Yield and clinical impact of image-guided bone biopsy in osteomyelitis of the appendicular skeleton: a systematic review and meta-analysis.

OBJECTIVE: To assess the yield and clinical impact of image-guided bone biopsy for osteomyelitis of the appendicular skeleton. MATERIALS AND METHODS: A literature search of several databases was conducted from inception to August 2023. Eligible studies reported patients who underwent image-guided bone biopsy for investigation of osteomyelitis of the appendicular skeleton. The pooled proportions were analyzed using a random-effects model. This review was registered in PROSPERO (CRD42023466419). RESULTS: From 370 initial studies screened, eight met the eligibility criteria, with a total of 700 patients. The pooled technical success rate was 99.6% (95% CI: 0.992, 1.001; I2 = 0%). Positive bone cultures were pooled at 31.9% (95% CI: 0.222, 0.416; I2 = 87.83%) and negative cultures at 68.1% (95% CI: 0.584, 0.778; I2 = 87.83%). Methicillin-Sensitive Staphylococcus Aureus and Methicillin-Resistant Staphylococcus Aureus yield was 24.5% (95% CI: 0.096, 0.394; I2 = 90.98%) and 7.6% (95% CI: 0.031, 0.121; I2 = 34.42%) respectively. Group A Streptococcus yield was 7.0% (95% CI: 0.014, 0.127; I2 = 70.94%). Polymicrobial culture yield was 15.7% (95% CI: 0.018, 0.297; I2 = 88.90%). Post-procedural management change rate was 36.5% (95% CI: 0.225, 0.504; I2 = 92.39%). No complications were reported across studies. CONCLUSION: For patients under investigation of osteomyelitis of the appendicular skeleton, image-guided bone biopsy demonstrates a good rate of technical success. Additional studies may provide further support for the use of image-guided bone biopsy in this population. Image-guided bone biopsy results lead to change in antibiotics therapy in a portion of patients with suspected osteomyelitis suggesting its potential utility in select patients.

Tomosynthesis of the Appendicular Skeleton on a Twin Robotic X-ray System: A Cadaveric Fracture Study.

RATIONALE AND OBJECTIVES: Aiming to offset image quality limitations in radiographs due to superimposition, this study investigates the diagnostic potential of appendicular skeleton tomosynthesis. MATERIALS AND METHODS: Eight cadaveric extremities (four hands and feet) were examined employing the prototypical tomosynthesis mode of a twin robotic X-ray scanner. 12 protocols with varying sweep angles (10, 20 vs. 40°), frame rates (13 vs. 26 fps), and tube voltages (60 vs. 80 kV) were compared to radiographs. Four radiologists separately evaluated cortical and trabecular bone visualization and fracture patterns. Interreader reliability was assessed based on the intraclass correlation coefficient (ICC). RESULTS: Radiation dose in radiography was 0.59 ± 0.20 dGy * cm2 versus 0.11 ± 0.00 to 2.46 ± 0.17 dGy * cm2 for tomosynthesis. Cortical bone display was inferior for radiographs compared to 40° and 20° tomosynthesis. Best results were ascertained for the 80 kV/40°/26 fps protocol. Trabecular bone depiction was also superior in tomosynthesis (p ≤ 0.009) and best with the 80 kV/10°/26 fps setting. Interreader reliability was moderate for cortical bone display (ICC 0.521, 95% confidence interval 0.356-0.641) and good for trabecular bone (0.759, 0.697-0.810). Diagnostic accuracy for articular involvement and multifragment situations was higher in tomosynthesis (93.8-100%/92.2-100%) vs. radiography (85.9%/82.8%.). Diagnostic confidence was also better in tomosynthesis (p ≤ 0.003). CONCLUSION: Compared to radiography, tomosynthesis allows for superior assessability of cortical and trabecular bone and fracture morphology, especially at high framerates. Operating on a multipurpose X-ray system, tomosynthesis of the appendicular skeleton can be performed without additional scanner hardware.

The impact of intensive training in preliminary image evaluation (PIE) for radiographers in the emergency department of a regional hospital in New Zealand - A pilot study.

INTRODUCTION: New Zealand has seen an increase in the X-ray examinations in the emergency departments (ED), and the radiology report is generally unavailable immediately. This requires practitioners managing the patient to take the responsibility of detecting any abnormalities in the images and using such information for the management of the patient. There is, therefore, a need for consideration of the contribution that radiographers could make in the accurate management of the patients in ED in New Zealand. The aim of this study was to assess if an intensive preliminary image evaluation (PIE) training course improved radiographer accuracy, sensitivity, and specificity on extremity X-ray examinations in a regional ED in New Zealand. METHOD: A pre-post-intervention design was employed for this study. Seven radiographers working at a regional base hospital in New Zealand undertook image evaluation tests to evaluate their ability to detect and describe abnormalities prior to and following a 2-day intensive PIE training course. The training concentrated on acute extremity abnormalities. Tests were then scored to determine sensitivity, specificity, and accuracy. RESULTS: Following an intensive PIE training course, the post-intervention test mean demonstrated an improved sensitivity by an average of 3.99% (89.01-93.0), specificity improved by an average of 6.13% (79.77-85.90%), and accuracy improved by an average of 3.33% (77.55-80.87%). CONCLUSION: This study demonstrated that an intensive training course in PIE improved the participants' sensitivity, specificity, and accuracy when evaluating acute extremity X-ray examinations in ED at the study site, however further research is required to see if these results also represent clinical ability. IMPLICATION FOR PRACTICE: The NZ healthcare system could benefit by the introduction of a radiographers' PIE system. It is therefore recommended that when introducing PIE into an ED in New Zealand, radiographers should undertake additional training to improve image evaluation sensitivity, specificity, and accuracy prior to participation.

Artificial intelligence-based detection of paediatric appendicular skeletal fractures: performance and limitations for common fracture types and locations.

BACKGROUND: Research into artificial intelligence (AI)-based fracture detection in children is scarce and has disregarded the detection of indirect fracture signs and dislocations. OBJECTIVE: To assess the diagnostic accuracy of an existing AI-tool for the detection of fractures, indirect fracture signs, and dislocations. MATERIALS AND METHODS: An AI software, BoneView (Gleamer, Paris, France), was assessed for diagnostic accuracy of fracture detection using paediatric radiology consensus diagnoses as reference. Radiographs from a single emergency department were enrolled retrospectively going back from December 2021, limited to 1,000 radiographs per body part. Enrolment criteria were as follows: suspected fractures of the forearm, lower leg, or elbow; age 0-18 years; and radiographs in at least two projections. RESULTS: Lower leg radiographs showed 607 fractures. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were high (87.5%, 87.5%, 98.3%, 98.3%, respectively). Detection rate was low for toddler's fractures, trampoline fractures, and proximal tibial Salter-Harris-II fractures. Forearm radiographs showed 1,137 fractures. Sensitivity, specificity, PPV, and NPV were high (92.9%, 98.1%, 98.4%, 91.7%, respectively). Radial and ulnar bowing fractures were not reliably detected (one out of 11 radial bowing fractures and zero out of seven ulnar bowing fractures were correctly detected). Detection rate was low for styloid process avulsions, proximal radial buckle, and complete olecranon fractures. Elbow radiographs showed 517 fractures. Sensitivity and NPV were moderate (80.5%, 84.7%, respectively). Specificity and PPV were high (94.9%, 93.3%, respectively). For joint effusion, sensitivity, specificity, PPV, and NPV were moderate (85.1%, 85.7%, 89.5%, 80%, respectively). For elbow dislocations, sensitivity and PPV were low (65.8%, 50%, respectively). Specificity and NPV were high (97.7%, 98.8%, respectively). CONCLUSIONS: The diagnostic performance of BoneView is promising for forearm and lower leg fractures. However, improvement is mandatory before clinicians can rely solely on AI-based paediatric fracture detection using this software.

Hindlimb and pelvic anatomy of Caiman yacare (Archosauria, Pseudosuchia): Myology and osteological correlates with emphasis on lower leg and autopodial musculature.

The anatomy of the archosaurian pelvis and hindlimb has adopted a diversity of successful configurations allowing a wide range of postures during the evolution of the group (e.g., erect, sprawling). For this reason, thorough studies of the structure and function of the pelvic and hindlimb musculature of crocodylians are required and provide the possibility to expand their implications for the evolution of archosaurian locomotion, as well as to identify potential new characters based on muscles and their bony correlates. In this study, we give a detailed description of the pelvic and hindlimb musculature of the South American alligator Caiman yacare, providing comprehensive novel information regarding lower limb and autopodial muscles. Particularly for the pedal muscles, we propose a new classification for the dorsal and ventral muscles of the autopodium based on the organisation of these muscles in successive layers. We have studied the myology in a global background in which we have compared the Caiman yacare musculature with other crocodylians. In this sense, differences in the arrangement of m. flexor tibialis internus 1, m. flexor tibialis externus, m. iliofibularis, mm. puboischiofemorales internii 1 and 2, between Ca. yacare and other crocodylians were found. We also discuss the muscle attachments that have different bony correlates among the crocodylian species and their morphological variation. Most of the correlates did not exhibit great variation among the species compared. The majority of the recognised correlates were identified in the pelvic girdle; additionally, some bony correlates associated with the pedal muscles are highlighted here for the first time. This research provides a wide framework for future studies on comparative anatomy and functional morphology, which could contribute to improving the character definition used in phylogenetic analyses and to understand the patterns of musculoskeletal hindlimb evolution.

Skeletal anatomy of the pectoral fin in mudskipper species from terrestrial and aquatic habitats.

Mudskippers are a group of amphibious fishes in the family Oxudercidae, whose species inhabit a range of habitats from mostly aquatic to mostly terrestrial. Most of our understanding about habitat preference comes from natural history observations, particularly where they are collected (i.e., low intertidal vs. high intertidal regions). Mudskippers have undergone several morphological changes to accommodate a terrestrial life, including major changes to the pectoral and pelvic girdles. These changes result in a novel crutching gait, which mudskippers use to move over land. Though the appendicular morphology and crutching gait of mudskippers have been described in some species, few studies have compared skeletal structures across the family. In our study, we use microcomputed tomography (µCT) scans to compare the skeletal anatomy of 16 species of aquatic and terrestrial mudskippers. Linear discriminant analysis is used to analyze measurements obtained through geometric morphometrics (landmarks). We found bone structures of the pectoral region in the terrestrial group were significantly longer and wider than those in the aquatic group. Furthermore, a significant difference in anatomy is shown between terrestrial and aquatic genera with both axial and appendicular elements contributing to the separation between groups. This work describes the differences in skeletal morphology associated with terrestriality in mudskippers and provides valuable insights into specific anatomical characteristics contributing to their adaptation to novel environments.

Fin systems comparative anatomy in model Batoidea Raja asterias and Torpedo marmorata: Insights and relatioships between musculo-skeletal layout, locomotion and morphology.

The macroscopic and microscopic morphology of the appendicular skeleton was studied in the two species Raja asterias (order Rajiformes) and Torpedo marmorata (Order Torpediniformes), comparing the organization and structural layout of pectoral, pelvic, and tail fin systems. The shape, surface area and portance of the T. marmorata pectoral fin system (hydrodynamic lift) were conditioned by the presence of the two electric organs in the disk central part, which reduced the pectoral fin surface area, suggesting a lower efficiency of the "flapping effectors" than those of R. asterias. Otherwise, radials' rays alignment, morphology and calcification pattern showed in both species the same structural layout characterized in the fin medial zone by stiffly paired columns of calcified tiles in the perpendicular plane to the flat batoid body, then revolving and in the horizontal plane to continue as separate mono-columnar rays in the fin lateral zone with a morphology suggesting fin stiffness variance between medial/lateral zone. Pelvic fins morphology was alike in the two species, however with different calcified tiles patterns of the 1st compound radial and pterygia in respect to the fin-rays articulating perpendicularly to the latter, whose tile rows lay-out was also different from that of the pectoral fins radials. The T. marmorata tail-caudal fin showed a muscular and connective scaffold capable of a significant oscillatory forward thrust. On the contrary, the R. asterias dorsal tail fins were stiffened by a scaffold of radials-like calcified segments. Histomorphology, heat-deproteination technique and morphometry provided new data on the wing-fins structural layout which can be correlated to the mechanics of the Batoid swimming behavior and suggested a cartilage-calcification process combining interstitial cartilage growth (as that of all vertebrates anlagen) and a mineral deposition with accretion of individual centers (the tiles). The resulting layout showed scattered zones of un-mineralized matrix within the calcified mass and a less compact texture of the matrix calcified fibers suggesting a possible way of fluid diffusion throughout the mineralized tissue. These observations could explain the survival of the embedded chondrocytes in absence of a canalicular system as that of the cortical bone.

The Prognostic Value of the Serum Level of C-Reactive Protein for Survival of Children with Ewing's Sarcoma.

The purpose of the present study was to evaluate the prognostic role of C-reactive protein (CRP) in children with Ewing's sarcoma. We conducted a retrospective study on 151 children undergoing multimodal treatment for Ewing's sarcoma in the appendicular skeleton from December 1997 to June 2020. Univariate Kaplan-Meier analyses of laboratory biomarkers and clinical parameters showed that CRP and metastatic disease at presentation were poor prognostic factors associated with overall survival and disease recurrence at 5 years (p < 0.05). A multivariate Cox regression model showed that pathological CRP (≥1.0 mg/dL) [HR of 3.67; 95% CI, 1.46 to 10.42] and metastatic disease [HR of 4.27; 95% CI, 1.58 to 11.47] were associated with a higher risk of death at 5 years (p < 0.05). In addition, pathological CRP (≥1.0 mg/dL) [HR of 2.66; 95% CI, 1.23 to 6.01] and metastatic disease [HR of 2.56; 95% CI, 1.13 to 5.55] were associated with a higher risk of disease recurrence at 5 years (p < 0.05). Our findings demonstrated that CRP was associated with the prognosis of children with Ewing's sarcoma. We recommend pre-treatment measurement of the CRP in order to recognize children with Ewing's sarcoma who are at greater risk of death or local recurrence.

Long-term follow up of patients with low-grade chondrosarcoma in the appendicular skeleton treated by extended curettage and liquid nitrogen.

BACKGROUND: Chondrosarcoma is the second most common sarcoma of bone, accounting for about 25% of primary bone tumors. Histological grading is the single most important determinant of local recurrence and metastases, where low-grade chondrosarcoma (grade 1: atypical cartilaginous lesion) is associated with 10 years survival rate 79-100%. There has been always a debate about the need for wide resection in managing low-grade chondrosarcoma, where several reports describe successful management with intra-lesional curettage and adjuvant therapy, minimizing the need for complex reconstructive procedures and improving the expected outcomes. HYPOTHESIS: Grade 1 chondrosarcoma of the appendicular skeleton can be successfully treated through extended curettage and liquid nitrogen with favorable oncological and functional outcomes. PATIENTS AND METHODS: We retrospectively assessed 113 patients with low grade chondrosarcoma in the appendicular skeleton, who were treated by extended curettage, adjuvant therapy using liquid nitrogen, reconstruction using polymethyl methacrylate and prophylactic fixation. Patients were assessed regarding incidence of recurrence, incidence of non-oncological complications and functional outcome. RESULTS: The mean follow up period was 110 months. In three patients (2.7%), local recurrence occurred. Five point three percent of the patients got non-oncological complications that were successfully managed. The mean MSTS score was 95%, with no evidence of distant metastases or disease related mortality. CONCLUSION: Grade 1 chondrosarcoma in the appendicular skeleton can be effectively treated using extended curettage, liquid nitrogen as adjuvant and cement as filler. Prophylactic fixation is required to avoid pathological fractures. When done properly, excellent functional outcome is expected. LEVEL OF EVIDENCE: IV, Case series (retrospective comparative study).

Diagnosis of Intraosseous Hibernoma of an Appendicular Skeleton in an Adult - A Rare Case Report.

Introduction: Hibernoma is an uncommon benign tumor composed of multivacuolated brown adipocytes described in the literature a decade back. Intraosseous hibernomas are extremely rare with propensity to affect axial skeleton. Involvement of appendicular skeleton has been reported only twice in the literature till date. Case Report: We present a case of solitary, painless mass in the left proximal tibia mimicking neoplasm in a 35-year-old male. The plain radiographs revealed a lytic lesion with well-defined margin at the junction of metaphyseal-diaphyseal region of the left proximal tibia. The lesion was hyperintense on T2 and hypointense on T1 with heterogenous enhancement on contrast imaging. FDG-PET showed high uptake of fluorodeoxyglucose. Histopathological examination revealed the presence of multivacuolated cytoplasm with abundant mitochondria suggestive of hibernoma. On immunohistochemistry, the cells were positive for S-100. Conclusion: The findings of imaging modalities are non-specific and histopathological examination is required to confirm the diagnosis of hibernoma. Intraosseous hibernoma needs to be considered as a differential diagnosis of sclerotic bone lesion. Further, evaluation with regular follow-up with imaging will be required if the mass undergoes any clinical changes. Both radiologists and pathologists, need to be aware of this rare entity to avoid misdiagnosis of the uncommon lesion.

Paleobiological inferences on middle Eocene native ungulates from South America: Functional morphological analysis of Notostylops and Notopithecus.

Eocene early-diverging representatives of South American extinct notungulates are traditionally considered to have been "generalists" and "non-specialized" in terms of the appendicular skeleton and locomotor behavior, as is the case with the notostylopid Notostylops, a middle Eocene iconic taxon from Patagonia (Argentina). However, they are mainly known from dental remains, and associated cranial and postcranial elements are scarce. The discovery of a nearly complete specimen attributed to N. murinus allows us to: (1) increase the knowledge of the anatomy of its appendicular skeleton; (2) identify isolated bones from several collections and suggest different taxonomic interpretations for published specimens; (3) perform a biomechanical and functional study using functional morphological analysis to infer its paleoecological attributes (e.g. posture, locomotor habit, estimated speed, and body mass); and (4) establish morphofunctional comparisons, based on possible functional ranges, with other extinct early-diverging notoungulates from the middle Eocene, such as the Notopithecid Notopithecus. Our evidence suggests that Notostylops was a medium-sized mammal (8.5-20 kg), which could achieve a dynamic digitigrade posture that allowed a scansorial secondary locomotor habit and a speed of up to 50 km/h. However, Notopithecus was a small-sized mammal (0.6-1.4 kg) with a plantigrade posture both in a static and dynamic context, terrestrial habits, and a speed of up to 35 km/h. Therefore, we conclude that these Eocene notoungulates show different locomotor capabilities, which can be associated with early niche diversifications, clearly contrasting with the "all-generalists" paradigmatic view.

The molecular genetics of human appendicular skeleton.

Disorders that result from de-arrangement of growth, development and/or differentiation of the appendages (limbs and digit) are collectively called as inherited abnormalities of human appendicular skeleton. The bones of appendicular skeleton have central role in locomotion and movement. The different types of appendicular skeletal abnormalities are well described in the report of "Nosology and Classification of Genetic skeletal disorders: 2019 Revision". In the current article, we intend to present the embryology, developmental pathways, disorders and the molecular genetics of the appendicular skeletal malformations. We mainly focused on the polydactyly, syndactyly, brachydactyly, split-hand-foot malformation and clubfoot disorders. To our knowledge, only nine genes of polydactyly, five genes of split-hand-foot malformation, nine genes for syndactyly, eight genes for brachydactyly and only single gene for clubfoot have been identified to be involved in disease pathophysiology. The current molecular genetic data will help life sciences researchers working on the rare skeletal disorders. Moreover, the aim of present systematic review is to gather the published knowledge on molecular genetics of appendicular skeleton, which would help in genetic counseling and molecular diagnosis.

Surgical Treatment of Metastatic Bone Disease in the Appendicular Skeleton: A Population-Based Study.

Background: Population-based studies of patients with bone metastases in the appendicular skeleton (aBM) requiring surgery for complete or impending fracture are rare. In this epidemiologically-based observational study we created a large population-based cohort of patients treated for aBM, aiming to: (1) monitor possible time-related changes of the incidence of surgical treatment of aBM-lesions, (2) examine differences in the population and care of patients treated at different treatment centers and (3) examine if findings from a previous pilot study regarding absence of a suitable biopsy of the lesions representing debut of cancer or a relapse has improved the awareness of aBM and hereby increased the focus on regular tumor biopsies and follow-up imaging of cancer patients. Methods: We examined a population-based cohort consisting of all patients treated for aBM 2014−2019. Procedures were performed at five secondary surgical centers (SSC) or one tertiary referral Musculoskeletal Tumor Center (MTC). Patients were followed until end of study (30 September 2021) or death. No patients were lost to follow-up. Results: Four-hundred-fifty-seven patients (493 primary aBM-lesions, 482 procedures) were included. Annual incidence of aBM-surgery was 46 aBM-lesions/million. MTC-patients had a significant better preoperative status than SSC-patients considering factors known for survival. Patients with complete fracture experienced longer surgical delay when treated at MTC compared to SSC: 4 (1−9) and 1 (1−3) days (p < 0.001), respectively. Overall survival for the entire cohort was 37% and 11% at 1 and 5 years (MTC and SSC 1 and 5 year respectively: 44% and 15% vs. 29% and 5%, p < 0.001). In patients with debut or relapse of cancer, 8% and 9% had insufficient biopsies, and 21% and 12% had no biopsy, respectively. Comparison showed no change over time. Conclusions: The current study highlights the low awareness on treating aBM at SSC and emphasizes the importance of caution in interpretation of studies not representing an entire population, thus introducing selection bias.

Femoral specializations to locomotor habits in early archosauriforms.

The evolutionary history of archosaurs and their closest relatives is characterized by a wide diversity of locomotor modes, which has even been suggested as a pivotal aspect underlying the evolutionary success of dinosaurs vs. pseudosuchians across the Triassic-Jurassic transition. This locomotor diversity (e.g., more sprawling/erect; crouched/upright; quadrupedal/bipedal) led to several morphofunctional specializations of archosauriform limb bones that have been studied qualitatively as well as quantitatively through various linear morphometric studies. However, differences in locomotor habits have never been studied across the Triassic-Jurassic transition using 3D geometric morphometrics, which can relate how morphological features vary according to biological factors such as locomotor habit and body mass. Herein, we investigate morphological variation across a dataset of 72 femora from 36 different species of archosauriforms. First, we identify femoral head rotation, distal slope of the fourth trochanter, femoral curvature, and the angle between the lateral condyle and crista tibiofibularis as the main features varying between bipedal and quadrupedal taxa, all of these traits having a stronger locomotor signal than the lesser trochanter's proximal extent. We show a significant association between locomotor mode and phylogeny, but with the locomotor signal being stronger than the phylogenetic signal. This enables us to predict locomotor modes of some of the more ambiguous early archosauriforms without relying on the relationships between hindlimb and forelimb linear bone dimensions as in prior studies. Second, we highlight that the most important morphological variation is linked to the increase of body size, which impacts the width of the epiphyses and the roundness and proximodistal position of the fourth trochanter. Furthermore, we show that bipedal and quadrupedal archosauriforms have different allometric trajectories along the morphological variation in relation to body size. Finally, we demonstrate a covariation between locomotor mode and body size, with variations in femoral bowing (anteroposterior curvature) being more distinct among robust femora than gracile ones. We also identify a decoupling in fourth trochanter variation between locomotor mode (symmetrical to semi-pendant) and body size (sharp to rounded). Our results indicate a similar level of morphological disparity linked to a clear convergence in femoral robusticity between the two clades of archosauriforms (Pseudosuchia and Avemetatarsalia), emphasizing the importance of accounting for body size when studying their evolutionary history, as well as when studying the functional morphology of appendicular features. Determining how early archosauriform skeletal features were impacted by locomotor habits and body size also enables us to discuss the potential homoplasy of some phylogenetic characters used previously in cladistic analyses as well as when bipedalism evolved in the avemetatarsalian lineage. This study illuminates how the evolution of femoral morphology in early archosauriforms was functionally constrained by locomotor habit and body size, which should aid ongoing discussions about the early evolution of dinosaurs and the nature of their evolutionary "success" over pseudosuchians.

Descripción anatómica de los segmentos óseos que componen el esqueleto apendicular torácico de la especie Puma concolor / Anatomical description of the bony segments that make up the thoracic appendicular skeleton of the species Puma concolor

RESUMEN: El Puma concolor es uno de los carnívoros más grandes presentes en Chile, aunque su tamaño varía según la zona geográfica en la que se encuentra. Cada vez es más común encontrarlos fuera de su hábitat y más en nuestro entorno. Se conocen sus aspectos ecológicos, reproductivos y nutricionales, pero muy poco de su anatomía, lo que genera un desafío en el área morfológica veterinaria que necesita fortalecimiento. El presente estudio consistió en una descripción anatómica del esqueleto apendicular de tres ejemplares adultos de Puma concolor (3 machos) en el laboratorio de anatomía veterinaria de la Universidad San Sebastián, sede de la Patagonia Puerto Montt, lo que permitió un estudio detallado de la conformación del esqueleto de cada estructura presente en el esqueleto apendicular torácico de estos ejemplares. Esto nos permitió lograr resultados de interés morfológico y profundizar en la anatomía de esta especie.

SUMMARY: The Puma concolor is one of the largest carnivores present in Chile, although its size varies according to the geographical area in which it is found. It is increasingly common to find them outside their habitat and more in our environment. Its ecological, reproductive and nutritional aspects are known, but very little is known about its anatomy, which creates a challenge in the veterinary morphological area that needs strengthening. The present study consisted of an anatomical description of the appendicular skeleton of three adult specimens of Puma concolor (3 males) in the veterinary anatomy laboratory of the Universidad San Sebastián, headquarters of Patagonia Puerto Montt, which allowed a detailed study of the conformation of the skeleton of each structure present in the thoracic appendicular skeleton of these specimens. This allowed us to achieve results of morphological interest and delve into the anatomy of this species.

The postcranial skeleton of Cerrejonisuchus improcerus (Crocodyliformes: Dyrosauridae) and the unusual anatomy of dyrosaurids.

Dyrosauridae is a clade of neosuchian crocodyliforms that diversified in terrestrial and aquatic environments across the Cretaceous-Paleogene transition. The postcranial anatomy of dyrosaurids has long been overlooked, obscuring both their disparity and their locomotive adaptations. Here we thoroughly describe of the postcranial remains of an unusually small dyrosaurid, Cerrejonisuchus improcerus, from the middle-late Paleocene Cerrejón Formation of Colombia, and we provide a wealth of new data concerning the postcranial anatomy of the key dyrosaurids: Congosaurus bequaerti and Hyposaurus rogersii. We identify a series of postcranial autapomorphies in Cerrejonisuchus improcerus (an elliptic-shaped odontoid laterally wide, a ulna possessing a double concavity, a fibula bearing a widely flattened proximal end, a pubis showing a large non-triangular distal surface) as well as functionally-important traits such as a relatively long ulna (85% of the humerus' length), short forelimb (83% of hindlimb's length), or thoracic vertebra bearing comparatively large lateral process (with widened parapophysis and diapophysis) along with strongly arched thoracic ribs allowing a more sturdy and cylindrical rib cage. These indicate a more terrestrial lifestyle for Cerrejonisuchus compared to the derived members of the clade. We also built a dataset of 187 traits on 27 taxa, that extensively samples the cranial and postcranial architectures of exemplar crocodyliforms. We analyze these data in via Principal Coordinate Analysis (PCoA) to visualize the postcranial morphospace occupation of Dyrosauridae, Thalattosuchia, and Crocodylia. Our data reveal the existence of a distinctive postcranial anatomy for Dyrosauridae that is markedly distinct from that of crocodylians. As a result, modern crocodylians are probably not good functional analog for extinct crocodyliformes. Postcranial data should also be more widely used in phylogenetic and disparity analyses of Crocodyliformes.

A new synapomorphy in the pelvic girdle reinforces a close relationship of Zanobatus and Myliobatiformes (Chondrichthyes: Batoidea).

The rays of the order Myliobatiformes present several diagnostic characters, the most striking one being the presence of a serrated sting on the dorsal region of the tail. Although several morphological hypotheses have been proposed supporting the monophyly and interrelationships of its members, few characters of the appendicular skeleton were employed. In the present study, we analyzed comparatively the pelvic girdle morphology across all the groups of rays to investigate the distribution of the ischial process. To understand its significance, we tested this character of the pelvic girdle as a potential synapomorphy for the Myliobatiformes plus Zanobatus. Accordingly, the phylogenetic position of Zanobatus as a sister taxon to Myliobatiformes is reinforced and its pelvic girdle morphology reinterpreted in relation to previous morphological studies.

Accuracy of radiographer comment following a two-month experiential and blended learning in appendicular skeleton X-ray interpretation: The Singapore experience.

INTRODUCTION: The value of combined blended and experiential learning on radiographer diagnostic comment has not been explored. This study aims to examine the accuracy of image interpretation comment of radiographers who received a period of blended and experiential learning in Radiographer Abnormality Detection Systems (RADS). METHODS: We evaluated the diagnostic opinions of 13 radiographers who received a blended training and experiential learning (a process of self-learning and reflection) in RADS. Radiographers' opinions on 16,483 images were examined using the final radiologists' report as a reference standard. For each radiographer, we recorded the number of true positive, true negative, false positive and false negative opinions and MedCal® was used to calculate diagnostic performance and error rates. A t-test was used to assess whether the number of images read was associated with performance and whether the radiographers retained performance over time. RESULTS: Sensitivity ranged from 87.4 (84.0-90.2) to 98.9 (97.5-99.7) with a mean of 94.3 (93.6-94.8). Specificity varied from 96.4 (94.8-97.5) to 99.9 (99.41-100.0) with a mean of 98.2 (97.9-98.4). Diagnostic accuracy ranged from 93.1 (91.5-94.4) to 99.5 (98.9-99.8) with a mean of 96.9 (96.6-97.1). The mean false positive rate was 0.018 (range: 0.010-0.031) with a false negative rate of 0.057 (range: 0.026-0.11). There were no differences in performance between the first and latter nine months of providing opinions and the number of images reviewed was not associated with performance. CONCLUSION: Radiographers who received blended and experiential learning in RADS provide accurate diagnostic comments on plain emergency appendicular skeleton radiographs. IMPLICATION FOR PRACTICE: A combined blended and experiential learning can equip radiographers to provide diagnostic opinion on plain appendicular skeleton radiographs.

A reappraisal of the pectoral skeleton of lantern sharks (Elasmobranchii: Squaliformes: Etmopteridae).

The morphology of the articular region of the pectoral girdle and associated basals in Etmopteridae is revised in light of new evidence provided by taxa unavailable for previous studies. Such studies considered that etmopterids plesiomorphically had a single pectoral articular condyle, and only Etmopterus had two separate ones. Our reanalysis indicates that the possession of two separate condyles, one for the articulation of the propterygium and the second for the meso- and metapterygium, is the most widespread condition in this group. However, the presence of two separate articular condyles is not recovered as a synapomorphy for Etmopteridae. Previous studies also proposed that etmopterids lack a hook-like process on the anteroproximal margin of the anteriormost pectoral basal. We document that the hook-like process is plesiomorphically present in Etmopteridae, thus corroborating the hypothesis of closer relationships between this family and the other squaliforms that also share this process, namely Centrophoridae, Dalatiidae, Oxynotidae, and Somniosidae.

Multicentric chondrosarcoma involving the appendicular skeleton: a case report and literature review.

Chondrosarcomas constitute the 3rd most common primary bone malignancy. These tumours grow slowly and rarely metastasize, usually having a good prognosis after surgery. Among patients registered and treated at the Brazilian National Institute of Traumatology and Orthopedics, an uncommon case of chondrosarcoma was identified in a 63-year-old man, who was diagnosed with multicentric chondrosarcoma of the appendicular skeleton. This example is atypical in the medical literature because multicentric tumours are different from metastatic events, and their frequency in chondrosarcoma is rare. This article therefore provides a rare case report alongside a review of additional cases in the medical literature.