Search Results (934)

The progressive decline in immune function during aging, termed immunosenescence, is increasingly recognized as a critical driver of skeletal fragility and impaired bone regeneration. This age-associated phenomenon—driven by thymic involution, inflammaging, and the accumulation of senescent immune cells—disrupts bone homeostasis primarily through the establishment of a pro-inflammatory milieu, wherein senescence-associated secretory phenotype (SASP) factors directly reprogram the function and fate of mesenchymal stem cells, osteoblasts, osteoclasts, and chondrocytes. Clinically, this immune-driven disruption of the bone microenvironment manifests across a spectrum of age-related skeletal disorders—including osteoporosis and osteoarthritis as prototypes of systemic and local bone loss, respectively, as well as delayed fracture healing, intervertebral disc degeneration, and periodontitis as paradigms of impaired regenerative and defensive responses. Despite advances in osteoimmunology revealing bidirectional immune-bone interactions, the mechanistic links between senescent immune cells and bone pathophysiology remain incompletely defined, presenting a significant barrier to therapeutic innovation. Herein, we synthesize current evidence to elucidate how immunosenescence, through the dysfunction of both innate and adaptive immunity, progressively dismantles bone homeostasis. We critically evaluate current challenges in dissecting the relative contributions of immunological memory accumulation versus fundamental aging processes to skeletal decline. We identify key knowledge gaps and propose strategic research directions, including longitudinal human immunophenotyping studies and innovative organoid-immune aging models. Such approaches hold the potential to transform the therapeutic landscape of age-related skeletal diseases by enabling precision interventions that target specific immunosenescence pathways to rejuvenate the aging skeleton. Full article

Purpose: Traditional plaster and fiberglass casts remain widely used for fracture immobilization but are associated with recognized challenges, including skin irritation, hygiene limitations, and distress during cast removal, particularly in pediatric populations. Light-cured polymer immobilization (LCPI) systems have been introduced as an alternative method of fracture support. The primary objective of this study was to describe radiographic healing and alignment outcomes among patients treated with an LCPI system. Secondary objectives were to document skin- and device-related events and to identify any unplanned removals or subsequent re-interventions. Methods: A 6-month retrospective cohort study was conducted involving 108 consecutive patients treated with an LCPI system between January and June 2025 at a single orthopaedic clinic. Clinical and radiographic records were reviewed to extract demographic information, injury characteristics, treatment details, immobilization duration, healing outcomes, alignment status, and recorded adverse events. Outcomes were summarized using descriptive statistics. Results: Immobilization was applied for 104 fractures (96.3%), three sprains (2.8%), and one elbow dislocation (0.9%). The cohort (76 males, 32 females; mean age: 13.4 years; range: 4–53) demonstrated radiographic union or progression toward union among fracture cases with available follow-up imaging. Mean immobilization duration was 29.2 days (SD: 6.2; range: 10–48). Alignment at device removal was documented as anatomic or near-anatomic in 103 of 104 fractures (99.1%) based on treating clinician assessment (99.1%). Device breakage was documented in 12 cases (11.1%), of which 3 required additional immobilization. Two patients (1.9%) experienced mild cutaneous reactions that resolved with conservative management. No severe device-related complications were documented. Conclusions: Healing outcomes and recorded adverse events were consistent with expected clinical patterns for this patient population in this descriptive retrospective cohort of patients treated with an LCPI system. These findings provide descriptive real-world data regarding clinical utilization and short-term outcomes in selected patients. Prospective comparative studies are needed to further define effectiveness, safety, cost considerations, and broader applicability across diverse fracture populations. Full article

Background/Objectives: Strain energy density-based algorithms are widely applied in modelling bone healing, yet their use under patient-specific geometry-based conditions remains underdeveloped. This study proposes a patient-specific geometry-based framework for fracture healing simulation and investigates how different postoperative loading conditions influence the mechanical environment of callus remodeling. Methods: Using postoperative radiographic data of a 63-year-old male patient with a distal diaphyseal tibial fracture and concomitant proximal and distal fibular fractures, a three-dimensional finite element model of the tibia was reconstructed, imported into a multiphysics simulation environment, and coupled with an iterative numerical algorithm. A uniform initial callus density of 750 kg/m³ was assumed as a simplified and homogenized representation of the healing tissue. The effects of different mechanical loading conditions (partial weight-bearing, physiological loading, and supraphysiological loading) on the mechanical response and density evolution of the callus were evaluated. Results: Partial weight-bearing resulted in insufficient mechanical stimulation and progressive density loss within the callus. Physiological loading generated strain energy density levels consistent with known osteogenic ranges and contributed to continuous cortical shell formation and overall density increase. Supraphysiological loading was associated with overload-related resorption and spatial heterogeneity, which may reduce callus stability. Conclusions: The findings suggest that loading magnitude may influence the simulated remodeling response of the callus under the assumptions of the present model. These results indicate that intermediate loading conditions were associated with a more pronounced remodeling response compared to reduced or excessive loading for the investigated case. The comparison with postoperative clinical imaging showed qualitative agreement in the spatial distribution of mineralized and less mineralized regions, supporting the feasibility of the proposed patient-specific geometry-based SED-based framework. Full article

Bone plates are widely used in orthopaedic surgery to stabilise fractured bones and support healing following traumatic injuries or osteotomies. However, conventional metallic bone plates suffer from stress shielding and stiffness mismatch with bone, which can hinder optimal healing. Additive manufacturing enables the incorporation of novel metamaterial architectures into polymer-based implants to enhance mechanical properties. The fatigue behaviour of these implants during the healing period is critical to ensuring their structural integrity and long-term performance. In this study, the compressive fatigue performance of fused deposition modelling (FDM)-printed carbon fibre-reinforced polylactic acid (CF-PLA) bone plates were investigated. Four metamaterial structures—tetrachiral, re-entrant, rotating square, and hexagonal—were evaluated under strain-controlled cyclic loading at 20%, 40%, 60%, and 80% of their respective yield strains. The results showed a strong dependence of fatigue behaviour on lattice geometry. Among the tested configurations, the re-entrant structured bone plate exhibited the best overall fatigue performance, sustaining up to 100,000 cycles at moderate strain levels and showing delayed stiffness degradation under high strain conditions. In contrast, rotating square and hexagonal structures showed early stiffness loss and failure at higher strain levels. These findings highlight the importance of lattice design in fatigue performance, although FDM-induced printing defects significantly influence overall fatigue behaviour. Full article

Micro- and nano-container-based self-healing coatings have emerged as a promising strategy for the long-term conservation of cultural heritage artifacts, including metals, stone, organic matter, and construction materials. These coatings incorporate microcapsules or nanocapsules with tailored shell and core materials, enabling autonomous release of healing agents or corrosion inhibitors in response to damage. For metallic artifacts, benzotriazole@mesoporous silica nanoparticles (BTA@MSN) microcapsules achieve selective pH-responsive release, reaching 77% at pH 9.0 and 42% at pH 5.0, effectively mitigating localized corrosion. Temperature-adaptive poly(methyl methacrylate-co-methacrylic acid) (PMMA-MA)/MgO microcapsules exhibit controlled rupture rates, with a 75% reduction at elevated temperatures, enhancing crack repair efficiency by approximately 5%. Organic artifacts, such as wooden or paper manuscripts, benefit from clove oil nanocapsules, which increase tensile strength by 43.5% and fracture toughness by 101.9%, with only 2.91% weight loss over 7 days compared to 33.1% for unencapsulated oil. Advanced fabrication methods—including microfluidics, Pickering emulsions, and multi-core systems—enable high encapsulation efficiency (up to 73.5%), uniform particle size, and repeatable healing. Multi-stimuli responsiveness (pH, temperature, light, magnetic fields) and biobased, environmentally friendly materials further enhance adaptability and sustainability. In this review, “self-healing” is defined broadly to include both physical crack repair and autonomous restoration of protective functions. Overall, self-healing micro/nanocapsule coatings provide a highly controllable, efficient, and durable solution for active heritage protection, representing a shift from passive to intelligent conservation strategies. Furthermore, a systematic comparison of different capsule systems is provided to clarify their respective advantages and limitations. Overall, hybrid systems exhibit the most balanced performance, while inorganic nanocontainers offer superior stability and controlled release, and polymeric capsules enable rapid healing but limited reusability. Full article

Orthopaedic disorders represent a significant clinical challenge in avian medicine, affecting both pet and wild birds. B-mode ultrasound (US) examination is well established in small-animal and equine medicine; it has seen limited application in avian medicine thus far. This study aimed to assess the diagnostic efficacy of B-mode US in comparison to radiography (RX) for orthopaedic avian disorders. A total of 55 birds from six orders were assessed clinically, radiologically, and sonographically. Statistical analysis was conducted for the overall cohort (n = 55) and for a fracture subgroup (n = 51). Cohen’s kappa was used to examine diagnostic agreement. Sensitivity, specificity, and positive and negative predictive values were also computed. Additionally, Fisher’s exact test was employed to evaluate the representativeness and interpretability of both techniques. In the overall cohort, US demonstrated higher sensitivity (97.6%) and specificity (100%) than RX (sensitivity 70.7%, specificity 85.7%). In the fracture subgroup, US demonstrated superior sensitivity (97.3%) compared with RX (75.7%) while maintaining high specificity (100%). The agreement between imaging findings and the clinical reference standard was substantial to good (κ = 0.64 for the total cohort, p < 0.05; κ = 0.74 for the fracture subgroup, p < 0.05). No significant differences were identified between the two modalities in terms of representability and interpretability. However, these findings should be interpreted with caution, as US examinations were performed following RX assessment on a non-blinded basis, which may have introduced observational bias. Despite these limitations, B-mode US appears to provide valuable additional diagnostic information and may serve as a complementary imaging modality in the evaluation of avian orthopaedic conditions. In particular, it may be useful for assessing shoulder girdle injuries, inflammatory conditions of the shoulder joint, and fractures of the sternum and keel, as well as for monitoring bone healing following surgical or conservative treatment. Full article

Background: Adiponectin (ADPN) is a key adipokine with osteogenic potential, but its clinical translation for bone regeneration is hindered by poor in vivo stability. This study aimed to develop poly lactic-co-glycolic acid (PLGA) microparticles as a stable and biocompatible carrier for sustained ADPN delivery to enhance bone repair. Methods: ADPN-loaded PLGA microparticles (ADPN-MPs) were fabricated via emulsion solvent evaporation. Their physicochemical properties were characterized using scanning electron microscopy (SEM) and circular dichroism (CD) spectroscopy. Loading efficiency and drug loading were quantified. In vitro release kinetics and stability under physiological conditions were assessed. Biocompatibility was evaluated using MC3T3-E1 osteoblasts and BMSCs, and in vivo efficacy was tested in a fracture model via gait analysis. Results: Employing CD to evaluate the secondary structure of ADPN, emulsion solvent evaporation for microparticles preparation, and SEM for morphological analysis, we quantitatively assessed the loading efficiency (69.83 ± 4.24%) and drug loading (0.97 ± 0.06%) of ADPN-MPs. Results indicated that ADPN-MPs maintained significant stability under varied pH and temperature conditions and exhibited a controlled release profile, with an average initial rapid release of 14.25% within 24 h and an average cumulative release of 55.00% by day 28. Furthermore, ADPN-MPs promoted the proliferation of MC3T3-E1 and BMSCs without toxicity, demonstrating excellent biocompatibility. Notably, gait analysis in a fracture model showed improved healing in both ADPN and ADPN-MPs groups compared to controls, with ADPN-MPs demonstrating comparable efficacy to free ADPN, supporting its potential as a stable delivery system for bone regeneration. Conclusions: PLGA microparticles serve as an effective, stable, and biocompatible delivery platform for ADPN, significantly promoting bone regeneration in vitro and in vivo. This delivery system enhances the therapeutic potential of ADPN for clinical bone repair applications. Full article

The development of protective coatings that integrate self-healing and environmental tolerance is vital for extending substrate lifespan. In this study, a multifunctional hydrogel composite coating is developed based on a waterborne polyacrylate dynamic covalent network containing oxime–carbamate bonds. The functional monomer MEOC, which contains an oxime–carbamate dynamic bond, was synthesized and incorporated into the waterborne polyacrylate matrix to form a hydrogel network (OC-PA) with intrinsic self-healing capability. Prussian blue (PB) and nano-SiO₂ were incorporated to form a photothermal functional layer, imparting hydrophobicity and converting light into heat for de-icing, while also activating dynamic bond rearrangement within the substrate. When the MEOC content was 7 wt% and the PB content was 2 wt%, the coating temperature rose to 110 °C within 2 min under 0.6 W/cm² irradiation, and the scratch healed within 5 min. After 1 h of fracture repair, the tensile strength reached 6.68 MPa, with a repair rate as high as 92.91%, and de-icing time was reduced from 343 s to 183 s. The coating achieved a water contact angle >100°. At −20 °C, the icing delay time increased by 215%. The hydrogel coating also exhibited excellent abrasion resistance, chemical stability, UV aging resistance, and anti-fouling properties, offering a durable solution for demanding environments. Full article

Background/Objectives: Proximal phalangeal fractures account for 38% of all phalangeal fractures, with unstable patterns requiring surgical intervention. Various modalities have been explored, including open reduction and internal fixation, percutaneous K-wire fixation, and intramedullary techniques. This study explores the technical nuances, indication, and outcomes of antegrade cannulated compressive screw (CCS) fixation of proximal phalangeal fractures. Methods: This retrospective case series involved 18 closed proximal phalangeal fractures in 16 patients who underwent intramedullary headless screw fixation between January 2018 and December 2023. Records were reviewed for demographics, fracture characteristics, and screw type. With the metacarpophalangeal joint flexed at 60–75°, a 1 cm longitudinal incision was made, the extensor tendon split, and a 0.9 mm guidewire advanced anterogradely along the phalangeal axis under fluoroscopy. A 2.2 mm or 3.0 mm SpeedTip CCS was selected based on phalanx size and advanced until fully buried below the cartilage line. Postoperatively, patients were immobilized in a volar intrinsic-plus splint, transitioned to a gutter splint within five to seven days, and commenced on range of motion (ROM) exercises within one week. Primary outcomes included radiographic union, Total Active Motion (TAM), QuickDASH scores, and postoperative complications. Results: All fractures were healed within acceptable radiological parameters and with no postoperative complications. Mean TAM was measured to be 216.0° (SD 7.7°, range 200–230°) and mean QuickDASH was 10.1 (SD 2.8, range 5–16). Conclusions: Antegrade intramedullary headless screw fixation demonstrates feasibility, short-term safety, and excellent early functional outcomes for carefully selected unstable proximal phalanx fractures, supporting its role as a minimally invasive alternative in appropriately indicated cases. Full article

Background and Objective: This study aimed to evaluate the impact of early functional rehabilitation on clinical outcomes and tuberosity healing in older patients undergoing reverse shoulder arthroplasty for proximal humeral fractures. We hypothesized that early functional rehabilitation would not compromise tuberosity healing and would result in comparable or improved outcomes versus postoperative immobilization. Methods: This retrospective matched-pair analysis included patients aged 70 years or older who underwent reverse shoulder arthroplasty for proximal humeral fractures, with 12 to 24 months of follow-up. Group allocation was time-based: earlier patients received immobilization and later patients underwent early rehabilitation. Matching was based on sex, age, body mass index, fracture classification (Neer), and glenosphere size. Outcomes included patient-reported scores, range of motion, and radiographic assessment of tuberosity healing using standardized imaging. Results: Forty patients (20 per group) with a mean age of 80.7 years and a mean follow-up of 16.1 months were included. The early rehabilitation group demonstrated significantly higher Constant scores (p = 0.044), age- and sex-adjusted Constant scores (p = 0.033), and greater active external rotation (p = 0.002). Anatomical tuberosity healing was seen in 28 of 40 patients (70%). Greater tuberosity healing occurred in 75% and lesser tuberosity healing in 85% of patients with available axial imaging. One deep infection occurred in the early rehabilitation group and was successfully managed. Conclusions: Early functional rehabilitation after reverse shoulder arthroplasty in older adults with proximal humerus fractures improved functional outcomes without compromising tuberosity healing. Full article

Bone tissue plays a vital role in the human body and possesses intrinsic self-repair mechanisms; however, large defects or pathological fractures may exceed its natural healing capacity. Bone tissue engineering provides promising strategies to restore bone integrity through the use of scaffolds, growth factors, and stem cells. While calcium phosphate (CaP)-based ceramics, such as hydroxyapatite (HAp) and tricalcium phosphate (TCP), represent the current benchmark, their limitations, including slow degradation (HAp) and limited osteoinductivity (TCP), have driven the development of alternative biomaterials. In this context, magnesium phosphate (MgP)-based materials have gained increasing attention due to their tunable resorption rate, improved biodegradability, and ability to stimulate osteogenesis and angiogenesis through the release of magnesium (Mg²⁺) ions. This study reports on composite scaffolds based on electrospun poly(ε-caprolactone) (PCL) fibres coated with MgP layers doped with lithium (Li) and zinc (Zn), designed to mimic the nanofibrous architecture of the extracellular matrix. Lithium and zinc were selected due to their known ability to modulate cellular response, with lithium promoting osteogenic activity and zinc contributing to improved cell proliferation and antibacterial potential. The phosphate phases obtained by coprecipitation were deposited onto the PCL fibres using Matrix-Assisted Pulsed Laser Evaporation (MAPLE), enabling controlled surface functionalization. Following thermal treatment, the formation of the crystalline magnesium pyrophosphate (Mg₂P₂O₇) phase was confirmed by chemical and structural characterization. The combination of a slowly degrading PCL matrix, providing sustained structural support, and a bioactive MgP coating, enabling rapid and controlled ion release, results in improved scaffold performance in terms of biocompatibility, biodegradability, and bioactivity. While the slow degradation rate of PCL ensures mechanical stability over an extended period, the surface-deposited MgP phase allows immediate interaction with the biological environment, facilitating faster ion release and enhancing cell–material interactions. These findings highlight the potential of the developed composites as promising candidates for trabecular bone regeneration and as viable alternatives to conventional CaP-based scaffolds in regenerative medicine. Full article

Background and Clinical Significance: Mallet finger is a common injury of the extensor mechanism at the distal interphalangeal (DIP) joint; however, open double mallet lesions are rare and may present a complex reconstruction challenge. Case Presentation: A 15-year-old male high school student who sustained an open injury to the left ring and little fingers after a high-energy buggy accident. The ring finger showed an open double mallet lesion in which the extensor tendon remained attached to a tiny avulsion fragment, and a separate dorsal base fragment was also present. The adjacent little finger had a concomitant open fracture with substantial soft tissue injury. Emergency surgery was performed on the day of the injury. For the ring finger, reduction of the tendon-attached avulsion fragment and separate dorsal base fragment was achieved using extension-block pinning, transarticular DIP pinning, and pull-out fixation over a volar button. For the little finger, cross-pinning was performed because the distal fragment was too small for stable non-transarticular fixation. Serial radiographs showed maintained alignment and progressive healing. At the final follow-up, 21 months after the injury, residual deformity and limitation of DIP motion remained; however, no infection, major skin complications, or nail deformity were observed. The little finger DIP joint became ankylosed, whereas some residual mobility remained in the ring finger DIP joint. Despite persistent functional limitations, the patient was able to continue school attendance and percussion-related activities. Conclusions: This case highlights that in an open double mallet lesion, disruption of both the tendon-attached fragment and its bony bed should be considered, and stabilization of the base may be useful in selected injury patterns before definitive tendon-side repair. Full article

Although internal fixation and surgical approaches promote fracture healing, some outcomes remain unsatisfactory. Advanced platelet-rich fibrin (A-PRF) has been shown to provide more growth factors, and in vitro cell proliferation has not been evaluated for treating bone fractures in veterinary medicine. The purpose of this study was to evaluate the bone-healing activity of A-PRF in traumatic canine fractures. Twelve dogs with single radius–ulna or tibia–fibula fractures were randomly assigned to two groups: a control group and an A-PRF group. Both groups were treated with a locking compression plate and screws and received pain control. Post-operatively, dogs were evaluated for serum C-reactive protein (CRP) levels and post-operative pain scores on days 1, 3, and 7. Lameness and weight-bearing scores were evaluated on days 1, 3, 7, 14, 30, and 60. Bone healing was assessed at 2 weeks, 1 month, and 2 months using calculated relative bone density (%). Compared with the control, the A-PRF group showed higher bone density at 2 months and lower lameness at 14 days post-operatively. Although the CRP level, an inflammation response marker, was higher in the A-PRF group within one day. No significant difference in pain score was observed. In conclusion, A-PRF serves as an effective adjunctive therapy for promoting bone healing when treating canine appendicular fractures with surgical internal fixation. Full article

Background: Pilon fractures refer to distal tibial fractures that may involve extra-articular, partial articular, or complete intra-articular components, most commonly caused by high-energy trauma. The choice between early (<72 hours) and delayed (>7 days) surgical fixation significantly impacts clinical outcomes. This study aimed to compare the effects of early vs. delayed plate fixation on fracture healing time, functional outcomes, and complication rates. Materials and Methods: This retrospective study analyzed 80 patients who underwent surgical treatment for pilon fractures between 2018 and 2023. Patients were divided into two groups: Early surgery (<72 hours, n=40); Delayed surgery (>7 days, n=40). Additionally, patients were categorized based on the fixation method: Single plate fixation (n=40); Double plate fixation (n=40). Outcome Measures: Fracture healing time (weeks) - Defined as cortical continuity on radiographs; Functional outcomes (AOFAS score); Complication rates (infection, malunion, implant failure). Results: Shorter healing time was observed in the early surgery group (14.2 vs. 16.8 weeks, p<0.05). Better functional outcomes were recorded in the early surgery group (AOFAS score: 82.3±6.5 vs. 78.1±7.2, p<0.05). Lower infection rates were noted in the delayed surgery group (7.5% vs. 12.5%, p<0.05). Double plate fixation provided better mechanical stability but resulted in higher soft tissue complication rates. Single plate fixation preserved soft tissue integrity but had higher malunion and implant failure rates. Conclusion: Early surgery is associated with shorter healing time and better functional outcomes, but increased soft tissue complications require careful management. Delayed surgery offers a safer approach for soft tissue healing but may prolong functional recovery. While double plate fixation ensures greater stability, it may increase soft tissue morbidity, whereas single plate fixation reduces soft tissue complications but may compromise stability. A personalized surgical approach is recommended for optimal outcomes in pilon fracture management. Full article

The effect of microstructural evolution on mechanical behavior of carbon/carbon composites after heat treatment has been investigated. Two kinds of samples, heat-treated at 2300 °C and 2700 °C, were used in the current study. As the heat treatment temperature is 2700 °C, the pyrolytic carbon acquires a higher orientation via carbon atomic layer rearrangement, accompanied by microstructural evolution such as self-healing of concentric ring cracks, narrowing of the fiber/matrix interface and bridging between adjacent fibers. This microstructural evolution results in a significant decline in the mechanical properties of the composites: compressive strength, flexural strength, and shear strength decreased by approximately 60%, 68%, and 71%, respectively, while the corresponding fracture strains increased by 52%, 25%, and 19%, respectively, indicating an improvement in pseudoplasticity. Full article