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ABSTRACT Data regarding the outcome of canine rib chondrosarcoma is sparse and varied. While grade of tumour is associated with outcome for canine appendicular chondrosarcoma, the association of grade with outcome for canine rib chondrosarcoma is unclear. This study aimed to correlate the grade of canine rib chondrosarcoma with median survival time. Retrospectively, cases of primary rib chondrosarcoma were identified, and tumours were graded based on a 3‐tier adapted human grading scheme. Twenty‐two patients were included in the survival analysis. The median survival time was 1427 days (range: 27–3354 days). This was not significantly different for patients with grade I versus II versus III (p = 0.82), grade I–II versus III (p = 0.34), or grade I versus II–III (p = 0.49). No variables assessed including age, weight, tumour location (cranial vs. caudal thorax; left vs. right hemithorax), tumour location on rib (proximal, middle, and distal), radiographic appearance (lytic, proliferative, or mixed), elevated serum alkaline phosphatase activity, grade, grade specific histologic features (matrix production, architecture, pleomorphism, cellularity, necrosis, and total score), adjunct therapy post‐surgical excision, development of metastatic disease post‐surgery, or local recurrence post‐surgery were found to impact the risk of death due to chondrosarcoma. In this limited group of patients, the grading scheme reported here, and the other variables assessed did not appear to offer additional prognostic information. However, this data must be interpreted considering the small sample size and thus low statistical power. Additional studies are needed to determine the true impact of grade on outcome for canine rib chondrosarcomas. [ABSTRACT FROM AUTHOR]

Respiratory–swallowing coordination (RSC) is well established as an essential airway‐protective mechanism. Previous studies have used nasal airflow and/or kinematic rib cage and abdominal measures to assess respiration surrounding swallowing, meaning that the direct influence of oral respiration on RSC remains unknown. This study used a partitioned oronasal facemask to compare respiratory phase patterns measured using isolated nasal airflow with those measured using combined oronasal airflow during non‐ingestive and ingestive swallowing tasks. Twenty‐four healthy individuals with no respiratory or swallowing disorders were assessed at rest and during cued dry, 10 mL water, continuous drinking and cracker swallowing tasks. Respiratory phase patterns were determined for discrete swallows using the nasal and combined oronasal channels separately. There was variable agreement between respiratory phase patterns according to the nasal and oronasal channels across swallowing conditions. The frequency of exhale–swallow–exhale, inhale–swallow–exhale and exhale–swallow–inhale patterns increased by 2%–3% each with the addition of oral flow data to nasal data, whereas the prevalence of inhale–swallow–inhale and ambiguous patterns decreased. This suggests that estimates of respiratory phase patterns are altered minimally by inclusion of oral respiratory estimates in a healthy sample. There were several additional findings of note, including lower within‐participant, within‐session trial consistency (test–retest reliability) than expected, suggesting high variability in respiratory phase patterns across trials. Additionally, data showed evidence of swallowing non‐respiratory flow at the beginning and end of the respiratory–swallowing pause, moving in both inward and outward directions, potentially expanding current understanding of swallowing non‐respiratory flow. Further in‐depth physiological investigations are required to improve understanding of these findings. What is the central question of this study?What is the impact of mouth breathing on the frequency of respiratory phase patterns for respiratory–swallowing coordination?What is the main finding and its importance?Added oral flow appeared to alter respiratory phase patterns minimally in healthy individuals. This was probably attributed to increased clarity of the respiratory flow signal, aiding interpretation of respiratory data. This suggests that mouth breathing might impact measurement of respiratory phase patterns. These findings might have implications for the methods used to assess respiratory phase patterns and broader respiratory–swallowing coordination, particularly in patient populations prone to mouth breathing. [ABSTRACT FROM AUTHOR]

Purpose: To report an adult case of cervical lung herniation involving the azygous lobe and to review the literature. Methods: A trauma patient was incidentally found to have a cervical lung herniation involving the azygous lobe. We reviewed the literature on cervical lung herniation, described techniques used to diagnose and evaluate cervical lung herniations and summarized management options. Results: Cervical lung herniation results in a defect in Sibson's fascia allowing the apical lung to protrude above the thoracic inlet. In the adult population, these are commonly seen after trauma or surgical intervention, but congenital forms have also been described in the pediatric population. Apical herniation of the lung can cause symptoms due to mass effect on the esophagus or trachea. We report an adult case of cervical lung herniation involving the azygous lobe. Conclusion: Cervical lung herniation is a relatively rare entity compared to lung herniation through the rib cage. Knowledge of this entity is essential to properly evaluate trauma patients and to diagnose patients who have symptoms of cough, dysphagia or a bulging neck mass. [ABSTRACT FROM AUTHOR]

We present a technique for the detection of vertebrate skeletons buried at shallow depths through the use of a ground-penetrating radar (GPR). The technique is based on the acquisition of high-resolution data by medium-to-high frequency GPR antennas and the analysis of the radar profiles by a new forward modelling method that is applied on a set of representative traces. This approach allows us to obtain synthetic traces that can be used to build detailed reflectivity diagrams that plot spikes with a distinct amplitude and polarity for each reflector in the ground. The method was tested in a controlled experiment performed at the top of Cerro Los Quesos, one of the most fossiliferous localities in the Ica Desert of Peru. We acquired GPR data at the location of a partially buried fossil skeleton of a large whale and analyzed the reflections associated with the bones using the new technique, determining the possible signature of vertebrae, ribs, the cranium (including the rostrum), and mandibles. Our results show that the technique is effective in the mapping of buried structures, particularly in the detection of tiny features, even below the classical (Ricker and Rayleigh) estimates of the vertical resolution of the antenna in civil engineering and forensic applications. [ABSTRACT FROM AUTHOR]

Chronic recurrent multifocal osteomyelitis (CRMO) or chronic nonbacterial osteitis is a sterile autoinflammatory disease of bone in children that can mimic infectious osteomyelitis and osteosarcoma. Early diagnosis, treatment, and long-term follow-up of CRMO are essential. We describe a 10-year-old boy who presented with 15 days of left ankle bone more than joint pain, swelling, and limp. Plain radiographs and magnetic resonance imaging scans were nondiagnostic of osteomyelitis and tibial irrigation and biopsy were negative for infection and malignancy. Four years later, he again presented with similar pain in his right ankle. Repeat bone biopsy noted reactive bone changes and bone culture was sterile. Whole-body magnetic resonance imaging revealed multiple enhancing lesions in the long bones of bilateral lower extremities, spine, and sternum. He was diagnosed with CRMO, and treatment with celecoxib and subsequently pamidronate, infliximab, and methotrexate were initiated. After 6 months of treatment, the patient's gait and pain improved, and 2 years later, his CRMO was in clinical and radiologic remission. Of note, he developed palmoplantar pustular psoriasis, commonly seen in CRMO, that was not determined to be from tumor necrosis factor inhibition. [ABSTRACT FROM AUTHOR]

Variants in more than 60 different genes, most of which code for podocyte‐related proteins, have been found to be associated with monogenic forms of nephrotic syndrome (NS). Biallelic variants in DAAM2, a member of the formin family, were recently identified to cause autosomal recessive (AR) NS type 24 in four unrelated families with steroid‐resistant nephrotic syndrome (SRNS). This case report represents only the fifth reported family of DAAM2‐associated NS and the first from India, with two sibs who presented with a complex phenotype characterized by steroid‐resistant nephrotic syndrome, short stature, dysmorphic facial features, deep‐set toenails, myopia, increased thickness of the calvarium of the skull, and sloping ribs. Both sibs were found to have a homozygous likely pathogenic nonsense variant c.196C>T (p.Arg66Ter; NM_001201427.2) in exon 3 of the DAAM2 gene through whole exome sequencing. The dysmorphic features could possibly be part of the DAAM2‐related phenotype which has hitherto not been reported or could represent a blended phenotype, with the extrarenal manifestations resulting from a yet to be identified coexisting genetic condition. [ABSTRACT FROM AUTHOR]

Background: Stress injuries are often missed secondary to their insidious onset, milder symptoms, and subtle or initially absent findings when imaged. Main Body: This review aims to provide strategies for evaluating and treating upper extremity stress fractures. This article outlines the classic presentation of each fracture, the ages during which these injuries often occur, the relevant anatomy and biomechanics, and the mechanism of each injury. Diagnostic imaging and management principles are also discussed, including the use of conservative versus surgical management techniques. Short Conclusion: Upper extremity stress fractures are often mild injuries that resolve with conservative management but can lead to more serious consequences if ignored. Given their increasing incidence, familiarity with diagnosis and management of these injuries is becoming increasingly pertinent. Key Points: Stress injuries are often missed secondary to their insidious onset, milder symptoms, and subtle or initially absent findings when imaged. This review aims to provide strategies for evaluating and treating upper extremity stress fractures. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we present the case of a dog diagnosed with a large thoracic wall extraskeletal osteosarcoma, which was successfully treated through chest wall reconstruction using a titanium mesh. This approach involved the en bloc resection of multiple ribs and the secure placement of a titanium mesh to reconstruct the chest wall. The dog showed significant improvement post-surgery, with no signs of disease recurrence or metastasis at the 8-month follow-up. This case highlights the effectiveness of titanium mesh in providing structural support and promoting recovery in dogs undergoing extensive chest wall resections due to large tumors. A 6-year-old castrated male mixed dog presented with a rapidly growing mass at the right chest wall two weeks after initial detection. A mesenchymal origin of the malignancy was suspected based on fine-needle aspiration. Computed tomography (CT) revealed that the mass originated from the right chest wall and protruded externally (6.74 × 5.51 × 4.13 cm3) and internally (1.82 × 1.69 × 1.50 cm3). The patient revisited the hospital because of breathing difficulties. Radiography confirmed pleural effusion, and ultrasonography-guided thoracocentesis was performed. The effusion was hemorrhagic, and microscopic evaluation showed no malignant cells. Before surgery, CT without anesthesia was performed to evaluate the status of the patient. The 7–10th ribs were en bloc resected at a 3-cm margin dorsally and ventrally, and two ribs cranially and caudally from the mass. After recovering the collapsed right middle lobe of the lung due to compression from the internal mass with positive-pressure ventilation, a 3D-printed bone model contoured titanium mesh was tied to each covering rib and surrounding muscles using 2-0 blue nylon and closed routinely. The thoracic cavity was successfully reconstructed, and no flail chest was observed. The patient was histo-pathologically diagnosed with extraskeletal osteosarcoma. A CT scan performed 8 months after surgery showed no evident recurrence, metastasis, or implant failure. This is the first case report of chest wall reconstruction using titanium mesh in a dog. The use of a titanium mesh allows for the reconstruction of extensive chest wall defects, regardless of location, without major postoperative complications. [ABSTRACT FROM AUTHOR]

This report describes two similar cases in which the distal forearm was compressed between the rib cage and floor for a prolonged period owing to immobility, resulting in severe compartment syndrome and extensive penetrating necrosis in the forearm. The cases were a 59-year-old man with cervical spondylolisthesis and a 65-year-old man suspected of having Parkinson's disease. A distinctive necrotic pattern characterized by necrosis in the volar and dorsal compartments, preservation of the lateral compartment, and retention of the radial artery was commonly observed in both cases. Despite the anticipated nonfunctional outcome of the salvaged limb, a two-lobed free latissimus dorsi musculocutaneous flap transfer with interposition of the thoracodorsal nerve in the median nerve defect was performed in both cases. Although the salvaged limbs were nonfunctional, the patients were able to use it for activities such as getting up and other daily tasks. [ABSTRACT FROM AUTHOR]

Mummification of corpses with partial skeletonization is not an uncommon occurrence in daily forensic work. Cooperation between different forensic fields is important in these cases in terms of obtaining the most accurate and forensically relevant results, especially when child abuse and neglect is suspected. In Central Europe, up to 21% of children are exposed to physical and psychological harm, which is mostly perpetrated by family members. This report describes a case of subadult female mummified remains in which interdisciplinary forensic pathology, forensic anthropology, and entomology input was needed to obtain legally relevant results. Entomological analysis of the fly and beetle species present served primarily to estimate the postmortem interval. External examination confirmed advanced postmortem decomposition of the body. The anthropological findings based on radiographs and analysis of selected bones confirmed various antemortem fractures and post-traumatic changes involving the ribs, the distal portion of the humerus, the nasal bones, and the anterior portions of the maxilla and mandible. Furthermore, non-specific findings of growth arrest (Harris) lines in the distal metaphysis of the right tibia indicated growth retardation and, overall, child neglect. The autopsy findings confirmed subdural blood coagulum, part of which formed a clearly moulded plaster mass that had originally been attached to the cranial vault up to the internal lamina. The findings indicated a post-traumatic condition as the underlying cause of death in this child. Interdisciplinary forensic analyses confirmed that the child had been repeatedly exposed to violent assaults throughout her lifetime. Key points If mummified remains with partial skeletonization of a subadult are found, collaboration among forensic experts is required In this case, dried subdural blood coagulum indicated post-traumatic, non-spontaneous subdural haemorrhage Periosteal reaction present on the facial bones and distal portion of the humerus was a suspicious finding Analyses of female subadult remains based on an interdisciplinary approach revealed a syndrome of child abuse and neglect [ABSTRACT FROM AUTHOR]

Background: For procedural education, the shift from the traditional apprenticeship model to simulation-based mastery has become increasingly accepted as the gold standard and has underscored the importance of high-fidelity, cost-effective training options. However, cost-effective pleural procedure simulators providing both realistic haptic feedback and ultrasound compatibility are lacking. Objective: We aimed to create a pleural procedure simulator with characteristics of human tissue, at low cost and with ultrasound compatibility. Methods: This work used design-based research principles and a collaborative rapid iteration approach in collaboration with the University of California, San Francisco, Makers Lab and design-based researchers at the University of California, Berkeley, which led to the creation of a three-dimensionally printed pleural procedure simulator. Results: The needs assessment indicated significant discomfort with pleural procedures and a request for more accessible simulation opportunities. Iterative prototyping resulted in a three-dimensionally printed rib cage and a series of innovations in the fluid pocket and skin layers to provide realistic tactile feedback and ultrasound imaging compatibility. The final model costs significantly less than commercial simulators, with durable components and replaceable parts that can be reused multiple times. Conclusion: The development of a low-cost, high-fidelity pleural procedure simulator addresses the current limitations of commercially available pleural simulators. By integrating three-dimensional printing technology and easily accessible materials, we were able to produce a simulator that closely replicates the feel of human tissue, allows ultrasound use, and is adaptable for different patient anatomies and clinical scenarios. This novel simulator is a scalable solution to elevate the standard of procedural education and ultimately positively affect patient care. [ABSTRACT FROM AUTHOR]

Background and aims - Euodia frauenfeldii has the characteristic 'semi-circular' or 'crescent-shaped' valves found in most species of Euodia, but as it also has a pair of conspicuous transapical costae, it was later transferred to Eunotogramma. Examination of the structure of its valves and girdle has led to a reassessment of its taxonomic position. Material and methods - We discuss various aspects of terminology used for the parts of the valve, their abbreviations used throughout the literature and provide a detailed taxonomic background to both Euodia and Eunotogramma. Key results - A new genus, Moralesonia is described and its relationships discussed. [ABSTRACT FROM AUTHOR]

Radiologists often inspect hundreds of two-dimensional computed-tomography (CT) images to accurately locate lesions and make diagnoses, by classifying and labeling the ribs. However, this task is repetitive and time consuming. To effectively address this problem, we propose a multi-axial rib segmentation and sequential labeling (MARSS) method. First, we slice the CT volume into sagittal, frontal, and transverse planes for segmentation. The segmentation masks generated for each plane are then reconstructed into a single 3D segmentation mask using binarization techniques. After separating the left and right rib volumes from the entire CT volume, we cluster the connected components identified as bones and sequentially assign labels to each rib. The segmentation and sequential labeling performance of this method outperformed existing methods by up to 4.2%. The proposed automatic rib sequential labeling method enhances the efficiency of radiologists. In addition, this method provides an extended opportunity for advancements not only in rib segmentation but also in bone-fracture detection and lesion-diagnosis research. [ABSTRACT FROM AUTHOR]

With the great development of the construction industry, prefabricated building components have been greatly developed. To study the compressive performance of the new wallboard, the axial compression performance test of six full-scale new lattice wallboards was carried out in this paper. The failure mode, axial pressure-displacement relationship curve, axial compression bearing capacity, and axial pressure-strain relationship of the wallboard were obtained through the experiments. This reveals the influence of the thickness of the concrete surface and the number of ribs on the performance of the wallboard. The test results show that the ultimate bearing capacity of the specimen increases with the increase of the thickness of the concrete surface layer with the same number of ribs. Specimen DW -30 increased by 4% over DW -20 and DW -50 increased by 41.6% over DW -30. The ultimate bearing capacity of the three-ribbed specimens was higher than that of the two-ribbed specimens for the same concrete face thickness, about 1.11 times that of the two-ribbed specimens. The concrete facing thickness and the number of ribs have a restraining effect on the deformation of the wallboard. Additionally, the calculation formula of axial bearing capacity of type latticed wallboard considering the influence of eccentric compression was proposed, which can provide a reference for engineering calculation. [ABSTRACT FROM AUTHOR]

Background: Accurate assessment of the bone supporting the implant is crucial. Early detection of bone defects around the implant can prevent the loss of bone support that ultimately leads to the loss of the implant. Therefore, the purpose of this study is to check the accuracy of CBCT in detecting peri-implant fenestrations around the implant. Materials & methods: In this laboratory study, healthy beef ribs were used. The ribs were divided into three groups of 12 (control group, 1–2 mm fenestration group, and 2–3 mm fenestration group). The blocks were cut to a length of 20 mm and 36 osteotomies with dimensions of 4 × 12 mm were made by the periodontist in order to place the implant in these bone blocks. Then the titanium implant was placed in the holes and the initial scan was performed with CBCT. In the second group, fenestration-like lesions were created on the same buccal side at a distance of 10 mm from the crest with a diameter of 1–2 mm and in the third group with a diameter of 2–3 mm, and the CBCT scan was performed again with the same parameters. Two radiologists evaluated the images twice for the presence and absence of fenestration. Results: There was no statistically significant difference between direct measurements and CBCT in the fenestration group of 1–2 mm (p < 0.05), but there was a significant difference between direct measurements and CBCT in the fenestration group of 2–3 mm and underestimation was observed in CBCT measurements. Conclusion: The findings of this study showed that CBCT radiography has a higher accuracy in measuring the fenestration around the implant with a smaller diameter and has an acceptable diagnostic value in detecting bone loss around the implant. [ABSTRACT FROM AUTHOR]

Purpose: In the existing literature, various insertion variations and classifications for the Pectoralis Minor (PMi) muscle have been reported. However, there is limited information on inferior origin variations of the PMi muscles and a certain classification is lacking. Case Presentation: During routine cadaver dissection of an adult male, variations in the origin of the bilateral PMi muscles were identified. Morphometric measurements of the PMi were conducted using ImageJ software, and the unusual origin patterns of the PMi were categorized into specific types. The PMi muscle demonstrated a bilateral variations. On the right side, the PMi displays a bifid structure comprising medial and lateral fibers. The left PMi originate from the superolateral margins of the 4th to 6th costae and terminate at the anterosuperior surface of the coracoid process. The length of the right medial fiber before merging was 5.67 ± 0.04 cm, while that of the right lateral fiber was 6.68 ± 0.05 cm. The distance between the two fibers was measured as 0.43 cm, with a length of 3.33 ± 0.02 cm. The length and diameter of the muscle fibers extending to the 6th costa were 2.63 ± 0.01 cm and 0.46 cm, respectively. Conclusions: Potential variations in PMi arising from impairment during development may occasionally manifest as asymptomatic conditions or predispose individuals to shoulder impingement, rotator cuff dysfunction, shoulder-related disorders, and functional impairments. Therefore, careful attention to this variation is considered in surgical planning. [ABSTRACT FROM AUTHOR]

Kidney segmentation from abdominal computed tomography (CT) images is essential for computer-aided kidney diagnosis, pathology detection, and surgical planning. This paper introduces a kidney segmentation method for clinical contrast-enhanced CT images. First, it begins with shape-based preprocessing to remove the spine and ribs. Second, a novel clustering algorithm and an initial kidney selection strategy are utilized to locate the initial slices and contours. Finally, an adaptive narrow-band approach based on active contours is developed, followed by a clustering postprocessing to address issues with concave parts. Experimental results demonstrate the high segmentation performance of the proposed method, achieving a Dice Similarity Coefficient of 97.4 ± 1.0% and an Average Symmetric Surface Distance of 0.5 ± 0.2 mm across twenty sequences. Notably, this method eliminates the need for manually setting initial contours and can handle intensity inhomogeneity and varying kidney shapes without extensive training or statistical modeling. [ABSTRACT FROM AUTHOR]

Background: Gastroliths are stones of uncertain purpose that are commonly found inside the rib cages of plesiosaur fossils worldwide. Gastroliths from four Alberta (Canada) plesiosaurs were studied to determine both their shapes and masses, and their mass fractions relative to body mass. One animal's set of gastroliths was 100% complete and fully visible, but the others showed varying degrees of loss, damage or obscuration, so estimations of their original states were needed. Methods: The studied animals were: Albertonectes vanderveldei, Fluvionectes sloanae, Nichollssaura borealis and Wapuskanectes betsynichollsae. The animals come from three different palaeoenvironments: open marine, near shore marine, and fluvial. Gastrolith shapes were classified as either xiphoid, cylindrical, discoidal or spherical based on observed and/or estimated dimensions. Although not all methods could be applied in all cases, gastrolith shapes and masses were estimated four different ways: (1) direct measurement and weighing of a subset and predicting the properties of the remaining obscured and hidden stones; (2) measuring triaxial ellipsoid dimensions of free stones to calculate volumes and multiplying by the mass density of chert; (3) measuring two visible triaxial dimensions of embedded stones, estimating the hidden third dimension three different ways, and then determining volumes and masses by calculation; and (4) predicting the density and mass of a densely packed cluster of small gastroliths using geometrical arguments. Results: Total gastrolith mass never exceeded 0.2% of body mass in any plesiosaur, and is consistent with the idea that the amounts of gastroliths recovered with plesiosaurs would be ineffective as ballast. The largest plesiosaur in the sample had the largest single gastrolith and total gastrolith mass increases with body size. The shape characteristics of the gastroliths were different for different environments, but compositionally they are dominated by black cherts. A possible common source for the gastroliths was identified for the two geographically close and near-contemporanous Nichollssaura and Wapuskanectes. [ABSTRACT FROM AUTHOR]

This study deals with base pressure management in a duct for various values of the Mach number (M), namely, Mach number corresponding to sonic and four supersonic conditions. In addition to the Mach number, the nozzle pressure ratio (NPR), the area ratio, the rib dimension, and the duct length are influential parameters. The following specific values are examined at M = 1, 1.36, 1.64, and 2, and NPRs between 1.5 and 10. The base pressure is determined by positioning ribs of varying heights at predetermined intervals throughout the length of the square duct. When the level of expansion is varied, it is seen that the base pressure initially drops for overexpanded flows and increases for under-expanded flows. When ribs are present, the flow field in the duct and pressure inside the duct fluctuate as the base pressure rises. Under-expanded flows can achieve a base pressure value that is suitably high without experiencing excessive changes in the duct flow in terms of static pressure if a rib height around 10% of the duct height close to the nozzle exit is considered. Rectangular rib passive control does not negatively affect the duct's flow field. [ABSTRACT FROM AUTHOR]

Background: Cerebro-costo-mandibular syndrome (CCMS) is a rare congenital syndrome consisting of the main features of micrognathia and posterior rib gaps. Due to multiple abnormalities, patients almost have difficulty breathing with upper airway obstruction, decreased thoracic capacity, spina bifida, and scoliosis. Case presentation: We describe a case of a late preterm neonate boy presenting with low Apgar, respiratory distress, and complicated orofacial anomalies that had a poor outcome. His radiographic findings showed mandibular hypoplasia (micrognathia), chest deformity, multiple posterior rib gap defects, and abnormal costotransverse articulation. Based on physical examination and radiologic findings, the diagnosis of CCMS confirmed for the patient. Conclusion: Physicians should always consider the diagnosis of CCMS in all infants with micrognathia and rib-gap defects. These infants need careful respiratory function monitoring. Early airway management improves growth and development. In addition, their physical and psychological development should be assessed regularly. [ABSTRACT FROM AUTHOR]

Background: It is aimed to compare the block onset times and performance features of costoclavicular techniques (medial and lateral approach) versus lateral sagittal technique. Methods: Patients were randomized into three groups. For costoclavicular techniques, ultrasound probe was placed parallel to clavicle obtaining nerve cords, axillary artery and axillary vein visual from lateral-to-medial, respectively. The block needle was advanced from lateral (Group CLB) or medial (Group CMB) to perform costoclavicular block. For lateral sagittal technique (Group LSB), ultrasound probe was placed sagittal and perpendicular below the coracoid process to obtain sagittal artery image with the cords around. Total 20 ml of 0.5% bupivacaine and 10 ml of 2% lidocaine were deposited for all groups. Sensory and motor block onset times, block performance properties, complications, and patient/surgeon satisfactions were investigated. Results: Among 56 patients, the primary outcome, sensory block onset time was shorter in Group CLB than Group CMB and Group LSB (10 [5–15], 10 [10–20], and 15 [10–15] minutes, respectively, p < 0.05). Motor block onset was also fastest in Group CLB (15 [10–20] mins for CLB, 20 [15–20] mins for LSB, and 22.5 [15–25] mins for CMB, p = 0.004). Block performance properties did not differ between the groups. The only complication observed was vascular puncture with an incidence of 28% in Group CMB. Conclusions: Lateral approach costoclavicular technique provides fastest block onset than the other techniques. Considering the success and safety profile, this technique stands as a good alternative in clinical practice. Trial registration: This study is prospectively registered to clinicaltrials.gov on 20/02/2022 (NCT05260736). [ABSTRACT FROM AUTHOR]

Currently, only birds have a pneumatic system, but in the past, this was common among several ornithodirans. Within Titanosauria, it was the saltasaurines that showed a high degree of postcranial pneumaticity. The objective of this work is analysing the extent of postcranial pneumaticity in saltasaurines and compare it with other derived titanosaurs. To carry out this work, presacral vertebrae, dorsal ribs, scapulae, coracoids and ilia of saltasaurines were analysed. The presacral vertebrae present a high degree of pneumatisation with a highly variable distribution of foramina, with some ‘foramina zones’, there is a homoplastic pattern of pneumaticity: presence of foramina connected to camellated tissue. With respect to the ilia, camellated tissue was recorded in all taxa. Instead, scapulae and coracoids, present camellated tissue in Saltasaurus and they cannot be pneumatised in Neuquensaurus. Comparing with other titanosaurs, we observe that there are ‘foramina zones’ for presacral and caudal vertebrae. It is also possible to establish that the pneumatisation of the dorsal ribs has a conservative pattern, not only in saltasaurines but also in the Saurischia clade, and the presence of pneumaticity in the ilia is frequent in the Lithostrotia and even outside, in rebbachisaurs. [ABSTRACT FROM AUTHOR]

In this paper, the free vibration of a sandwich plate with an anisogrid core and two face sheets reinforced with graphene platelets (GPLs) is investigated. A continuous approach is considered for the lattice core and the equivalent properties are calculated. Adopting the Halpin–Tsai micromechanics, the effective Young’s modulus of the nanocomposites/graphene platelets is extracted. Also, mass density and Poisson’s ratio are earned with the simple rule of mixtures. A quasi-3D theory is applied to model the kinematics of the sandwich plate with simply supported boundary conditions. Hamilton’s principle is implemented to obtain the equations of motion that are solved based on the Navier solution. The validity of the results of this study is confirmed by comparing the analytical results with those presented in other researches and also a finite element model. The effect of the parameters of the lattice core such as the width of ribs, the number of helical ribs in one direction, and the ratio of thickness of face sheets to core on the natural frequencies of the sandwich plate was investigated. Additionally, the impact of the pattern of graphene platelets and their weight fraction on the natural frequencies were investigated. The results show that by decreasing the ratio of the thickness of face sheets to the thickness of core and increasing the number of ribs and their width, the natural frequencies will decrease. Moreover, the patterns FG-V and FG-A have the highest and the lowest natural frequencies, respectively, among the other distribution of graphene platelets. [ABSTRACT FROM AUTHOR]

Simple Summary: Surface tracking based on optical cameras is often used to reduce the imaging dose while maintaining precision during stereotactic ablative body radiotherapy. A region of interest (ROI) on a patient's skin is selected and monitored using harmless visible light in real time. Relying on the correlation between the skin and lesion respiratory motion, this region of interest is used as a surrogate for the tumor respiratory motion. In this study, the thoracic and abdominal skin region is segmented into nine smaller regions. For each of them, the respiratory motion magnitude and its correlation with a small structure in the lower lung (representing a lung lesion) are measured. Using the data provided by this study, a clinician can make an informed decision about which ROI to track when treating lower lung lobe lesions. Image-guided radiotherapy supported by surface guidance can help to track lower lung lesions' respiratory motion while reducing a patient's exposure to ionizing radiation. However, it is not always clear how the skin's respiratory motion magnitude and its correlation with the lung lesion's respiratory motion vary between different skin regions of interest (ROI). Four-dimensional computed tomography (4DCT) images provide information on both the skin and lung respiratory motion and are routinely acquired for the purpose of treatment planning in our institution. An analysis of 4DCT images for 57 patients treated in our institution has been conducted to provide information on the respiratory motion magnitudes of nine skin ROIs of the torso, a tracking structure (TS) representing a lower lung lobe lesion, as well as the respiratory motion correlations between the nine ROIs and the TS. The effects of gender and the adipose tissue volume and distribution on these correlations and magnitudes have been analyzed. Significant differences between the ROIs in both the respiratory motion magnitudes and their correlations with the TS have been detected. An overall negative correlation between the ROI respiratory magnitudes and the adipose tissue has been detected for ROIs with rib cage support. A weak to moderate negative correlation between the adipose tissue volume and ROI-to-TS respiratory correlations has been detected for upper thorax ROIs. The respiratory magnitudes in regions without rib support tend to be larger for men than for women, but no differences in the ROI-to-TS correlation between sexes have been detected. The described findings should be considered when choosing skin surrogates for lower lung lesion motion management. [ABSTRACT FROM AUTHOR]

An interosseous ganglion cyst is a very rare entity, found mostly in skeletally mature patients, particularly in long bones such as the tibia and femur. However, we are the first to report here an unusual case of interosseous ganglion cyst of the upper ribs in a young female patient, which she had an unpredicted presentation of cough and hemoptysis and a large painful lump over the anterior left upper chest. The radiological and pathological workup confirmed the presence of a benign interosseous ganglion cyst arising from the left first rib, invading the second rib and the apex of the left lung. The patient has been treated successfully by surgical resection of this rib cyst. However, we could not find any reported cases in the current literature of an interosseous ganglion cyst pathology arising in the ribs with a similar presentation of cough and hemoptysis. [ABSTRACT FROM AUTHOR]

Introduction: Mulligan therapy includes Sustained Natural Apophyseal Glides (SNAGs) and Mobilisation With Movement (MWM), which can be applied for spinal pain and Range of Motion (ROM). It helps to stretch the structures on the convex side of the offending movement and opens the intervertebral foramen. Pulmonary Function Test (PFT) is an important diagnostic test that helps guide decisions for management. Normal chest expansion is crucial for respiratory system function and tissue oxygenation. The contraction of external intercostal muscles moves the ribs upwards and outwards, causing the rib cage to expand, which increases the volume of the thoracic cavity. After the age of 25 years, normal pulmonary function begins to decline. Inappropriate posture leads to reduced thoracic cage mobility, thereby decreasing chest expansion. Thoracic SNAGs and MWM help stretch the structures, which will aid in chest expansion. Aim: To determine the effect of Mulligan therapy on pulmonary function and chest expansion in healthy individuals. Materials and Methods: A quasi-experimental study was conducted at Ramaiah Hospitals in Bengaluru, Karnataka, India over an 11-month period between July 2021 and June 2022. Based on the inclusion criteria, 103 participants were included, and Mulligan therapy was performed. Pre- and post-PFT and chest expansion measurements were taken and analysed using Student’s t-test. Results: The results showed a statistically significant difference in chest expansion at all three levels (p<0.001) and Forced Expiratory Volume (FEV1) in the first second/Forced Vital Capacity (FVC) (p=0.04), Peak Expiratory Flow (PEF) (p=0.03), Forced Inhibitory Volume in the first second (FIV1) (p=0.01), and FIV1/FIVC (p=0.03) values in the PFTs. Conclusion: Chest expansion and FEV1/FVC, PEF, FIV1, and FIV1/FIVC show a significant change post thoracic SNAGs, intercostal MWM, costochondral, and costovertebral MWM. However, no significant changes have been observed in the other parameters of pulmonary function. [ABSTRACT FROM AUTHOR]

Up to now, there have been no publication standardizing the digital reconstruction of the modern human ribcage from commingled costo‐vertebral material. Consequently, we designed a validated protocol based on anatomical features observed in the literature and the CT scanned ribcages of 10 adult European individuals. After quantifying the shape of these ribcages using 3D geometric morphometrics, we split each vertebra and rib within their corresponding (semi)landmarks. Subsequently, individual bones + (semi)landmarks were imported to LhpFusionBox, commingled and 3D reconstructed. To validate the accuracy of the protocol, we first reconstructed a randomly chosen ribcage three times and then compared these reconstructions to the rest of the sample. Since these reconstructions were closer to their original counterpart than to the others, the remaining sample was reconstructed once. Next, we tested the intra‐observer error during reconstructing using the Procrustes distances among the original ribcages and the reconstructions. We observed that first each ribcage reconstruction was clustered to its original counterpart and second there was a learning curve showing an improvement in the reconstruction process over time. Subsequently, we explored general size and shape differences among the original and reconstructed ribcages through a study of centroid size and a permutation test on the Procrustes distances (10,000 permutations), respectively. Specific shape differences between both groups were further examined through a principal component analysis in shape space. None of these analyses found statistical differences between the original and reconstructed ribcages (p > 0.05). Eventually, we extracted the mean shapes of the original ribcages and the reconstructions in order to visualize potential deviations caused by the anatomical considerations of the researcher. These results demonstrate that the protocol is accurate enough to be used when reconstructing a disarticulated human ribcage. [ABSTRACT FROM AUTHOR]

Introduction and aim. Pectus excavatum (PE) is a chest wall deformity characterized by a collapse of the rib cage. The Nuss procedure, originally intended for pediatric patients, is now also used in adults. The main aim of this study is to investigate whether the Nuss procedure can also lead to successful results in adult patients, although it is a widely used treatment method in pediatric patients. Material and methods. Data from 90 patients (October 2008-May 2020) included age, gender, preoperative findings, Haller index, operative details, and postoperative outcomes. The groups were divided into pediatric (<18 years) and adult (=18 years) patients. Mann-Whitney U and chi-square tests were used to assess group differences. Results. The adult group had a significantly higher bar length and preoperative complaints rate (p<0.05). No significant differences were found for other parameters (p>0.05). Conclusion. The Nuss procedure is safe and effective in both pediatric and adult PE patients. Age and preoperative symptoms influence surgical planning and outcomes, emphasizing their importance for treatment strategies. [ABSTRACT FROM AUTHOR]

This article provides information on the radiographic imaging of thoracic lymph nodes in dogs. It highlights the importance of understanding the locations and drainage patterns of these lymph nodes for accurate interpretation of thoracic radiographs and differential diagnoses. The article specifically focuses on the sternal, mediastinal, and tracheobronchial lymph nodes, discussing their normal appearance, potential causes of enlargement, and diagnostic considerations. It also mentions that lymphadenomegaly in adult dogs is often associated with neoplastic or inflammatory conditions, while antigenic stimulation and immune system development are additional considerations for young animals. The text emphasizes the significance of understanding the lymphatic system in dogs and specifically focuses on the tracheobronchial lymph nodes, which are commonly affected by neoplasia and infections. This knowledge can assist veterinarians in diagnosing and selecting appropriate testing for dogs with thoracic lymphadenomegaly. [Extracted from the article]

The article focuses on a rare case of acute lymphoblastic leukemia (ALL) in a pediatric patient presenting with hypercalcemia and lytic lesions, which can be diagnostically challenging. Topics include the association of these symptoms with higher-risk leukemias and the need for further research to understand this relationship better.

The tissue‐specific heart decellularized extracellular matrix (hdECM) demonstrates a variety of therapeutic advantages, including fibrosis reduction and angiogenesis. Consequently, recent research for myocardial infarction (MI) therapy has utilized hdECM with various delivery techniques, such as injection or patch implantation. In this study, a novel approach for hdECM delivery using a wet adhesive paintable hydrogel is proposed. The hdECM‐containing paintable hydrogel (pdHA_t) is simply applied, with no theoretical limit to the size or shape, making it highly beneficial for scale‐up. Additionally, pdHA_t exhibits robust adhesion to the epicardium, with a minimal swelling ratio and sufficient adhesion strength for MI treatment when applied to the rat MI model. Moreover, the adhesiveness of pdHA_t can be easily washed off to prevent undesired adhesion with nearby organs, such as the rib cages and lungs, which can result in stenosis. During the 28 days of in vivo analysis, the pdHA_t not only facilitates functional regeneration by reducing ventricular wall thinning but also promotes neo‐vascularization in the MI region. In conclusion, the pdHA_t presents a promising strategy for MI treatment and cardiac tissue regeneration, offering the potential for improved patient outcomes and enhanced cardiac function post‐MI. [ABSTRACT FROM AUTHOR]

The dolphin (Tursiops truncatus) is the most studied and most common species of cetacean in captivity. In this study, the size results obtained were the ribs and scapula. The first measure is a difference from the proximal to the distal end between the literature and this study. the second and third sizes have long, short, and longer proximal to distal differences. The fourth, fifth and sixth sizes show that the bones of T.truncatus are smaller than those of the Numataphocoena yamashitai species and the seventh size shows that the differences between T.truncatus and the Numataphocoena yamashitai species are several short and long costae. For the scapula, the dimensions of the first and second bones are larger than the present study species T.truncatus and Numataphocoena yamashitai. The sizes of the three results from this study are almost the same as the species Numataphocoena yamashitai except for the species Prosqualodon marplesi, which is larger than this study and research in California. The fourth size, which is 49.0 mm from head to tuberculum, is larger than the species T.truncatus and Numataphocoena yamashitai studied. The fifth size, the diameter of the rib head of this research species is smaller than the species Numataphocoena yamashitai and Prosqualodon marplesi, both of which are smaller than T.truncatus, and some of these differences are caused by food, habitat and environmental conditions. [ABSTRACT FROM AUTHOR]

There is a need to fully understand intra‐skeletal variability within different populations to develop and improve age‐at‐death estimation methods. This study evaluates age‐related histomorphometric changes in three different bones intra‐individually in a modern Australian sample. Four female and 13 male elderly Australian adult donors (67–93 years) were examined for osteon population density (OPD), osteon area (On.Ar), and Haversian canal area (H.Ar) of secondary osteons to compare between femora, ribs, and humeri and assess against age. In the pooled sex sample, no statistically significant correlations were observed between age and each histological variable. In the males, OPD of the femur increased significantly with age, as did porosity in the rib. In the male humeri, OPD increased moderately with age, while H.Ar was decreased moderately with age. Intra‐bone comparisons showed that males had significantly higher osteon counts in their ribs compared to their femora, while their ribs showed statistically significantly less porosity than their humeri. When bone size was accounted for, by adjusting the femur and humerus histology data by robusticity indices, histology values were found to be similar between bones within the same individual. This is despite the upper and lower limbs receiving different ranges and types of biomechanical load. Our findings demonstrate that bone size influences histomorphometry, and this could confound age‐at‐death estimations that have not been adjusted for robusticity. Future studies would benefit from examining bone histomorphometry within a larger sample size and incorporating bone robusticity measures into histology analyses. [ABSTRACT FROM AUTHOR]

Dinosaur skeletal material from the mid-Cretaceous of Canada is rare; however, the Cenomanian-aged Dunvegan Formation of northeastern British Columbia and northwestern Alberta is rich with ichnofossils attributed to nodosaurid ankylosaurs. A long bone (Hudson's Hope Museum specimen HH 2017.010.002) collected in 1993 from the Murray River of northeastern British Columbia is identified here as an ankylosaur femur. Femoral measurements of the bone plotted against femoral measurements of major dinosaur clades, combined with observations on femoral features, indicate that the bone belongs to an ankylosaur. The specimen is too damaged to assign to Nodosauridae or Ankylosauridae. HH 2017.010.002 represents the first limb bone material recovered from the Dunvegan Formation; previous ankylosaur material described from the Dunvegan Formation includes associated vertebrae and ribs from British Columbia and osteoderms from Alberta, as well as the presumed nodosaurid footprints Tetrapodosaurus borealis Sternberg, 1932. The Cenomanian is a time of great ecological change in North America, including the possible extirpation of ankylosaurid ankylosaurs. Fossils from the Dunvegan Formation can thus yield important insight into the responses of fauna to this major transition. [ABSTRACT FROM AUTHOR]

This study presents a novel approach to sternum prosthesis design, aiming to address the limitations of the current solutions by employing compliant mechanisms. The research focuses on developing a prosthetic design capable of generating lifting movements on ribs during breathing. First, a videogrammetry experimental test and virtual simulations were conducted to ascertain the vertical forces applied to each sternum joint. Subsequently, a compliant mechanism design was initiated, involving optimization and finite element analysis (FEM). A comprehensive kinematic performance analysis was performed to evaluate the prosthetic design. The results indicate that the obtained displacements of each rib closely align with those reported in the existing literature, demonstrating the effectiveness of the proposed solution. In conclusion, the developed sternum prosthesis exhibits the capability to recover approximately 56% of the ribs' natural movements, highlighting its potential as an innovative and promising solution in the field of chest prosthetics. [ABSTRACT FROM AUTHOR]

This document is a comment on a recent editorial about tidal volume (VT) in acute respiratory distress syndrome (ARDS). The authors raise two questions: whether driving pressure (ΔP) is an indicator of unsafe VT and its impact on outcomes, and what factors can influence compliance of the respiratory system and the interplay between VT and ΔP. They argue that statistical information is lost when dichotomizing VT and propose methods for addressing this issue. They also discuss the lung as a viscoelastic fluid and the importance of considering the mechanical characteristics of its container, the rib cage. The authors conclude that there are still many unanswered questions and call for approaching the problem from different perspectives to generate new hypotheses. [Extracted from the article]

Since the 19th century, underwater explosions have posed a significant threat to service members. While there have been attempts to establish injury criteria for the most vulnerable organs, namely the lungs, existing criteria are highly variable due to insufficient human data and the corresponding inability to understand the underlying injury mechanisms. This study presents an experimental characterization of isolated human lung dynamics during simulated exposure to underwater shock waves. We found that the large acoustic impedance at the surface of the lung severely attenuated transmission of the shock wave into the lungs. However, the shock wave initiated large bulk pressure-volume cycles that are distinct from the response of the solid organs under similar loading. These pressure-volume cycles are due to compression of the contained gas, which we modeled with the Rayleigh-Plesset equation. The extent of these lung dynamics was dependent on physical confinement, which in real underwater blast conditions is influenced by factors such as rib cage properties and donned equipment. Findings demonstrate a potential causal mechanism for implosion injuries, which has significant implications for the understanding of primary blast lung injury due to underwater blast exposures. [ABSTRACT FROM AUTHOR]

Simple Summary: Bone morphogenetic protein 6 (BMP-6) is known for its ability to stimulate bone and cartilage formation. The rib cage is an important skeletal structure; however, there has been limited research undertaken on the effects of the bmp6 gene on rib development. This study showcases the effective utilisation of CRISPR/Cas9 technology for the purpose of disrupting the bmp6 gene in silver carp, leading to the creation of chimeras in the P0 generation, marking the first instance of such an achievement. The chimeras exhibited complete viability, normal appearance, and partial intermuscular bones loss, with approximately 30% of them displaying rib bifurcation or bending. Subsequently, a transcriptome analysis on ribs of P0 chimeras and wild-type silver carp was conducted, leading to the identification of 934 genes exhibiting differential expression. A KEGG analysis revealed that the up-regulated genes such as tnfα, fos, and ctgf may facilitate the proliferation and differentiation of osteoclasts, whereas the down-regulation of genes such as tgfb2 and tgfbr1 may hinder the formation and specialisation of osteoblasts, ultimately resulting in rib abnormalities. This study presents novel findings on the impact of bmp6 gene deletion on the rib development of silver carp, while simultaneously investigating the previously unexplored molecular mechanisms underlying rib defects in fish. Bone morphogenetic protein 6 (BMP-6) is a constituent of the TGF-β superfamily, known for its ability to stimulate bone and cartilage formation. The investigation of bmp6's involvement in the formation of intermuscular bones in fish has garnered significant attention in recent years. The rib cage is an important skeletal structure that plays a protective function for internal organs in fish. However, there has been limited research conducted on the effects of the bmp6 gene on rib development. Silver carp is one of four major fish in China, favoured for its affordability and tender muscle. Nevertheless, the presence of numerous intermuscular bones in silver carp significantly hinders the advancement of its palatability and suitability for processing. This study showcases the effective utilisation of CRISPR/Cas9 technology for the purpose of disrupting the bmp6 gene in silver carp, leading to the creation of chimeras in the P0 generation, marking the first instance of such an achievement. The chimeras exhibited complete viability, normal appearance, and partial intermuscular bones loss, with approximately 30% of them displaying rib bifurcation or bending. Subsequently, a transcriptome analysis on ribs of P0 chimeras and wild-type silver carp was conducted, leading to the identification of 934 genes exhibiting differential expression, of which 483 were found to be up-regulated and 451 were found to be down-regulated. The results of the KEGG analysis revealed that the "NF-kappa B signalling pathway", "Hippo signalling pathway", "osteoclast differentiation", and "haematopoietic cell lineage" exhibited enrichment and displayed a significant correlation with bone development. The up-regulated genes such as tnfα, fos, and ctgf in pathways may facilitate the proliferation and differentiation of osteoclasts, whereas the down-regulation of genes such as tgfb2 and tgfbr1 in pathways may hinder the formation and specialisation of osteoblasts, ultimately resulting in rib abnormalities. This study presents novel findings on the impact of bmp6 gene deletion on the rib development of silver carp, while simultaneously investigating the previously unexplored molecular mechanisms underlying rib defects in fish. [ABSTRACT FROM AUTHOR]

Objective: There is a controversy in studies of circulating inflammatory proteins (CIPs) in association with osteoporosis (OP) and fractures, and it is unclear if these two conditions are causally related. This study used MR analyses to investigate the causal associations between 91 CIPs and OP and 9 types of fractures. Methods: Genetic variants data for CIPs, OP, and fractures were obtained from the publicly available genome-wide association studies (GWAS) database. We used inverse variance weighted (IVW) as the primary analysis, pleiotropy, and heterogeneity tests to analyze the validity and robustness of causality and reverse MR analysis to test for reverse causality. Results: The IVW results with Bonferroni correction indicated that CXCL11 (OR = 1.2049; 95% CI: 1.0308-1.4083; P = 0.0192) can increase the risk of OP; IL-4 (OR = 1.2877; 95% CI: 1.1003-1.5070; P = 0.0016), IL-7 (OR = 1.2572; 95% CI: 1.0401-1.5196; P = 0.0180), IL-15RA (OR = 1.1346; 95% CI: 1.0163-1.2668; P = 0.0246), IL-17C (OR = 1.1353; 95% CI: 1.0272-1.2547; P = 0.0129), CXCL10 (OR = 1.2479; 95% CI: 1.0832-1.4377; P = 0.0022), eotaxin/CCL11 (OR = 1.1552; 95% CI: 1.0525-1.2678; P = 0.0024), and FGF23 (OR = 1.9437; 95% CI: 1.1875- 3.1816; P = 0.0082) can increase the risk of fractures; whereas IL-10RB (OR = 0.9006; 95% CI: 0.8335-0.9730; P = 0.0080), CCL4 (OR = 0.9101; 95% CI: 0.8385-0.9878; P = 0.0242), MCP-3/CCL7 (OR = 0.8579; 95% CI: 0.7506-0.9806; P = 0.0246), IFN-g [shoulder and upper arm (OR = 0.7832; 95% CI: 0.6605-0.9287; P = 0.0049); rib(s), sternum and thoracic spine (OR = 0.7228; 95% CI: 0.5681-0.9197; P = 0.0083)], b-NGF (OR = 0.8384; 95% CI: 0.7473-0.9407; P = 0.0027), and SIRT2 (OR = 0.5167; 95% CI: 0.3296-0.8100; P = 0.0040) can decrease fractures risk. Conclusion: Mendelian randomization (MR) analyses indicated the causal associations between multiple genetically predicted CIPs and the risk of OP and fractures. [ABSTRACT FROM AUTHOR]

Chest x-ray images are one of the most commonly performed imaging tests, providing crucial clinical information about structures like the heart, lungs, ribs, bones, and blood vessels. In this context, image segmentation is a critical stage as it aims to separate significant parts of an image. However, manual image segmentation presents serious difficulties that can be tackled using deep learning-based methods, such as U-Net. Furthermore, attention mechanisms have attracted the interest of the machine-learning community and can bring improvements in medical image segmentation. This research aims to assess the impact of attention-based mechanisms for segmenting different organs in chest X-ray images, like heart, lungs, clavicles and ribs, over the well-known U-Net architecture as a baseline. We study five U-Net encoder variations, replacing the U-Net encoder with ResNet 18, 34 and 50, Swin Transformer and a simple residual structure comprised of a single ResNet-50 prior to each U-Net encoder layer. In the original U-Net, the skip layers are identity layers connecting each encoder block with its corresponding decoder one. Here, we replace these layers with different attention mechanisms: spatial attention, full spatial attention, double spatial attention, multiple spatial attention, spatial cross-attention and Swin spatial cross-attention. Each encoder variation and attention mechanism was evaluated from scratch and on a pre-trained scenario, independently for lungs, ribs, heart and clavicles. ResNet-UNet-18 achieves up to 0.96 and 0.53 of average overlapping with hand-segmented masks of lungs and clavicles, respectively. The best encoder for rib and heart segmentation was Residual U-Net, with 0.88 and 0.83 overlapping, respectively. Furthermore, for attention mechanisms, the most suitable were selected according to overlapping with hand-segmented masks as Spatial Attention U-Net for lungs (0.96), Three-Head Attention for ribs (0.88), Full Spatial Attention for the heart (0.82) and Spatial Cross-Attention for clavicles (0.54). Encoder variations and attention mechanism have a positive impact over a U-Net for segmentation of lungs, ribs, heart and clavicles from scratch, without transfer learning. Moreover, the encoder and the attention mechanism are not universal for segmenting different organs in chest X-ray images. While organs share the same backbone architecture (lungs and clavicles), the most appropriate attention mechanisms for each organ are all different, achieving up to 0.99 of overlapping in lung segmentation. [ABSTRACT FROM AUTHOR]