Search Results (163)

Background/Objectives: A third-generation atypical antipsychotic drug, aripiprazole, is known to cross the placental barrier and pose negative consequences on placental growth and the normal development of the fetus. Although a few studies demonstrated these debilitating effects of aripiprazole, its skeletal effects remain unexplored. Therefore, this study was undertaken to evaluate the impact of prenatal aripiprazole exposure, administered at three different dose levels, on the ossification of the appendicular skeleton in 20-day-old rat fetuses. Methods: Forty pregnant Sprague–Dawley rats (n = 40) were assigned to four groups: control and three aripiprazole-treated groups receiving 3 mg/kg (LDA), 6 mg/kg (HDA), and 12 mg/kg (DHDA) daily from gestational days 6–19. Fetuses were delivered on gestation day 20, weighed, and processed for skeletal evaluation using Alizarin Red S staining. Ossification patterns of metacarpals, metatarsals, hip bones, long bones of the forelimb and hindlimbs from a total of 151 fetuses were analyzed and categorized as complete, delayed, or absent. Results: Aripiprazole exposure induced a dose-dependent reduction in the number of completely ossified skeletal bony centers (p < 0.01) with a highly significant reduction in the length of ossified portions of the long bones (p < 0.001). Histomorphometric analysis of Von Kossa-stained fetal femur sections revealed a significant decrease in the thickness of ossified cortical and trabecular bone with a statistically significant reduction in the length of hypertrophied chondrocytes of the growth plate cartilage in the aripiprazole-treated groups (p < 0.05). Conclusions: Prenatal exposure to aripiprazole leads to dose-dependent skeletal growth restriction and delayed ossification of the appendicular skeleton in rat fetuses. Future investigations should focus on the molecular mechanisms and consequences related to the prenatal impact of aripiprazole. Full article

External skeletal fixation (ESF) is a versatile method for fracture management in neonatal calves but confers a significant risk of iatrogenic injury to vital structures. The aim of this ex vivo study was to systematically define safe, hazardous, and unsafe corridors for transcortical pin placement in the distal long bones (radius-ulna, tibia, metacarpus, and metatarsus) of Simmental calves to provide precise anatomical guidance. Six fresh Simmental calf cadavers without orthopaedic problems were included in the study. The forearm and hindlimb were disarticulated from the shoulder and hip joints, respectively. The radius-ulna, tibia, and metacarpal and metatarsal bones were dissected transversely from five anatomical levels. Safe, hazardous, and unsafe corridors were determined in each section. No safe corridor was found in the proximal metaphysis and proximal diaphysis of the radius-ulna. Safe corridors were found on the medial side of the radius-ulna, from the mid-diaphysis to the distal metaphysis. The metacarpal and metatarsal bones showed lateral and medial safe corridors. The tibia provided a continuous medial safe corridor. In conclusion, precise topographic mapping is vital for safe ESF. While anatomically safe corridors are the primary choice for ESF, hazardous corridors are viable alternatives if meticulously utilized. By contrast, unsafe corridors must be strictly avoided to prevent severe iatrogenic trauma. Full article

Background/Objectives: Calcium–phosphorus metabolism is critical for skeletal development in weaned piglets. This study evaluated the effects of dietary 25-hydroxyvitamin D₃ (25-OH-VD₃) in combination with phytase and probiotics on mineral metabolism, bone development, and related molecular mechanisms in weaned piglets. Methods: Sixty 28-day-old weaned piglets (7.1 ± 1.30 kg) were randomly assigned to four dietary treatments for 31 days (including 3 days of acclimation): CON (basal diet + 50 µg/kg 25-OH-VD₃), HI (CON + 50 mg/kg phytase), CY (CON +10 mg/kg probiotics), HICY (CON + 50 mg/kg phytase + 10 mg/kg probiotics). Apparent calcium digestibility, serum biochemical indices, bone mineral density (BMD), and mRNA and protein expression of calcium–phosphorus transport- and metabolism-related genes in jejunal mucosa and kidney were assessed. Results: Compared with CON, piglets in the HI, CY, and HICY groups showed higher apparent calcium digestibility (p < 0.05). Serum transforming growth factor-β was elevated in CY and HICY (p < 0.05). HI enhanced metatarsal and toe BMD (p < 0.05) and upregulated jejunal solute carrier family 34, member 2 (SLC34A2) and SLC34A3 mRNA expression (p < 0.05). In contrast, HICY reduced mRNA expression of transient receptor potential cation channel subfamily V member 6 and calcium-binding protein D28k, as well as of calcium-binding protein D9k and cytochrome P450 27B1 in the kidney (p < 0.05). Renal calcium-sensing receptor protein abundance increased in CY (p < 0.05). Conclusions: Supplementation of 25-OH-VD₃ with phytase and/or probiotics improved calcium utilization and modulated key transport pathways, contributing to enhanced bone development in weaned piglets. These findings highlight coordinated nutritional regulation of mineral metabolism during early post-weaning growth. Full article

Background/Objectives: Lisfranc joint injuries are complex midfoot pathologies frequently associated with subtle radiologic findings and delayed diagnosis. Although ligamentous disruption is considered the primary mechanism, the contribution of intrinsic osseous morphology remains insufficiently investigated. Previous studies have primarily relied on two-dimensional measurements and limited morphometric parameters. Therefore, this study aimed to provide a comprehensive three-dimensional (3D) computed tomography (CT) based morphometric evaluation of the medial and central columns of the Lisfranc joint and to determine whether specific bony parameters are associated with injury predisposition. Methods: A total of 48 CT scans, including 23 from patients with Lisfranc joint injuries and 25 from healthy controls without midfoot trauma, were retrospectively analyzed. For both groups, 3D models of the first three metatarsals (M1–M3) and cuneiforms (C1–C3) were reconstructed to measure bone length, articular surface areas, volumes, M1–M2/M2–M3 depth differences, and dorsal step-off (dorsal subluxation of M2 relative to C2). Correlations of these measurements with M2 length were additionally assessed in each group. Results: Comparisons between injury and healthy control groups revealed no significant differences in bony morphometrics (p > 0.05). Correlation analysis showed that a longer M2 were associated with greater cuneiform volumes and larger metatarsal articular surface areas (p < 0.05). Conclusions: This comprehensive 3D morphometric assessment of the Lisfranc joint indicates that intrinsic bony anatomy alone is unlikely to represent a primary predisposing factor for Lisfranc injuries. The observed positive relationship between M2 length and cuneiform articular surface areas and volumes demonstrates structural interdependence within the medial and central columns. Overall, injury susceptibility does not appear to be explained by variations in osseous morphology alone. Full article

Background: Hallux valgus (HV) is a complex forefoot deformity influenced by interactions between osseous alignment, ligamentous restraint, and muscle–tendon forces. While the biomechanical role of ligament laxity and bone geometry has been extensively investigated, the contribution of tibialis anterior (TA) tendon insertion variability to medial column mechanics remains insufficiently understood. Materials and Methods: A patient-specific finite element model of the foot was developed from high-resolution computed tomography data. Five anatomically documented TA distal insertion configurations were modeled, representing different distributions of attachment to the medial cuneiform and first metatarsal base. All simulations were performed under identical boundary and loading conditions representative of the stance phase of gait. Global (full-foot) and local (first bone and first metatarsal) mechanical responses were quantified using total deformation, equivalent von Mises stress, and strain distributions. Results: Marked differences in mechanical behavior were observed across TA insertion types. The metatarsal-dominant configuration (Type 3) demonstrated the highest global and local deformation values (global deformation: 1.0928 mm; first bone deformation: 1.0928 mm) and elevated strain distributions, whereas the medial-dominant configuration (Type 2) showed minimal deformation (global: 0.0727 mm; first bone: 0.0350 mm) but the highest global equivalent von Mises stress (5.7698 MPa). The single-band insertion to the medial cuneiform (Type 5) produced the greatest localized stress in the first bone region (3.8634 MPa). Representative strain maps revealed distinct spatial redistribution patterns within the medial column associated with TA insertion geometry. Conclusions: This patient-specific finite element analysis indicated that distal TA insertion variability alone can substantially modify deformation, stress, and strain patterns within the medial column. These findings suggested that TA insertion anatomy may act as a biomechanical modulator of first-ray mechanics and should be considered in future studies investigating hallux valgus pathomechanics and personalized treatment strategies. Full article

Cerebral palsy (CP) is a developmental disability caused by injury to the fetal or infant brain, affecting between 1.6 to 3.7 per 1000 live births worldwide. Ambulatory patients with cerebral palsy experience various gait problems, for which they seek treatment from medical professionals. Varus foot deformities are among the most problematic for patients. Varus foot deformity is characterized by the inner border of the foot being tilted upward and the hindfoot inward, increasing weightbearing on the lateral aspect of the foot. This positioning increases weight-bearing pressure under the lateral (outside) of the foot and often under the fifth metatarsal head when walking. As such, varus foot deformity can contribute to in-toeing, make shoe and brace-wearing difficult and painful, compromise gait stability, and sometimes lead to metatarsal fractures. Current knowledge of CP etiology and classifications, as well as principles and advances in assessment and treatment decision making for varus foot deformities, are outlined in this narrative review. In younger children with flexible deformities, non-operative interventions such as bracing, botulinum toxin injection, and serial casting are effective. The literature and expert consensus suggest that, if possible, surgery should be delayed until after the age of 8 years. When surgery is indicated, soft tissue procedures are used for flexible deformities. In addition to the soft tissue procedures, bone surgery is needed for rigid deformities. Careful pre-operative foot assessment is needed, including assessment of deformity flexibility and range of motion, X-rays, and computerized gait analysis if possible. Strategies are presented for thorough assessment when gait analysis is not available or feasible. Research reports of surgical outcomes for soft tissue and bony correction are positive, but should be interpreted with caution. The quality of evidence on surgical outcomes is compromised by use of varying research design methods and selection of outcome measures, with few including measures of function or patient-reported outcomes. It is recommended that surgical outcome be assessed using standardized assessment tools, such as the Foot Posture Index, which have had their validity and reliability established. Recent advances in 3D kinematic foot model development and musculoskeletal modeling have the potential to greatly improve surgical outcomes for patients with CP. Full article

Background: Congenital split foot/hand is a rare limb anomaly. Although various surgical techniques have been described, detailed gross anatomical studies of soft tissue adaptation, particularly in the foot, are extremely rare. This study presents a detailed anatomical description of a case of severe bilateral split foot. Methods: A comprehensive dissection was performed on the lower limb of a 64-year-old male donor with bilateral split foot/hand. Results: Radiographic evaluation classified the deformity as Blauth type IV, characterized by the absence of the lateral cuneiform bone and severe hypoplasia/aplasia of the second and third metatarsals. Significant changes were revealed in the musculotendinous apparatus. The key finding was a unique tendon loop passing through the central cleft, formed by the tendon of the extensor digitorum longus and connecting with the tendons of the flexor digitorum longus and flexor hallucis longus. Conclusions: This study presents the first detailed macroscopic anatomical description of split foot, demonstrating that this congenital anomaly involves complex, structured tendon and muscle adaptations that extend beyond skeletal deficiencies alone. The discovery of a persistent tendon loop—previously reported only once in split hand—indicates asynchronous development of skeletal and soft tissue structures. These findings should be taken into account for surgical planning, emphasizing the need to identify and manage such abnormal soft tissue structures during reconstructive procedures. Full article

Despite metals currently being widely used in orthopedic surgery, their mechanical properties significantly differ from the surrounding tissues and organs, causing low biocompatibility. Biodegradable, non-toxic, and non-immunogenic materials seem to be more convenient for clinical implementation. Our research was aimed at the construction of a polylactide screw covered with collagen, nanohydroxyapatite, and polylactide, with a variant including silver nanowires for antibacterial properties, as well as the analysis of their physico-chemical and biological properties. Adherent human osteosarcoma cells (2T line) were shown to grow on the porous surface layers. A cytotoxicity assay using WST1 revealed the non-toxic nature of the coatings and showed an increase in cell adhesion and proliferation. Safety and efficacy were also evaluated in vivo with the coated screws implanted into the metatarsal bones of minipigs. Histological analysis at 29 and 58 days post-screw-implantation revealed that the coated samples accelerated bone tissue regeneration compared to uncoated controls. This was evidenced by a higher bone-to-granulation tissue ratio, reduced inflammatory cell counts, and increased osteoblast/osteoclast activity at the early stage during the initial days after implantation. The results confirm that the developed bioactive coatings enhance biocompatibility and osteointegration. Full article

Despite manganese’s essential role as a cofactor for multiple enzymes, its potential to disrupt iron homeostasis when supplemented in excess remains a critical knowledge gap in swine nutrition. This study evaluated the effects of Mn (manganese)-supplemented diets on growth, hematology, mineral accumulation, digestibility, and intestinal iron transporter expression in weaned pigs. A total of 128 crossbred pigs (Duroc × Landrace × Largewhite) with an average body weight of 9.82 ± 0.15 kg were randomly allotted to four dietary treatments comprising a basal diet supplemented with 0, 20, 40, or 80 mg MnSO₄ per kg diet for 28 days. Blood samples were collected from 16 weaned pigs (1 pig per pen, 4 per treatment), after which animals were euthanized for tissue sampling. No differences were observed in growth performance. However, Mn concentrations in serum, liver, heart, kidney, pancreas, and metatarsal bones increased both linearly and quadratically with increasing dietary Mn (p < 0.05), and Fe (iron) concentrations in serum, hemoglobin, liver, and metatarsal bone decreased (p < 0.05). Apparent digestibility data further revealed that Mn absorption peaked at 20 mg/kg, while Fe digestibility declined linearly with increasing Mn levels. Moreover, duodenal DMT1 (divalent metal transporter 1) mRNA expression was decreased, whereas FPN1 (ferroportin 1) was upregulated. These findings demonstrate that excessive Mn supplementation impairs dietary Fe absorption and homeostasis in weaned pigs, suggesting that the antagonism occurs at both the transcriptional and intestinal absorption levels, providing critical insights for dietary formulation in swine. Full article

Background/Objectives: Flexible symptomatic flat foot in children can be surgically treated with calcaneus stop screws. This raises the question of whether pre- and postoperative radiographs (X-ray) can be analyzed in two planes using AI. Methods: In this monocentric retrospective study, angle measurements generated by Bone Metrics AI (Gleamer) were compared with manual measurements using Centricity™ (GE Healthcare). A total of 659 X-rays from 124 operated feet (2014–2024) were available, of which 422 were analyzable by AI and 299 met defined quality criteria. Bland–Altman plots were used to assess agreement. Linear and logistic regression analysis examined the influence of age, gender, accessory navicular bone, additional foot pathologies, and flat foot severity on comparability of the measurement methods and measurability by the AI. Finally, radiographs meeting and missing quality criteria were compared. Results: AI measurements were comparable to manual measurements for calcaneus inclination, hallux valgus, 1st–2nd and 1st–5th metatarsal angle both pre- and post-operatively. For the talus-1st metatarsal and medial arch angles, AI results differed significantly (p < 0.001 and p ≤ 0.013) from manual measurement. AI generated talus-1st metatarsal angle was measured larger by 6.14°, 95% [−7.14; −5.14] pre-operatively and 2.80°, 95% [−3.79; −1.81] post-operatively. Medial arch angle was smaller by 1.63° pre-operatively, 95% [1.03; 2.23] and 0.52° post-operatively, 95% CI [0.11; 0.93] with AI. Post-operative measurability was not significantly lower than pre-operative. AI measured angles on incorrectly taken radiographs as often or more often than on correctly taken ones. Discussion: Screw implantation did not negatively impair measurability or AI accuracy. However, age, gender, and flat foot severity influenced AI performance. Bad radiograph quality did not affect AI measurability negatively, indicating that AI cannot yet distinguish between X-rays suitable and unsuitable for angle measurements. Conclusions: Manual measurements are still indispensable in the diagnosis of children’s flat feet. In the future, continuous training of the AI is expected to bring it into line with manually measured radiological values. Full article

(1) Background: Cone beam computed tomography (CBCT) is increasingly used in equine practice to diagnose musculoskeletal injuries, including fractures in the distal limb. However, limited detail in the thick cortical bone of the metacarpus/metatarsus hinders accurate diagnosis. In human medicine, the addition of aluminum filters (AF) enhanced image quality while reducing radiation exposure. This study aimed to evaluate the effect of AF on image quality in CBCT scans of equine distal limbs. (2) Methods: Adult equine cadaver limbs were scanned with a mobile CBCT unit using varying tube currents (10–100 mA) and AF (13–25 mm). Two independent experts assessed the image quality using a four-point visual grading scale, focusing on cortical bone detail and artifacts. (3) Results: Higher tube currents generally improved image quality, but no filter was beneficial for the metacarpal/metatarsal regions. For the proximal phalanx, thicker AF (19–25 mm) improved image quality without significantly increasing the required tube current. (4) Conclusions: The optimal balance between image quality and radiation exposure using the O-arm^® CBCT system for equine distal limbs was a tube current of 50 or 64 mA without filtration for the metacarpus/metatarsus, while a tube current of 50 mA with a 19–25 mm AF provided the best image quality for the proximal phalanx. Full article

Background: Medial columnnails have been introduced intoCharcot’s neuroarthropathy reconstruction as superconstruct fixation with high fatigue strength and pullout resistance. Similar to intramedullary nailing throughout other long-bone fixation, injury to neurovascular and musculotendinous structures secondary to percutaneous interlocking screwfixationmay exist.We sought to identify structures at risk for injury during the interlocking of amedial column nail. Methods: Medial column nails were inserted into ten cadaveric limbs. The proximal (talar), middle (first metatarsal), and distal (first metatarsal) locations for the interlocking screws were drilled, and a 0.062 Kirschner wire was inserted into respective drillholes to simulate interlocking screws. After dissection, the distances of each Kirschner wire to nearby anatomical structures were measured. Levels of risk were assigned to each soft-tissue structure based on distance to each Kirschner wire: high (0–3.5 mm), intermediate (3.6–7.0 mm), and low (> 7.0 mm). A 3.5-mm threshold for each category was used because this represented a multiple of the diameter of the interlocking screws. Mean ± SD and ranges are reported for structures at high and intermediate risk for injury. Results: Proximally, the deltoid ligament (ten of ten), posterior tibial tendon (eight of ten), and saphenous vein (six of ten) were at high or intermediate risk for injury consistently. At the middle screw, the medial dorsal cutaneous nerve and the medial marginal vein were at high or intermediate risk in ten and eight specimens, respectively. At the distal interlocking screw, the medial dorsal cutaneous nerve was at high risk for injury in all ten specimens. Conclusions: There is high and intermediate risk to many musculotendinous and neurovascular structures when performing percutaneous interlocking screws in a medial column nail. These findings serve to educate surgeons of the anatomical considerations they must have when performing medial column nailing for reconstruction of Charcot’s foot. Full article

This study presents a three-dimensional finite element (FE) analysis of the human foot bone structure under mid-stance loading during race walking. A subject-specific biomodel comprising 26 bones and over 40 ligaments was reconstructed from computed tomography (CT) data using Materialise Mimics Research 21.0 and 3-Matic Research 13.0, and subsequently analyzed in ANSYS Workbench 2024 R1. The model included explicit cortical, trabecular, and ligamentous volumes, each assigned linear-elastic, isotropic material properties based on biomechanical literature data. Boundary conditions simulated the mid-stance phase of race walking, applying a distributed plantar pressure of 0.25 MPa over the metatarsal and phalangeal regions. Numerical simulations yielded maximum total displacements of 0.00018 mm, maximum von Mises stresses of 0.171 MPa, and maximum strains of 2.5 × 10⁻⁵, all remaining well within the elastic range of bone tissue. The results confirm the model’s numerical stability, geometric fidelity, and capacity to represent physiologically realistic loading responses. The developed framework demonstrates the potential of high-resolution, image-based finite element modelling for investigating stress–strain patterns of the foot during athletic gait, and establishes a reproducible reference for future analyses involving pathological gait, orthotic optimisation, and musculoskeletal load assessment in sports biomechanics. Full article

Background: Jones fractures of the 5th metatarsal are frequently associated with nonunion due to limited vascularization and repetitive mechanical stress. The aim of the study was to compare the biomechanical performance of T-plate and bicortical screw fixation using standardized 3D models. Methods: Three-dimensional models of the 5th metatarsal were generated from CT images and printed using PolyJet technology (Stratasys J5 DentaJet) using a rigid-elastic composite with properties similar to cortical and cancellous bone. Jones fractures were fixed with either a locked T-plate or a bicortical screw. The samples were tested under axial and oblique static loads (α = 0°, 90°, 180°) and for three values of interfragmentary distance (d = 0.1–1 mm), in a 3 × 2 factorial design. Results: The T-plate fixation recorded a maximum yield force (Fmax) of 149.78 ± 8.53 N (138–161 N), significantly higher compared to the bicortical screw −98.56 ± 2.58 N (96–101 N), (p < 0.05). The ductility index was higher for the plate, indicating a progressive transition to yield. The α and d factors significantly influenced the mechanical behavior, with the polynomial model explaining over 95% of the total variation. Discussion: The plate fixation demonstrated greater strength and superior biomechanical tolerance in imperfect reduction scenarios. The main limitation is the lack of fatigue testing and the inability of 3D models to reproduce the structural heterogeneity of human bone. Conclusions: Implant selection should be individualized based on fracture stability. 3D models provide a reproducible platform for comparative evaluation of osteosynthesis methods, but future studies should include cyclic loading and biological validation. Full article

Background and Objectives: The anesthetic nerve block test is a surgical technique that can assist in the differential diagnosis of forefoot pain. The MTP joint, enclosed by its capsule, may act as a sealed cavity with predictable contrast dispersion, whereas the IM space, lacking clear boundaries and containing bursae and the plantar digital nerve, favors diffuse spread. Due to the high rate of false positives in suspected cases of Morton’s neuroma with the anesthetic block current procedure in the intermetatarsal space, the aim of this study was to propose an alternative to the current procedure. Material and Methods: Six fresh cadaveric feet were used. Under ultrasound guidance, the 2nd–4th MTP joints received stepwise intra-articular injections of radiopaque contrast. The third common digital nerve was injected within the third intermetatarsal space. Standard radiographs were obtained to assess distribution and proximal spread. Results: A volume of 0.3 mL was sufficient to fully reach the intra-articular cavity and potentially induce effective localized anesthesia. When the third common digital plantar nerve was injected in an anatomically healthy region, the contrast medium showed a proximal diffusion pattern extending up to the mid-diaphyseal level of the third and fourth metatarsal bones. On radiographs, the intra-articular infiltration lines appear sharply demarcated, supporting the interpretation of the metatarsophalangeal joint as a sealed compartment. Conclusions: Low intra-articular anesthetic volumes may yield targeted effects, while Morton’s neuroma injections spread proximally, risking loss of diagnostic specificity; this technique may improve decision-making accuracy and reduce failures. Full article