Development of a Machine-Learning Model for Anterior Knee Pain After Total Knee Arthroplasty With Patellar Preservation Using Radiological Variables.

BACKGROUND: Anterior knee pain (AKP) following total knee arthroplasty (TKA) with patellar preservation is a common complication that significantly affects patients' quality of life. This study aimed to develop a machine-learning model to predict the likelihood of developing AKP after TKA using radiological variables. METHODS: A cohort of 131 anterior stabilized TKA cases (105 patients) without patellar resurfacing was included. Patients underwent a follow-up evaluation with a minimum 1-year follow-up. The primary outcome was AKP, and radiological measurements were used as predictor variables. There were 2 observers who made the radiological measurement, which included lower limb dysmetria, joint space, and coronal, sagittal, and axial alignment. Machine-learning models were applied to predict AKP. The best-performing model was selected based on accuracy, precision, sensitivity, specificity, and Kappa statistics. Python 3.11 with Pandas and PyCaret libraries were used for analysis. RESULTS: A total of 35 TKA had AKP (26.7%). Patient-reported outcomes were significantly better in the patients who did not have AKP. The Gradient Boosting Classifier performed best for both observers, achieving an area under the curve of 0.9261 and 0.9164, respectively. The mechanical tibial slope was the most important variable for predicting AKP. The Shapley test indicated that high/low mechanical tibial slope, a shorter operated leg, a valgus coronal alignment, and excessive patellar tilt increased AKP risk. CONCLUSIONS: The results suggest that global alignment, including sagittal, coronal, and axial alignment, is relevant in predicting AKP after TKA. These findings provide valuable insights for optimizing TKA outcomes and reducing the incidence of AKP.

Similar Patient Satisfaction and Quality of Life Improvement Achieved with TKA and THA According to the Goodman Scale: A Comparative Study.

Background: Total knee arthroplasty (TKA) and total hip arthroplasty (THA) are effective treatments for severe knee and hip osteoarthritis. Historically, TKA has been associated with lower satisfaction than THA, but recent advances in knee surgery have led to lower dissatisfaction rates. This study aimed to compare the satisfaction and self-reported improvement in the quality of life of two cohorts of patients who underwent TKA and THA, respectively. Methods: This observational study compared two previously published cohorts of patients who underwent THA and TKA in a single university center. The Goodman scale was used to assess satisfaction and self-perception of improved quality of life after TKA and THA at a minimum one-year follow-up. Propensity score matching was used to balance age, gender, and follow-up between groups. Significance was set at 0.05. Results: The study included a total of 105 THAs and 131 TKAs. Both groups had high levels of satisfaction with pain relief, ability to do house/yard work, and overall satisfaction, with above 90% satisfaction rates. Regarding improvement in quality of life, both groups had 86% of patients reporting improvement as "much better." After propensity score matching, no significant difference was found between THA and TKA for any of the comparisons made using the Goodman scale. Conclusions: The study showed that both TKA and THA resulted in high levels of satisfaction and improvement in quality of life. There was no significant difference in satisfaction rates between TKA and THA, contrary to the historical trend of lower satisfaction rates for TKA.

Anterior knee pain and sit-up tests predicts patients' satisfaction and improvement in quality of life after anterior stabilized total knee replacement without patellar resurfacing.

PURPOSE: The purpose of this study was to assess patient satisfaction and identify risk factors for dissatisfaction after anterior stabilised conventional total knee arthroplasty (TKA) without patellar resurfacing, using the Goodman score. METHODS: We conducted a cross-sectional study using data from our institutional database from 1 January 2018 to 1 March 2021. Patients who underwent TKA with the Vanguard® Cruciate Retaining Anterior Stabilized Knee System (Zimmer Biomet, Warsaw, Indiana, USA) without patellar replacement were included. Patients with other bearing surfaces (posterior stabilised or medial congruent) or diagnosed with infection or instability were excluded. Patients' reported outcomes, body mass index (BMI), passive range of motion, the timed up-and-go test, sit-up test, and algometry were assessed. Patients were also asked if they had anterior knee pain. Satisfaction was assessed using the Goodman scale, and logistic multivariate regression was used to identify variables associated with dissatisfaction and perceived improvement in quality of life. RESULTS: A total of 131 TKA patients were included in the study. The median satisfaction score was 100 (interquartile range [IQR], 87.5 to 100), with the 75-point threshold at the 90th percentile according to Section A of Goodman. Section B of Goodman showed that 113 TKA patients (86.26%) reported "great improvement" or "more than I ever dreamed." Multivariate logistic regression revealed that anterior knee pain (OR 5.16, 95% CI 1.24 to 21.39), the sit-up test (OR 0.63, 95% CI 0.49 to 0.81), and BMI (OR 0.84, 95% CI 0.70 to 0.99) were significantly associated with patient dissatisfaction and a worse perceived improvement in quality of life. The receiver operating characteristics curve for the models had areas under the curve of 0.83 (95% CI 0.69 to 0.97) and 0.82 (95% CI 0.70 to 0.94), respectively. CONCLUSION: Anterior stabilised TKA without patellar resurfacing can achieve 90% satisfaction and 86% improvement in quality of life. To improve these results, it is essential to prevent and treat anterior knee pain and enhance quadriceps strength. LEVEL OF EVIDENCE: Level III (retrospective cohort study).

Estimación de la eficiencia del uso de pabellones electivos en el sistema de salud público chileno entre 2018 y 2021. / Efficiency estimation on the use of elective surgical theaters in the Chilean public health system from 2018 to 2021.

Objective: The efficient use of wards intended for elective surgeries is essential to resolve cases on the surgical waiting list. This study aims to estimate the efficiency of ward use in the Chilean public health system between 2018 and 2021. Methods: The design was an ecological study. Section A.21 of the database constructed by the monthly statistical summaries that each public health network facility reported to the Ministry of Health between 2018 and 2021 was analyzed. Data from subsections A, E and F were extracted: ward staffing, total elective surgeries by specialty, number and causes of suspension of elective surgeries. Then, the surgical performance during working hours and the percentage of hourly occupancy for a working day was estimated. Additionally, an analysis was made by region with data from 2021. Results: The percentage of elective wards in use ranged from 81.1% to 94.1%, while those enabled for those staffing ranged from 70.5% to 90.4% during 2018 and 2021. The total number of surgeries was highest in 2019 (n = 416 339), but for 2018, 2020, and 2021 it ranged from 259 000 to 297 000. Suspensions varied between 10.8% (2019) and 6.9% (2021), with the leading cause being patient-related. When analyzing the number of cases canceled monthly by facility, we saw that the leading cause was trade union-related. The maximum throughput of a ward intended for elective surgery was reached in 2019 and was 2.5 surgeries; in 2018, 2020 and 2021, the throughput borders on two surgeries per ward enabled for elective surgery. The percentage of ward time occupied during working hours by contract day varies between 80.7% (2018) and 56.8% (2020). Conclusions: All the parameters found and estimated in this study show that there is an inefficient utilization of operating rooms in Chilean public healthcare facilities.

Objetivo: El uso eficiente de pabellones destinados a cirugías electivas es fundamental para resolver patologías en lista de espera quirúrgica. El objetivo general de este estudio es estimar la eficiencia del uso de pabellones en el sistema de salud público de Chile entre los años 2018 y 2021. Métodos: El diseño fue un estudio ecológico. Se analizó la Sección A.21 de la base de datos construida por los resúmenes estadísticos mensuales que cada establecimiento de la red de salud pública reportó al Ministerio de Salud de Chile entre 2018 y 2021. Se extrajeron los datos de la subsección A, E y F: dotación de pabellones, total de cirugías electivas por especialidad, número y causas de suspensión de cirugías electivas. Luego se estimó el rendimiento quirúrgico en horario hábil y el porcentaje de ocupación horaria respecto de una jornada laboral. Adicionalmente, se hizo un análisis por región con datos de 2021. Resultados: El porcentaje de pabellones electivos respecto de los en dotación varió entre 81,1 y 94,1%; mientras que los habilitados respecto de los en dotación varió entre 70,5 y 90,4% durante 2018 y 2021. El número total de cirugías fue más alto en 2019 (n = 416 339), pero en 2018, 2020 y 2021 variaron entre 259 y 297 mil cirugías. Las suspensiones varían entre 10,8 (2019) y 6,9%w(2021), siendo la principal causa de suspensión atribuida al "paciente". Al analizar la cantidad de pacientes suspendidos mensualmente por institución, se observa que la principal causa es "gremial". El rendimiento máximo de un pabellón destinado a cirugía electiva se alcanzó en 2019 y fue de 2,5 cirugías; mientras que en 2018, 2020 y 2021 el rendimiento bordea las dos cirugías por pabellón habilitado para cirugía electiva. El porcentaje de tiempo de pabellón ocupado en horario hábil respecto a una jornada de contrato varía entre 80,7 (2018) y 56,8% (2020). Conclusiones: Todos los parámetros encontrados y estimados en este estudio muestran que el uso de pabellones en el sistema público de Chile es ineficiente.

Estimación de la eficiencia del uso de pabellones electivos en el sistema de salud público chileno entre 2018 y 2021 / Efficiency estimation on the use of elective surgical theaters in the Chilean public health system from 2018 to 2021

Objective The efficient use of wards intended for elective surgeries is essential to resolve cases on the surgical waiting list. This study aims to estimate the efficiency of ward use in the Chilean public health system between 2018 and 2021. Methods The design was an ecological study. Section A.21 of the database constructed by the monthly statistical summaries that each public health network facility reported to the Ministry of Health between 2018 and 2021 was analyzed. Data from subsections A, E and F were extracted: ward staffing, total elective surgeries by specialty, number and causes of suspension of elective surgeries. Then, the surgical performance during working hours and the percentage of hourly occupancy for a working day was estimated. Additionally, an analysis was made by region with data from 2021. Results The percentage of elective wards in use ranged from 81.1% to 94.1%, while those enabled for those staffing ranged from 70.5% to 90.4% during 2018 and 2021. The total number of surgeries was highest in 2019 (n = 416 339), but for 2018, 2020, and 2021 it ranged from 259 000 to 297 000. Suspensions varied between 10.8% (2019) and 6.9% (2021), with the leading cause being patient-related. When analyzing the number of cases canceled monthly by facility, we saw that the leading cause was trade union-related. The maximum throughput of a ward intended for elective surgery was reached in 2019 and was 2.5 surgeries; in 2018, 2020 and 2021, the throughput borders on two surgeries per ward enabled for elective surgery. The percentage of ward time occupied during working hours by contract day varies between 80.7% (2018) and 56.8% (2020). Conclusions All the parameters found and estimated in this study show that there is an inefficient utilization of operating rooms in Chilean public healthcare facilities.

Objetivo El uso eficiente de pabellones destinados a cirugías electivas es fundamental para resolver patologías en lista de espera quirúrgica. El objetivo general de este estudio es estimar la eficiencia del uso de pabellones en el sistema de salud público de Chile entre los años 2018 y 2021. Métodos El diseño fue un estudio ecológico. Se analizó la Sección A.21 de la base de datos construida por los resúmenes estadísticos mensuales que cada establecimiento de la red de salud pública reportó al Ministerio de Salud de Chile entre 2018 y 2021. Se extrajeron los datos de la subsección A, E y F: dotación de pabellones, total de cirugías electivas por especialidad, número y causas de suspensión de cirugías electivas. Luego se estimó el rendimiento quirúrgico en horario hábil y el porcentaje de ocupación horaria respecto de una jornada laboral. Adicionalmente, se hizo un análisis por región con datos de 2021. Resultados El porcentaje de pabellones electivos respecto de los en dotación varió entre 81,1 y 94,1%; mientras que los habilitados respecto de los en dotación varió entre 70,5 y 90,4% durante 2018 y 2021. El número total de cirugías fue más alto en 2019 (n = 416 339), pero en 2018, 2020 y 2021 variaron entre 259 y 297 mil cirugías. Las suspensiones varían entre 10,8 (2019) y 6,9%w(2021), siendo la principal causa de suspensión atribuida al "paciente". Al analizar la cantidad de pacientes suspendidos mensualmente por institución, se observa que la principal causa es "gremial". El rendimiento máximo de un pabellón destinado a cirugía electiva se alcanzó en 2019 y fue de 2,5 cirugías; mientras que en 2018, 2020 y 2021 el rendimiento bordea las dos cirugías por pabellón habilitado para cirugía electiva. El porcentaje de tiempo de pabellón ocupado en horario hábil respecto a una jornada de contrato varía entre 80,7 (2018) y 56,8% (2020). Conclusiones Todos los parámetros encontrados y estimados en este estudio muestran que el uso de pabellones en el sistema público de Chile es ineficiente.

Randomized clinical trial comparing pericapsular nerve group (PENG) block and periarticular local anesthetic infiltration for total hip arthroplasty.

BACKGROUND: This randomized trial compared pericapsular nerve group block and periarticular local anesthetic infiltration in patients undergoing primary total hip arthroplasty. We hypothesized that, compared with pericapsular nerve group block, periarticular local anesthetic infiltration would decrease the postoperative incidence of quadriceps weakness at 3 hours fivefold (ie, from 45% to 9%). METHODS: Sixty patients undergoing primary total hip arthroplasty under spinal anesthesia were randomly allocated to receive a pericapsular nerve group block (n=30) using 20 mL of adrenalized bupivacaine 0.50%, or periarticular local anesthetic infiltration (n=30) using 60 mL of adrenalized bupivacaine 0.25%. Both groups also received 30 mg of ketorolac, either intravenously (pericapsular nerve group block) or periarticularly (periarticular local anesthetic infiltration), as well as 4 mg of intravenous dexamethasone.Postoperatively, a blinded evaluator carried out sensory assessment and motor assessment (knee extension and hip adduction) at 3, 6 and 24 hours. Furthermore, the blinded observer also recorded static and dynamic pain scores at 3, 6, 12, 18, 24, 36 and 48 hours; time to first opioid request; cumulative breakthrough morphine consumption at 24 hours and 48 hours; opioid-related side effects; ability to perform physiotherapy at 6, 24 and 48 hours; as well as length of stay. RESULTS: There were no differences in quadriceps weakness at 3 hours between pericapsular nerve group block and periarticular local anesthetic infiltration (20% vs 33%; p=0.469). Furthermore, no intergroup differences were found in terms of sensory block or motor block at other time intervals; time to first opioid request; cumulative breakthrough morphine consumption; opioid-related side effects; ability to perform physiotherapy; and length of stay. Compared with pericapsular nerve group block, periarticular local anesthetic infiltration resulted in lower static pain scores (at all measurement intervals) and dynamic pain scores (at 3 and 6 hours). CONCLUSION: For primary total hip arthroplasty, pericapsular nerve group block and periarticular local anesthetic infiltration result in comparable rates of quadriceps weakness. However, periarticular local anesthetic infiltration is associated with lower static pain scores (especially during the first 24 hours) and dynamic pain scores (first 6 hours). Further investigation is required to determine the optimal technique and local anesthetic admixture for periarticular local anesthetic infiltration. TRIAL REGISTRATION NUMBER: NCT05087862.

Radiografía al acceso en artroplastia de rodilla entre los beneficiarios del Fondo Nacional de Salud entre 2004 y 2021 / Access to knee arthroplasty among National Health Fund beneficiaries in Chile between 2004 and 2021

Introducción La artrosis de rodilla es una patología que afecta la calidad de vida, siendo la artroplastía de rodilla un tratamiento costo-efectivo para la etapa severa de esta enfermedad. El acceso a artroplastia de rodilla es un indicador de salud de la Organización de Cooperación y Desarrollo Económico. Los objetivos de este estudio son determinar la incidencia de artroplastia de rodilla entre 2004 y 2021 en los beneficiarios del Fondo Nacional de Salud en Chile, la proporción que se operaron en el sistema privado y estimar el gasto del bolsillo del paciente para operarse. Método Estudio transversal. Se utilizó la base de datos del Departamento de Estadística e Información de Salud. Se pesquisaron pacientes que egresaron de un centro de salud chileno que fueron intervenidos por artroplastia rodilla entre 2004 y 2021. Se analizó la proporción de pacientes por tramo del Fondo Nacional de Salud y si se realizó su cirugía en establecimiento de la red pública o privada. Resultados De las 31 526 intervenciones de artroplastia de rodilla, 21 248 (67,38%) fueron realizadas en pacientes del Fondo Nacional de Salud y 16 238 en instituciones públicas (51,49%). Los pacientes de dicho fondo presentan un alza sistemática en el volumen de artroplastías de rodilla hasta 2019, pero disminuyeron en 2020 y 2021 un 68% y un 51%. Del total de pacientes del sistema público operados de artroplastia de rodilla, 856 (9%) pertenecían al tramo A1, al tramo B 12 806 (60%), al tramo C 2044 (10%) y al tramo D 4421 (21%). Se estimó que el gasto incurrido por estos pacientes varía entre el 24,4 y 27,2%. Las proporciones históricas de acceso en instituciones privadas a esta cirugía son en el tramo A 7%, tramo B 13%, tramo C 24% y tramo D 52%. Conclusión El 50% de las cirugías de artroplastía de rodilla se realizan en instituciones públicas y dos tercios se realizan en pacientes del Fondo Nacional de Salud. El 46% de los tramos C y D se operaron en el sistema privado. La pandemia ha aumentado la brecha de acceso, lo que ha provocado un alza significativa en la proporción de pacientes del Fondo Nacional de Salud de los tramos B, C y D que han migrado al sistema privado para acceder a esta cirugía.

Introduction Knee osteoarthritis affects the quality of life, with knee arthroplasty being a cost-effective treatment for the severe stage of this disease. Access to knee arthroplasty is a health indicator of the Organisation for Economic Co-operation and Development. The objectives of this study are to determine the incidence of knee arthroplasty between 2004 and 2021 in beneficiaries of the National Health Fund in Chile, the proportion of patients who underwent surgery in the private system, and to estimate the patient's out-of-pocket expenditure for surgery. Methods Cross-sectional study. We used the Department of Statistics and Health Information database. Patients discharged from a Chilean health center who underwent knee arthroplasty surgery between 2004 and 2021 were investigated. We analyzed the proportion of patients by their National Health Fund category and whether their surgery was performed in public or private network facilities. Results Of the 31 526 knee arthroplasty procedures, 21 248 (67.38%) were performed on National Health Fund patients and 16 238 in public institutions (51.49%). Patients from the National Health Fund showed a systematic increase in knee arthroplasty volume until 2019 but decreased in 2020 and 2021 by 68% and 51%. Of the total number of patients in the public system operated on for knee arthroplasty, 856 (9%) belonged to group A1, 12 806 (60%) to group B, 2044 (10%) to group C, and 4421 (21%) to group D. The expenditure incurred by these patients was estimated to vary between 24.4% and 27.2%. The historical proportions of access to this surgery in private institutions are 7% in group A, 13% in group B, 24% in group C, and 52% in group D. Conclusion Fifty percent of knee arthroplasty surgeries are performed in public institutions, and two-thirds are performed on patients of the National Health Fund. Forty-six percent of the C and D groups were operated in the private system. The pandemic has increased the access gap, leading to a substantial increase in the proportion of patients from the National Health Fund of the B, C, and D groups who have migrated to the private system to access this surgery.

Access to knee arthroplasty among National Health Fund beneficiaries in Chile between 2004 and 2021. / Radiografía al acceso en artroplastia de rodilla entre los beneficiarios del Fondo Nacional de Salud entre 2004 y 2021.

Introduction: Knee osteoarthritis affects the quality of life, with knee arthroplasty being a cost-effective treatment for the severe stage of this disease. Access to knee arthroplasty is a health indicator of the Organisation for Economic Co-operation and Development. The objectives of this study are to determine the incidence of knee arthroplasty between 2004 and 2021 in beneficiaries of the National Health Fund in Chile, the proportion of patients who underwent surgery in the private system, and to estimate the patient's out-of-pocket expenditure for surgery. Methods: Cross-sectional study. We used the Department of Statistics and Health Information database. Patients discharged from a Chilean health center who underwent knee arthroplasty surgery between 2004 and 2021 were investigated. We analyzed the proportion of patients by their National Health Fund category and whether their surgery was performed in public or private network facilities. Results: Of the 31 526 knee arthroplasty procedures, 21 248 (67.38%) were performed on National Health Fund patients and 16 238 in public institutions (51.49%). Patients from the National Health Fund showed a systematic increase in knee arthroplasty volume until 2019 but decreased in 2020 and 2021 by 68% and 51%. Of the total number of patients in the public system operated on for knee arthroplasty, 856 (9%) belonged to group A1, 12 806 (60%) to group B, 2044 (10%) to group C, and 4421 (21%) to group D. The expenditure incurred by these patients was estimated to vary between 24.4% and 27.2%. The historical proportions of access to this surgery in private institutions are 7% in group A, 13% in group B, 24% in group C, and 52% in group D. Conclusion: Fifty percent of knee arthroplasty surgeries are performed in public institutions, and two-thirds are performed on patients of the National Health Fund. Forty-six percent of the C and D groups were operated in the private system. The pandemic has increased the access gap, leading to a substantial increase in the proportion of patients from the National Health Fund of the B, C, and D groups who have migrated to the private system to access this surgery.

Introducción: La artrosis de rodilla es una patología que afecta la calidad de vida, siendo la artroplastía de rodilla un tratamiento costo-efectivo para la etapa severa de esta enfermedad. El acceso a artroplastia de rodilla es un indicador de salud de la Organización de Cooperación y Desarrollo Económico. Los objetivos de este estudio son determinar la incidencia de artroplastia de rodilla entre 2004 y 2021 en los beneficiarios del Fondo Nacional de Salud en Chile, la proporción que se operaron en el sistema privado y estimar el gasto del bolsillo del paciente para operarse. Método: Estudio transversal. Se utilizó la base de datos del Departamento de Estadística e Información de Salud. Se pesquisaron pacientes que egresaron de un centro de salud chileno que fueron intervenidos por artroplastia rodilla entre 2004 y 2021. Se analizó la proporción de pacientes por tramo del Fondo Nacional de Salud y si se realizó su cirugía en establecimiento de la red pública o privada. Resultados: De las 31 526 intervenciones de artroplastia de rodilla, 21 248 (67,38%) fueron realizadas en pacientes del Fondo Nacional de Salud y 16 238 en instituciones públicas (51,49%). Los pacientes de dicho fondo presentan un alza sistemática en el volumen de artroplastías de rodilla hasta 2019, pero disminuyeron en 2020 y 2021 un 68% y un 51%. Del total de pacientes del sistema público operados de artroplastia de rodilla, 856 (9%) pertenecían al tramo A1, al tramo B 12 806 (60%), al tramo C 2044 (10%) y al tramo D 4421 (21%). Se estimó que el gasto incurrido por estos pacientes varía entre el 24,4 y 27,2%. Las proporciones históricas de acceso en instituciones privadas a esta cirugía son en el tramo A 7%, tramo B 13%, tramo C 24% y tramo D 52%. Conclusión: El 50% de las cirugías de artroplastía de rodilla se realizan en instituciones públicas y dos tercios se realizan en pacientes del Fondo Nacional de Salud. El 46% de los tramos C y D se operaron en el sistema privado. La pandemia ha aumentado la brecha de acceso, lo que ha provocado un alza significativa en la proporción de pacientes del Fondo Nacional de Salud de los tramos B, C y D que han migrado al sistema privado para acceder a esta cirugía.

Gonyautoxins 2/3 Local Periarticular Injection for Pain Management after Total Knee Arthroplasty: A Double-Blind, Randomized Study.

The purpose of this study was to compare the efficacy of periarticular infiltration of gonyautoxin 2/3 (GTX 2/3) and a mixture of levobupivacaine, ketorolac, and epinephrine for pain management after total knee arthroplasty (TKA). Forty-eight patients were randomly allocated to receive periarticular infiltration of 40 µg GTX 2/3 (n = 24) diluted in 30 mL of sodium chloride 0.9% (study group) or a combination of 300 mg of levobupivacaine, 1 mg of epinephrine, and 60 mg ketorolac (n = 24) diluted in 150 mL of sodium chloride 0.9% (control group). Intraoperative anesthetic and surgical techniques were identical for both groups. Postoperatively, all patients received patient-controlled analgesia (morphine bolus of 1 mg; lockout interval of 8 minutes), acetaminophen, and ketoprofen for 72 hours. A blinded investigator recorded morphine consumption, which was the primary outcome. Also, the range of motion (ROM) and static and dynamic pain were assessed at 6, 12, 36, and 60 hours after surgery. The incidence of adverse events, time to readiness for discharge, and length of hospital stay were also recorded. The median of total cumulative morphine consumption was 16 mg (range, 0-62 mg) in the GTX 2/3 group and 9 mg (range, 0-54 mg) in control group, which did not reach statistical difference (median test, p = 0.40). Furthermore, static and dynamic pain scores were similar at all time intervals. GTX 2/3 was inferior in range of motion at 6 and 12 hours; nevertheless, we noted no difference after 36 hours. No differences between groups were found in terms of complications, side effects, or length of hospital stay. No significant differences were found between groups in terms of breakthrough morphine requirement. However, local anesthetic use resulted in an increased ROM in the first 12 hours. This prospective randomized clinical trial shows that GTX 2/3 is a safe and efficient drug for pain control after TKA; nevertheless, more studies using GTX 2/3 with larger populations are needed to confirm the safety profile and efficiency. This is level 1 therapeutic study, randomized, double-blind clinical trial.

Impact of COVID-19 outbreak in knee arthroplasty in Chile: a cross-sectional, national registry-based analysis. / Impacto de la pandemia por COVID-19 en la incidencia de artroplastías de rodilla en Chile: estudio transversal basado en registro nacional.

Introduction: The need for beds and health personnel to treat coronavirus (COVID- 19) patients has led to the suspension of many elective sur-geries in Chile, including knee arthroplasties. This study aims to determine the incidence of knee arthroplasty in 2020, reflecting the effect of the COVID- 19 pandemic, and estimate the cost and time it would take to recover the waiting list prior to March 2020. Methods: A cross- sectional study was designed. We analyzed databases from The Department of Statistics and Health Information databases from Chile for 2019 and 2020, identifying patients with surgical discharges associated with knee arthroplasty codes. We estimated the time it would take to recover the surgeries unperformed in 2020 by simulating a monthly workload increase from the 2019 baseline. The costs of knee arthroplasty paid by the National Health Fund to institutions were estimated by diagnosis-related groups. Results: We found that the incidence rate of knee arthroplasty in 2020 decreased by 64% compared with 2019. The impact was higher in the public system (68%) and the National Health Found (63%). A simulated increase in knee arthroplasty productivity by 30% would allow recovering the postponed knee arthroplasty surgeries in 27 months, at a monthly cost to the public system of 318 million Chilean pesos (378 thousand US dollars). Conclusions: The incidence rate of knee arthroplasty during 2020 decreased by 64%, revealing the extensive waiting line for people with knee osteoarthritis. An increase between 20- 40% in productivity compared with 2019 would allow recovering the unperformed surgeries in 20 to 41 months, at a monthly cost to the public network between 210 and 425 million Chilean pesos (250 to 506 thousand US dollars).

Introducción: Debido a la respuesta de los servicios de salud a la pandemia por COVID- 19, se han suspendido cirugías electivas como la artroplastía de rodilla. El objetivo de este estudio es determinar la incidencia de artroplastías de rodilla en 2020 reflejando el efecto de la pandemia, y estimar el tiempo y el costo para recuperar la situación de lista de espera previa a marzo de 2020. Métodos: Estudio transversal. Se analizaron las bases de datos del Departamento de Estadística e Información en Salud de Chile de 2019 y 2020, identificando pacientes asociados a códigos de artroplastía de rodilla. Se calculó el número mensual de artroplastias realizadas durante 2019 para estimar el tiempo que tomará recuperar las cirugías no realizadas en 2020. El costo asociado a artroplastía de rodilla se hizo según el método de pago utilizado por el Fondo Nacional de Salud estimado por grupos relacionados por diagnóstico. Resultados: En 2020 la tasa de incidencia de artroplastía de rodilla por 100 000 habitantes disminuyó 64% comparado con 2019. El impacto fue mayor en el sistema público (68%) y en beneficiarios del Fondo Nacional de Salud (63%). Un aumento en la productividad en 30% respecto a 2019 haría que en 27 meses se recuperen las cirugías no realizadas en 2020, significando un costo adicional mensual en el sistema público de 318 262 530 pesos chilenos (equivalentes a 378 mil dólares americanos, USD). Conclusiones: Hubo una importante disminución de la tasa de artroplastías de rodilla en 2020, estimándose una caída del 64% en la incidencia por 100 000 habitantes. Esto muestra un incremento importante de personas que esperan la resolución a la artrosis de rodilla. Un aumento entre 20 y 40% respecto de 2019 permitiría recuperar las cirugías no realizadas en un plazo entre 20 y 41 meses, a un costo mensual en el sistema público que varía entre 210 y 425 millones pesos chilenos (de 250 a 506 mil dólares americanos, USD).

Impacto de la pandemia por COVID-19 en la incidencia de artroplastías de rodilla en Chile: estudio transversal basado en registro nacional / Impact of COVID-19 outbreak in knee arthroplasty in Chile: a cross-sectional, national registry-based analysis

Introducción Debido a la respuesta de los servicios de salud a la pandemia por COVID- 19, se han suspendido cirugías electivas como la artroplastía de rodilla. El objetivo de este estudio es determinar la incidencia de artroplastías de rodilla en 2020 reflejando el efecto de la pandemia, y estimar el tiempo y el costo para recuperar la situación de lista de espera previa a marzo de 2020. Métodos Estudio transversal. Se analizaron las bases de datos del Departamento de Estadística e Información en Salud de Chile de 2019 y 2020, identificando pacientes asociados a códigos de artroplastía de rodilla. Se calculó el número mensual de artroplastias realizadas durante 2019 para estimar el tiempo que tomará recuperar las cirugías no realizadas en 2020. El costo asociado a artroplastía de rodilla se hizo según el método de pago utilizado por el Fondo Nacional de Salud estimado por grupos relacionados por diagnóstico. Resultados En 2020 la tasa de incidencia de artroplastía de rodilla por 100 000 habitantes disminuyó 64% comparado con 2019. El impacto fue mayor en el sistema público (68%) y en beneficiarios del Fondo Nacional de Salud (63%). Un aumento en la productividad en 30% respecto a 2019 haría que en 27 meses se recuperen las cirugías no realizadas en 2020, significando un costo adicional mensual en el sistema público de 318 262 530 pesos chilenos (equivalentes a 378 mil dólares americanos, USD). Conclusiones Hubo una importante disminución de la tasa de artroplastías de rodilla en 2020, estimándose una caída del 64% en la incidencia por 100 000 habitantes. Esto muestra un incremento importante de personas que esperan la resolución a la artrosis de rodilla. Un aumento entre 20 y 40% respecto de 2019 permitiría recuperar las cirugías no realizadas en un plazo entre 20 y 41 meses, a un costo mensual en el sistema público que varía entre 210 y 425 millones pesos chilenos (de 250 a 506 mil dólares americanos, USD).

Introducción Debido a la respuesta de los servicios de salud a la pandemia por COVID- 19, se han suspendido cirugías electivas como la artroplastía de rodilla. El objetivo de este estudio es determinar la incidencia de artroplastías de rodilla en 2020 reflejando el efecto de la pandemia, y estimar el tiempo y el costo para recuperar la situación de lista de espera previa a marzo de 2020. Métodos Estudio transversal. Se analizaron las bases de datos del Departamento de Estadística e Información en Salud de Chile de 2019 y 2020, identificando pacientes asociados a códigos de artroplastía de rodilla. Se calculó el número mensual de artroplastias realizadas durante 2019 para estimar el tiempo que tomará recuperar las cirugías no realizadas en 2020. El costo asociado a artroplastía de rodilla se hizo según el método de pago utilizado por el Fondo Nacional de Salud estimado por grupos relacionados por diagnóstico. Resultados En 2020 la tasa de incidencia de artroplastía de rodilla por 100 000 habitantes disminuyó 64% comparado con 2019. El impacto fue mayor en el sistema público (68%) y en beneficiarios del Fondo Nacional de Salud (63%). Un aumento en la productividad en 30% respecto a 2019 haría que en 27 meses se recuperen las cirugías no realizadas en 2020, significando un costo adicional mensual en el sistema público de 318 262 530 pesos chilenos (equivalentes a 378 mil dólares americanos, USD). Conclusiones Hubo una importante disminución de la tasa de artroplastías de rodilla en 2020, estimándose una caída del 64% en la incidencia por 100 000 habitantes. Esto muestra un incremento importante de personas que esperan la resolución a la artrosis de rodilla. Un aumento entre 20 y 40% respecto de 2019 permitiría recuperar las cirugías no realizadas en un plazo entre 20 y 41 meses, a un costo mensual en el sistema público que varía entre 210 y 425 millones pesos chilenos (de 250 a 506 mil dólares americanos, USD).

Cohorte histórica de artroplastia unicompartimental de rodilla en un hospital universitario chileno / Historical cohort of unicompartmental knee arthroplasty in a Chilean university hospital

OBJETIVO Describir el resultado funcional informado por el paciente de una cohorte de pacientes sometidos a artroplastia unicompartimental de rodilla (AUR) en un hospital universitario chileno. MÉTODOS Se diseñó un estudio de cohorte histórica. Se incluyeron todos los pacientes que se sometieron a AUR de platillo fijo entre 2003 y 2019. Un evaluador independiente se puso en contacto con los pacientes en junio de 2020. Se utilizó el índice de artritis de las universidades de Western Ontario y McMaster (WOMAC) para comparar los procedimientos de AUR (medial o lateral), la edad (mayor o menor de 70 años), y el seguimiento (más o menos de 5 años). RESULTADOS Se incluyeron 78 pacientes, en un total de 94 AURs. La mediana de edad fue de 64 años (rango: 43 a 85 años). Hubo 72 (76,6%) casos de AUR medial. Un paciente necesitó revisión para artroplastia total de rodilla (ATR). Un total de 60 pacientes (76,9%), correspondientes a 72 AURs (76,7%), fueron contactados con éxito por teléfono para el seguimiento final. La mediana del puntaje en los dominios del WOMAC fue: dolor ­ 1 (rango: 0 a 12); rigidez ­ 0 (rango: 0 a 4); y función física ­ 2 (rango: 0 a 29). La mediana del puntaje total en el WOMAC fue de 4 (rango: 0 a 44). Los pacientes sometidos a AUR lateral lograron mejores puntuaciones funcionales (p » 0,0432), y el puntaje total en el WOMAC fue similar en pacientes mayores o menores de 70 años (p » 0,3706). CONCLUSIONES La AUR es un tratamiento eficaz y reproducible para pacientes con artrosis de rodilla unicompartimental. La edad parece no afectar los resultados funcionales, y la AUR es un tratamiento eficaz en pacientes mayores de 70 años. Estos resultados deberían animar a los cirujanos de rodilla a aprender esta técnica y a los responsables de las políticas de salud pública a considerar la AUR para la osteoartritis de rodilla.

PURPOSE To describe the patient-reported functional outcome of a cohort of patients undergoing unicompartmental knee arthroplasty (UKA) in a Chilean university hospital. METHODS A historical cohort study was designed. All patients who underwent fixedbearing UKA between 2003 and 2019 were included. An independent evaluator contacted the patients in June 2020. The Western Ontario and McMaster Universities Arthritis Index (WOMAC) was used to compare UKA procedures (medial or lateral), age (over or under 70 years), and follow up (longer or shorter than 5 years). RESULTS A total of 78 patients, corresponding to 94 UKAs, were included. The median age was 64 years (range: 43 to 85 years). There were 72 (76.6%) cases of medial UKA. One patient needed revision to total knee arthoplasty (TKA). A total of 60 patients (76.9%), corresponding to 72 UKAs, were successfully contacted by phone for the final follow-up. The median scores on the WOMAC domains were: pain ­ 1 (range: 0 to 12); stiffness ­0 (range: 0 to 4); and physical function ­ 2 (range: 0 to 29). The median total score on the WOMAC was 4 (range: 0 to 44). Patients submitted to lateral UKA had better functional scores (p » 0.0432), and the total WOMAC score was similar among patients older or younger than 70 years of age (p » 0.3706). CONCLUSIONS For patients with unicompartmental knee osteoarthritis, UKA is an effective and reproducible treatment. Age does not seem to affect the functional results, and UKA is an effective treatment in patients over 70 years old. These results should encourage knee surgeons to learn this technique and those responsible for public health policies to consider UKA for knee osteoarthritis

Scissor Position of the Orthopedic Table for the Resolution of Intertrochanteric and Subtrochanteric Hip Fractures.

During the surgical resolution of intertrochanteric and subtrochanteric hip fractures on an orthopedic table, a fluoroscope needs to be used in orthogonal planes. This requires that the contralateral leg does not obstruct the radioscopic view, so patients are often placed in a hemilithotomy position. This position, also called the Lloyd-Davis position, involves hip flexion, hip abduction, hip external rotation, and knee flexion. However, rare complications, such as acute leg posterior compartment syndrome, have been described. In addition, patients with severe osteoarthritis and joint stiffness or a history of total hip arthroplasty may have difficulty achieving this position, and the well leg may be at risk of injury in a hemilithotomy position. A previously described position called the "scissor position" is, in our opinion, a safer and more efficient technique for placing the well leg on the orthopedic table, using only a pillow and a self-adhesive compression bandage. This simple position allows a lateral fluoroscopic view of the injured femur without overlapping or interference from the other limb.

Impact of the COVID-19 Outbreak on Orthopedic Surgery: A Nationwide Analysis of the First Pandemic Year.

Purpose To analyze the impact of the coronavirus disease 2019 (COVID-19) outbreak during the first pandemic year in a single country. Methods A cross-sectional study was designed. The free access database of the Chilean Department of Statistics and Health Information (DEIS) was used to compare the number of orthopedic procedures between 2019 and 2020. Country mobility was exported from the Institute of Complex Engineering Systems (ISCI) free-access database; this corresponds to a direct measurement of the degree of confinement of the country. Spearman correlation (rho) was used to analyze the total monthly COVID infection trend and mobility to orthopedics procedures. Results The number of orthopedic surgeries fell by 22.8% during the first year of the pandemic. All surgical procedures were adversely affected, with the fracture/trauma surgeries being the least affected. The maximum adverse impact was seen in knee arthroplasty (-64%), followed by hip arthroplasty (-41%) and knee ligament reconstruction (-44%). The number of orthopedic procedures had a mild correlation to the monthly number of COVID-19 cases (rho=-0.53, p=0.08) and a strong correlation with the country's mobility (rho=0.94, p=0.0001). Conclusions The COVID-19 outbreak diminished the number of orthopedic procedures during 2020, and the impact was directly correlated to the country's mobility. The public health network did have a more significant adverse impact in elective surgeries due to a slower recovery than private institutions. An increase in the waiting list should be expected, which will widen the difference in access to orthopedic surgery in Chile.

Validation of the Spanish version of the Goodman score in total hip arthroplasty.

PURPOSE: Currently, patient-reported outcome measures (PROMs) are the standard instruments used to compare arthroplasty results. Goodman et al. recently published a well-constructed scale with excellent psychometric properties that can be quickly administered. The main objective of our study was to translate, culturally adapt, and validate a Spanish version of the Goodman questionnaire in patients who underwent total hip arthroplasty (THA). METHODS: The original Goodman scale was translated into Spanish and cross-culturally adapted. Then, the data from this version were tested for psychometric quality. We designed a cross-sectional study for data collection. This study enrolled 2 institutions. Patients who underwent hip replacement due to primary osteoarthritis secondary to dysplasia between 1 January 2018 and 31 December 2019 were included. A total of 153 patients were contacted twice to record the Goodman and Oxford hip scales (OHS) to assess the validity of the questionnaire. Reliability was tested using the Cronbach's alpha, Concordance using 3 test: intraclass correlation coefficient (ICC), Lin's concordance correlation coefficient (CCC), and the Bradley-Blackwood F test. The spearman correlation was used to asses correlation between the OHS and the Spanish-adapted Goodman scale. RESULTS: The overall satisfaction after THA was reported to be "very satisfied" by 137 patients (75%), and only 14 patients reported some degree of dissatisfaction (6%). The improvement in quality of life was reported to be "more than I ever dreamed possible" by 41% patients. Cronbach's alpha was acceptable, reaching a coefficient of 0.95 (95% confidence interval, 0.82-1). No statistical difference (t test, p = 0.55) was found in the original version, with great internal validity. Test re-test concordance was optimal among the 3 tests used. A moderate correlation was found between the OHS and the Spanish-adapted Goodman scale. CONCLUSION: The Spanish version of the Goodman questionnaire in THA is a reliable, consistent, and feasible scale to evaluate patient satisfaction and improvement in the quality of life in Spanish speakers.

Evolución epidemiológica de la artroplastia de cadera y rodilla durante 17 años en pacientes con artrosis severa en un hospital Chileno / Evolution of hip and knee arthroplasty epidemiology in a single hospital of Chile: a 17 years overview

INTRODUCCIÓN: La artroplastia total de cadera (ATC), es la cirugía del siglo XX por el impacto en la calidad de vida. Por su parte, la artroplastia de rodilla (AR), ha demostrado ser un procedimiento costo-efectivo en gonartrosis. OBJETIVO: Describir la evolución de ATC y AR, en cuanto a número de procedimientos, edad y género en pacientes operados en un hospital general. MÉTODO: Estudio transversal analítico. Fueron incluidos todos los procedimientos realizados en un único centro, entre enero de 2002 y diciembre 2018, que estuvieran registrados por los códigos de prestación Fonasa 2104129 y 2104153. Fueron excluidos todos los procedimientos de revisión de artroplastia, tumores y fracturas. Se realizó un análisis de correlación de Spearman, se estableció una significancia de 0,05. RESULTADOS: Fueron incluidos 3270 procedimientos, 1975 corresponden a ATC (60,4%) y 1295 AR (39,6%). El número de ATC ha ido aumentando, en 2002 fueron realizados 122, mientras que en 2018, fueron 164. Por su parte, las AR también aumentaron, en 2002 fueron realizadas 40, mientras que en 2018 fueron 155. La proporción ATC/AR ha disminuido significativamente. La edad promedio ha disminuido en AR y aumentado en ATC, sin significación estadística. En ATC, se observa un incremento en la proporción de hombres operados. CONCLUSIONES: El perfil epidemiológico de los pacientes operados de artroplastia ha cambiado significativamente. La epidemiología mundial y la de este estudio muestran un significativo incremento de pacientes que requieren AR, por lo cual, parece importante incluir ese procedimiento en las necesidades sanitarias a satisfacer, en el diseño de nuevas políticas públicas.

OBJECTIVE: To describe the evolution of hip and knee arthroplasty in a general hospital, in terms of number of procedures, average age and gender. METHOD: Analytical cross-sectional study. All procedures performed between January 2002 and December 2018 in a single center were included. All procedures performed for revision surgery, tumors or fracture were excluded. The following data were obtained from the registry: age at the time of surgery, gender of the patient and year of the procedure. A Spearman correlation analysis was performed, a significance of 0.05 was established. RESULTS: 3270 procedures were included, 1975 correspond to hip arthroplasty (60.4%) and 1295 to knee arthroplasty (39.6%). The number of hip arthroplasty has increased over time, in 2002 a total of 122 procedures were performed and in 2018 there were 164. On the other hand, knee arthroplasty procedures have also increased, from 40 in 2002 to 155 in 2018. The ratio between hip and knee arthroplasty has been decreasing, this finding being significant. The average age has been decreasing in knee arthroplasty, meanwhile, decreasing in hip arthroplasty during the studied period. On the other hand, the proportion of men that underwent hip arthroplasty has been increasing over time. CONCLUSIONS: The number of knee arthroplasty has increased significantly, decreasing its difference with respect to the number of hip arthroplasty. An explosive increase in knee arthroplasty has been described in the literature, consistent with the outcomes of this study, so it seems important to include this procedure the new health public policies.

Análisis de la mortalidad tras una fractura de cadera en un período de 15 años: la mortalidad al año se correlaciona directamente con la mortalidad a los 2 años / Mortality trend over 15 years in hip fracture: mortality at 1 year directly correlates with mortality at 2 years

OBJETIVO: Evaluar la tendencia de la letalidad al año y a 2 años, tiempo de espera de cirugía y estadía hospitalaria en fractura de cadera entre 2002 y 2016. Además, evaluar la correlación entre letalidad a uno y dos años. MÉTODO: Diseño transversal. Fueron incluidos pacientes mayores de 60 años que ingresaron por fractura de cadera entre 2002 y 2016. Se solicitó al Registro Civil reportar si los pacientes estaban con vida al 30 de junio de 2019. La correlación de Spearman fue estimada para determinar la tendencia de la letalidad a uno y dos años, la edad, el tiempo de espera de cirugía, y la estadía hospitalaria durante el periodo estudiado. Además, una regresión linear fue estimada entre letalidad a un año y dos años. RESULTADOS: Fueron incluidos 961 fracturas de cadera. Se observó una tendencia a la disminución en la letalidad a 1 (rho » -0.23) y 2 años (rho » -0.29), en la proporción de hombres (rho » -0.25), en la estadía hospitalaria (rho » -0.06), y en el tiempo de espera de cirugía (rho » -0.11), sin alcanzar significancia estadística. La letalidad a 1 año fue de 0,17 (intervalo de confianza de 95% [IC95%]: 0,14 a 0,19), y a 2 años, de 0,26 (IC 95%: 0,23 a 0,29). Se estimó un R2 de 0,60 entre la letalidad a 1 y 2 años. CONCLUSIONES: La letalidad a uno y dos años, el tiempo de espera de cirugía, la edad de presentación, y la estadía hospitalaria no han variado significativamente en el periodo estudiado. Se observa una fuerte correlación entre la letalidad a uno y dos años, lo que sugiere un riesgo constante de mortalidad después de una fractura de cadera.

PURPOSE: To evaluate the trend in 1 and 2 years, the fatality rate, the waiting time for surgery, and the length of hospital stay in a single center between 2002 and 2016. Also, to evaluate the relationship between the one-year and two-year fatality rates. METHODS: A cross-sectional study. Patients older than 60 years of age who were admited due to hip fracture between 2002 and 2016 were included. A request was made to the Chilean National Civil Registry to determine if the patients were alive on June 30, 2019. The Spearman correlation was estimated to determine the trend of the one-year and two-year fatality rates, the age, the type of fracture, and the waiting time for surgery. Also, a linear regression analysis was estimated between the one-year and two-year fatality rates. RESULTS: A total of 961 hip fractures were included. From 2002 to 2016, a downward trend was found in the 1-year (rho » -0.23) and 2-year fatality rates (rho » -0.29), in the proportion of male patients (rho » -0.25), in the length of hospital stay (rho » -0.06), and in the waiting time for surgery (rho » -0.11), not reaching statistical difference. The 1-year fatality rate was of 0,17 (95% confidence interval [95%CI]: 0.14 to 0.19) and the 2-year fatality rate was of 0,26 (95%CI: 0.23 to 0.29). An R2 of 0.60 was estimated between the 1-year and 2-year fatality rates. CONCLUSIONS: The one-year and two-year fatality rates, the waiting time for surgery, and the length of hospital stay remained constant during the period analyzed. A strong correlation between the one-year and two-year fatality rates was found, which suggests a constant risk of death after hip fracture.