Search Results (280)

Management of septic arthritis of the pubic symphysis (SAS) presents with substantial clinical challenges. Firstly, the SAS is an extremely rare entity. Surgical resection of the symphysis plus targeted antibiotic therapy is a widely adopted treatment course. Some patients suffering from SAS develop posterior pelvic insufficiency fractures because of the weakened anterior pelvic ring or as a result of radiation therapy received during treatment for a malignant disease in the lesser pelvis. The literature demonstrates a lack of standardized strategies for restoring pelvic ring integrity based on pelvic instability and posterior pelvic insufficiency fractures caused by SAS. Background and Objectives: This study aimed to determine whether early, primary stand-alone dorsal fusion can be a viable treatment option in SAS and whether there is a clinical benefit compared with temporary anterior fixation or secondary posterior stabilization after failed anterior fixation. Materials and Methods: We performed a descriptive, retrospective analysis covering an eight-year period (2018–2025) including 21 patients who underwent symphyseal resection for destructive SAS. We evaluated peri- and postsurgical data to describe the different surgical methods and their respective outcomes. Results: Ten patients (10/21, 48%) received posterior stabilization (sacroiliac-joint fusion or spinopelvic stabilization). Seven patients (7/21, 33%) were anteriorly fixated either temporarily with an external fixator or permanently with ventral plate osteosynthesis. Four patients (4/21, 19%) did not receive any pelvic stabilization following symphyseal resection as pelvic integrity was present. Three of them (3/21, 14%) showed spontaneous sacroiliac-joint fusion, while 6/7 (86%) of anteriorly fixed patients presented with debilitating sacral insufficiency fractures, had longer hospital stays and a higher count of readmissions and re-operations. Primary posterior stabilization led to shorter hospital stays, less readmissions, and good clinical outcome. Conclusions: Primary posterior stabilization can be a viable course of treatment of SAS and should be considered especially when spontaneous sacroiliac-joint fusion is not present. We suggest that early stabilization of the posterior pelvic ring could be a sensible course of treatment and may prevent debilitating insufficient fractures. While there are many different surgical options for posterior stabilization available (spinopelvic/lumbosacral stabilization, sacroiliac-joint fusion and others), our preliminary data suggest that primary sacroiliac-joint fusion is a quick, minimally invasive and effective way to establish posterior pelvic stability. Full article

Crassulacean acid metabolism (CAM) is a specialized photosynthetic pathway that enhances water-use efficiency by temporally separating nocturnal CO₂ uptake from daytime decarboxylation and carbon fixation. To uncover the regulatory mechanisms coordinating these temporal dynamics, we generated high-resolution, 48 h time-course transcriptomes for the CAM model Kalanchoe fedtschenkoi under both 12 h/12 h light/dark (LD) cycles and continuous light (LL). A rhythmicity analysis revealed that diel light cues are the dominant driver of transcript oscillations: 16,810 genes (54.3% of annotated genes) exhibited rhythmic expression only under LD, whereas just 399 genes (1.3%) remained rhythmic under LL. A smaller set of 3009 genes (9.7%) oscillated in both conditions, indicating that the intrinsic circadian clock sustains rhythmicity for a limited subset of the transcriptome. A gene co-expression network analysis revealed extensive integration between circadian clock components, core CAM pathway enzymes, and stomatal regulators, defining regulatory modules that coordinate metabolic and physiological timing. Notably, key hub genes associated with post-translational and post-transcriptional regulation, including the E3 ubiquitin ligase HUB2 and several pentatricopeptide repeat (PPR) proteins, act as central nodes in CAM-associated networks. This discovery implicates epigenetic and organellar regulation as previously unrecognized critical tiers of control in CAM. Together, our results support a regulatory model in which CAM rhythmicity is governed by both external light/dark cues and the endogenous circadian clock through multi-level control spanning transcriptional and protein-level regulation. To support community exploration, we also provide an interactive eFP (electronic Fluorescent Pictograph) browser for visualizing time-resolved gene expression profiles. Full article

Background and Objectives: Coracoid process (CP) fractures combined with acromioclavicular (AC) joint dislocation are extremely rare, and evidence guiding optimal surgical management remains limited. This retrospective, single-center case series study evaluated clinical and radiologic outcomes after simultaneous fixation of both lesions using a clavicular hook plate and a coracoid screw. Materials and Methods: We retrospectively reviewed 15 consecutive patients with Ogawa type I CP fractures combined with AC joint dislocation who underwent clavicular hook plate and coracoid screw fixation between March 2019 and May 2024. Clinical outcomes at final follow-up included shoulder range of motion (ROM), visual analog scale (VAS) for pain, and the Constant score. Radiologic outcomes included CP union confirmed by computed tomography (CT) and residual AC joint subluxation. Results: The cohort comprised 13 men and 2 women with a mean age of 55.2 years, and the mean final follow-up was 40.2 months. At final follow-up, mean ROM was 168° for forward elevation, 161° for abduction, and 69° for external rotation at the side, with internal rotation to L1. The mean VAS score was 0.4 and the mean Constant score was 97. CT-confirmed union of the CP fracture was achieved in all patients, and no residual AC joint subluxation was observed. All patients returned to sports and activities of daily living. Conclusions: In this series, simultaneous fixation using a clavicular hook plate and a coracoid screw provided reliable stabilization for CP fractures with AC joint dislocation, achieving consistent CP union, restoration of AC joint alignment, and favorable clinical outcomes. However, given the retrospective, non-comparative study design, these findings should be interpreted with caution, and further comparative studies are warranted. Full article

Background/Objectives: War-related mandibular injuries result in extensive soft-tissue damage, severe comminution, and bone loss, and are associated with high rates of infection and delayed healing. No universally accepted management protocol exists for these injuries. External fixation is commonly used in this context, particularly when internal fixation is unavailable or contraindicated. This study aimed to analyze injury patterns, treatment outcomes, and complications of war-related mandibular fractures treated with external fixation as a primary and definitive stabilization method in a resource-limited setting in eastern Democratic Republic of Congo. Methods: A retrospective review was conducted of all patients who sustained war-related mandibular fractures and were treated with external fixation between January 2017 and December 2024 at the Hôpital Provincial Général de Référence de Bukavu. Demographic data, injury characteristics, treatment details, outcomes, and complications were collected. Factors associated with delayed union and fracture-related infection were evaluated using univariate analysis. Results: Ninety-one patients with severe mandibular war injuries were included. High-velocity gunshot wounds accounted for 94.5% of injuries. Clinical evidence of wound infection at admission was present in 29.7% of patients. The mean delay between injury and external fixation was 9.2 ± 6.6 days. Successful bone healing without secondary bone procedures was achieved in 71 patients (78.0%), with a mean healing time of 7.6 ± 3.0 weeks. Delayed bone grafting was required in 20 patients (22.0%), performed at a mean of 77.3 ± 30.5 days after initial fixation. The overall complication rate was 36.3%, with fracture-site infection being the most frequent complication (30.8%). Bone loss at presentation, clinical infection at admission, and the need for bone grafting were significantly associated with fracture-related infection (p < 0.05). Conclusions: War-related mandibular fractures in this series were characterized by severe comminution, bone loss, infection, and delayed presentation. Despite these challenges, external fixation provided acceptable fracture healing and functional outcomes. Small orthopedic external fixators represent a pragmatic and effective treatment option for complex mandibular war injuries in resource-limited settings. Full article

Osteoarthritis (OA) is a progressive degenerative joint disease that fundamentally alters the mechanical environment of the knee. This study utilizes a finite element framework to evaluate the biomechanical response of the distal femur in healthy and osteoarthritic conditions across critical functional postures. To isolate the bone’s inherent structural stiffness and avoid numerical artifacts, a free-body computational approach was implemented, omitting external surface fixations. The distal femur was modeled as a linearly elastic domain with material properties representing healthy tissue and OA-induced degradation. Simulations were performed under passive gravitational loading at knee flexion angles of $0^{\circ },{60}^{\circ },$ and ${90}^{\circ }$. The results demonstrate that the mechanical response is highly sensitive to postural orientation, with peak von Mises stress consistently occurring at ${60}^{\circ }$ of flexion for both models. Quantitative analysis revealed that the stiffer Normal bone attracted significantly higher internal stress, with a reduction of over 30% in peak stress magnitude observed in the OA model at the most critical flexion angle. Total displacement magnitudes remained relatively stable across conditions, suggesting that OA-induced material softening primarily influences internal stress redistribution rather than global structural sag under passive loads. These findings provide a quantitative index of skeletal vulnerability, supporting the development of patient-specific orthopedic treatments and rehabilitation strategies. Full article

Background: Pin tract infections (PTIs) are a frequent complication of external fixation, yet pediatric trauma-specific data—particularly for open long bone fractures—remain limited and heterogeneous. This study evaluated the frequency, severity, timing, management, and outcomes of PTIs in children and adolescents treated with external fixation for open long bone fractures. Methods: This retrospective single-center study included patients younger than 18 years with open long bone fractures treated with external fixation between 2002 and 2023. PTIs were graded using the Checketts–Otterburn classification (grades I–VI). Management included antibiotic regimen and surgical interventions. Outcome was reported by time to bony consolidation. Results: In 40 patients, 16 patients exhibited PTIs (mild: eight; moderate: five; severe: three. A higher grade of Gustilo–Anderson (p = 0.47) and evident macroscopic contamination (p = 0.73) did not appear to influence the occurrence of PTIs by similar duration of initial antibiotic regimen (p = 0.3). The median time to PTI onset was 49 days (IQR 22–80), with the majority occurring after completion of initial systemic antibiotic therapy. The management of PTIs was predominantly conservative: all eight mild cases resolved with intensified local pin tract care, while all eight moderate and severe cases were treated with systemic antibiotics and five required pin exchange or premature fixator removal. Overall bony consolidation was achieved in all patients, and reoperations were related to trauma severity rather than PTIs except in one patient. No cases of osteomyelitis were observed. Conclusion: Pin tract infections are frequently identified in pediatric open long bone fractures treated with external fixation. Using strict diagnostic criteria, any documented inflammatory change or local secretion at the pin–skin interface is considered indicative of PTI. However, the majority of these infections were classified as superficial and manageable with conservative measures, and all affected fractures healed radiologically. Full article

Objective: Lumbar interbody fusion (LIF) is widely used to treat degenerative spinal disorders; however, both fixation strategies and interbody Cage designs still present biomechanical limitations. This study aimed to develop a posterior lumbar interbody fusion Cage using topology optimization and to compare the biomechanical performance of oblique pedicle screw fixation with conventional fixation. Methods: A validated three-dimensional nonlinear finite element model of the L1–L5 lumbar spine was established based on CT data. A two-step weighted topology optimization was applied to the L3–L4 interbody Cage to determine both the external contour and the internal bone graft window. Finite element models with oblique pedicle screw fixation and conventional pedicle screw–rod fixation were constructed and evaluated under static physiological loads and whole-body vibration conditions. Results: Compared with the conventional Cage, the topology-optimized Cage combined with oblique fixation significantly reduced the maximum von Mises stress on adjacent endplates and decreased Cage displacement under both static and dynamic loading. Although stresses in the Cage and screws increased relative to traditional fixation, all values remained well below material yield limits. Conclusions: The combination of a topology-optimized Cage and oblique pedicle screw fixation improves load transfer and structural stability while reducing the risk of endplate damage and Cage subsidence. This approach provides a promising alternative design strategy for posterior lumbar interbody fusion. Full article

Background/Objectives: The use of temporary pacemakers is increasing every year. Conventional temporary pacemakers are connected to the myocardium via a passive-fixation lead (temporary pacing with passive fixation leads; TPPF), which compromises their effectiveness and safety. Off-label active-fixation systems (temporary pacing with active fixation leads; TPAF) are a safer alternative. The main objective of this study was to assess the clinical and economic impact of TPAF versus TPPF. Methods: We conducted a literature search based on the clinical outcomes of both pacing techniques. We then carried out a descriptive comparative analysis and extrapolated the results to the Spanish, European, and global populations. Results: Of the 1015 articles located, the analysis included five articles from ECTSF and eight from ECTEFA, prospective and focused on the recording of complications. It is estimated that the implementation of ECTEFA as the first option for ECT would lead to a 94.7% reduction in complications. In economic terms, it would mean a 55.72% reduction in the cost of the procedure. Conclusions: TPAF leads to considerable clinical improvement compared with TPPF. Furthermore, while the price of TPAF doubles the procedural cost, the reduced cost of hospital stays and treating complications means the active-fixation systems could substantially reduce the overall cost of temporary pacing for healthcare systems. Full article

Understanding how supplemental nitrogen (N) interacts with biological N₂ fixation (BNF) in modern soybean cultivars is essential for designing fertilization strategies that avoid unnecessary N inputs. We investigated N partitioning among soil, fertilizer and symbiotic sources in soybean grown in a greenhouse pot experiment on a tropical Oxisol. Plants were inoculated with Bradyrhizobium and subjected to four N managements: no external N, soil-applied ¹⁵N-urea (20 kg N ha⁻¹), foliar ¹⁵N-urea (2 kg N ha⁻¹, 0.7% w/v), and the combination of soil + foliar N. Using ¹⁵N isotope dilution, we quantified N derived from the atmosphere (NDFA), fertilizer (NDFF) and soil (NDFS) at organ and whole-plant scales, and related these fractions to nodulation, nitrogenase activity and yield. In the absence of external N, NDFA exceeded 97% in all organs, indicating a strong reliance on BNF and efficient internal N remobilization during grain filling, accompanied by higher leaf nitrate reductase activity. Soil and soil + foliar N markedly increased NDFF and NDFS while suppressing nodulation (particularly at V4) and reducing nitrogenase activity, yet they did not improve grain yield or vegetative biomass. Foliar N alone had only modest effects on N partitioning and did not enhance yield. Under these tropical soil conditions, symbiotic fixation and internal N remobilization were sufficient to meet grain N demand, highlighting the limited agronomic benefit and potential ecological cost of supplemental N during reproductive growth. Full article

External fixation is widely used in trauma care for managing bone and soft tissue injuries. These devices are often associated with psychological challenges and are often not followed up with sufficient psychological support for the patient. The specific psychological impact of external fixation following traumatic injuries remains underexplored. This scoping review aimed to synthesize the current literature on the psychological impact of external fixation in trauma patients. A systematic search of CINAHL, Cochrane Library, PsycInfo, PubMed, Scopus, Google Scholar, and EBSCO identified ten studies (2006–2024), from the USA, Europe, Asia, and Oceania to be included based on inclusion criteria of using the device for traumatic injuries (excluding limb lengthening procedures) and assessing psychological outcomes using validated tools. Data extracted included injury type, fixator application, survey type, and mental health outcomes. Common measures included HADS, SF-36/SF-12, PedsQL, CRIES-13, EQ-5D-5L, and patient-reported questionnaires. The findings showed that elevated psychological distress was greatest during early recovery (~1 month). Body image concerns were frequently reported with the fixator in place; however, partial recovery of mental health scores was seen by 12–24 months. These findings emphasize the need for additional research and a greater integration of mental health resources in trauma care protocols involving external fixation. Full article

The papermaking and recycling industries face increasing demands to improve efficiency, product quality, and environmental performance under conditions of water closure and high furnish variability. This study presents a comprehensive assessment of process control and management strategies for optimizing fines behavior, retention and fixation efficiency, de-inking performance, and ash balance in modern papermaking systems. The surface chemistry of fines was found to play a pivotal role in regulating charge distribution, additive demand, and drainage behavior, acting both as carriers and sinks for dissolved and colloidal substances. Results show that light, targeted refining enhances external fibrillation and produces beneficial fines that strengthen fiber bonding, while excessive refining generates detrimental fines and impairs drainage. Sequential retention programs involving polyamines, polyaluminum compounds, and microparticle systems significantly improve fines capture and drainage stability when operated under controlled pH and ionic strength. In recycling operations, optimized flotation conditions coupled with detackifiers and mineral additives such as talc effectively reduce micro-stickies formation and deposition risks. Ash management strategies based on partial purge and coordinated filler make-up maintain bonding, optical properties, and energy efficiency. Overall, the findings emphasize the need for an integrated wet-end management framework combining chemical, mechanical, and operational controls. Perspectives for future development include the application of biodegradable additives, nanocellulose-based reinforcements, and data-driven optimization tools to achieve sustainable, high-performance paper manufacturing. Full article

Background/Objectives: Open tibial shaft fractures are severe injuries associated with high risks of infection and malunion. Although external fixation is commonly used for provisional stabilization, it provides limited control over alignment and soft tissue handling. This study aimed to evaluate and compare provisional reduction plating with external fixation for the staged management of Gustilo–Anderson type II–III open tibial fractures. Methods: Fifty-nine patients (mean age, 38.5 years) treated with staged debridement and delayed intramedullary nailing (IMN) were retrospectively reviewed. Thirty-two patients underwent reduction plating with external fixation (group A), and 27 underwent external fixation alone (group B). Clinical, radiographic, and functional outcomes, including infection, union, malunion, operative time, and Lower Extremity Functional Scale (LEFS) scores, were analyzed. Results: Deep infection and nonunion rates were comparable between the groups. Group A had fewer malunions (3.1% vs. 18.5%), shorter operative times, and faster progression to union than group B. The LEFS scores were higher in group A, indicating better functional recovery. Conclusions: Provisional reduction plating before IMN appears to enhance alignment, preserve soft tissue integrity, and improve surgical efficiency without increasing the risk of infection or delaying union. These findings suggest that it may be a safe and effective adjunct to the staged treatment of complex Gustilo–Anderson type II–III open tibial fractures. Full article

The primary objective of external fixation is to stabilize bone fractures, with the mechanical characteristics of the fixation system playing a critical role in shaping the biomechanical environment of the fracture and, consequently, the healing process. This study presents an experimental investigation of the stability of eight unilateral external fixation configurations applied to an open tibial fracture. The stiffness of each configuration was evaluated under axial compression, anterior–posterior (AP) bending, medial–lateral (ML) bending, and torsional loading. In addition, the effects of structural parameters—such as the number of half-pins, planarity of the configuration, and interfragmentary distance—on fixator stiffness and generated stresses were examined. The results revealed a linear relationship between applied load and both bone segment displacement and principal stresses. Biomechanical tests demonstrated that biplanar configurations provide sufficient stability for open tibial fractures, while simultaneously offering an optimal structural design for the fixation system. Moreover, the number of half-pins was identified as a statistically significant factor influencing configuration stiffness under axial loading and torsion, with biplanar configurations proving particularly effective in torsional scenarios. However, in AP and ML bending tests, neither configuration type nor any individual parameter produced statistically significant differences in bending stiffness. Interestingly, interfragmentary distance did not exert a statistically significant effect on configuration stiffness under any loading condition. Furthermore, neither configuration type nor the analyzed parameters had a notable influence on the principal stresses measured at the control points. Full article

Background and Objectives: Femoral malunion, defined as healing of a femoral fracture in an anatomically incorrect position, can lead to significant biomechanical and functional impairment despite modern fixation techniques achieving union rates near 99%. The lack of a universal definition and standardized management approach continues to hinder optimal outcomes. This review aims to synthesize the literature on the causes, clinical presentation, radiologic assessment, surgical indications, corrective procedures, and outcomes of femoral malunion to guide clinical decision-making and future research. Materials and Methods: A narrative review of peer-reviewed orthopedic literature was conducted, focusing on adult femoral malunions across anatomical regions. Articles detailing deformity thresholds, imaging modalities, corrective osteotomies, and fixation strategies were included. Particular emphasis was placed on region-specific deformities—femoral head, neck, intertrochanteric, diaphyseal, and distal femur—and their corresponding surgical correction methods, including valgus intertrochanteric osteotomy, clamshell osteotomy, and lengthening with external or magnetic intramedullary devices. Results: Malunion most commonly presents as angular, rotational, or length deformity, with thresholds of >5–10° angulation, >10° rotation, or >1–2 cm shortening being clinically significant. Patients may experience pain, limp, gait asymmetry, and early-onset arthritis. Corrective techniques tailored to the anatomical site yield favorable results: valgus intertrochanteric osteotomy restores leg length and alignment; diaphyseal malunions respond well to single- or multi-plane osteotomies with internal fixation or gradual correction; distal femoral malunions often require multiplanar osteotomy to reestablish the joint line. Most series report high union rates and functional improvement, though complications such as infection and hardware failure may occur. Conclusions: Femoral malunion remains a complex but treatable condition. Successful outcomes rely on accurate deformity characterization, patient-specific surgical planning, and restoration of mechanical alignment. Standardized deformity criteria and long-term functional outcome studies are needed to refine management algorithms and improve patient care. Full article

Background: The management of infections involving the distal tibia and ankle is a significant challenge in orthopedic surgery due to complex anatomy and the high risk of complications. The study aims to present our clinical experience in managing these infections and focusing on surgical strategies, infection control, and functional outcomes over a minimum 24-month follow-up period. Methods: This is an observational, retrospective case series of 17 patients treated for osteoarticular infections of the distal tibia and/or ankle between January 2020 and May 2023, in a second-level referral trauma center. A staged surgical approach was employed, including radical debridement, temporary stabilization with external fixation, and, in most cases, implantation of a cement spacer loaded with antibiotics. Functional outcomes were assessed using scores such as EQ-5D-5L. Results: The cohort was predominantly male (76.5%), with a high prevalence of elevated BMI and comorbidities. Infection onset was most frequently associated with open fractures (64.7%). Staphylococcus aureus was the most common isolated pathogen (41.2%), and infections caused by Gram-negative or multidrug-resistant bacteria were associated with more reoperations. Overall, complications occurred in 10 patients (58.8%), requiring reintervention in 9 patients (52.9%). Limb salvage was achieved in 16 of 17 patients (94.1%). Conclusions: Our study highlights the critical role of a tailored, multidisciplinary approach in managing these complex infections. Meticulous surgical planning and proactive management of complications are essential for optimizing patient outcomes. Full article