Successful prophylactic measures for the eradication of Staphylococcus aureus infections in elective hip primary and revision arthroplasty.

INTRODUCTION: Staphylococcus aureus stands as the predominant etiological agent in postoperative acute prosthetic joint infections (PJI), contributing to 35-50% of reported cases. This study aimed to evaluate the efficacy of dual prophylaxis incorporating cefuroxime and teicoplanin, in combination with nasal decolonization utilizing 70% alcohol, and oral and body lavage with chlorhexidine. MATERIAL AND METHODS: We conducted a retrospective review of electronic health records regarding primary and revision arthroplasties conducted at our institution from 2020 to 2021. Relevant variables linked to prosthetic joint infections (PJI) were documented until the latest follow-up. RESULTS: A total of 539 operations (447 primary arthroplasties and 92 revision arthroplasties) were performed on 519 patients. There were 11 cases of postoperative acute PJI, resulting in infection rates of 1.6% for primary arthroplasties and 4.3% for revision surgeries. Infections were more prevalent in male patients, individuals with an ASA classification>II, and those undergoing longer operations (>90min). S. aureus was not isolated in any of the cases. CONCLUSION: The prophylactic measures implemented in our institution have exhibited a high efficacy in preventing postoperative acute PJI caused by S. aureus.

Risk factors for complications in total hip arthroplasty. / Factores de riesgo para complicaciones en artroplastia total de cadera.

INTRODUCTION AND OBJECTIVE: Hip arthroplasty represents a significant advancement in the treatment of refractory chronic joint pain, improving quality of life and functionality. The objective of this study is to identify the risk factors associated with local and systemic complications in patients treated with total hip arthroplasty. METHODS: Observational, analytical, retrospective cohort study, which included 304 participants treated with total hip replacement. Comparison of variables between two groups was performed; 38 participants in the group with complications and 266 participants in the group without complications. RESULTS: The mean age in the complication group was 66 years (SD 18.7) and in the uncomplicated group it was 67,1 years (SD 15.1) (p 0,686). Female sex was observed in 73.3% of the group with complications and 65% in the group without complications. (p 0.292). Risk factors were: hip fracture as an indication for arthroplasty RR 1.33 [95% CI 1.004;1.775 p 0.047], coronary heart disease RR 1.31 [95% CI 1.067;1.616 p 0.010] and surgical bleeding equal to or greater than 400 cc RR 1.11 [95% CI 1.012;1.218 p 0.028]. CONCLUSIONS: The risk factors for complications in total hip arthroplasty were: hip fracture as the indication for arthroplasty, coronary artery disease, and surgical bleeding equal to or greater than 400 cc.

Effect of hip hemiarthroplasty dislocation on mortality after hip fracture surgery. / [Artículo traducido] Efecto de la luxación de la prótesis parcial de cadera en la mortalidad tras la cirugía de fractura de cadera.

INTRODUCTION: Hip arthroplasty is the treatment of choice for displaced femoral neck fractures among the older population. The hip prosthesis dislocation is one of the most pointed potential complications after hip arthroplasty, but there is a lack of updated information on the effect of dislocation on the survival of older hip fracture patients so treated by hip hemiarthroplasty. We aim to evaluate the standalone effect of hip prosthesis dislocation after hip fracture hemiarthroplasty on patients' survival outcomes. MATERIALS AND METHODS: We conducted a retrospective multicenter study, including 6631 femoral neck fracture patients over 65 surgically treated by hemiarthroplasty. We made follow-up cut-offs 30-days, 6 weeks, 90-days, and one year after hospital discharge determining hip dislocation rate and patients' survival. RESULTS: The women population represented 78.7%, and the mean age of the population was 85.2 ± 6.7 years. Hip prosthesis dislocation incidence was 1.9% in the first 90-days after discharge, representing 91.54% of primary dislocations yearly noted. We reported statistically significant increased mortality rates of patients presenting at least one hip prosthesis dislocation event (from 16.0% to 24.6% at 90-day after discharge, and 29.5% to 44.7% at one year), and also significantly decreasing patient survival function at 90-day (P = .016) and one-year follow-up (P < .001). The recurrent dislocation events (26.15%) showed even higher mortality rates (up to 60.6%, p < .001). The multivariate Cox regression model determined that prosthesis dislocation was the only significant variable (P = .035) affecting patient survival, increasing the risk of dying before one year of follow-up by 2.7 times. DISCUSSION: Our study stands for the standalone hip prosthesis dislocation entailing a higher risk of death after hip fracture hemiarthroplasty in the older population.

Effect of hip hemiarthroplasty dislocation on mortality after hip fracture surgery.

INTRODUCTION: Hip arthroplasty is the treatment of choice for displaced femoral neck fractures among the older population. The hip prosthesis dislocation is one of the most pointed potential complications after hip arthroplasty, but there is a lack of updated information on the effect of dislocation on the survival of older hip fracture patients so treated by hip hemiarthroplasty. We aim to evaluate the standalone effect of hip prosthesis dislocation after hip fracture hemiarthroplasty on patients' survival outcomes. MATERIALS AND METHODS: We conducted a retrospective multicenter study, including 6631 femoral neck fracture patients over 65 surgically treated by hemiarthroplasty. We made follow-up cut-offs 30-days, 6 weeks, 90-days, and one year after hospital discharge determining hip dislocation rate and patients' survival. RESULTS: The women population represented 78.7%, and the mean age of the population was 85.2±6.7 years. Hip prosthesis dislocation incidence was 1.9% in the first 90-days after discharge, representing 91.54% of primary dislocations yearly noted. We reported statistically significant increased mortality rates of patients presenting at least one hip prosthesis dislocation event (from 16.0% to 24.6% at 90-day after discharge, and 29.5% to 44.7% at one year), and also significantly decreasing patient survival function at 90-day (p=0.016) and one-year follow-up (p<0.001). The recurrent dislocation events (26.15%) showed even higher mortality rates (up to 60.6%, p<0.001). The multivariate Cox regression model determined that prosthesis dislocation was the only significant variable (p=0.035) affecting patient survival, increasing the risk of dying before one year of follow-up by 2.7 times. DISCUSSION: Our study stands for the standalone hip prosthesis dislocation entailing a higher risk of death after hip fracture hemiarthroplasty in the older population.

Copa de doble movilidad: aciertos, riesgos y enseñanzas / Dual mobility cup: successes, risks and lessons learned

Resumen: Se hace una revisión narrativa del desarrollo y evolución hasta el momento de las copas de doble movilidad enfocada en sus aciertos, fallas y enseñanzas. Se mencionan las herramientas con las cuales contamos para prevenir y en su caso, tratar la luxación protésica de cadera y los principales problemas que presentan. El principal objetivo de esta publicación es hacer reflexiones y comentarios en cuanto a lo que debemos estar atentos ante un mundo de diseños que actualmente existen en el mercado con una diversidad de diseños, materiales, aleaciones, tipos de polietileno, etc. Se analizan los problemas que enfrentan algunos modelos para obtener una fijación estable a largo plazo, el problema que posiblemente representan los diferentes modelos contemporáneos de doble movilidad y sus resultados clínicos. Se discuten y comentan los puntos anteriores y se establecen conclusiones y recomendaciones.

Abstract: A narrative review of the development and evolution to date of the double mobility cups is made, focusing on their successes, failures and teachings. The tools with which we have to prevent and treat prosthetic hip dislocation and the main problems are mentioned. The main objective of this publication is to make reflections and comments about what we should be attentive to in a world of designs that currently exist in the market with a diversity of designs, materials, alloys, types of polyethylene, etc. Some models are found to obtain a stable long-term fixation, the problem that potentially represents the different contemporary models of double mobility and their clinical results. The previous points are discussed and commented and conclusions and recommendations were reached.

Economic impact of periprosthetic hip fractures. / [Artículo traducido] Impacto económico de las fracturas periprotésicas de cadera.

INTRODUCTION: Hip replacement is one of the most successful operations in orthopaedic surgery. Periprosthetic hip fractures (PPHF) have very serious consequences for the patient, and they also entail a very important economic impact on healthcare systems. The aim of the study was to provide the first detailed cost analysis of PPHF in a traumatology and orthopaedics service in a third level hospital in Spain. METHODS: The study included all patients admitted between 2009 and 2019 with a diagnosis of «PPHF¼. We assessed hospital stay cost, total cost of the operating theatre, cost of the implants used, analyses, consultations with other specialists, rehabilitation sessions, radiological tests, microbiology, blood transfusions and other surgical operations during the same admission. RESULTS: Seventy-eight patients were included in the study, 49 women and 29 men, with a mean age of 78.74 years (R 45-92). Sixty-nine patients received surgical treatment, 75% had open reduction and internal fixation (ORIF), and 25% had revision surgery. The total cost was €1 139 650.17. The average cost was €14 610.90. Significantly higher costs were incurred for revision compared to ORIF treatments, admissions that lasted more than 30 days, and patients who required more than one operation during admission. The most costly factors were the hospital stay (46%), the cost of the surgery itself (35%), and the implants (24%). CONCLUSIONS: Revision arthroplasty versus ORIF treatment, admissions lasting more than 30 days, and patients requiring more than one operation on admission incurred significantly higher costs. The average cost, from a hospital perspective, generated by a PPHF was €14 610.90. The most costly factors were, in descending order, the hospital stay, the cost of the surgery itself, and the implants. It is necessary to establish protocols and updated therapeutic algorithms in the perioperative management of PPHF in order to reduce both morbidity rates and associated costs.

Results of the short neck-retaining stem prostheses CFP with a minimum follow-up of 10 years. / Resultado del vástago corto con preservación del cuello femoral CFP con un seguimiento mínimo de 10 años.

BACKGROUND AND OBJECTIVE: Bone-preserving implants in primary total hip arthroplasty have become an increasingly popular treatment choice, especially short stems. Currently there are many models with morphological and biodynamic differences, among which stand out the neck-retaining systems, but there are not many studies with a long-term follow-up of these systems. The objective of this study is to retrospectively analyze the results of the Collum Femoris Preserving (CFP) short neck-retaining stem system with a minimum follow-up of 10 years. MATERIAL AND METHODS: Between 2001 and 2010, 175 prostheses with a CFP stem were performed in 157 patients in our hospital. All patients were operated on by a single surgeon. The mean age at the time of surgery was 56.47 years (range 22-77). RESULTS: 175 prostheses have been evaluated with a minimum follow-up of 10 years and a mean of 13.89 years (range 10-19), with 16 cases having been lost. During the follow-up there were 8 polyethylene replacements, 2 cup replacements due to loosening, 2 osteosynthesis due to fracture without loosening, and 5 stem replacements: 1 due to chronic infection, 2 due to fracture and 2 due to aseptic loosening. CONCLUSIONS: As far as we know, this is the first follow-up work on a short stem implanted in our country with a minimum of 10 years of follow-up. The replacement of this stem due to aseptic loosening has been 2/159 and, therefore, survival for this reason is 98.75% at 10 years.

Economic impact of periprosthetic hip fractures.

INTRODUCTION: Hip replacement is one of the most successful operations in orthopaedic surgery. Periprosthetic hip fractures (PPHF) have very serious consequences for the patient, and they also entail a very important economic impact on healthcare systems. The aim of the study was to provide the first detailed cost analysis of PPHF in a traumatology and orthopaedics service in a third level hospital in Spain. METHODS: The study included all patients admitted between 2009 and 2019 with a diagnosis of "PPHF". We assessed hospital stay cost, total cost of the operating theatre, cost of the implants used, analyses, consultations with other specialists, rehabilitation sessions, radiological tests, microbiology, blood transfusions and other surgical operations during the same admission. RESULTS: 78 patients were included in the study, 49 women and 29 men, with a mean age of 78.74 years (R 45-92). 69 patients received surgical treatment, 75% had open reduction and internal fixation (ORIF), and 25% had revision surgery. The total cost was €1,139,650.17. The average cost was €14,610.90. Significantly higher costs were incurred for revision compared to ORIF treatments, admissions that lasted more than 30 days, and patients who required more than one operation during admission. The most costly factors were the hospital stay (46%), the cost of the surgery itself (35%), and the implants (24%). CONCLUSIONS: Revision arthroplasty versus ORIF treatment, admissions lasting more than 30 days, and patients requiring more than one operation on admission incurred significantly higher costs. The average cost, from a hospital perspective, generated by a PPHF was €14,610.90. The most costly factors were, in descending order, the hospital stay, the cost of the surgery itself, and the implants. It is necessary to establish protocols and updated therapeutic algorithms in the perioperative management of PPHF in order to reduce both morbidity rates and associated costs.

Stratified cost-utility analysis of total hip arthroplasty in displaced femoral neck fracture.

OBJECTIVE: To conduct a stratified cost-utility analysis of total versus partial hip arthroplasty as a function of clinical subtype. METHOD: All cases of this type of intervention were analysed between 2010 and 2016 in the Basque Health Service, gathering data on clinical outcomes and resource use to calculate the cost and utility in quality-adjusted life years (QALYs) at individual level. The statistical analysis included applying the propensity score to balance the groups, and seemingly unrelated regression models to calculate the incremental cost-utility ratio and plot the cost-effectiveness plane. The interaction between age group and American Society of Anesthesiologists (ASA) risk class was assessed in the multivariate analysis. RESULTS: The study identified 5867 patients diagnosed with femoral neck fracture, of whom 1307 and 4560 were treated with total and partial hip arthroplasty, respectively. In the cost-utility analysis based on the seemingly unrelated regression, total hip arthroplasty was found to have a higher cost and higher utility (2465€ and 0.42 QALYs). Considering a willingness-to-pay threshold of €22,000 per QALY, total hip arthroplasty was cost-effective in the under-80-year-old subgroup. Among patients above this age, hemiarthroplasty was cost-effective in ASA class I-II patients and dominant in ASA class III-IV patients. CONCLUSIONS: Subgroup analysis supports current daily clinical practice in displaced femoral neck fractures, namely, using partial replacement in most patients and reserving total replacement for younger patients.

Evaluation of the learning curve and initial outcomes with a short cervicometaphyseal fixation stem: A case series. / Evaluación de la curva de aprendizaje y resultados iniciales con un vástago corto de fijación cervicometafisaria: Una serie de casos.

INTRODUCTION: Total hip arthroplasty in young patients has evolved in recent decades, and the use of short stems in young adult patients has been gaining popularity. The restitution of the biomechanics of the hip is a primary requirement to determine the future success of total hip replacement, and even more so in young adults who present the particularity of having a high functional demand and a long life expectancy. OBJECTIVE: The aim of this prospective study was to evaluate the learning curve and initial clinical-radiological outcomes of the Alteon Neck Preserving Stem™ (ANPS) (Exactech, Gainesville, FL, USA) with a minimum of 2 years follow up. MATERIAL AND METHODS: We conducted a multicenter prospective study that analyzed 90 consecutive total hip replacements during 2014. We performed a clinical-radiological analysis measuring Harris Hip Score (HHS), subjective Rodes and Maudsley satisfaction evaluation, radiolucencies, components position, limb length discrepancy, heterotopic ossification, medical and surgical complications and learning curve. RESULTS: During the first 30 cases, the intraoperative complication rate was 16%, while in the next 60 cases no intraoperative complications were reported. Thigh pain was reported in 3 cases (3.3%), being 2 moderates, and 1 severe. In 2 cases subsidences of 3 mm were detected in the first scheduled X-ray, both related to intraoperative fractures with no progression after 3 months. Mean HHS improved from 42.9 points (range 37-54 points) preoperatively to 93.2 on average (range, 87-96) at the end of the follow up (p < 0.01). Subjective evaluation was excellent in 75 (83.3%) cases and good in 15 patients (16.6%). CONCLUSIONS: This short stem has good clinical radiological results in a short and medium term follow-up and in the hands of surgeons specializing in arthroplasty the learning curve is estimated to be less than 30 surgeries.

Prevalencia de fracturas periprotésicas de fémur en una serie determinada de pacientes con reemplazo de cadera / Prevalence of periprosthetic femoral fractures in a selected series of hip replacement patients

Objetivo Determinar la prevalencia de fracturas periprotésicas en pacientes con antecedente de reemplazo de cadera que ingresaron a un servicio de ortopedia entre el 2010 al 2018. Materiales y métodos 709 pacientes fueron atendidos, pero solo 15 pacientes presentaron fracturas periprotésicas. Resultados La prevalencia de fracturas periprotésicas fue del 2.1% (IC 95%: 1.05; 3.17). La mayor parte de los casos se presentaron en el sexo femenino con un porcentaje de 53,3%, con edad promedio de 74.2 año. Las principales causas de fractura periprotésica fueron el trauma en la cadera por caída desde su propia altura. Solo el 12.12% presentaron alguna complicación local o sistémica. Conclusiones La prevalencia de fracturas periprotésicas fue menor del 3%; esta patología depende de distintos factores que se deben tener en cuenta al momento de realizar los procedimientos quirúrgicos.

Objective To determine the prevalence of periprosthetic fractures in patients with a history of hip replacement admitted to an orthopedic service between 2010 and 2018. Materials and methods 709 patients were seen, but only 15 patients had periprosthetic fractures. Results The prevalence of periprotic fractures was 2.1% (95% CI: 1.05; 3.17). The majority of cases occurred in females with a percentage of 53.3%, with an average age of 74.2 years. The main causes of periprotic fracture were hip trauma from falling from its own height. Only 12.12% presented some local or systemic complication. Conclusions The prevalence of periprosthetic fractures was less than 3%; this pathology depends on different factors that must be taken into account when performing surgical procedures.

Intervalos de tempo para processamento de materiais consignados de prótese total de quadril / Processing time of loaner items for total hip replacement / Intervalos de tiempo para el procesamiento de materiales consignados para prótesis total de cadera

Objetivo: Estimar os intervalos de tempo envolvidos no reprocessamento de materiais consignados temporários de prótese total de quadril em um centro de material e esterilização de um hospital privado de São Paulo (SP). Método: Estudo exploratório-descritivo, de campo, com abordagem quantitativa. A amostra foi composta de 41 processamentos de materiais consignados. Os intervalos de tempo foram registrados com auxílio de cronômetro digital, hora inicial e final de cada atividade. O cálculo amostral foi estimado com intervalo de confiança de 95%. Resultados: O tempo total do processamento teve mediana de 10 horas, o tempo efe-tivo total foi de 4,9 horas e o intervalo de tempo entre o fim do reprocessamento e o horário da cirurgia foi de 4,7 horas de antecedência. Houve cancelamento de uma cirurgia em virtude do atraso na entrega do material. Conclusão: Nesta pesquisa foram mensurados os tempos de reprocessamento de materiais consignados, sendo mantido o rigor metodológico em todas as etapas, com estimativas que respeitaram o intervalo de confiança, o que faz deste estudo passível de reprodução. Sugere-se que profissionais de outras instituições realizem tais mensurações, de modo que permitam a construção de indicadores, auxiliando enfermeiros na tomada de decisão.

Objective: To estimate the time intervals necessary to reprocess loaner items for total hip replacement in a sterile processing department of a private hospital in São Paulo (SP). Method: This is an exploratory, descriptive field study with a quantitative approach. The sample consisted of 41 processing cycles for loaner items. Intervals were recorded using a digital stopwatch, including the start and end times of each activity. Sample calculation was estimated with a 95% confidence interval. Results: Median total processing time was 10 hours, total effective time was 4.9 hours, and the interval between the end of reprocessing and the time of surgery was 4.7 hours in advance. One surgery was canceled due to delayed delivery of the item. Conclusions: This study measured the reprocessing times of loaner items, maintaining the methodological rigor at all stages, with estimates that respected the confidence interval, making this investigation reproduci-ble. We suggest that professionals from other facilities perform these measurements to allow the construction of indicators that can help nurses in decision-making.

Objetivo: Estimar los intervalos de tiempo involucrados en el reprocesamiento de materiales consignados temporalmente para reemplazo total de cadera en un Centro de Material y Esterilización de un hospital privado de São Paulo. Método: Estudio de campo exploratorio-descriptivo con enfoque cuantita-tivo. La muestra consistió en 41 procesamientos de materiales consignados. Los intervalos de tiempo se registraron con la ayuda de un cronómetro digital, hora de inicio y finalización de cada actividad. El cálculo del tamaño de la muestra se estimó con un intervalo de confianza del 95%. Resultados: El tiempo total de procesamiento tuvo una mediana de 10 horas; el tiempo efectivo total fue de 4,9 horas y el intervalo de tiempo entre el final del reprocesamiento y el momento de la cirugía fue de 4,7 horas antes. Se canceló una cirugía debido al retraso en la entrega del material. Conclusión: En esta investigación se midieron los tiem-pos de reprocesamiento de los materiales consignados, manteniendo el rigor metodológico en todas las etapas, con estimaciones que respetaron el intervalo de confianza, haciendo este estudio susceptible de reproducción. Se sugiere que profesionales de otras instituciones realicen dichas mediciones, de manera que per-mitan la construcción de indicadores, ayudando a las enfermeras en la toma de decisiones.

Concentración preoperatoria de fibrinógeno plasmático como predictor de sangrado en artroplastía total de cadera / Preoperative concentration of plasma fibrinogen as a predictor of bleeding in total hip arthroplasty

Resumen: Introducción: La artroplastía total de cadera tiene popularidad debido al éxito en el tratamiento de coxartrosis; son procedimientos asociados a la pérdida de sangre. Un sangrado importante provoca complicaciones como aumento en días de estancia intrahospitalaria, mayor costo de la enfermedad, exponiendo al paciente a complicaciones asociadas a transfusión sanguínea. El objetivo del estudio es investigar asociación entre concentración de fibrinógeno plasmático preoperatorio con sagrado transquirúrgico y determinar el nivel de corte de fibrinógeno para presentar mayor sangrado transquirúrgico. Material y métodos: Estudio retrospectivo, observacional, analítico, de Junio a Diciembre de 2020, incluyendo 227 pacientes con coxartrosis IV de la escala de Kellgren y Lawrence sometidos a artroplastía total primaria de cadera, derechohabientes, mayores de 18 años, en ausencia de enfermedades hepáticas o hematológicas y antecedente de sangrado quirúrgico importante. Resultados: El valor promedio de hemoglobina preoperatoria fue 14.6 ± 1.3 g/dl, posterior a cirugía (48 horas) 10.5 ± 1.4 g/dl; observando descenso de 4.1 ± 1.2 g/dl (p ≤ 0.0001). Valor promedio del hematocrito prequirúrgico 43% [41-45], posterior al procedimiento 32% [29-35]; se observó descenso de 11% [8-14] (p ≤ 0.0001); 98 pacientes presentaron sangrado transquirúrgico ≥ 300 ml; 129 tuvieron sangrado ≤ 300 ml; 61.2% de pacientes con sangrado mayor de 300 ml mostraron valores de fibrinógeno debajo del punto de corte (388 mg/dl). Conclusión: En pacientes postoperados los niveles preoperatorios de fibrinógeno ≤ 388 mg/dl y edad ≥ 58 años se asociaron al aumento en el riesgo del OR = 0.18 (IC 95% 0.10-0.32) de presentar sangrado transquirúrgico ≥ 300 ml, con descenso de la Hb de 4.1 ± 1.2 g/dl (p = 0.0001) y Hto de 11% [8-14] (p = 0.0001) entre el preoperatorio y el postoperatorio en 48 horas.

Abstract: Introduction: Total hip arthroplasty is popular for its success in treating coxarthrosis, its associated with substantial blood loss. Significant bleeding causes complications such as increase in hospitalization days, higher costs, exposing the patient to complications associated with blood transfusion. The aim of the study is to investigate the association between preoperative plasma fibrinogen concentration and trans-surgical bleeding and determine fibrinogen level cut-off to present greater trans-surgical bleeding. Material and methods: Retrospective, observational, analytical study, from June to December 2020, including 227 patients with Kellgren and Lawrence scale IV coxarthrosis undergoing primary total hip arthroplasty, beneficiaries, older than 18 years, without liver or hematological diseases, and history of significant surgical bleeding. Results: Mean preoperative hemoglobin value was 14.6 ± 1.3 g/dl, after surgery (48 hours) 10.5 ± 1.4 g/dl; decrease of 4.1 ± 1.2 g/dl (p ≤ 0.0001). Mean preoperative hematocrit value 43% [41-45], after the procedure; 32% [29-35]; decrease of 11% [8-14] (p ≤ 0.0001). 98 patients had intraoperative bleeding ≥ 300 ml, 129 had ≤ 300 ml; 61.2% of patients with bleeding greater than 300 ml had fibrinogen values below the cut-off point (388 mg/dl). Conclusion: In postoperative patients, preoperative fibrinogen levels ≤ 388 mg/dl and age ≥ 58 years were associated with an increased risk of OR = 0.18 (95% CI 0.10-0.32) of presenting trans-surgical bleeding ≥ 300 ml, with a decrease in Hb of 4.1 ± 1.2 g/dl (p = 0.0001) and Hto of 11% [8-14] (p = 0.0001) between the pre and postoperative period in 48 hours.

Visual impairment induced by prosthetic cobaltism.

The case of a 68-year-old patient with visual loss secondary to prosthetic cobaltism is reported. The degeneration of the metallic hip prosthesis can produce a systemic absorption of cobalt with cardiac, neurological, endocrine, auditory, and visual manifestations. The diagnostic suspicion is confirmed by serum cobalt measurements. Treatment with early surgery and chelating agents can lead to improvement of the visual, and the other disorders.

Concordancia interobservador en la clasificación de Paprosky en un hospital de un país de una economía emergente / Inter-observer agreement in the Paprosky classification in a hospital in a country of an emerging economy

Resumen: Introducción: La evaluación y manejo de la pérdida ósea acetabular en la artroplastía total de cadera es un desafío para los cirujanos ortopédicos, deseamos en este estudio determinar la concordancia interobservador en la clasificación de Paprosky para defectos acetabulares. Material y métodos: Estudio observacional, descriptivo, longitudinal, prospectivo. Se realizó utilizando las radiografías anteroposteriores de cadera de pacientes programados para artroplastía total de cadera primaria o de revisión con defecto óseo acetabular, sistema de rayos X local Sinapse, se valoraron 20 radiografías por observador tomadas de manera aleatoria (médicos adscritos al servicio de reemplazos articulares con experiencia mínima de cinco años) utilizando la clasificación de Paprosky de manera espontánea (sin clases previas) de defectos acetabulares, se evaluó la concordancia interobservador mediante el coeficiente de kappa de Cohen. Resultados: Se obtuvo una concordancia interobservador en promedio para la clasificación de Paprosky de defectos acetabulares utilizando el coeficiente de kappa de Cohen, el análisis de concordancia se hizo empleando el programa estadístico Statistical Package for the Social Sciences de 0.237. Conclusiones: Tanto la hipótesis nula (kappa mayor de 0.80 valor considerado óptimo) como la hipótesis alternativa (kappa de 0.41 a 0.80 valor igual a moderada a buena) no concordaron con nuestro estudio (kappa igual a 0.237) valor igual a leve, además se demostró que a mayor defecto acetabular menor es la concordancia interobservador en cirujanos en nuestra institución.

Abstract: Introduction: The evaluation and management of acetabular bone loss in total hip arthroplasty is a challenge for orthopedic surgeons, we wish in this study to determine the inter-observer concordance in the Paprosky classification for acetabular defects. Material and methods: Observational, descriptive, longitudinal, prospective study. It was performed using anteroposterior hip radiographs of patients scheduled for primary total hip arthroplasty or revision with acetabular bone defect, Sinapse local X-ray system, 20 X-rays were assessed per observer taken randomly (doctors assigned to the joint replacement service with minimum experience of five years) using the Paprosky classification spontaneously, (without previous classes) for acetabular defects, inter-observer concordance was assessed using Cohen's Kappa coefficient. Results: An interobserver agreement was obtained on average for the Paprosky classification of acetabular defects using the Cohen's Kappa coefficient, the concordance analysis was done using the statistical program statistical package for the social sciences of 0.237. Conclusions: Both the null hypothesis (Kappa greater than 0.80 value considered optimal) and the alternative hypothesis (Kappa from 0.41 to 0.80 value equal to moderate to good) did not agree with our study (Kappa equal to 0.237) value equal to mild, in addition , it was shown that the greater the acetabular defect, the lower the interobserver agreement in surgeons in our institution.

Fractura periprotésica acetabular intraoperatoria / Intraoperative acetabular periprotesic fracture

Resumen: Las fracturas intraoperatorias acetabulares (FIA) son una complicación rara con incidencia de 2 a 5%. Presentamos la revisión de una serie de 13 casos, que aborda diagnóstico, tratamiento y resultados. Material y métodos: entre 2006 y 2018 realizamos 4,800 artroplastías primarias de cadera (ATC). En nuestro hospital identificamos 13 casos con FIA con un seguimiento de 38.3 meses. Resultados: Dos casos fueron estables con manejo conservador; 11 casos inestables: en siete casos colocamos trabecular metal, en un caso aumentamos diámetro acetabular, en un caso recambio de cotilo, en un caso revisión con anillo tipo Ganz y un caso no aceptó tratamiento. El uso de trabecular metal es un implante que ayuda eficazmente y con buenos resultados en FIA. Conclusión: Estas fracturas son raras, conocer el implante a utilizar es imperativo, ya que si los implantes están sobredimensionados, con mayor rigidez o hemisféricos, los pacientes tienen mayor riesgo de sufrir esta complicación.

Abstract: Intraoperative acetabular fractures (IAF) is a rare complication with an incidence 2% - 5%. We present the review of a series of 13 cases, discussing diagnosis, treatment and results. Material and methods: Between 2006 and 2018, we performed 4800 primary hip arthroplasties (THA) In our hospital, we identified 13 cases with FIA with a follow-up of 38.3 months. Results: Two cases were stable with conservative management; 11 unstable cases: seven cases we placed trabecular metal, one case we increased acetabular diameter, one case acetabular replacement, one case revision with Ganz type ring and one case do not accept treatment. The use of trabecular metal is an implant that helps effectively and with good results in FIA. Conclusion: These fractures are rare, knowing the implant to use is mandatory because if the implants are oversized, with greater rigidity or hemispheric, patients have increased risk of suffering from this complication.

Descripción del posicionamiento de una copa monobloque no cementada en el posoperatorio inmediato / Description of uncemented monobloc cup positioning in the immediate postoperative period

Introducción El posicionamiento adecuado de la copa acetabular en el reemplazo total de cadera (RTC) puede mejorar la función, reducir el desgaste, el pinzamiento y la luxación. La posición de la copa se describe como la relación espacial entre el centro de rotación de la cadera y la pelvis. El objetivo de este estudio es describir el posicionamiento de una copa monobloque no cementada en el posoperatorio inmediato de los pacientes a quienes se les realizo un RTC primario. Materiales y Métodos Estudio observacional descriptivo, los pacientes fueron operados por 4 cirujanos especialistas en cirugía de reemplazo articular de cadera en 8 clínicas, los procedimientos se realizaron entre octubre de 2015 a agosto de 2018, las medidas radiológicas fueron la inclinación, anteversión, lateralización, porcentaje de descubrimiento y espacio detrás de la copa acetabular. Resultados Los mayores porcentajes son para las copas acetabulares con inclinación de 36 a 48 grados, anteversión de 5 a 15 grados, lateralización de -2 a +2mm, porcentaje de descubrimiento del 0% y espacio detrás de la copa de 0 a 3mm. Discusión Diferentes autores han identificado zonas seguras de implantación las cuales concuerdan con los resultados de nuestro estudio. El posicionamiento adecuado de la copa acetabular monobloque no cementada se pudo lograr con una correcta indicación del implante, un abordaje quirúrgico que permitió una ubicación tridimensional idónea y un acetábulo sin alteraciones anatómicas a nivel periférico.

Background Appropriate positioning of the acetabular cup in total hip arthroplasty (THA) can improve hip function, reduce wear, impingement and dislocation. The position of the cup is described as the spatial relationship between the centre of rotation of the hip and the pelvis. The aim of this study is to describe the positioning of the uncemented monoblock cup in the immediate postoperative period in patients who underwent a primary THA. Methods Descriptive observational study. The patients were operated by 4 joints arthroplasty surgeons in 8 different hospitals, from October 2015 to August 2018. The radiological measurements were taken from the AP Pelvis Xrays of the immediate postoperative. The inclination, anteversion, lateralization, percentage of cup uncovered and the space behind the acetabular cup. Results 82.05% of the cups were in the range of inclination from 36 to 48 degrees; 85.71% had an anteversion between 5 to 15 degrees, 76.56% presented a lateralization of -2 to +2mm, 94.51% of the patients didnt have a uncover cup, and 92.67% of the cups had a space behind the cup from 0 to 3mm. Discussion In our study the highest percentage of cups were implanted with parameters agree to the safety areas reported by various authors. Adequate positioning of the uncemented monoblock acetabular cup can be achieved with a proper indication, a surgical approach that allows an ideal three-dimensional location and an acetabulum with a good peripheral rim that provides the required press-fit.

Análisis Biomecánico de una Prótesis de Cadera mediante Elementos Finitos / Biomechanical Analysis of a Hip Prosthesis Using a Finite Element

Resumen En el presente trabajo se plantea un análisis biomecánico de una prótesis de cadera bajo condiciones de cargas estáticas asociadas a actividades cotidianas, en el cual se comparan tres materiales metálicos para la fabricación de una prótesis personalizada a partir de imágenes médicas. Se utilizaron plataformas en la nube de diseño asistido por computadora y de análisis por elementos finitos. Se diseñaron dos modelos de la prótesis a analizar, uno hueco y otro sólido mediante curvas spline paramétricas. Para el análisis biomecánico se requirió un tamaño de malla de 2,537,684 de elementos tetraédricos y 471,335 nodos para estudiar siete casos de posturas para una persona de 75 kg de peso, mismos que se analizaron tomando como materiales base acero inoxidable 316L, aleación Ti-6AL-4V y L-605. Se observó que con actividades tales como trotar, subir y bajar escaleras los materiales 316L y L-605, presentan el riesgo de deformación plástica e inclusive fractura. Los resultados mostraron que el material más idóneo para la fabricación de este tipo de prótesis es el Ti-6Al-4V, además de que este nos permite realizar modelos tanto sólidos como huecos, suponiendo este último, un ahorro de material y proporcionando mayor ligereza en la prótesis.

Abstract This paper shows a biomechanical analysis of a hip prosthesis under conditions of static loads associated with daily activities. For which it compared three metallic materials for the manufacture of a customized prosthesis from medical images, it was used cloud platforms with computer-aided design and finite element analysis. Two models of prosthesis one hollow and the other one solid using parametric spline curves were designed and analyzed. The biomechanical analysis required a mesh size consisting of 2,537,684 tetrahedral elements and 471,335 nodes to study seven cases of postures for a person weighing 75 kg. These cases were analyzed based on 316L stainless steel, Ti-6AL-4V alloy, and another L-605 alloy. It was observed that with activities such as jogging, climbing and descending stairs, materials 316L, and L-605 present the risk of plastic deformation and even fracture. The results show that the most suitable material for the manufacture of this type of prosthesis is the Ti-6Al-4V, which allows us to make both solid and hollow models. Assuming this last material is saved and improves the prosthesis lightness.

Aplicación profiláctica de sulfato de calcio medicado en prótesis total de cadera no cementada / Prophylactic application of medicated calcium sulphate in uncemented total hip prosthesis

Resumen: El incremento en la cirugía de artroplastía total de cadera es motivado por muchos factores, como el aumento en la expectativa de vida, mejoría continua en la técnica quirúrgica e innovaciones en el diseño y los materiales de los implantes que, sumados, han convertido a este procedimiento en una solución efectiva a la degeneración articular, con excelentes resultados. Sin embargo, a pesar de los avances tecnológicos, la infección periprotésica se ha mantenido como una de las complicaciones más devastadoras. Este estudio evalúa la aplicación profiláctica de perlas de sulfato de calcio medicadas en el canal femoral y superficie acetabular para prevenir infecciones periprotésicas en pacientes que fueron sometidos a una artroplastía total de cadera primaria no cementada contra un grupo control mediante la medición de reactantes de fase aguda y cultivo de líquido sinovial. Se sometieron al estudio 146 individuos: 67 a quienes se les aplicaron perlas de sulfato de calcio medicado y 79 a quienes se les aplicó antibiótico profiláctico intravenoso de Septiembre de 2013 a Agosto de 2016. Como método diagnóstico de infección periprotésica temprana se evaluaron la proteína C reactiva asociada a velocidad de sedimentación globular aumentada, una fístula que comunicara con la prótesis, cultivo positivo de dos o más sitios periprotésicos de líquido sinovial o tejido. Los resultados clínicos demostraron que hubo una disminución en los valores de los reactantes de fase aguda en los sujetos a quienes se les aplicaron las perlas de sulfato de calcio medicado. Se encontró que 14 personas presentaron infección en el grupo con profilaxis parenteral, comparado con tres del grupo con profilaxis local con perlas de sulfato de calcio medicado; ambos grupos con ceftriaxona. Se consideró que el uso profiláctico de perlas de sulfato de calcio dentro de canal medular y la superficie acetabular es una buena opción para prevenir infecciones periprotésicas en quienes han sido sometidos a una artroplastía total de cadera primaria no cementada; sin embargo el estudio amerita seguimiento con más pacientes para tener significancia estadística.

Abstract: The increase in total hip arthroplasty occurs by many factors, such as increasing life expectancy, improving surgical technique as well as innovating the design and implant material. However, despite technological advances, peri-prosthetic infection has remained one of the most devastating complications. This study evaluates the prophylactic application of calcium sulfate pearls medicated in the femoral canal and acetabular surface to prevent peri-prosthetic infections in patients who underwent total uncemented primary hip arthroplasty against a control group by measuring acute phase reactants. 146 patients, 67 were applied calcium sulfate pearls medicated and 79 prophylactic antibiotic intravenous in the period from 2013 to 2016. To perform the diagnosis of peri-prosthetic infection was assessed PCR associated with VSG, communication between fistula and prostheses and positive culture in 2 or more different sites. There was a decrease in the values of acute-phase reactants in patients who were given calcium sulfate pearls. 14 patients presented infection in the control group and 3 in the study group. The prophylactic use of calcium sulphate pearls within the medullary canal and acetabular surface is an option for the prophylaxis of peri-prosthetic infections, however the study deserves follow-up with more patients.

Interimplant femoral fractures: risk factors, treatment and evolution. / Fracturas interimplante de fémur: factores de riesgo, tratamiento y evolución.

OBJECTIVE: The aim of this study is to determine the risk factors involved in the development of these fractures and analyze the treatments used as well as their influence on the clinical and functional prognosis of patients. MATERIALS AND METHODS: We made an observational, retrospective case-control study, with a sample of 38 patients (40 femoral bones) operated in our hospital, who had two femoral ipsilateral implants, proximal and distal. We found 10 cases of interimplant fracture and 28 patients who had not suffered a fracture (2 of them had bilateral implants). We analyzed the influence of different variables, such as age, gender, comorbidities, radiological variables, type of treatments employed, clinical evolution, etc. RESULTS: the female sex was predominant in both groups, 80.7 was the average age. Osteoporosis was statistically significant (P=.007) for the development of these fractures. We did not find statistical significance in the radiological variables. Surgical treatment was the most frequent, and the plate of osteosynthesis the most employed option. We found a death rate of 40% at 4 years. Although all fractures healed, the survivors' ambulation ability was reduced. CONCLUSIONS: interimplant fractures are predominant in elderly women. Osteoporosis is a statistically significant risk factor. Despite optimal treatment and fracture healing, functional outcomes were decreased. Specific classification systems and therapeutic algorithms are necessary to improve the management and prognosis of these patients.