An online training and feedback module enhances the musculoskeletal examination performance of medical interns.

BACKGROUND: Pathologies of the locomotor system are frequent and can cause disability and impact the quality of life of the people affected. In recent years, online training and feedback have emerged as learning tools in many fields of medicine. OBJECTIVE: This study aims to evaluate medical interns' musculoskeletal examination performance after completing an online training and feedback module. METHODS: This study employed a quasi-experimental design. Medical interns were invited to complete a 4-week musculoskeletal physical examination training and feedback module via an e-learning platform. The course included written and audiovisual content pertaining to medical history, physical examination, and specific tests for the diagnosis of the most common knee, spine, shoulder, ankle, and foot conditions. Before and after completing the module, their ability to perform the physical examination was evaluated using an objective structured clinical examination (OSCE) with simulated patients that took place face-to-face. A control group of experts was assessed using the OSCE, and their performance was compared to that of the interns before and after the training. At the end of the module feedback on the OSCE was provided to participants through the platform asynchronously and two evaluation questions about the user experience were conducted at the end of the study. RESULTS: A total of 35 subjects were assessed using the OSCE, including 29 interns and 6 experts. At the beginning of the training module, the group of interns obtained an average score of 50.6 ± 15.1. At the end of the module, 18 interns retook the OSCE, and their performance increased significantly to an average of 76.6 ± 12.8 (p < 0.01). Prior to the training, the experts performed significantly better than the interns (71.2 vs. 50.6; p = 0.01). After the interns received the training and feedback, there were no significant differences between the two groups (71.2 vs. 76.6; p = 0.43). Two evaluation questions were conducted at the end of the study, revealing that 93% of the participants affirm that the training module will be useful in their clinical practice, and 100% of the participants would recommend the training module to a colleague. CONCLUSION: The online training and feedback module enhances the musculoskeletal examination performance of medical interns.

Design of Microbial Consortia Based on Arbuscular Mycorrhizal Fungi, Yeasts, and Bacteria to Improve the Biochemical, Nutritional, and Physiological Status of Strawberry Plants Growing under Water Deficits.

Drought affects several plant physiological characteristics such as photosynthesis, carbon metabolism, and chlorophyll content, causing hormonal and nutritional imbalances and reducing nutrient uptake and transport, which inhibit growth and development. The use of bioinoculants based on plant growth-promoting microorganisms such as plant growth-promoting rhizobacteria (PGPR), yeasts, and arbuscular mycorrhizal fungi (AMF) has been proposed as an alternative to help plants tolerate drought. However, most studies have been based on the use of a single type of microorganism, while consortia studies have been scarcely performed. Therefore, the aim of this study was to evaluate different combinations of three PGPR, three AMF, and three yeasts with plant growth-promoting attributes to improve the biochemical, nutritional, and physiological behavior of strawberry plants growing under severe drought. The results showed that the growth and physiological attributes of the non-inoculated plants were significantly reduced by drought. In contrast, plants inoculated with the association of the fungus Claroideoglomus claroideum, the yeast Naganishia albida, and the rhizobacterium Burkholderia caledonica showed a stronger improvement in tolerance to drought. High biomass, relative water content, fruit number, photosynthetic rate, transpiration, stomatal conductance, quantum yield of photosystem II, N concentration, P concentration, K concentration, antioxidant activities, and chlorophyll contents were significantly improved in inoculated plants by up to 16.6%, 12.4%, 81.2%, 80%, 79.4%, 71.0%, 17.8%, 8.3%, 6.6%, 57.3%, 41%, and 22.5%, respectively, compared to stressed non-inoculated plants. Moreover, decreased malondialdehyde levels by up to 32% were registered. Our results demonstrate the feasibility of maximizing the effects of inoculation with beneficial rhizosphere microorganisms based on the prospect of more efficient combinations among different microbial groups, which is of interest to develop bioinoculants oriented to increase the growth of specific plant species in a global scenario of increasing drought stress.

Safety and exposure area in three different posteromedial surgical approaches for the treatment of ankle fractures. A cadaveric study.

INTRODUCTION: This study aimed to compare the degree of posterior malleolar exposure, the tension of the flap containing the posteromedial neurovascular bundle (NVB), and the distance between the surgical incision and the NVB using three different posteromedial ankle approaches. METHODS: Three approaches were compared: medial posteromedial (MePM) modified posteromedial (MoPM) and posteromedial (PM). We measured the minimal tension of the flap containing the NVB that allowed proper exposure. In the second stage, an axial cut was performed, and we measured the degree of posterior malleolar exposure and the distance between the incision and the NVB RESULTS: There were significant differences between the three approaches examined regarding the degree of posterior malleolar exposure and distance from the incision to the NBV,favoring the PM approach (71,00% ± 1.83 and 25.50 mm ± 4.20). The PM approach provided a significantly lower tension to the flap containing the posteromedial NVB (6.18 N ± 1.28) compared to the other two approaches CONCLUSION: The PM approach achieved the highest degree of posterior malleolar exposure, the lowest tension to the posteromedial NVB, and the greatest distance between the incision and the NBV. Thus, we believe it should be considered the approach of choicefor large fractures of the posteromedial aspect of the PM.

Post-operative complications affect survival in surgically treated metastatic spinal cord compression.

PURPOSE: The prevalence of metastatic epidural spinal cord compression (MESCC) is increasing globally due to advancements in cancer diagnosis and treatment. Whilst surgery can benefit specific patients, the complication rate can reach up to 34%, with limited reporting on their impact in the literature. This study aims to analyse the influence of major complications on the survival of surgically treated MESCC patients. METHODS: Consecutive MESCC patients undergoing surgery and meeting inclusion criteria were selected. Survival duration from decompressive surgery to death was recorded. Perioperative factors influencing survival were documented and analysed. Kaplan-Meier survival analysis at one year compared these factors. Univariate and multivariate Cox proportional hazard regression analyses were performed. Additionally, univariate analysis compared complicated and uncomplicated groups. RESULTS: Seventy-five patients were analysed. Median survival for this cohort was 229 days (95% CI 174-365). Surgical complications, low patient performance, and rapid primary tumour growth were significant perioperative variables for survival in multivariate analyses (p < 0.001, p = 0.003, and p = 0.02, respectively) with a hazard ratio of 3.2, 3.6, and 2.1, respectively. Univariate analysis showed no variables associated with complication occurrence. CONCLUSION: In this cohort, major surgical complications, patient performance, and primary tumour growth rate were found to be independent factors affecting one year survival. Thus, prioritizing complication prevention and appropriate patient selection is crucial for optimizing survival in this population.

Use of electromyographic biofeedback in rehabilitation following anterior cruciate ligament reconstruction: a systematic review and meta-analysis.

BACKGROUND: Rehabilitation following anterior cruciate ligament (ACL) reconstruction surgery is essential to regain functionality and return to previous activity level. Electromyographic biofeedback may be an effective intervention for rehabilitation of patients following ACL surgery. OBJECTIVE: To synthesize the available evidence on the effect of electromyographic biofeedback in the treatment of quadriceps strength following ACL surgery. DESIGN: Systematic review with meta-analysis. DATA SOURCES: PubMed, EMBASE, CENTRAL and Epistemonikos were searched. ELIGIBILITY CRITERIA: Randomized clinical trials with patients undergoing ACL reconstruction surgery comparing biofeedback with a standard rehabilitation control group. DATA EXTRACTION AND DATA SYNTHESIS: Two authors selected articles and performed data extraction. The analysed outcomes were strength, function, pain, knee extension and balance. The risk of bias of individual studies was assessed using the Cochrane Risk of Bias Tool. Results were combined through random-effects meta-analysis, reporting mean differences. RESULTS: Eight articles were included in the qualitative analysis, and four articles were included in the quantitative analysis. The interventions lasted between 4 and 12 weeks. Three studies evaluated the effect of biofeedback on quadriceps strength; of these, two studies showed a significant difference in favour of the biofeedback group. In addition, biofeedback was found to improve knee extension [standardized mean difference - 1.3, 95% confidence interval (CI) - 1.74 to -0.86] and balance (one study). There was no significant difference in Lysholm score (mean difference -6.21, 95% CI -17.51 to 5.08; I2 =59%) or pain between the biofeedback group and the control group. CONCLUSION: Electromyographic biofeedback in knee rehabilitation could be useful following ACL reconstruction surgery. KEY MESSAGES: SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO (CRD42020193768).

Aceptación y reticencia a las vacunas contra COVID-19 en ingresantes a una universidad pública peruana durante la tercera ola pandémica

Introducción. Los estudiantes universitarios influyen en las decisiones de su familia y comunidad a favor de la vacunación. Objetivo. Identificar las principales razones para la aceptación o reticencia vacunal contra COVID-19 en ingresantes a una universidad pública. Métodos. Estudio transversal en una muestra de 408 estudiantes. Se preguntó si había completado las tres dosis de vacuna contra COVID-19 y la principal razón para la aceptación o reticencia vacunal. Se realizó un análisis descriptivo, se aplicó la prueba chi cuadrado y exacta de Fisher. Resultados. El 85,5% aceptó la vacuna principalmente por no querer contagiar a familiares (38,1%) y no querer enfermarse (27,8%). El 14,5% fue reticente, especialmente por prolongados tiempos de espera en vacunatorios (37,3%) y lejanía de los centros de vacunación (13,6%). Conclusiones. En los universitarios estudiados, el temor a la enfermedad impulsó la aceptación de la vacuna contra COVID-19 y la inaccesibilidad a los servicios de salud generó la reticencia.

Introduction. University students influence their family and community decisions in favor of vaccination. Objective. To identify the main reasons for COVID-19 vaccine acceptance or hesitancy among university entrants. Methods. A cross-sectional study in a sample of 408 students. We asked whether the student had completed the three doses the COVID-19 vaccine and the main reason for vaccine acceptance or hesitancy. A descriptive analysis was performed, the chi-square test and Fisher's exact were applied. Results. 85.5% accepted vaccination mainly because they did not want to infect family members (38.1%) and did not want to get sick (27.8%). 14.5% were hesitancy especially due to long waiting times in vaccination centers (37.3%) and distance from vaccination centers (13.6%). Conclusions. In the university students studied, the fear of disease drove COVID-19 vaccine acceptance and inaccessibility to health services generated vaccine hesitancy among university entrants.

Biochemical, Catabolic, and PGP Activity of Microbial Communities and Bacterial Strains from the Root Zone of Baccharis linearis in a Mediterranean Mine Tailing.

The management of mine tailings (MT) is commonly workload heavy, intrusive, and expensive. Phytostabilization offers a promising approach for MT management; however, it poses challenges due to the unfavorable physicochemical properties of these wastes. Nevertheless, native microorganisms capable of supporting plant growth and development could enhance the efficacy of phytostabilization. This study assesses the biological activity of microbial communities from the root zone of Baccharis linearis, which is naturally present in MT, in order to evaluate their biotechnological potential for phytostabilization. The root zone and bulk samples were collected from B. linearis plants located within a MT in the Mediterranean zone of Chile. Enzyme activities related to the cycling of C, N, and P were assessed. The community-level physiological profile was evaluated using the MicroRespTM system. Bacterial plant growth-promoting (PGP) traits and colony forming units (CFU) were evaluated through qualitative and microbiological methods, respectively. CFU, enzyme activities, and CLPP were higher in the root zone compared with the bulk samples. Five bacterial strains from the root zone exhibited PGP traits such as P solubilization and N acquisition, among others. The presence of microbial communities in the root zone of B. linearis with PGP traits suggests their potential to enhance the ecological management of MT through phytostabilization programs.

Experiencia clínica de uso de Brentuximab-vedotin como terapia de linfoma de Hodgkin recaído o refractario en Hospital Guillermo Grant Benavente, Concepción, Chile

Introducción: El linfoma de Hodgkin es una neoplasia de células B de buen pronóstico, pero con mala respuesta a quimioterapia en casos refractarios o recaídas. Brentuximab vedotin es un anticuerpo monoclonal antiCD30 aprobado para su uso en estos casos. El presente trabajo tiene como objetivo describir la experiencia clínica de los pacientes tratados con brentuximab vedotin bajo la modalidad de acceso expandido. Material y Métodos: Estudio retrospectivo sobre información clínica de pacientes diagnosticados de linfoma de Hodgkin refractario o en recaída y tratados con brentuximab-vedotin en el Hospital Regional de Concepción en el período 2015-2021. Resultados: Se identificaron 7 pacientes, 5/7 de sexo masculino, con una mediana de edad de 35 años (21-50). Cinco casos fueron celularidad mixta y 2 esclerosis nodular. Cuatro estaban en etapa II, 1/7 en etapa III y 3/7 en etapa IV. La mediana de líneas de tratamiento previas fue 4 (3-5) y en 2 casos la recaída fue postrasplante. En 6/7 casos se empleó como inducción y en un caso se empleó como mantención postransplante autólogo de médula ósea. La administración fue ambulatoria por vía periférica con una mediana de dosis 150 mg y 10 ciclos. En un caso se necesitó ajuste de dosis por toxicidad. Tres de 6 pacientes lograron remisión completa y fueron a trasplante autólogo de médula ósea. Conclusiones: brentuximab vedotin es un medicamento ambulatorio de baja toxicidad que puede optimizar el tratamiento de pacientes con linfoma de Hodgkin recaído-refractario.

Introduction: Hodgkin's lymphoma is a B-cell neoplasm with a good prognosis but a poor response to chemotherapy in refractory or relapsed cases. Brentuximab-vedotin is an anti-CD30 monoclonal antibody approved for use in these cases. This study aims to describe the clinical experience of patients treated with brentuximab-vedotin through expanded access modality. Materials and Methods: A retrospective study on clinical information of patients diagnosed with refractory or relapsed Hodgkin's lymphoma treated with brentuximab-vedotin at the Regional Hospital of Concepción in the period 2015-2021. Results: 7 patients were identified, 5/7 male, with a median age of 35 years (21-50). Five cases were mixed cellularity, and two were nodular sclerosis. Four were in stage II, 1/7 in stage III, and 3/7 in stage IV. The median number of previous treatment lines was 4 (3-5), and the relapse was post-transplantation in two cases. In 6/7 cases, brentuximab-vedotin was used as induction, and in one case, it was used as post-autologous bone marrow transplant maintenance. The administration was outpatient via a peripheral route with a median dose of 150 mg and ten cycles. In one case, dose adjustment was required due to toxicity. Three out of 6 patients achieved complete remission and underwent autologous stem cell transplantation. Conclusion: brentuximab-vedotin is an outpatient medication with low toxicity that can optimize the treatment of patients with relapsed-refractory Hodgkin's lymphoma.

Características clínicas de neoplasia de células dendríticas plasmocitoides blásticas en Chile: reporte de 10 casos

Introducción: La neoplasia de células dendríticas plasmocitoides blásticas (NCDPB) es una hemopatía maligna poco frecuente y de mal pronóstico, con reportes de casos aislados en la realidad nacional. Produce compromiso cutáneo y de médula ósea y frecuentemente es confundida con otras patologías al diagnóstico. El presente trabajo tiene como objetivo describir las características clínicas de 10 pacientes diagnosticados en centros asistenciales chilenos. Material y Métodos: Se obtuvo en forma retrospectiva información clínica e inmunofenotípica de pacientes diagnosticados de NCDPB en los centros participantes en el periodo 2013-2021. Resultados: Se identificaron 10 pacientes, el 80% de sexo masculino, con una mediana de edad de 66 años (15-81). Los diagnósticos iniciales de derivación más frecuentes fueron linfoma T (4/10) y leucemia aguda mieloblástica (3/10). La mayoría presentó afección cutánea (7/10) y compromiso de médula (7/10) y en menor frecuencia adenopatías, esplenomegalia y hepatomegalia. En el hemograma se observó anemia y leucopenia, con blastos en frotis en 5/10. Se indicó CHOP en 8/10 casos con remisión en 5/8 y en un caso HyperCVAD seguido de trasplante alogénico de médula ósea. La mediana de sobrevida fue de 10 meses (IC 95% 4,2-15,8 meses) con 9/10 fallecidos. Se documentó recaída en sistema nervioso central en 2 casos. Conclusiones: La NCDPB es una patología poco frecuente que se presenta en la realidad nacional de forma similar a lo descrito en la literatura. Es susceptible de responder a quimioterapia inicial asociada a terapia intratecal.

Background: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare malignant tumor with a dismal prognosis, with isolated case reports in Chile. The BPDCN can present skin and bone marrow compromise, and its diagnosis is frequently confused with other pathologies. This study aimed to evaluate the clinical and immunophenotypical features of BPDCN in the Chilean population. Methods: We performed a retrospective study from 2013 to 2021 in clinical records of 2 public Chilean referral hospitals, including ten patients, 80% male, with a median age of 66 years (15-81). Results: The most frequent initial referral diagnoses were T-cell lymphoma (4/10) and acute myeloblastic leukemia (3/10). Seven patients presented skin and bone marrow involvement; we found a lower frequency of adenopathies (5/10), splenomegaly (2/10), and hepatomegaly (2/10). The complete blood count revealed anemia and leukopenia, with blasts in 5/10. Nine patients received induction therapy. CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) was indicated in 8/10 cases with remission in 5/8, and 1 patient received HyerCVAD (cyclophosphamide, vincristine, doxorubicin and dexamethasone, methotrexate, cytarabine) and an allogeneic bone marrow transplant. The median survival was 10 months (95% CI 4.2-15.8 months) with 9/10 deaths. Relapse in the central nervous system was documented in 2 cases. Conclusions: Our study found that BPDCN, a rare pathology in the Chilean population, shows a similar clinical presentation compared to previous studies. It is susceptible to respond to initial systemic and intrathecal chemotherapy.

Stability of Phenolic Compounds, Antioxidant Activity and Color Parameters in Colored-Flesh Potato Chips.

Potato (Solanum tuberosum) chips are the most consumed snacks worldwide today. Colored potato chips prepared from potato cultivars with red and purple flesh are a novel alternative to traditional potato chips because of their higher phenolic compound content, such as anthocyanins and hydroxycinnamic acid derivatives (HCADs), which might make these chips healthier compared with traditional chips. There is little information on the stability of these compounds. In this study, the nutritional value of these chips was evaluated by determining phenolic profiles, antioxidant activity and color parameters with liquid chromatography diode array and mass spectrometry detection (HPLC-DAD-ESI-MS/MS) and spectrophotometric methods during storage for four months. Five anthocyanins and three HCADs were detected, with the latter compounds being the most abundant, with concentrations on average between the first (97.82 mg kg-1) and the last (31.44 mg kg-1) week of storage. Similar trends were observed in antioxidant activity and stability, with the CUPRAC method showing the highest response among all the methods employed. The color indices were stable throughout the storage time. Based on these results, colored-flesh potato chips are an optimal alternative for consumption because of their high retention of phenolic compounds and antioxidant activity during storage, providing potential benefits to human health.

Role of Lateral Ankle Ligaments in Vertical Stability of the Fibula: A Cadaveric Model.

BACKGROUND: In unstable ankle fractures, the role of the deltoid and syndesmosis ligaments has been widely studied. However, it is uncertain what the importance of the lateral ankle ligament complex (LALC) is in the vertical stability of the fibula. Given its anatomical position, it should prevent the proximal translation of the fibula. This study aims to evaluate the role of the LALC in stabilizing the fibula in the vertical plane. METHODS: Eleven below-knee cadaveric specimens were used in this study. Proximal traction of the fibula was performed by applying 50 N in the intact state and after sequential transection of the syndesmotic ligaments, anterior talofibular ligament (ATFL), and the calcaneofibular ligament (CFL). At each stage, the proximal displacement of the fibula was measured. One-way repeated measures analysis of variance with post hoc Bonferroni correction was carried out to determine any significant differences between the groups. A P value <.05 was considered statistically significant. RESULTS: The vertical displacement of the fibula in the intact state, and after sequential transection of syndesmotic ligaments, ATFL, and CFL was 1.96 ± 1.19 mm, 3.96 ± 1.33 mm, 5.9 ± 1.73 mm, and 10.22 ± 2.76 mm, respectively. There was no significant difference in the proximal displacement of the fibula between the intact and the syndesmotic ligaments groups (P < .05). However, when the syndesmotic ligaments were transected in conjunction with ATFL ± CFL, a significant difference was observed compared to the intact state (P < .001). CONCLUSION: The complete disruption of syndesmotic ligaments did not significantly increase the proximal displacement of the fibula. However, when the ATFL ± CFL were additionally disrupted, there was a significant increase in the vertical translation of the fibula. CLINICAL RELEVANCE: To our knowledge, this is the first study describing that LALC plays a paramount role in the vertical stability of the fibula. Concomitant syndesmosis and LALC should be suspected in an axially unstable fibular fracture with a significant proximal displacement.

Flow cytometry-detected changes in megaloblastic anemia secondary to cobalamin deficiency.

Introduction: Megaloblastic anemias secondary to Vitamin B12 deficiency are a group of pathologies produced by defective nuclear DNA synthesis. Objective: To describe the maturation alterations found in hematopoietic precursors of the bone marrow in a series of patients with megaloblastic anemia. Methods: Were included patients attended at the Regional Hospital of Concepción with bone marrow samples sent for the study of cytopenia by flow cytometry whose final diagnosis was megaloblastic anemia. The immunophenotype was performed with CD45, CD34, CD117, HLA-DR, markers of neutrophil (CD13, CD11b, CD10, CD16) and/or erythroblast (CD105, CD71, CD36) maturation. Results: From the flow cytometry laboratory database, 8 patients with megaloblastic anemia were identified, and myelodysplastic syndromes (n=9) and normal or reactive bone marrow (n=10) were used as controls. 44% were men, with a median age of 58 years. Megaloblastic anemia was associated with a higher proportion of size and complexity of erythroid and myeloid progenitors compared to lymphocytes compared to controls. The total percentage of erythroblasts and the proportion of CD34+ myeloid cells associated with erythroid lineage was higher in megaloblastic anemia, associated with a maturation arrest in the CD105+ precursor stage (69% vs 19% and 23%, p<0.001). The heterogeneity of CD36 and CD71 in megaloblastic anemia was similar to myelodysplastic syndromes. Conclusions: Megaloblastic anemia produces a heterogeneous involvement of hematopoiesis, characterized by a greater size and cellular complexity of precursors of the neutrophil and erythroid series and a maturation arrest of the erythroblasts.

Introducción: Anemias megaloblásticas secundarias a la deficiencia de vitamina B12 son patologías producidas por una síntesis defectuosa del ADN nuclear. Objetivo: Describir las alteraciones madurativas encontradas en precursores hematopoyéticos de la médula ósea de una serie de pacientes con anemia megaloblástica. Métodos: Se incluyeron pacientes atendidos en el Hospital Regional de Concepción con muestras de médula ósea enviadas para estudio de citopenias por citometría de flujo cuyo diagnóstico fue anemia megaloblástica. El inmunofenotipo se realizó con CD45, CD34, CD117, HLA-DR, marcadores de maduración de serie de neutrófilo (CD13, CD11b, CD10, CD16) y/o eritroblasto (CD105, CD71, CD36). Resultados: Se identificaron 8 pacientes con anemia megaloblástica y como controles se utilizaron síndromes mielodisplásicos (n=9) y médula ósea normal o reactiva (n=10). El 44% eran hombres, con una mediana de edad de 58 años. La anemia megaloblástica se asoció con una mayor proporción de tamaño y complejidad de progenitores eritroides y mieloides con respecto de los linfocitos en comparación a los controles. El porcentaje total de eritroblastos y la proporción de células mieloides CD34+ comprometidas con el linaje eritroide fue mayor en anemia megaloblástica, asociado a una parada madurativa en la etapa de precursor CD105+ (69% vs 19% y 23%, p <0.001). La heterogeneidad de CD36 y CD71 en anemia megaloblástica fue similar a los síndromes mielodisplásicos. Conclusiones: la anemia megaloblástica produce una afectación heterogénea de la hematopoyesis, caracterizada por un mayor tamaño y complejidad celulares de precursores de la serie neutrófilo y eritroide y una detención madurativa de los eritroblastos.

Flow cytometry-detected changes in megaloblastic anemia secondary to cobalamin deficiency

Introduction: Megaloblastic anemias secondary to Vitamin B12 deficiency are a group of pathologies produced by defective nuclear DNA synthesis. Objective: To describe the maturation alterations found in hematopoietic precursors of the bone marrow in a series of patients with megaloblastic anemia. Methods: Were included patients attended at the Regional Hospital of Concepción with bone marrow samples sent for the study of cytopenia by flow cytometry whose final diagnosis was megaloblastic anemia. The immunophenotype was performed with CD45, CD34, CD117, HLA-DR, markers of neutrophil (CD13, CD11b, CD10, CD16) and/or erythroblast (CD105, CD71, CD36) maturation. Results: From the flow cytometry laboratory database, 8 patients with megaloblastic anemia were identified, and myelodysplastic syndromes (n=9) and normal or reactive bone marrow (n=10) were used as controls. 44% were men, with a median age of 58 years. Megaloblastic anemia was associated with a higher proportion of size and complexity of erythroid and myeloid progenitors compared to lymphocytes compared to controls. The total percentage of erythroblasts and the proportion of CD34+ myeloid cells associated with erythroid lineage was higher in megaloblastic anemia, associated with a maturation arrest in the CD105+ precursor stage (69% vs 19% and 23%, p<0.001). The heterogeneity of CD36 and CD71 in megaloblastic anemia was similar to myelodysplastic syndromes. Conclusions: Megaloblastic anemia produces a heterogeneous involvement of hematopoiesis, characterized by a greater size and cellular complexity of precursors of the neutrophil and erythroid series and a maturation arrest of the erythroblasts.

Introducción: Anemias megaloblásticas secundarias a la deficiencia de vitamina B12 son patologías producidas por una síntesis defectuosa del ADN nuclear. Objetivo: Describir las alteraciones madurativas encontradas en precursores hematopoyéticos de la médula ósea de una serie de pacientes con anemia megaloblástica. Métodos: Se incluyeron pacientes atendidos en el Hospital Regional de Concepción con muestras de médula ósea enviadas para estudio de citopenias por citometría de flujo cuyo diagnóstico fue anemia megaloblástica. El inmunofenotipo se realizó con CD45, CD34, CD117, HLA-DR, marcadores de maduración de serie de neutrófilo (CD13, CD11b, CD10, CD16) y/o eritroblasto (CD105, CD71, CD36). Resultados: Se identificaron 8 pacientes con anemia megaloblástica y como controles se utilizaron síndromes mielodisplásicos (n=9) y médula ósea normal o reactiva (n=10). El 44% eran hombres, con una mediana de edad de 58 años. La anemia megaloblástica se asoció con una mayor proporción de tamaño y complejidad de progenitores eritroides y mieloides con respecto de los linfocitos en comparación a los controles. El porcentaje total de eritroblastos y la proporción de células mieloides CD34+ comprometidas con el linaje eritroide fue mayor en anemia megaloblástica, asociado a una parada madurativa en la etapa de precursor CD105+ (69% vs 19% y 23%, p <0.001). La heterogeneidad de CD36 y CD71 en anemia megaloblástica fue similar a los síndromes mielodisplásicos. Conclusiones: la anemia megaloblástica produce una afectación heterogénea de la hematopoyesis, caracterizada por un mayor tamaño y complejidad celulares de precursores de la serie neutrófilo y eritroide y una detención madurativa de los eritroblastos.

Rendimiento Biomecánico de las Placas de Tibia Proximal Utilizadas en Fracturas de Platillos Tibiales evaluado a través de Modelos de Elementos Finitos: Protocolo de Revisión Sistemática / A systematic Review Protocol Examining the Biomechanical Performance of Proximal Tibial Plates used in Tibial Plate Fractures assessed by Finite Element Analysis

Objetivo. Analizar el rendimiento biomecánico de las placas de tibia proximal utilizadas en fracturas de platillos tibiales evaluado a través de modelos de elementos finitos. Métodos. Se realizará una búsqueda exhaustiva en PubMed/Medline, Embase, Lilacs, Web of Science y Google Scholar. No se utilizará ninguna restricción de idioma o estado de publicación. Dos revisores examinarán de forma independiente los posibles artículos elegibles, de acuerdo con los criterios de selección predefinidos. Se incluirán los estudios que evalúen el rendimiento de los platillos tibiales proximales utilizados en las fracturas del platillo tibial evaluadas mediante el análisis de elementos finitos. La extracción de datos sobre las características del estudio, los métodos, los resultados y la evaluación del riesgo de sesgo se realizará mediante un formulario estandarizado. Considerando el diseño de estudio no se requiere evaluación por comité de ética. Los resultados de esta revisión se difundirán a través de la publicación en revistas revisadas por pares, redes sociales y congresos de la especialidad. Se espera que los resultados de esta revisión permitan optimizar los resultados del manejo quirúrgico de las fracturas de platillos tibiales. Número de registro PROSPERO: CRD42023396015.

Objetive. To analyze the biomechanical performance of proximal tibial plates used in tibial plate fractures evaluated through finite element modeling. Methods. A comprehensive search will be conducted in PubMed/Medline, Embase, Lilacs, Web of Science, and Google Scholar. No language or publication status restrictions will be used. Two reviewers will independently review potential eligible articles according to predefined selection criteria. Studies evaluating the performance of proximal tibial splints used in tibial splint fractures assessed by finite element analysis will be included. Data extraction on study characteristics, methods, results, and risk of bias assessment will be performed using a standardized form. Considering the study design, evaluation by an ethics committee is not required. The results of this review will be disseminated through publication in peer-reviewed journals, social networks and specialty congresses. It is expected that the results of this review will allow optimizing the results of the surgical management of tibial plate fractures. PROSPERO registration number: CRD42023396015.

The Reverse Shoulder Arthroplasty Angle in MRI: Impact of the Articular Cartilage in the Estimated Inclination of the Inferior Glenoid.

Purpose: To describe the reverse shoulder arthroplasty angle (RSA angle) in magnetic resonance imaging (MRI) and compare the angle formed using bony landmarks (Bony RSA angle or B-RSA angle) with another angle formed using the cartilage margin as reference (Cartilage RSA angle or C-RSA angle). Methods: Adult patients with a shoulder MRI obtained in our hospital between July 2020 and July 2021 were included. The C-RSA angle and B-RSA angle were measured. All images were independently assessed by 4 evaluators. Intraclass correlation coefficient (ICC) was determined for the B-RSA and C-RSA to evaluate interobserver agreement. Results: A total of 61 patients were included with a median age of 59 years (17-77). C-RSA angle was significantly higher than B-RSA (25.4° ± 0.7 vs 19.5° ± 0.7, respectively) with a P-value <.001. The overall agreement was considered "good" for C-RSA (ICC = 0.74 [95% CI 0.61-0.83]) and "excellent" for B-RSA angle (ICC = 0.76 [95% CI 0.65-0.85]). Conclusions: C-RSA angle is significantly higher than B-RSA angle. In cases without significant glenoid wear neglecting to account for the remaining articular cartilage at the inferior glenoid margin may result in superior inclination of standard surgical guides.

The Reliability of Acromioclavicular Joint Dislocation Classification Systems: A Comparison Between the Rockwood and Kraus Classifications.

Background: The Rockwood system for the classification of acute acromioclavicular (AC) joint dislocations has been associated with a lack of reliability. A novel system has been proposed (Kraus classification) that is based on dynamic posterior translation of these injuries. Purpose: To assess the interobserver and intraobserver reliability of the Rockwood and Kraus classification systems and also to examine the impact of surgeon experience on the assessments. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: Included were 45 patients with acute AC joint injuries who underwent a radiographic examination using standard bilateral AP and modified Alexander views. For interobserver reliability, 6 shoulder surgeons (expert group) and 6 orthopaedic residents (novice group) reviewed the radiographs to classify injuries according to the Rockwood and Kraus classifications; for each categorization, the participants chose between nonoperative management and surgical treatment. The evaluation was repeated 6 weeks later to determine intraobserver reliability. Kappa (κ) coefficients and their 95% CIs were used to compare interobserver and intraobserver reliability for each classification system according to assessor experience. Statistical differences were considered significant when the upper and lower boundaries of the 95% CI did not overlap. Results: The overall interobserver agreement for diagnosis (both novice and expert groups) was moderate (κ = 0.52 [95% CI, 0.51-0.54]) for the Rockwood classification and substantial (κ = 0.62 [95% CI, 0.53-0.65]) for the Kraus classification; however, no significant differences were observed between the κ values. The overall interobserver agreement for treatment selection was substantial when using both the Rockwood (κ = 0.78 [95% CI, 0.72-0.81]) and Kraus (κ = 0.77 [95% CI, 0.66-0.87]) classifications. The overall intraobserver agreement for diagnosis was substantial using both the Rockwood (κ = 0.65 [95% CI, 0.61-0.67]) and Kraus (κ = 0.73 [95% CI, 0.69-0.75]) classifications. There were no significant differences between the novice and expert groups on any of the evaluations. Conclusion: The Kraus system was slightly more reliable than the Rockwood system for classifying AC joint injuries both between assessor groups and overall. The level of surgeon experience had no impact on the evaluations.

An independent inter- and intra-observer agreement assessment of the AOSpine upper cervical injury classification system.

BACKGROUND CONTEXT: The complex anatomy of the upper cervical spine resulted in numerous separate classification systems of upper cervical spine trauma. The AOSpine upper cervical classification system (UCCS) was recently described; however, an independent agreement assessment has not been performed. PURPOSE: To perform an independent evaluation of the AOSpine UCCS. STUDY DESIGN: Agreement study. PATIENT SAMPLE: Eighty-four patients with upper cervical spine injuries. OUTCOME MEASURES: Inter-observer agreement; intra-observer agreement. METHODS: Complete imaging studies of 84 patients with upper cervical spine injuries, including all morphological types of injuries defined by the AOSpine UCCS were selected and classified by six evaluators (from three different countries). The 84 cases were presented to the same raters randomly after a 4-week interval for repeat evaluation. The Kappa coefficient (κ) was used to determine inter- and intra-observer agreement. RESULTS: The interobserver agreement was almost perfect when considering the fracture site (I, II or III), with κ=0.82 (0.78-0.83), but the agreement according to the site and type level was moderate, κ=0.57 (0.55-0.65). The intra-observer agreement was almost perfect considering the injury, with κ=0.83 (0.78-0.86), while according to site and type was substantial, κ=0.69 (0.67-0.71). CONCLUSIONS: We observed only a moderate inter-observer agreement using this classification. We believe our results can be explained because this classification attempted to organize many different injury types into a single scheme.

[Clinical experience of using brentuximab-vedotin as therapy in relapsed/refractory Hodgkin's lymphoma at Hospital Guillermo Grant Benavente, Concepción, Chile]. / Experiencia clínica de uso de Brentuximab-vedotin como terapia de linfoma de Hodgkin recaído o refractario en Hospital Guillermo Grant Benavente, Concepción, Chile.

INTRODUCTION: Hodgkin's lymphoma is a B-cell neoplasm with a good prognosis but a poor response to chemotherapy in refractory or relapsed cases. Brentuximab-vedotin is an anti-CD30 monoclonal antibody approved for use in these cases. This study aims to describe the clinical experience of patients treated with brentuximab-vedotin through expanded access modality. MATERIALS AND METHODS: A retrospective study on clinical information of patients diagnosed with refractory or relapsed Hodgkin's lymphoma treated with brentuximab-vedotin at the Regional Hospital of Concepción in the period 2015-2021. RESULTS: 7 patients were identified, 5/7 male, with a median age of 35 years (21-50). Five cases were mixed cellularity, and two were nodular sclerosis. Four were in stage II, 1/7 in stage III, and 3/7 in stage IV. The median number of previous treatment lines was 4 (3-5), and the relapse was post-transplantation in two cases. In 6/7 cases, brentuximab-vedotin was used as induction, and in one case, it was used as post-autologous bone marrow transplant maintenance. The administration was outpatient via a peripheral route with a median dose of 150 mg and ten cycles. In one case, dose adjustment was required due to toxicity. Three out of 6 patients achieved complete remission and underwent autologous stem cell transplantation. CONCLUSION: brentuximab-vedotin is an outpatient medication with low toxicity that can optimize the treatment of patients with relapsed-refractory Hodgkin's lymphoma.

[Clinical features of blastic plasmacytoid dendritic neoplasm in Chile: report of 10 cases]. / Características clínicas de neoplasia de células dendríticas plasmocitoides blásticas en Chile: reporte de 10 casos.

BACKGROUND: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare malignant tumor with a dismal prognosis, with isolated case reports in Chile. The BPDCN can present skin and bone marrow compromise, and its diagnosis is frequently confused with other pathologies. This study aimed to evaluate the clinical and immunophenotypical features of BPDCN in the Chilean population. METHODS: We performed a retrospective study from 2013 to 2021 in clinical records of 2 public Chilean referral hospitals, including ten patients, 80% male, with a median age of 66 years (15-81). RESULTS: The most frequent initial referral diagnoses were T-cell lymphoma (4/10) and acute myeloblastic leukemia (3/10). Seven patients presented skin and bone marrow involvement; we found a lower frequency of adenopathies (5/10), splenomegaly (2/10), and hepatomegaly (2/10). The complete blood count revealed anemia and leukopenia, with blasts in 5/10. Nine patients received induction therapy. CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) was indicated in 8/10 cases with remission in 5/8, and 1 patient received HyerCVAD (cyclophosphamide, vincristine, doxorubicin and dexamethasone, methotrexate, cytarabine) and an allogeneic bone marrow transplant. The median survival was 10 months (95% CI 4.2-15.8 months) with 9/10 deaths. Relapse in the central nervous system was documented in 2 cases. CONCLUSIONS: Our study found that BPDCN, a rare pathology in the Chilean population, shows a similar clinical presentation compared to previous studies. It is susceptible to respond to initial systemic and intrathecal chemotherapy.

No Más Fracturas - Implementación de la primera Unidad de Coordinación de Fracturas en Chile: experiencia al año de funcionamiento / Implementation of a fracture liaison service. Experience with 177 patients

BACKGROUND: Every year about 9 million fragility fractures (FF) occur worldwide and 80% of these are underdiagnosed or undertreated. Aiming to close the gap of diagnosis and treatment of osteoporosis, Fracture Liaison Services (FLS) were developed. AIM: To describe the implementation of the first FLS in Chile, its inclusion criteria, patient enrolment, treatment adherence and referrals during the first year. MATERIAL AND METHODS: A FLS was implemented at a health care network composed by two hospitals. The International Osteoporosis Foundation (IOF) guidelines were applied with a nurse practitioner as the coordinator. From May 2020 to April 2021 all patients diagnosed with a FF in the emergency rooms were invited to participate. Patients with pathological fractures and active cancer were excluded. Demographical data, fracture location, previous fractures, treatment and adherence, and mortality were recorded. RESULTS: From 443 patients with a diagnosis of FF, 177 patients (40%) accepted to participate. Their mean age was 74 ± 13 years and 84% (149) were female. Forty eight percent (84) had a lower extremity FF. Hip fractures were the most common (67). Ninety-five patients reported previous FF and 11,2% (20) had received anti-osteoporotic treatment. At four months of follow-up, 62% (50) had received vitamin D and calcium supplementation and 20% (16) of those patients with an indication of anti-osteoporotic drugs, had received them. CONCLUSIONS: The implementation of the FLS was successful with a 40% enrolment of patients, receiving certification by the IOF.