[Translated article] Comparative clinical and biomechanical study of different types of osteosynthesis in the treatment of distal femur fractures.

INTRODUCTION AND OBJECTIVES: Distal femoral fractures represent a problem due to their high number of complications. The aim was to compare the results, complications and stability achieved with retrograde intramedullary nailing and the angular stable plate in the treatment of distal femoral diaphyseal fractures. MATERIAL AND METHOD: A clinical and experimental biomechanical study was carried out using finite elements. The results of the simulations allowed us to obtain the main results related to the stability of osteosynthesis. For clinical follow-up data, frequencies were used for qualitative variables, and Fisher's exact test and χ2 test were used to evaluate the significance of the different factors, with the condition of P<.05. RESULTS: In the biomechanical study, the retrograde intramedullar nails demonstrated superiority, obtaining lower values in terms of global displacement, maximum tension, torsion resistance, and bending resistance. In the clinical study, the rate of consolidation of the plates was lower than nails (77% vs. 96%, P=.02). The factor that most influenced the healing of fractures treated with plate were the central cortical thickness (P=.019). The factor that most influenced the healing of nail-treated fractures was the difference between the diameter of the medullary canal and the nail. CONCLUSIONS: Our biomechanical study shows that both osteosynthesis provide sufficient stability, but biomechanically behaves differently. Nails provide greater overall stability being preferable the use of long nails adjusted to the diameter of the canal. Plates form less rigid osteosynthesis, with little resistance to bending.

Comparative clinical and biomechanical study of different types of osteosynthesis in the treatment of distal femur fractures. / Estudio comparativo clínico y biomecánico de distintos tipos de osteosíntesis en el tratamiento de fracturas distales de fémur.

INTRODUCTION AND OBJECTIVES: Distal femoral fractures represent a problem due to their high number of complications. The aim was to compare the results, complications and stability achieved with retrograde intramedullary nailing and the angular stable plate in the treatment of distal femoral diaphyseal fractures. MATERIAL AND METHOD: A clinical and experimental biomechanical study was carried out using finite elements. The results of the simulations allowed us to obtain the main results related to the stability of osteosynthesis. For clinical follow-up data, frequencies were used for qualitative variables, and Fisher's exact test and χ2 test were used to evaluate the significance of the different factors, with the condition of P<.05. RESULTS: In the biomechanical study, the retrograde intramedullar nails demonstrated superiority, obtaining lower values in terms of global displacement, maximum tension, torsion resistance, and bending resistance. In the clinical study, the rate of consolidation of the plates was lower than nails (77% vs. 96%, P=.02). The factor that most influenced the healing of fractures treated with plate were the central cortical thickness (P=.019). The factor that most influenced the healing of nail-treated fractures was the difference between the diameter of the medullary canal and the nail. CONCLUSIONS: Our biomechanical study shows that both osteosynthesis provide sufficient stability, but biomechanically behaves differently. Nails provide greater overall stability being preferable the use of long nails adjusted to the diameter of the canal. Plates form less rigid osteosynthesis, with little resistance to bending.

Influence of plate size and screw distribution on the biomechanical behaviour of osteosynthesis by means of lateral plates in femoral fractures.

Distal femoral fractures are fractures associated with high rates of morbidity and mortality, affecting to three different groups of individuals: younger people suffering high-energy trauma, elderly people with fragile bones and people with periprosthetic fractures around previous total knee arthroplasty. They have been classically treated with conventional plates and intramedullary nails and more recently with locked plates that have increased their indications to more types of fractures. The main objective of the present work is the biomechanical study, by means of finite element simulation, of the stability achieved in the osteosynthesis of femoral fractures in zones 4 and 5 of Wiss, by using locked plates with different plate lengths and different screw configurations, and analysing the effect of screw proximity to the fracture site. A three dimensional (3D) finite element model of the femur from 55-year-old male donor was developed, and then a stability analysis was performed for the fixation provided by Osteosynthesis System LOQTEC® Lateral Distal Femur Plate in two different fracture zones corresponding to the zones 4 and 5 according to the Wiss fracture classification. The study was focused on the immediately post-operative stage, without any biological healing process. The obtained results show that more stable osteosyntheses were obtained by using shorter plates. In the cases of longer plates, it results more convenient disposing screws in a way that the upper ones are closer to fracture site. The obtained results can support surgeons to understand the biomechanics of fracture stability, and then to guide them towards the more appropriate osteosynthesis depending on the fracture type and location.

Fractura de cadera en pacientes centenarios, ¿qué podemos esperar? / Hip fracture in centenarians, what can we expect?

Introducción: La mejoría de la esperanza de vida está incrementando la incidencia de fractura de cadera en centenarios. Nuestro objetivo es comparar las características basales de una serie de centenarios con fractura de cadera frente a controles de menor edad, analizando si existen diferencias en cuanto a complicaciones, mortalidad intrahospitalaria y supervivencia a corto-medio plazo. Material y métodos: Estudio retrospectivo, tipo caso control, sobre 24 centenarios y 48 controles octogenarios con fractura de cadera. Se analizó la presencia de comorbilidades y el índice de Charlson, la demora quirúrgica, las complicaciones, la estancia hospitalaria y la mortalidad durante el ingreso. Al alta se valoró la mortalidad precoz, la supervivencia después del año y el retorno a la funcionalidad previa. Resultados: No se encontraron diferencias significativas en parámetros basales ni en comorbilidades (p>0,05), siendo el paciente tipo una mujer con fractura extracapsular. La estancia hospitalaria fue mayor en el grupo control (p=0,038) y la complicación más frecuente la anemia, que precisó transfusión sanguínea (23/24 en los centenarios, p<0,0001). La mortalidad intrahospitalaria y acumulada al año en los centenarios fue del 33 y el 67%, respectivamente, frente al 10 y 25% en octogenarios (p=0,017, OR=4,3 [1,224-15,101] y p=0,110]. Solo 2 pacientes centenarios consiguieron volver a caminar tras la intervención, frente a un 53,84% que volvió a la situación funcional previa en los controles (p=0,003). Conclusiones: Frente a un grupo control de pacientes de menor edad, la mortalidad intrahospitalaria y en el primer año tras una fractura de cadera es significativamente mayor en los centenarios y muy pocos recuperan la actividad previa a la fractura.(AU)

Introduction: Hip fractures in centenarians are rising due to the increase in life expectancy. The objective of this study is to compare the characteristics of centenarians’ hip fracture with a younger control group, and to analyze whether there are differences in terms of in-hospital mortality, complications, and short-medium-term survival between them. Material and methods: Retrospective case-control study, with a series of 24 centenarians and 48 octogenarians with a hip fracture. Comorbidities and Charlson index, surgical delay, complications and mortality during admission, and hospital stay were analyzed. At discharge, early mortality, survival after one year, and return to previous functionality were assessed. Results: No significant differences were found in baseline parameters or comorbidities (P>.05), and the type of was a woman with an extracapsular fracture. Hospital stay was longer in the control group (P=.038), and the most frequent complication was anemia requiring transfusion (23/24 in centenarians, P<.0001). In-hospital mortality and accumulated at one year in the centenarians was 33 and 67%, respectively, compared to 10 and 25% in the octogenarians (P=.017, OR=4.3 [1,224-15,101] and P=.110). Only 2 centenarian patients were able to walk again after the intervention, while in the control group 53.84% returned to the previous functional situation (P=.003). Conclusions: Compared to a control group of younger patients, in-hospital mortality and in the first year after a hip fracture is significantly higher in centenarians, and very few recover activity prior to the fracture.(AU)

Hip fracture in centenarians, what can we expect? / Fractura de cadera en pacientes centenarios. ¿Qué podemos esperar?

Introduction: Hip fractures in centenarians are rising due to the increase in life expectancy. The objective of this study is to compare the characteristics of centenarians’ hip fracture with a younger control group, and to analyze whether there are differences in terms of in-hospital mortality, complications, and short-medium-term survival between them. Material and methods: Retrospective case-control study, with a series of 24 centenarians and 48 octogenarians with a hip fracture. Comorbidities and Charlson index, surgical delay, complications and mortality during admission, and hospital stay were analyzed. At discharge, early mortality, survival after one year, and return to previous functionality were assessed. Results: No significant differences were found in baseline parameters or comorbidities (P>.05), and the type of was a woman with an extracapsular fracture. Hospital stay was longer in the control group (P=.038), and the most frequent complication was anemia requiring transfusion (23/24 in centenarians, P<.0001). In-hospital mortality and accumulated at one year in the centenarians was 33 and 67%, respectively, compared to 10 and 25% in the octogenarians (P=.017, OR=4.3 [1,224-15,101] and P=.110). Only 2 centenarian patients were able to walk again after the intervention, while in the control group 53.84% returned to the previous functional situation (P=.003). Conclusions: Compared to a control group of younger patients, in-hospital mortality and in the first year after a hip fracture is significantly higher in centenarians, and very few recover activity prior to the fracture.(AU)

Introducción: La mejoría de la esperanza de vida está incrementando la incidencia de fractura de cadera en centenarios. Nuestro objetivo es comparar las características basales de una serie de centenarios con fractura de cadera frente a controles de menor edad, analizando si existen diferencias en cuanto a complicaciones, mortalidad intrahospitalaria y supervivencia a corto-medio plazo. Material y métodos: Estudio retrospectivo, tipo caso control, sobre 24 centenarios y 48 controles octogenarios con fractura de cadera. Se analizó la presencia de comorbilidades y el índice de Charlson, la demora quirúrgica, las complicaciones, la estancia hospitalaria y la mortalidad durante el ingreso. Al alta se valoró la mortalidad precoz, la supervivencia después del año y el retorno a la funcionalidad previa. Resultados: No se encontraron diferencias significativas en parámetros basales ni en comorbilidades (p>0,05), siendo el paciente tipo una mujer con fractura extracapsular. La estancia hospitalaria fue mayor en el grupo control (p=0,038) y la complicación más frecuente la anemia, que precisó transfusión sanguínea (23/24 en los centenarios, p<0,0001). La mortalidad intrahospitalaria y acumulada al año en los centenarios fue del 33 y el 67%, respectivamente, frente al 10 y 25% en octogenarios (p=0,017, OR=4,3 [1,224-15,101] y p=0,110]. Solo 2 pacientes centenarios consiguieron volver a caminar tras la intervención, frente a un 53,84% que volvió a la situación funcional previa en los controles (p=0,003). Conclusiones: Frente a un grupo control de pacientes de menor edad, la mortalidad intrahospitalaria y en el primer año tras una fractura de cadera es significativamente mayor en los centenarios y muy pocos recuperan la actividad previa a la fractura.(AU)

Hip fracture in centenarians, what can we expect? / Fractura de cadera en pacientes centenarios, ¿qué podemos esperar?

INTRODUCTION: Hip fractures in centenarians are rising due to the increase in life expectancy. The objective of this study is to compare the characteristics of centenarians' hip fracture with a younger control group, and to analyze whether there are differences in terms of in-hospital mortality, complications, and short-medium-term survival between them. MATERIAL AND METHODS: Retrospective case-control study, with a series of 24 centenarians and 48 octogenarians with a hip fracture. Comorbidities and Charlson index, surgical delay, complications and mortality during admission, and hospital stay were analyzed. At discharge, early mortality, survival after one year, and return to previous functionality were assessed. RESULTS: No significant differences were found in baseline parameters or comorbidities (P>.05), and the type of was a woman with an extracapsular fracture. Hospital stay was longer in the control group (P=.038), and the most frequent complication was anemia requiring transfusion (23/24 in centenarians, P<.0001). In-hospital mortality and accumulated at one year in the centenarians was 33 and 67%, respectively, compared to 10 and 25% in the octogenarians (P=.017, OR=4.3 [1,224-15,101] and P=.110). Only 2 centenarian patients were able to walk again after the intervention, while in the control group 53.84% returned to the previous functional situation (P=.003). CONCLUSIONS: Compared to a control group of younger patients, in-hospital mortality and in the first year after a hip fracture is significantly higher in centenarians, and very few recover activity prior to the fracture.

Biomechanical behavior of retrograde intramedullary nails in distal femoral fractures.

Fractures of the distal femur affect three different groups of individuals: younger people suffering high-energy trauma, elderly people with fragile bones and people with periprosthetic fractures around previous total knee arthroplasty. Main indications of intramedullary nailing are for supracondylar fractures type A or type C of the AO classification. The main objective of the present work is to analyze, by means of FE simulation, the influence of retrograde nail length, considering different blocking configurations and fracture gaps, on the biomechanical behavior of supracondylar fractures of A type. A three dimensional (3D) finite element model of the femur from 55-year-old male donor was developed, and then a stability analysis was performed for the fixation provided by the retrograde nail at a distal fracture with different fracture gaps: 0.5 mm, 3 mm y 20 mm, respectively. Besides, for each gap, three nail lengths were studied with a general extent (320 mm, 280 mm and 240 mm), considering two transversal screws (M/L) at the distal part and different screw combinations above the fracture. The study was focused on the immediately post-operative stage, without any biological healing process. In view of the obtained results, it has been demonstrated new possibilities of blocking configuration in addition to the usual ones, which allows establishing recommendations for nail design and clinical practice, avoiding excessive stress concentrations both in screws, with the problem of rupture and loss of blocking, and in the contact of nail tip with cortical bone, with the problem of a new stress fracture.

Salvage of cephalomedullary nail cutout with the variable angle proximal femoral plate.

INTRODUCTION: Excellent results have been published in the treatment of the trochanteric fractures in the elderly with cephalomedullary nails or compression hip screws but not free of complications. The perforation of the lag screw through the superior cortex of femoral neck or head followed by rotation and varus collapse of the head-neck fragment, also known as cut-out, is one of them. Probably total hip arthroplasty is the most common solution, but there is no systematic technique for treatment. The objective of this study is to evaluate the results obtained in the treatment of this complication using a variable angle femoral plate. MATERIAL AND METHODS: This retrospective study concerns patients over 65 years with peritrochanteric fractures treated with cephalomedullary nail with cut-out failure solved by re-osteosyntesis with variable angle femoral plate between 1st January 2000 and 31 st December 2017. The series includes 29 patients, 26 women and 3 men with average age 87,3. Patients were followed up clinically and radiologically at regular intervals until fracture consolidation at least 9 months. RESULTS: No patients died at the first 9 months after surgery. Fracture mean consolidation has occurred in all patients in 14th weeks (6-20). Operative time was 93,2 minutes (62-129) including removal of nail. No intraoperative complications were observed. Five patients experienced medical complications and two had a superficial wound infection. The mean tip-apex distance (TAD) was 5mm (2-7mm). The neck-shaft angle was 127 degrees. The mean valgization achieved was 32 degrees (15-40). Only one patient needed a second revision surgery due to aseptic hip joint subluxation after 8 weeks of the surgery solved with total hip arthroplasty. CONCLUSIONS: The use of variable angle femoral plate in the cut-out treatment is an attractive option which allows the valgization of the fracture to virtually physiological limits and the placement of the cephalic screw in the most sutiable position with good outcomes and few complications.

Is the mortality higher in patients who have suffered a hip fracture? / ¿Es mayor la mortalidad en los pacientes que han sufrido una fractura de cadera?

BACKGROUND AND OBJECTIVE: The aim of this study is to value whether patients who have suffered a hip fracture have a higher mortality than expected. MATERIAL AND METHODS: A prospective, observational study was carried out where patients with hip fracture were collected as a sample over a year. The study included 284 patients and a minimum follow-up was 2 years. The mean age of these patients was 84.26 years, with 21.48% (61/284) males and 78.5% (223/284) females. Survival and previous diseases that affect mortality, as risk factors, were collected and analyzed using the Kaplan-Meier method and the Cox regression model. Actual mortality was compared with that expected according to the Charlson Comorbidity Index, adjusted for age. RESULTS: Previous pathology was the main mortality factor, with heart disease being the most significant (OR 1.817, CI95%: 1.048; 3.149). The real mortality at one year of the sample was 22.5%, while the estimated annual mortality according to the Charlson Comorbidity Index was 29.68% (CI95%:44,36-15). CONCLUSIONS: Hip fracture does not cause an increase in mortality according to the Charlson Comorbidity Index estimate.

Factores de riesgo en fractura periprotésica femoral tras artroplastia sustitutiva primaria de rodilla / Risk factors of periprosthetic femoral fracture after total knee arthroplasty

INTRODUCCIÓN Y OBJETIVOS: Las fracturas periprotésicas tras artroplastia primaria de rodilla cobran gran importancia en nuestro medio debido tanto al aumento de su incidencia, como al reto que suponen para el cirujano. Múltiples factores se han asociado a su producción. El objetivo del estudio fue identificar los factores de riesgo que podían influir en la aparición de estas fracturas, cuáles de todos ellos son modificables y generar un modelo de predicción de probabilidad de las mismas en función de dichos factores. MATERIAL Y MÉTODO: Estudio analítico, observacional, retrospectivo, no pareado, de 38 casos de fracturas periprotésicas femorales de rodilla y 80 controles con prótesis de rodilla. En total, fueron incluidos en el estudio 118 pacientes, 83 mujeres y 35 hombres con una edad media de 72,49 años. Se recogieron datos sociodemográficos, antecedentes médicos y consumo de fármacos, así como los relativos a la cirugía. Se realizó un análisis uni- y bivariante de los factores determinantes de fractura, usando un modelo de regresión logística para evitar el sesgo de confusión. RESULTADOS: De todos los factores estudiados según el modelo de regresión logística, se obtuvo que el sexo femenino (OR = 7,6), la demencia (OR = 5), la alteración motora/párkinson (OR = 19,3) y el sobrecorte femoral anterior (OR = 8,6) eran factores asociados al incremento de riesgo de este tipo de fracturas. CONCLUSIONES: Este trabajo permite concluir que hay factores de riesgo, como son el sexo femenino, la demencia y el párkinson, que aumentan la probabilidad de fractura periprotésica, que son inherentes al paciente y no son modificables. Sin embargo, existe algún otro totalmente modificable que puede evitarse siendo exigente y exhaustivo en la técnica quirúrgica, como es el sobrecorte femoral anterior

INTRODUCTION AND OBJECTIVES: Periprosthetic fractures after primary knee arthroplasty has great importance in our environment due to the increase in their incidence and to the challenge they pose to the surgeon. Multiple factors have been associated with its production. The objective of the study was to identify the risk factors that could influence the appearance of these fractures, which of them are all modifiable and generate a probability prediction model based on these factors. MATERIAL AND METHODS: Analytical, observational, retrospective, unpaired study of 38 cases of periprosthetic femoral knee fractures and 80 controls with knee prostheses. In total, 118 patients, 83 women and 35 men with a mean age of 72.49 years were included in the study. Sociodemographic data, medical history and drug consumption were collected, as well as those related to surgery. A univariate and bivariate analysis of the fracture determining factors was performed, using a logistic regression model to avoid confusion bias. RESULTS: Of all the factors studied according to the logistic regression model, it was obtained that female sex (OR = 7.6), dementia (OR = 5), motor/parkinson's alteration (OR = 19.3) and femoral overcut Previous (OR = 8.6) were factors associated with the increased risk of this type of fractures. CONCLUSIONS: This work allows us to conclude that there are risk factors such as female sex, dementia and parkinson's that increase the probability of periprosthetic fracture that are inherent to the patient and are not modifiable. However, there is any other totally modifiable that can be avoided by being demanding and thorough in the surgical technique, such as the anterior femoral overcut

Risk factors of periprosthetic femoral fracture after total knee arthroplasty. / Factores de riesgo en fractura periprotésica femoral tras artroplastia sustitutiva primaria de rodilla.

INTRODUCTION AND OBJECTIVES: Periprosthetic fractures after primary knee arthroplasty has great importance in our environment due to the increase in their incidence and to the challenge they pose to the surgeon. Multiple factors have been associated with its production. The objective of the study was to identify the risk factors that could influence the appearance of these fractures, which of them are all modifiable and generate a probability prediction model based on these factors. MATERIAL AND METHODS: Analytical, observational, retrospective, unpaired study of 38 cases of periprosthetic femoral knee fractures and 80 controls with knee prostheses. In total, 118 patients, 83 women and 35 men with a mean age of 72.49 years were included in the study. Sociodemographic data, medical history and drug consumption were collected, as well as those related to surgery. A univariate and bivariate analysis of the fracture determining factors was performed, using a logistic regression model to avoid confusion bias. RESULTS: Of all the factors studied according to the logistic regression model, it was obtained that female sex (OR = 7.6), dementia (OR = 5), motor/parkinson's alteration (OR = 19.3) and femoral overcut Previous (OR = 8.6) were factors associated with the increased risk of this type of fractures. CONCLUSIONS: This work allows us to conclude that there are risk factors such as female sex, dementia and parkinson's that increase the probability of periprosthetic fracture that are inherent to the patient and are not modifiable. However, there is any other totally modifiable that can be avoided by being demanding and thorough in the surgical technique, such as the anterior femoral overcut.