous reconstruction is preferred, even if exists a surgical and hospital facility for doing microsurgical procedures. The purpose of this manuscript is to describe our experience with the use of local and vicinity flaps for volume and surface replacement in different requirements-autologous breast reconstructions post oncologic resections, volume replacement in weight loss patients and implant-explantation cases. We have utilized the modification of latissimus dorsi musculocutaneous flap (LD) described by Hammond with excellent results and high patient satisfaction. Thoraco-dorsal artery perforator flap is indicated on skin sparing mastectomies (SSMs), immediate reconstruction of the nipple areolar complex and simultaneous coverage of an implant or tissue expander, in irradiated or to be irradiated patients. Lateral intercostal artery perforator (LICAP) flap has gained popularity because the unique position of the perforator at the lower lateral corner of the breast. It allows harvesting immediate vicinity tissue and easy rotation to the breast mound. We have used a modification towards the lateral thoracic wall of the anterior intercostal artery perforator flap for volume reconstruction after implant explantation.in patients who required volume preservation. Medial intercostal artery perforator flap is advantageous whenever the sub-mammary tissue can be used deepithelialized for volume reconstruction with a medial base. The same submammary area harvested as a medially based flap can be irrigated by the LICAP as a reverse LICAP flap that might be designed toward any direction from the piercing point of its perforator. The rest of the donor areas described for breast autologous reconstruction are rarely reported. When surgical facilities and adequate surgical teams are available, the lower abdominal wall is the main donor area, and DIEP, the most common technique utilized.

Purpose. The aim of this study is to construct a typical ore model for Pb-Zn ore range in Ban Lin – Phia Dam and to compare it with the existing ones. The model is constructed based on three main elements of the mineral generation process, such as formation environment, generated-ore fluid source, and deposited-ore mechanism. The obtained results are aimed at determining and predicting the resource of sedimentary exhalative (SEDEX) Pb-Zn ore deposit in Vietnam. Methods. To comprehend the characteristics of the SEDEX Pb-Zn ore deposits in the Ban Lin – Phia Dam area, we employ a combination of approaches that include mineralography to determine the composition and tectonic structure of rocks and ore, inclusion analysis to determine the temperature and inclusion composition, Pb isotopic analysis and stable S isotopic analysis to explore the environment and sources of ore-forming materials. Findings. The sedimentary exhalative (SEDEX) Pb-Zn ore deposit arises from the dissolution of metal-rich salt deposits due to heating at shallow depths (several kilometers). Subsequently, this fluid migrates through faults and fractures to preferred locations where galena and sphalerite precipitate alongside sedimentary basin deposition. Originality. SEDEX ore deposits have been extensively studied in various regions of the world. Although there are multiple theories regarding their origin, including explosion, biological debris accumulation, and surface replacement, each model has its own distinct advantages and limitations in explaining the genesis and development of SEDEX ore deposits. Practical implications. The acquired findings are intended to identify and predict the resources of sedimentary exhalative Pb-Zn ore deposits in Vietnam.

Non-ionizing radiation is the subject of several applications, such as the microwave oven, which is very popular. Its use is characterized by direct user operation and reduced distances between users and the NIR source. Therefore, the level of human exposure in this scenario deserves attention as it is a potential cause of biological effects. In this sense, this paper presents the measurement of a microwave oven with a high level of NIR (above the limit defined by the standard) before and after two types of suggested repairs: the use of epoxy putty (Repair 1) and the replacement of the external surface of the oven (Repair 2). The definitions of measurement methodology, based on FDA and INMETRO standards, are presented and discussed. Finally, we describe an analysis of the efficiency of these repair methods aiming at the safety operation.

Urban green spaces (UGSs) provide numerous ecosystem services (ESs) that are essential to the well-being of the residents. However, these services are often neglected in regional urban development and spatial planning. This study quantified the ESs of a 10.25 ha UGS at Chungnam National University, Daejeon, Republic of Korea, comprising 27 species with 287 tree individuals, using i-Tree Eco. Key regulating ESs investigated included air pollution removal, carbon storage and sequestration, oxygen production, energy use reduction, avoidance of surface runoff, and replacement and functional values. Results revealed significant annual environmental benefits: 131 kg air pollutants removed (USD 3739.01 or ₩5.16 M), 1.76 Mg carbon sequestered, which is equivalent to 0.18 Mg CO2 ha−1 yr−1 (USD 289.85 or ₩0.40 M), 2.42 Mg oxygen produced, energy savings (including carbon offset) valued at USD 391.29 (₩0.54 M), and 203 m3 reduction in surface runoff (USD 413.09 or ₩0.57 M). The annual total benefits of these urban trees amounted to USD 4833.86 (₩6.67 M), USD 16.83/tree, or USD 0.089/capita. Additionally, these trees had replacement and functional values estimated at USD 311,115.17 (₩429.3 M). The study underscores that species selection and abundance of urban trees are fundamental for maximizing the ES delivery in urban areas, highlighting the role of UGSs in ecological and economical sustainability in cities. These insights are valuable for urban planners and policymakers to optimize benefits of UGSs in cities.