Search Results (875)

Birmingham hip resurfacing (BHR) is an alternative to bone-sparing total hip arthroplasty; however, failures may be associated with the cementing technique. This study aimed to evaluate the characteristics of the cement layer and potential failure mechanisms. BHR explants were analyzed using radiographic evaluation, stereomicroscopy, scanning electron microscopy (SEM), and histopathology. The cement layer was nonuniform, with excessive thickness in the dome regions and insufficient lateral coverage. Increased cement penetration values exceeded recommended thresholds. SEM analysis revealed inhomogeneous cement with cracks, air inclusions, and loosening at the cement–prosthesis interface. BHR failure may be associated with a complex interplay between cementation parameters, cement mantle morphology, and the biological response at the bone–cement interface, as well as interactions at the cement–prosthesis interface. Microscopic evaluation may provide valuable insights into the mechanisms potentially contributing to BHR prosthesis failure. Full article

Background: The management of bone defects in pediatric oncology represents a major challenge in orthopedics, as it requires preserving both joint function and skeletal growth. Traditional reconstructive approaches, such as autografts and allografts, are limited by availability, complications, and incomplete biological integration. In this context, xeno-hybrid bone substitutes have emerged as a promising alternative. The aim of this study was to evaluate the safety and effectiveness of SmartBone^® ORTHO in the reconstruction of post-oncological bone defects in children. Methods: Twelve pediatric patients treated at the Centro Traumatologico Ortopedico (CTO) and OIRM Hospital, AOU Città della Salute e della Scienza of Turin (Italy), between 2016 and 2019 were retrospectively analyzed. Lesions included simple and aneurysmal bone cysts, non-ossifying fibroma, chondroblastoma, and other benign conditions. All patients underwent curettage followed by defect filling with SmartBone^® ORTHO. Results: At clinical and radiological follow-up, nine patients (75%) showed stable graft integration and complete functional recovery. Three patients (25%) developed local recurrence, which was managed with revision surgery and re-implantation of SmartBone^®, with all achieving stable outcomes. Radiographs demonstrated progressive increases in bone density and trabecular thickness, reaching values comparable to those of native bone within 6–12 months. Conclusions: SmartBone^® ORTHO proved to be a safe and effective biomaterial for pediatric post-oncological bone reconstruction, promoting rapid osteointegration and physiological bone remodeling without infection or intolerance. Full article

Sheep farming length of stay in the feedlot directly influences system profitability, mainly due to the high cost of feed. Thus, the use of predictive models based on body measurements is an important tool to define the optimal slaughter point and the ideal feedlot period. Thus, the aim was to evaluate predictive models of meat cuts and tissue carcasses concerning weight at slaughter (WS), loin eye area (LEA), and subcutaneous fat thickness (SFT) obtained by ultrasound of the lumbar region of lambs. The WS and ultrasound measurements were obtained from a pre-slaughter collection of 45 lambs, divided into five groups, each weighing 15, 20, 25, 30, or 35 kg, with nine replications per group. Three regression models were evaluated: WS, LEA, and SFT (independent variables) and the cuts yield or tissue composition (dependent variable). Increasing WS resulted in greater carcass weight and commercial cuts. Above 15 kg body weight, bone weight showed little or no increase (allometric coefficient = 0.06), whereas muscle and fat tissues increased steadily, with allometric coefficients of 0.25 and 0.12, respectively. The commercial cuts showed a high and significant correlation with WS and LEA. The muscle and bone proportion of the leg had a significant (p < 0.10) correlation with SFT. For the weight of commercial cuts estimates, the inclusion of LEA and/or SFT with WS did not improve the coefficient of determination but made the predictions equivalent to the measured values. There were high determination coefficients when WS was only used to predict muscle, fat, and bone weight, but it was not efficient in predicting the muscle/fat and muscle/bone ratios and the percentage of tissues. The WS was the variable that best explained the weight and tissue content. The inclusion of LEA and/or SFT made little improvement to the predictive models. Full article

By using virtual surgical planning (VSP) and 3D printed guides, complex maxillofacial defects can be reconstructed with high accuracy and predictability. A fully digital workflow resulting in a modular all-in-one 3D printed guide system for fibula osteotomies, bone segment positioning, fully guided dental implant placement and dental prosthesis fixation for mandibular reconstruction was developed at Ghent University Hospital. A follicular ameloblastoma of the left mandible was resected in a 28-year-old male. The defect was reconstructed with a two-segment fibular free flap with immediate placement of three dental implants and immediate implant loading with a screw-retained bridge. A split thickness skin graft and Elemental PerioPlast were used as wound dressing. Comparison of the preoperative planning with the postoperative CT-scan showed a deviation immediately after surgery, which was no longer present at the 6-month follow-up. The patient achieved a stable occlusion and 44 mm mouth opening and reported high satisfaction. This case illustrates that fully digital, immediate mandibular reconstruction with simultaneous implant placement and prosthetic rehabilitation is feasible and accurate and enhances early functional recovery. Future improvements in intraoperative validation may further refine accuracy and reproducibility in complex oncologic reconstructions. Full article

It is widely accepted that modern humans display distinctive vertebral and intervertebral disc (IVD) morphologies that evolved to meet the biomechanical demands of habitual terrestrial bipedalism. This study synthesizes macro- and microstructural differences in the lumbar spine to clarify how human specializations compare with those of extant apes. The skeletal sample consisted of 240 humans, 20 chimpanzees, and 25 gorillas. The CT scan sample comprised 180 humans and eight chimpanzees. Histological analysis of the IVD was performed on 10 humans and four ape specimens. Vertebral bodies and discs were measured. Histological analyses employed hematoxylin–eosin, Von Kossa, and Van Gieson staining. Statistical analyses included ANOVA with Bonferroni-corrected t-tests or Welch’s ANOVA and Games–Howell post hoc tests. Regression analyses were performed using ordinary least-squares estimation, and differences between regression lines were assessed using ANCOVA. Humans and chimpanzees differed significantly in vertebral body proportions, bone volume fraction, IVD thickness, apophyseal ring thickness, annulus fibrosus lamellar organization, endplate and subchondral bone thickness, and vascularization at the bone–endplate interface. These results indicate substantial evolutionary modification of the human vertebral body and IVD, enhancing rotational mobility and resistance to axial loading, key functional requirements for maintaining upright posture and efficient bipedal locomotion. Full article

Objectives: To determine the most favourable Micro-Implant (MI) insertion site along the mandibular buccal shelf (MBS), using Cone Beam Computed Tomography (CBCT). Methods: This retrospective study assessed CBCT scans from 90 Portuguese patients (32 males and 58 females, aged 14 to 40 years). Paired MBS sites were determined. Comparative and correlation analyses were performed at p < 0.05. Results: A significant increase in MBS width was observed from the mesial to the distal direction (p < 0.001). Conversely, both the MBS steepness and cortical bone thickness significantly decreased from mesial to distal (p < 0.001). Significant negative correlation was also found between age and cortical bone thickness adjacent to the distobuccal cusp and distal tangent of both mandibular second molars (r ≤ −0.373, p ≤ 0.007). Furthermore, significant asymmetric differences were identified between the right and left MBS steepness as well as in the paired cortical bone thickness at the mesiobuccal cusp, buccal groove, and distobuccal cusp of the mandibular second molar (p ≤ 0.016). Conclusions: The results indicate that although there are sufficient MBS width and cortical bone thickness, vestibular to the mandibular second molar for MI insertion, the sites towards the distal root of the mandibular second molar are more favourable when considering MBS steepness. These findings are consistent for both sexes and apply to young and old individuals. Full article

Background/Objectives: Vitamin D plays a central role in calcium and bone homeostasis; however, evidence linking serum 25-hydroxyvitamin D (25(OH)D) to bone mineral density (BMD) in postmenopausal women remains inconsistent. Because body weight and lean mass strongly influence skeletal loading and may also affect circulating 25(OH)D, we aimed to evaluate the association between serum 25(OH)D and bone outcomes in early postmenopausal women and to determine whether body composition attenuates this relationship. Methods: In this cross-sectional study, 120 women within 10 years after natural menopause (59.5 ± 6.3 years) were assessed. Serum 25(OH)D was measured by chemiluminescent immunoassay. Total body areal bone mineral density (total body aBMD, g/cm²) was assessed by DXA, and trabecular volumetric BMD and cortical thickness were obtained using 3D modeling. Associations were examined using Spearman correlations and multivariable linear and logistic regression models adjusted for age, body weight, lean mass, and years since menopause. Results: Median serum 25(OH)D was 23.7 ng/mL [16.7–30.4]. A modest correlation was observed between 25(OH)D and total body aBMD (ρ = 0.22, p = 0.016), but not with trabecular volumetric BMD or cortical thickness. After adjustment, 25(OH)D was not independently associated with total body aBMD (p = 0.144), whereas body weight remained significantly associated (β = 0.27, p = 0.002). In logistic models, body weight (OR = 0.93, 95% CI 0.90–0.96) and lean mass (OR = 0.97, 95% CI 0.95–0.99) were protective against low BMD, while the association with 25(OH)D was modest. Conclusions: In early postmenopause, the association between serum 25(OH)D and BMD is modest and largely attenuated after accounting for body composition. Body weight and lean mass appear to be stronger determinants of bone outcomes than vitamin D status. Full article

Porous scaffolds fabricated via fused deposition modeling (FDM) are promising for bone tissue engineering, but their mechanical performance and geometric fidelity are governed by complex interactions between process parameters and architectural design. This study presents a multi-objective optimization framework for poly (lactic acid) (PLA) scaffolds based on three triply periodic minimal surface (TPMS) topologies—Gyroid, Primitive, and Diamond. A Box–Behnken design combined with response surface methodology was used to model compressive strength, elastic modulus, yield strength, energy absorption density, and discrepancies in volume and porosity as functions of layer thickness (0.05–0.15 mm), extrusion temperature (210–220 °C), and target porosity (50–70%). The resulting quadratic models exhibited strong predictive capability (R² > 77%, with most >90%) and were validated experimentally at extreme parameter combinations, yielding relative errors below 10% for 83% of measurements. Multi-objective optimization using NSGA-II, coupled with principal component analysis and correlation-based objective reduction, revealed that the six original objectives collapse to topology-specific essential pairs: absorbed energy density and porosity discrepancy for Gyroid; Young’s modulus and volume discrepancy for Primitive; and Young’s modulus and porosity discrepancy for Diamond. The generated Pareto fronts quantify the inherent trade-off between mechanical performance and geometric fidelity for each topology, providing designers with explicit decision maps. This framework enables rational, application-driven selection of printing parameters and scaffold architecture, advancing the clinical translation of patient-specific FDM-printed bone scaffolds. Full article

Background/Objectives: Adequate peri-implant soft tissue thickness is essential for long-term peri-implant health and esthetics. Horizontal platelet-rich fibrin (H-PRF) has been proposed to support soft tissue regeneration; however, experimental and translational evidence for its application in peri-implant soft tissue augmentation remains limited. This study aimed to evaluate a H-PRF membrane block approach primarily through an experimental animal model, with clinical cases presented to illustrate translational feasibility. Methods: A customized compression device was used to fabricate the H-PRF membrane block. The biological performance of the H-PRF membrane block was first evaluated in a rabbit model, with histologic assessment of peri-implant soft tissue thickness and integration at 8 weeks. Representative clinical cases requiring peri-implant mucosal thickening were subsequently treated with H-PRF membrane block on the buccal aspect of the alveolar bone beneath a supra-periosteal flap to demonstrate clinical applicability. Results: In the animal model, the H-PRF membrane block resulted in a significant increase in peri-implant soft tissue thickness by increasing the lamina propria compared with control sites demonstrated by histologic analysis. The clinical illustrations showed stable buccal soft tissue volume and contour with minimal patient morbidity. Conclusions: Within the limitations of this experimental study, the horizontal H-PRF membrane block technique demonstrated promising biological performance for peri-implant soft tissue augmentation in an animal model. The accompanying clinical illustrations support the translational feasibility of this approach. Clinical relevance: This experimental study provides biological and translational insight into a minimally invasive strategy for peri-implant soft tissue thickening and may inform future controlled clinical investigations. Full article

Background: Limb-salvage surgery using extendable distal femoral endoprostheses has become the standard reconstruction following tumor resection in skeletally immature patients, allowing continued growth and improved function. However, mechanical complications, particularly tibial pain, remain challenging and poorly understood. This study aimed to identify radiographic predictors of tibial pain and evaluate their potential utility in early risk detection. Methods: A retrospective cohort study was conducted of 29 skeletally immature patients (mean age 10.4 years) who underwent expandable distal femoral endoprosthetic replacement between 2008 and 2018 at a tertiary orthopedic oncology center. Standardized radiographs were analyzed at 6 months and final follow-up (mean 75 months) to assess cortical thickness, stem-to-cortex distances, stem migration, stress shielding, pedestal formation, and periosteal reaction. Associations between radiographic parameters and tibial pain were assessed using multivariable logistic regression, t-tests, and chi-square analyses. Results: Seventeen patients (58.6%) developed activity-limiting tibial pain requiring analgesics, as documented during follow-up. Mean medial and lateral cortical thickness increased from 3.0 mm and 3.4 mm to 4.1 mm and 5.1 mm, respectively. The logistic regression model demonstrated strong explanatory power (Pseudo R² = 0.57, p = 0.004). Medial cortical thickness at last follow-up was the only significant independent predictor of tibial pain (p = 0.042), and was significantly associated with tibial pain. Patients with tibial pain exhibited greater medial cortical thickening (p < 0.001). Stem migration (φ = 0.421, p = 0.065), stress shielding (φ = 0.476, p = 0.044), pedestal formation (φ = 0.608, p = 0.004), and periosteal reaction (φ = 0.569, p = 0.008) were also associated with pain. Conclusions: Medial cortical hypertrophy emerged as a potential radiographic biomarker for tibial pain. after expandable distal femoral endoprosthesis in growing patients. The findings suggest that cortical remodeling, stress shielding, and pedestal formation collectively reflect stem micromotion and bone adaptation. Early radiographic surveillance of these parameters warrants further investigation in prospective studies to determine their clinical utility. Larger multicenter studies are warranted to validate these predictors and refine postoperative monitoring protocols. Full article

Background/Objectives: The aim of this study was to identify predictors of temporal window failure (TWF) in transcranial color-coded duplex sonography (TCCS) based on demographical and computed tomography (CT)-based parameters such as temporal bone thickness (TBT), and to define sex-specific thresholds for predicting TWF. Methods: We retrospectively analyzed a series of adult patients who underwent cranial CT and TCCS. Bitemporal TBT was measured in nine standardized regions on CT, and mean TBT per side was calculated. Temporal bone window (TBW) quality was graded with two semiquantitative TCCS scores assessing the visibility of the middle cerebral artery (MCA), contralateral temporal bone, mesencephalon, and ipsilateral sphenoid bone. Associations between TBT, sex, age, and TBW visibility were analyzed by correlation, chi-square tests, and logistic regression. Results: 200 patients (102 men, 98 women; mean age 68 ± 16 years) were enrolled. Mean TBT was 3.1 ± 0.7 mm (right) and 3.2 ± 0.7 mm (left). TBT correlated weakly with age (r = 0.15–0.18, p < 0.05) and was higher in women (p < 0.05). Age and sex influenced TBW visibility (p < 0.05) with small effect sizes. Increased TBT strongly predicted poor TBW (β ≈ –1.7, p < 0.001). Optimal TBT cut-offs predicting adequate TBW were 3.8 mm (men) and 3.3 mm (women), maximizing specificity (men: 0.95, women: 0.85) and negative predictive value (men: 0.87, women: 0.66). Conclusions: Advanced age and female sex were both associated with TWF. CT-assessed TBT represents a robust predictor of TCCS feasibility. Implementation of sex-specific TBT threshold values may facilitate patient pre-selection and improve procedural efficiency in neurosonographic diagnostics. Full article

Background: The extracellular matrix (ECM) plays a central role in the mechanical strength and functional integration of tissue-engineered matrix (TEM), particularly in cardiovascular and load-bearing applications. Mesenchymal stromal cells (MSCs) from different sources may vary in their ECM-forming potential. Methods: In this study, adipose-derived (hADMSC), bone marrow-derived (hBMSC), and umbilical cord-derived MSCs (hUCMSC) were compared with human dermal fibroblasts (HDFBs) as a reference. Cells were seeded onto polyglycolic acid (PGA)/poly-4-hydroxybutyrate (P4HB) scaffolds and cultured for 3 weeks under static or hydrodynamic conditions using orbital shaking. TEM development was assessed macroscopically, histologically (using H&E and Masson’s trichrome stains), and by polarized light microscopy (Picrosirius Red), alongside biochemical assays that quantified DNA, glycosaminoglycan (GAGs), and hydroxyproline (HYP). Results: Hydrodynamically stimulated culture consistently improved ECM deposition across all groups. TEMs exposed to hydrodynamic stimulation (hydrodynamic conditions) were thicker, more uniformly filled, and exhibited increased collagen deposition compared with static TEMs, which remained thinner and showed persistent scaffold remnants. Polarized light analysis demonstrated that dynamic loading promoted collagen maturation in all groups, as evidenced by an increased prevalence of thick, birefringent collagen fibers indicative of mature collagen. Biochemical analyses showed that HDFB-derived TEMs produced the highest total collagen and ECM content under both static and hydrodynamic conditions; however, these matrices remained comparatively thin and densely packed. In contrast, MSC-derived TEMs formed thicker and more spatially distributed ECM in response to hydrodynamic stimulation. Conclusion: Among the MSC sources, hUCDMSC-derived TEMs exhibited the most advanced collagen maturation and the most uniform collagen distribution under hydrodynamically stimulated culture, whereas hADMSC-derived TEMs showed the greatest matrix thickening and volumetric ECM expansion with intermediate collagen maturation. hBMSC-derived TEMs displayed clear responsiveness to hydrodynamic stimulation but remained limited in overall collagen deposition and fiber maturation. These findings underscore that both hydrodynamic stimulation and cell source are critical not only for maximizing ECM deposition, but also for ensuring physiologically relevant collagen maturation and matrix organization in grafts suitable for clinical translation. Full article

Background: Osteosarcoma is the most common primary malignant bone tumor in children and adolescents. At present, multi-agent chemotherapy and surgery provide only limited effects and the prognosis for patients with recurrent or metastatic disease remains poor, with 5-year survival rates below 30%. These challenges highlight the need for innovative therapeutic approaches targeting osteosarcoma more effectively. Fenretinide, a synthetic derivative of all-trans retinoic acid, has shown significant antitumor activity in various cancers. In a recent high-throughput drug screening study, fenretinide emerged as the most active molecule against diffuse midline glioma over more than 3500 compounds. Fenretinide also demonstrated cytotoxic activity against osteosarcoma cell lines in vitro and in preclinical models and is endowed with a favorable safety and toxicity profile. However, its poor water solubility and limited bioavailability have hindered its clinical translation. To improve fenretinide bioavailability and enhance tumor exposure, different nanotechnology-based drug delivery systems have been proposed. Here we propose a tertiary complex made of fenretinide, bovine serum albumin, and hydroxypropyl-betacyclodextrin, indicated as BSAF. Methods: BSAF was evaluated for the main physico-chemical parameters such as hydrodynamic size, zeta potential, stability to drug leakage, and the biological effect on the osteosarcoma cell line MG63. Results: BSAF showed hydrodynamic size at the nanoscale, enhanced drug solubilization, high drug loading and size stability to dilution, characteristics that make this complex useful for targeted therapy. When tested on the MG63 osteosarcoma cell line, BSAF demonstrated significantly enhanced cytotoxicity, with half-maximal inhibitory concentration (IC₅₀) values ~50% lower than free fenretinide. The complex was more efficient than free fenretinide in inhibiting cell migration as demonstrated by wound healing assay. Live-cell imaging analyses revealed a cytostatic effect at sub-cytotoxic concentrations. Specifically, treatment with concentrations below the IC₅₀ resulted in significantly prolonged cell doubling time, decreased cell divisions, increased cellular sphericity and thickness, and decreased cell area. These morphological changes are more consistent with cell cycle arrest rather than apoptosis. These findings were corroborated by stable dry mass measurements, an indication of a cytostatic state rather than progressive cell death. In addition, cell motility parameters (e.g., instantaneous velocity, track speed, and displacement) at the single-cell and population level were markedly reduced at sub-IC₅₀ concentrations, further supporting a cytostatic phenotype. Conclusions: Collectively, the new BSAF complex showed promise as a potential therapeutic agent for treating osteosarcoma cancer, due to the favorable physico-chemical characteristics and the cytotoxic/cytostatic effects on MG63 cells. BSAF effects may be therapeutically valuable, particularly in preventing tumor recurrence by suppressing the proliferative and migratory potential of residual drug-resistant clones. Unlike conventional anticancer agents that mainly rely on cell death, fenretinide, when complexed, demonstrates a dual capacity to induce both cytotoxic and cytostatic responses, depending on concentrations, potentially overcoming multiple resistance mechanisms that are generally associated with tumor exposure to drug sub-cytotoxic concentrations. Full article

In implant treatment in the aesthetic zone, high aesthetic quality is required in addition to functionality and long-term stability when reconstructing defects in peri-implant tissues. Post-traumatic cases often present with extensive loss of both hard and soft tissues, making the selection of an appropriate grafting method essential. This report describes a case in which an interpositional gingival graft (IGG) and a strip gingival graft (SGG) were combined to regenerate peri-implant soft tissue following guided bone regeneration (GBR), maintaining favorable tissue morphology and aesthetics for six years. The patient was a 53-year-old woman who suffered trauma after falling down stairs, resulting in a fractured bridge in the right maxillary canine region and crown fracture. The traumatized tooth was extracted, and GBR was performed to restore hard tissue volume. Subsequently, IGG and SGG were used to improve soft tissue thickness, interproximal papilla height, and a healthy mucogingival junction (MGJ). A cantilever implant prosthesis was selected as the final restoration. Over six years, no gingival recession or marginal bone loss was observed, and excellent aesthetic stability was maintained. A mini-review of published reports on IGG and SGG demonstrated their efficacy in enhancing soft tissue volume. The findings of this case suggest that a comprehensive approach—including bone augmentation, soft tissue grafting, and prosthetic design—can provide predictable, long-term aesthetic and functional outcomes in complex post-traumatic cases (223). Full article

Background/Objectives: Although unrestricted kinematic alignment (uKA) has gained increasing acceptance in total knee arthroplasty (TKA), its application in knees with lateral compartment osteoarthritis (OA) remains a subject of debate due to concerns over postoperative gap imbalance and alignment outliers. The purpose of this study was to evaluate the surgical, radiographic, and clinical outcomes of contralateral non-OA knee–referenced, caliper-verified uKA in lateral compartment OA. Methods: This retrospective study included 40 patients with isolated lateral compartment OA who underwent primary TKA using contralateral non-OA knee–referenced, caliper-verified uKA. Surgical outcomes were assessed by measuring bone resection thicknesses of the distal femur, posterior femur, and proximal tibia, as well as extension and 90° flexion gaps. Radiographic outcomes included mechanical hip–knee–ankle angle, medial proximal tibial angle, lateral distal femoral angle, and Coronal Plane Alignment of the Knee (CPAK) classification. Patient-reported outcomes (PROs), including Pain VAS, EQ-5D, satisfaction, and Forgotten Joint Score, were assessed at a minimum follow-up of 2 years. Results: The resected osteochondral thickness was consistently greater on the medial side than on the lateral side, and all gap balances were well maintained, with a gap difference ≤ 2 mm observed in 95% of knees in full extension. Postoperatively, restoration to the same CPAK category was achieved in approximately 90% of cases. All PROs improved and reached levels comparable to those of the contralateral knee. Conclusions: In patients with lateral compartment OA, caliper-verified uKA may be appropriately applied when guided by a reliable anatomic reference, such as the contralateral non-OA knee. This strategy achieves stable soft-tissue balance, reliable coronal alignment restoration, and favorable clinical outcomes in carefully selected valgus knees undergoing TKA. Full article