Synovial Sarcoma of the Foot as an Atypical Cause of Persistent Metatarsalgia: A Report of 3 Cases.

CASE: Three cases of atypical metatarsalgia are presented, all diagnosed with foot synovial sarcomas (SSs) at different stages of evolution, after a year of medical consultations. One case was treated with marginal excision without requiring bone excision; the second patient required amputation of the first ray; and the third patient, with advanced disease, required amputation through Chopart's joint. CONCLUSION: Metatarsalgia is a recurrent reason for consultation in orthopaedics. Even so, patients with persistent symptoms should be studied further in depth. Computed tomography or magnetic resonance imaging can detect tumor pathology, such as SS, of insidious development.

Hidradenocarcinoma over a Surgically Excised Hidradenoma of the Foot. A Case Report of a Very Rare Presentation of a Rare Tumor.

Introduction: Hidradenocarcinomas are very rare and aggressive soft-tissue tumors, originated from sweat gland cells, which are located most frequently in head and neck, being their appearance at the extremities rare. This kind of tumor usually appears de novo and very few cases have been reported until now of appearance over benign lesions such as hidradenomas. Malignancy progression rate of hidradenomas is unknown, and this benign lesion has clinical and histopathological characteristics in common with hidradenocarcinomas that could lead to misdiagnosis. Hidradenocarcinomas have a very poor survival rate; therefore, an early diagnosis is essential for a better prognosis, and that is the reason why hidradenomas should be widely excised from the beginning, instead of performing marginal resections of this lesions that could lead to an aggressive recurrence. Case Presentation: Here is a case report of a 27-year-old woman diagnosed with a hidradenocarcinoma over a previously excised hidradenoma in the right foot. The diagnosis was made after right pelvic and inguinal lymphadenopathies appeared few months after a new small asymptomatic lump appeared at the same place in the sole of the right foot were the excised hidradenoma five years before was located. Lymph node biopsy was performed, with histopathological diagnosis of hidradenocarcinoma metastasis. Surgical local wide excision of the lump at the foot and lymphadenectomies was performed. Histopathological analysis of the samples confirmed the diagnosis of hidradenocarcinoma. The patient later received adjuvant radiotherapy and after one year there are no signs of disease recurrence. Conclusion: Many questions remain uncertain about the management and treatment of hidradenocarcinomas due to the rarity of this type of tumor. Although targeted molecular therapies have shown promising results, more studies in this field are necessary. An early diagnosis and differentiation from its benign counterparts that allow local control of the disease before spreading is essential to improve survival rates.

Orthopedic Surgical Treatment and Perioperative Complications in Multiple Myeloma Bone Disease: Analysis of a Series (2009-2018).

BACKGROUND: More than 90% of patients with multiple myeloma (MM) develop lytic bone lesions that can be surgically treated for symptomatic relief and functional improvement. METHODS: This was a retrospective observational analytic study conducted between 2009 and 2018, including 58 patients with MM bone disease who underwent 77 orthopedic surgical procedures and were co-managed by internal medicine. Analysis of data related to MM bone disease, different modalities of surgical treatment, perioperative complications, and survival was performed. RESULTS: Median age was 72 years (66.5-77 years) and 56.9% of patients were males; 54.43% of injuries were located in the spine, 27.85% in the pelvis or lower limbs, 15.19% in the upper limbs, and 75.32% of patients had pathologic fractures. In 29.31% of the cases, the bone lesion was the debut of MM. Surgical procedures performed were mainly kyphoplasty (48.05%) and intramedullary nailing (29.87%). The overall complication rate following surgery was 74.03%. Only 20.78% of cases had a surgical complication. Among medical complications, we registered 28.57% transfusion requirements, 25.97% acute renal failures, 24.68% developed an infection, and 10.39% developed hypercalcemia. Patients were followed-up for a mean of 6.13 years and 37.93% suffered a new fracture. The median overall survival time for patients after surgery was 32.9 months (11.6-49). The estimated overall survival at 1, 3, and 5 years after surgery was 81.17%, 57%, and 34.11%, respectively. CONCLUSIONS: The orthopedic surgical treatment of MM bone disease aims to improve symptomatology and patient quality of life; however, these patients have a high risk of perioperative complications and considerable early mortality, making multidisciplinary management with medical specialties essential.

The role of environment, dispersal and competition in explaining reduced co-occurrence among related species.

The composition of ecological assemblages depends on a variety of factors including environmental filtering, biotic interactions and dispersal limitation. By evaluating the phylogenetic pattern of assemblages, we gain insight into the relative contribution of these mechanisms to generating observed assemblages. We address some limitations in the field of community phylogenetics by using simulations, biologically relevant null models, and cost distance analysis to evaluate simultaneous mechanisms leading to observed patterns of co-occurrence. Building from past studies of phylogenetic community structure, we applied our approach to hummingbird assemblages in the Northern Andes. We compared the relationship between relatedness and co-occurrence among predicted assemblages, based on estimates of suitable habitat and dispersal limitation, and observed assemblages. Hummingbird co-occurrence peaked at intermediate relatedness and decreased when a closely-related species was present. This result was most similar to simulations that included simultaneous effects of phylogenetic conservatism and repulsion. In addition, we found older sister taxa were only weakly more separated by geographic barriers, suggesting that time since dispersal is unlikely to be the sole factor influencing co-occurrence of closely related species. Our analysis highlights the role of multiple mechanisms acting simultaneously, and provides a hypothesis for the potential importance of competition at regional scales.

A clinical review of 11 cases of large-sized well-differentiated liposarcomas.

Well-differentiated liposarcomas of the extremities are one of the most frequent types of malignant soft tissue tumors in adults. These tumors are typically locally aggressive and show a tendency to recurrence after surgical excision even though they do not metastasize and very rarely dedifferentiate. Its clinical presentation is generally a progressively growing mass causing aesthetic, functional, or compressive symptoms depending on the tumor's size and localization. Several authors recommend a wide excision with free margins in order to minimize the risk of recurrence, while others report good results and a low rate of recurrence with more conservative or even marginal excision thereby avoiding complications due to surgical site morbidity. We present a retrospective study of 11 patients with a large-sized well-differentiated liposarcoma of the lower limb with a mean follow-up of 3.2 years. The mean size was 22 × 19 × 17 cm, and a marginal resection was made, respecting the affected neurovascular structures, in all cases. Only one recurrence was found and the functional results were 81.6% according to the MSTS functional scale 1 year after surgery. We believe that the marginal excision is a good alternative when the tumor is located near vascular or nerve structures, and as to our experience, it is not associated with elevated recurrences.

Paraneoplastic vasculitis associated to pelvic chondrosarcoma: a case report.

Vasculopathic syndromes have been associated with hematological and solid organ malignancies. The pathogenesis of these syndromes remains largely unknown and there are no biologic markers identified. Whether it is or is not a paraneoplastic syndrome is under discussion, the close temporal relationship of cancer and vasculitis suggests that these vasculitides are a paraneoplastic condition. We report a case of a 45-year-old female patient with pelvic chondrosarcoma who underwent surgical treatment and started to present visual loss, systemic inflammatory response syndrome (SRIS), cardiac insufficiency, hepatosplenomegaly, cholestasis as well as pulmonary bleeding suggesting a sarcoma-associated vasculitis. All antibodies were negative as in secondary vasculitis. After corticoideal therapy the vasculitis resolved and at 3-year follow-up the patient had not showed any further medical complications or recurrences of the vasculitis. The parallel evolution of the vasculitis and the solid tumor combined with the resolution of the vasculitis after corticotherapy enhances the likelihood of a paraneoplastic vasculitis associated with a chondrosarcoma according to literature review.

Taxonomic, phylogenetic, and trait Beta diversity in South American hummingbirds.

Comparison of the taxonomic, phylogenetic, and trait dimensions of beta diversity may uncover the mechanisms that generate and maintain biodiversity, such as geographic isolation, environmental filtering, and convergent adaptation. We developed an approach to predict the relationship between environmental and geographic distance and the dimensions of beta diversity. We tested these predictions using hummingbird assemblages in the northern Andes. We expected taxonomic beta diversity to result from recent geographic barriers limiting dispersal, and we found that cost distance, which includes barriers, was a better predictor than Euclidean distance. We expected phylogenetic beta diversity to result from historical connectivity and found that differences in elevation were the best predictors of phylogenetic beta diversity. We expected high trait beta diversity to result from local adaptation to differing environments and found that differences in elevation were correlated with trait beta diversity. When combining beta diversity dimensions, we observe that high beta diversity in all dimensions results from adaption to different environments between isolated assemblages. Comparisons with high taxonomic, low phylogenetic, and low trait beta diversity occurred among lowland assemblages separated by the Andes, suggesting that geographic barriers have recently isolated lineages in similar environments. We provide insight into mechanisms governing hummingbird biodiversity patterns and provide a framework that is broadly applicable to other taxonomic groups.

Birds of Antioquia: Georeferenced database of specimens from the Colección de Ciencias Naturales del Museo Universitario de la Universidad de Antioquia (MUA).

The department of Antioquia, Colombia, lies in the northwestern corner of South America and provides a biogeographical link among divergent faunas, including Caribbean, Andean, Pacific and Amazonian. Information about the distribution of biodiversity in this area is of relevance for academic, practical and social purposes. This data paper describes the dataset containing all bird specimens deposited in the Colección de Ciencias Naturales del Museo Universitario de la Universidad de Antioquia (MUA). We curated all the information associated with the bird specimens, including the georeferences and taxonomy, and published the database through the Global Biodiversity Information Facility network. During this process we checked the species identification and existing georeferences and completed the information when possible. The collection holds 663 bird specimens collected between 1940 and 2011. Even though most specimens are from Antioquia (70%), the collection includes material from several other departments and one specimen from the United States. The collection holds specimens from three endemic and endangered species (Coeligena orina, Diglossa gloriossisima, and Hypopirrhus pyrohipogaster), and includes localities poorly represented in other collections. The information contained in the collection has been used for biodiversity modeling, conservation planning and management, and we expect to further facilitate these activities by making it publicly available.

Benefits of early intramedullary nailing in femoral metastases.

PURPOSE: Pathological fractures of the long bones are common complications of metastatic disease; however, the outcome of different surgical techniques for the treatment of these fractures has not been clearly defined. The aim of this study was to evaluate differences in prophylactic and therapeutic intramedullary nailing in femoral metastasic implants. METHODS: Sixty-five patients with metastasis of the femur were analysed retrospectively (37 females; 28 males) between 1995 and 2011 (follow-up 15 months). Forty-four presented with pathological fractures and 21 impending fractures (Mirel ≥7). The operative treatments used were intramedullary fixation with reamed long Gamma nails. The studied parameters were survival, radiological and analytical findings, and functional outcomes. RESULTS: Prophylactic nailing resulted in immediate postoperative deaths in 5% vs. 11.4% in therapeutic, and one technical complication was detected in each group. Among the surviving patients 75.9% of the fractures and 100 % of impending lesions were able to walk after the operation. The mean survival time was 11 months in the therapeutic (range 1-49) and 14 in the prophylactic group (1-34). The prophylactic intramedullary nails required a lower transfusion rate (1.4 concentrates vs. 3.0), mobilised earlier (day 4.0 vs. 9.7) and needed a shorter hospital stay (eight days vs. 16 days) compared to therapeutic nails (p < 0.05). CONCLUSION: Femoral intramedullary nailing of metastasic lesions provides satisfactory results both clinically and radiologically. Early treatment of the metastases prevents fractures and gives better results, improving life quality of these patients.

Management of infectious discitis. Outcome in one hundred and eight patients in a university hospital.

PURPOSE: The optimal management of pyogenic discitis is not agreed on. We conducted a retrospective, cross-sectional, observational study in which all patients with discitis who attended Hospital San Carlos Madrid from January 1999 to January 2009 were included. METHODS: We identified 108 consecutive adult patients with infectious discitis. There were 49 men and 59 women with an average age of 67,5 (+/- 16,89) years in the study group. Mean follow-up interval was 6,06 (12,5-2) years. 78 patients had spontaneous discitis and 30 patients had postoperative discitis. Inclusion criteria for the review were illness compatible with vertebral infection and / or evidence of spinal involvement on magnetic resonance imaging (MRI). RESULTS: In 56 percutaneous discal biopsy (52% patients) were positive in 28 cases. A single disc was infected in 100 patients. The segments involved were the cervical spine in four, the thoracic spine in 38 and the lumbar spine in 66. One or more comorbid diseases were present in 73 (68%) of 108 patients. Diabetes mellitus was the most common disease. Comorbid disease was rapidly fatal in four patients, ultimately fatal in seven patients, and nonfatal or not present in 97 patients (90 %). CONCLUSION: Early diagnosis is a major challenge. Heightened awareness and the prompt use of MRI are necessary to avoid diagnostic delay. Prolonged antimicrobial therapy and the judicious application of timely surgical intervention are essential for an optimal outcome.

Latitude, elevational climatic zonation and speciation in New World vertebrates.

Many biodiversity hotspots are located in montane regions, especially in the tropics. A possible explanation for this pattern is that the narrow thermal tolerances of tropical species and greater climatic stratification of tropical mountains create more opportunities for climate-associated parapatric or allopatric speciation in the tropics relative to the temperate zone. However, it is unclear whether a general relationship exists among latitude, climatic zonation and the ecology of speciation. Recent taxon-specific studies obtained different results regarding the role of climate in speciation in tropical versus temperate areas. Here, we quantify overlap in the climatic distributions of 93 pairs of sister species of mammals, birds, amphibians and reptiles restricted to either the New World tropics or to the Northern temperate zone. We show that elevational ranges of tropical- and temperate-zone species do not differ from one another, yet the temperature range experienced by species in the temperate zone is greater than for those in the tropics. Moreover, tropical sister species tend to exhibit greater similarity in their climatic distributions than temperate sister species. This pattern suggests that evolutionary conservatism in the thermal niches of tropical taxa, coupled with the greater thermal zonation of tropical mountains, may result in increased opportunities for allopatric isolation, speciation and the accumulation of species in tropical montane regions. Our study exemplifies the power of combining phylogenetic and spatial datasets of global climatic variation to explore evolutionary (rather than purely ecological) explanations for the high biodiversity of tropical montane regions.

Color evolution in the hummingbird genus coeligena.

The remarkable diversity of coloration and species present in hummingbirds has been considered the result of sexual selection. I evaluate if color differences among species in the genus Coeligena are consistent with expectations from sexual selection theory. If sexual selection on color is important for speciation, closely related species should be markedly different in the colors of feather patches associated with aggression and breeding. I evaluate this prediction through a statistical assessment of the phylogenetic signal of colors from five feather patches: crown, gorget, belly, upper back, and rump. The first two are associated with aggressive and courtship displays and are expected to be under sexual selection, whereas the others are not. Contrary to expectations, the crown and gorget were the only patches with significant phylogenetic signal. Furthermore, I assess if populations of dichromatic species are more divergent in coloration and therefore have reduced gene flow. Color distances among dichromatic subspecies were larger than among monochromatic subspecies, but the magnitude of phenotypic differentiation was not related to levels of gene flow. These results support a role for sexual selection in shaping color variation among populations, but these differences alone are not sufficient to explain speciation.

Molecular phylogenetics of the hummingbird genus Coeligena.

Advances in the understanding of biological radiations along tropical mountains depend on the knowledge of phylogenetic relationships among species. Here we present a species-level molecular phylogeny based on a multilocus dataset for the Andean hummingbird genus Coeligena. We compare this phylogeny to previous hypotheses of evolutionary relationships and use it as a framework to understand patterns in the evolution of sexual dichromatism and in the biogeography of speciation within the Andes. Previous phylogenetic hypotheses based mostly on similarities in coloration conflicted with our molecular phylogeny, emphasizing the unreliability of color characters for phylogenetic inference. Two major clades, one monochromatic and the other dichromatic, were found in Coeligena. Closely related species were either allopatric or parapatric on opposite mountain slopes. No sister lineages replaced each other along an elevational gradient. Our results indicate the importance of geographic isolation for speciation in this group and the potential interaction between isolation and sexual selection to promote diversification.

Diagnosis of infection in hip and knee revision surgery: intraoperative frozen section analysis.

UNLABELLED: In this study we validated intraoperatively the analysis of polymorphonuclear leucocyte frozen sections for diagnosis of infection in hip and knee revisions. Between 1996 and 2002 we examined sections and cultured periprosthetic tissues in prosthetic revision in 170 cases, including 146 cases (83 hips and 63 knees). We assessed sensitivity (SE), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), Youden index, positive likelihood ratio (PLR) and negative likelihood ratio (NLR). We compared intraoperative findings and paraffin-embedded samples. The results in the knee group were SE=66.7%, SP=89.7% [95% confidence interval (CI)], PPV=81% (95% CI), NPV=81.4% (95% CI), Youden index=0.56, PLR=6.5 (95% CI) and NLR=0.4 (95% CI). In the paraffin-embedded samples the results were SE=91%, SP=87% (95% CI), PPV=81% (95% CI), NPV=94% (95% CI), PLR=7 (95% CI) and NLR=8.7 (95% CI). We found a significant difference. The results in the hip group were SE=50%, SP=100% (95% CI), PPV=100% (95% CI), NPV=94.9% (95% CI), Youden index=0.5 and PLR=0.5 (95% CI). In hip and knee prosthetic revision surgery the presence of polymorphonuclear cells correlates with infection, but their absence does not exclude it. It is a quick and inexpensive test that should be included in the diagnostic protocol in revision surgery. LEVEL OF EVIDENCE: diagnostic Study (investigating a diagnostic test), level I. See instructions to authors for a complete description of levels of evidence.