Search Results (516)

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

Smart insoles equipped with pressure sensor matrices are increasingly used for gait analysis, yet high-density arrays compromise battery life and data throughput. This study aims to identify the optimal sparse sensor layout required to accurately estimate the Center of Pressure (CoP) by analyzing the trade-off between sensor number, spatial placement, and reconstruction error. Plantar pressure data were collected from twelve healthy participants walking at a self-selected speed using 16-sensor connected insoles. A combinatorial algorithm evaluated all $2^{16}-1$ possible sensor combinations to minimize the Root Mean Square Error (RMSE) in the antero-posterior, medio-lateral, and global Euclidean directions. Results reveal a non-linear convergence of accuracy that depends on the spatial axis. For longitudinal and global progression, a clear inflection point achieving sub-centimetric accuracy (RMSE < 5 mm) is reached at seven sensors. In contrast, medio-lateral tracking shows its largest discrete error reduction at five sensors, followed by gradual improvements at higher densities. Anatomical frequency analysis highlights distinct spatial requirements: the posterior heel is consistently selected for medio-lateral accuracy, while the lateral arch and metatarsal regions are critical for longitudinal progression. These findings suggest that while a minimum of seven strategically placed sensors enables robust CoP tracking across all spatial axes, optimal hardware design should remain task-specific. This work provides a data-driven framework for the development of energy-efficient wearable gait monitoring systems. Full article

Background: We present a retrospective radiographic analysis showcasing the ability to correct hallux valgus using the Lapidus arthrodesis without focused frontal plane rotation of the first metatarsal. Methods: A total of 33 feet in 30 patients who had undergone Lapidus arthrodesis for the treatment of hallux abducto valgus deformity from 1 August 2015 to 31 December 2020 were identified. The median age of the cohort was 55.4 years (range, 33–78 years), 23 were female (76.7%), three (10%) underwent bilateral Lapidus arthrodesis, and the median duration of follow-up was 15.9 months (range, 5–72 months). Results: The median (minimum, maximum) preoperative first intermetatarsal angle was 16° (13°, 28°), and at final follow-up it was 5° (0°, 6°) (p < 0.001). The median (minimum, maximum) preoperative hallux abductus angle was 37° (26°, 51°), and at final follow-up it was 8.5° (0°, 22.5°) (p < 0.001). The median (minimum, maximum) preoperative tibial sesamoid position was 6 (4, 7), and at final follow-up it was 3 (2, 5) (p = 0.001). Conclusions: We found the radiographic first metatarsal lateral round sign to be ambiguous. Qualitative comparison of the results of this investigation with prior studies describing outcomes following Lapidus arthrodesis with focused frontal plane rotation of the first metatarsal suggests that similar outcomes can be achieved without employment of a decisive frontal plane rotation of the first metatarsal. Our findings lead us to believe that correction of substantial hallux abducto valgus deformities can be accomplished using the Lapidus procedure combined with lateral release of the first metatarsophalangeal joint without focused derotation of the first metatarsal. 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

Objectives: Flat feet is a very common deformity in children. Often, radiologic evaluation for children with flat feet is made. Although the measurement reliability of some angles in flat feet has been evaluated in the literature, none of them have been performed in the age range of 3-7 years, when the deformity is most common. Our aim is to evaluate the interobserver and intraobserver reliability of the 7 angles that are used for assessing flat feet. Methods: Radiologic angles were measured by four independent observers (two specialists and two residents) in two separate sessions on the foot radiographs of 50 children aged 3-7 years with clinically diagnosed flat feet in the appropriate position and intra-class correlation coefficient was evaluated. Thus, interobserver and intraobserver reliability was measured. Results: High reliability values were found in the AP talus - 1st metatarsal (APT1MT) angle and calcaneus inclination (Cl) angle, while the reliability was moderate in the other angles. Intraobserver reliability values tended to be higher than interobserver values, which is consistent with other studies. Conclusions: It is useful to keep in mind that the measurement reliability is moderate except for APT1MT and CI when angles are measured in this specific age group. No positive effect of experience on measurement reliability was found in our study. Full article

Flatfeet involve a collapse of the medial longitudinal arch, hindfoot valgus, and forefoot abduction. Flexible flatfoot is the most common type and can often be corrected with physiotherapy or orthotics. While some individuals remain asymptomatic, others develop symptoms for reasons that are not fully understood. This cross-sectional study compared plantar pressure distributions in 16 adults with asymptomatic and 16 with symptomatic flexible flatfeet (FPI-6 > 6; navicular drop > 5 mm), using a resistive-sensor-equipped pressure plate during walking and heel-strike running. During walking, symptomatic participants showed significantly higher total and peak forces at metatarsal 5 (p ≤ 0.003), and the midfoot (p ≤ 0.02146). The medial heel had significantly lower peak force (p = 0.00147), and metatarsal 4 showed higher peak force (p = 0.02539). Force ratios indicated a more lateralized pressure distribution in the symptomatic group. During heel-strike running, the symptomatic group exhibited higher total and peak forces at the fifth metatarsal, the midfoot, and the first metatarsal, with shorter time to peak force in the midfoot and the medial part of the heel. No significant ratio differences were found during running. Symptomatic individuals adopted a lateralized pressure distribution pattern, contrasting the traditional expectation of medial overload in flatfoot conditions. Full article

Background: The Lapidus procedure has become a cornerstone in the surgical management of hallux valgus, especially in cases with associated tarsometatarsal instability. This study investigated and compared the radiographic outcomes of three distinct Lapidus constructs, aiming to provide valuable insights into the optimal fusion configurations for achieving long-term stability improvement and maintaining the intermetatarsal angle (IMA) postoperatively. Methods: In this retrospective study, the objective was to assess and compare the outcomes of three different fusion constructs used in the Lapidus procedure: group 1, transverse screw fixation; group 2, metatarsal cuneiform screw fixation; and group 3, combined transverse and metatarsal cuneiform screw fixation. The study encompassed 32 feet: 11 in group 1, 8 in group 2, and 13 in group 3. The primary focus was to evaluate postoperative stability through radiographic imaging complemented by clinical assessments and an examination of complications. Statistical analyses were used to compare outcomes across the three fixation groups immediately, 3 months, 6 months, and 1 year postoperatively. Results: Radiographic assessments demonstrated successful fusion, and patients reported improvements in pain and function and overall satisfaction with the procedure. Complication rates were within an acceptable range. The IMA in all three groups exhibited a significant reduction postoperatively compared with preoperative measurements. Group 3 demonstrated a notably stronger initial reduction in the IMA compared with groups 1 and 2, and they maintained a statistically significantly more stable IMA value and exhibited a lower recurrence rate compared with the other two groups 1 year postoperatively. Conclusions: These findings endorse the use of Lapidus fusion with these three constructs, particularly with combined transverse and metatarsal cuneiform screw fixation, as a dependable and efficacious surgical approach in addressing hallux valgus with concomitant tarsometatarsal instability. Full article

This study aimed to establish normative in-shoe plantar foot temperature patterns across three static postures—lying, sitting, and standing—in healthy individuals, providing a clinically relevant baseline for interpreting in-shoe thermograms in diabetic or peripheral arterial disease (PAD) populations. A single-center prospective study included 20 healthy adults (40 limbs; 22–74 years) who underwent vascular and neurological screening prior to data collection. Plantar temperature was continuously recorded using Tarsos^® Smart Insoles with 21 embedded sensors per foot during three consecutive 10 min phases: supine, sitting, and standing. Data were analyzed for regional differences across the toes, metatarsals, arch, and heel using statistical and visual methods. Distinct posture-related temperature patterns were observed. The arch consistently exhibited the highest temperatures, while the toes remained cooler across all phases. Supine positioning resulted in relatively uniform temperature increases, whereas sitting and standing demonstrated more-stable but region-specific patterns, with slower rates of temperature change and more pronounced regional variation. Compared with barefoot thermography, the in-shoe condition showed greater heat retention and reduced evaporative cooling, highlighting the importance of context-specific baseline data. These findings demonstrate the influence of posture on plantar thermal distribution in the in-shoe environment and support the use of embedded monitoring systems for continuous assessment where surface thermography is not feasible. 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

Sentinel lymph node mapping is increasingly used in canine and feline oncology and often involves the combined use of visible dyes and fluorescent tracers. However, the effect of methylene blue on the fluorescence of indocyanine green during near-infrared imaging remains unclear. This explorative study aimed to quantitatively and qualitatively assess potential fluorescence quenching in solutions of methylene blue–indocyanine green at different ratios in three near-infrared imaging modalities (overlay, color map, contrast). Four solutions were prepared: 100%/0%, 75%/25%, 50%/50%, and 25%/75% indocyanine green/methylene blue. The fluorescence intensity of the four solutions was quantitatively measured in vitro using near-infrared imaging. Subsequently, four lymphographies, one for each solution, were performed from the metatarsal region of feline cadavers. Observers with varying levels of experience evaluated lymphographic images. Methylene blue caused a concentration-dependent reduction in fluorescence both at the quantitative evaluation and qualitative lymphography interpretation. Despite this reduction, fluorescence remained sufficient in cadavers for accurate identification of lymph nodes, and observer experience did not significantly affect interpretation, except for the color map mode. Because methylene blue-dominant solutions showed a greater quenching effect on indocyanine green fluorescence, clinicians should favor indocyanine green-dominant mixtures. This approach may preserve fluorescence performance, maintaining the surgical guidance benefits of methylene blue. Future confirmatory studies should include a substantially larger number of specimens to allow appropriate statistical comparisons and to better account for inter-individual variability. Full article

Background: The number of patients with rheumatoid arthritis (RA) undergoing forefoot arthroplasty has increased to better control the disease. Despite patients frequently expressing concerns regarding postoperative foot appearance and footwear-related expectations, no study has investigated postoperative changes in foot length and width in patients with RA. The aim of this study was to evaluate the effect of surgical procedures for rheumatoid forefoot deformities on variations in radiologically determined foot length and width. Methods: In total, 72 feet of 50 women and 3 men (average age: 66.7 years) underwent joint-preserving arthroplasty (n = 33) and arthrodesis of the first metatarsophalangeal joint with shortening osteotomy of the lesser metatarsals or resection arthroplasty of the lesser metatarsal heads (n = 39); procedures were carried out in our institute from August 2013 to February 2020. The mean disease duration was 23.5 years, and the average follow-up period was 17.5 months. Pre- and postoperative hallux valgus angle (HVA), intermetatarsal angle (IMA) of the first and second metatarsals (M1M2A), and IMA of the first and fifth metatarsals (M1M5A) were measured on weightbearing radiographs as well as foot length and width. We also evaluated the correlation between changes in radiographic parameters and variations in radiologically determined foot length and width. Results: Radiologically determined foot width changed significantly from 10.1 cm to 9.7 cm (p < 0.01), while no significant difference was found between pre- and postoperative radiologically determined foot length. HVA, M1M2A, and M1M5A were significantly improved after the surgery (p < 0.01, p < 0.01, and p < 0.01, respectively). A significant negative correlation was found between the variation in radiologically determined foot length and changes in HVA (r = −0.29, p = 0.02) and M1M5A (r = −0.23, p < 0.05), while a significant positive correlation was found between the variation in the foot width and changes in HVA (r = 0.34, p < 0.01), M1M2A (r = 0.55, p < 0.01), and M1M5A (r = 0.45, p < 0.01). There were no significant differences between operative procedures regarding variation in radiologically determined foot length and width. Conclusions: Surgical procedure for rheumatoid forefoot deformity improved radiographic parameters and reduced radiographic foot width while maintaining foot length. Full article

Objectives: To provide a mechanism-oriented integration of clinical and biomechanical evidence regarding fixation failure in fifth metatarsal fractures, with particular emphasis on Jones and diaphyseal stress fractures, and to clarify the mechanical determinants that influence construct performance under physiologic gait-related loading. Methods: A narrative, concept-driven review was conducted focusing on experimental biomechanical investigations and clinically relevant outcome studies addressing cyclic shear, bending, torsion, interfragmentary gap behavior, and loading direction. Special attention was given to studies employing advanced experimental models, including three-dimensional printed anatomical constructs combined with digital image correlation (DIC), to evaluate fixation strategies under simulated gait-phase loading conditions. Literature selection was guided by thematic relevance to construct mechanics and clinical fixation outcomes rather than systematic retrieval criteria. Results: Available evidence indicates that fixation constructs relying predominantly on interfragmentary compression demonstrate increased sensitivity to imperfect reduction, interfragmentary gaps, and multidirectional cyclic shear forces, particularly during midstance loading. Experimental models suggest that loading angle and gap size significantly influence stress concentration and failure patterns. Plate-based and hybrid constructs may provide improved resistance to cyclic bending and shear in specific experimental conditions, maintain stability in the presence of small fracture gaps, and distribute mechanical loads more uniformly across the fracture site. These biomechanical characteristics may help explain reported clinical patterns of delayed union, refracture, and hardware failure in high-demand patients or in cases with cortical compromise. Conclusions: Fixation failure in fifth metatarsal fractures appears to result from the interaction between fracture morphology, patient-specific loading demands, and construct biomechanics. Mechanism-based integration of biomechanical findings with clinical context may support individualized surgical decision-making. However, given the heterogeneity of available clinical data and the inherent limitations of experimental models, biomechanical insights should be interpreted as hypothesis-generating and complementary to clinical judgment rather than prescriptive guidance. Full article