An explainable machine learning approach for hospital emergency department visits forecasting using continuous training and multi-model regression.

BACKGROUND AND OBJECTIVE: In the last years, the Emergency Department (ED) has become an important source of admissions for hospitals. Since late 90s, the number of ED visits has been steadily increasing, and since Covid19 pandemic this trend has been much stronger. Accurate prediction of ED visits, even for moderate forecasting time-horizons, can definitively improve operational efficiency, quality of care, and patient outcomes in hospitals. METHODS: In this paper we propose two different interpretable approaches, based on Machine Learning algorithms, to accurately forecast hospital emergency visits. The proposed approaches involve a first step of data segmentation based on two different criteria, depending on the approach considered: first, a threshold-based strategy is adopted, where data is divided depending on the value of specific predictor variables. In a second approach, a cluster-based ensemble learning is proposed, in such a way that a clustering algorithm is applied to the training dataset, and ML models are then trained for each cluster. RESULTS: The two proposed methodologies have been evaluated in real data from two hospital ED visits datasets in Spain. We have shown that the proposed approaches are able to obtain accurate ED visits forecasting, in short-term and also long-term prediction time-horizons up to one week, improving the efficiency of alternative prediction methods for this problem. CONCLUSIONS: The proposed forecasting approaches have a strong emphasis on providing explainability to the problem. An analysis on which variables govern the problem and are pivotal for obtaining accurate predictions is finally carried out and included in the discussion of the paper.

The Chemistry behind Catechol-Based Adhesion.

The adhesion of some marine organisms to almost any kind of surface in wet conditions has aroused increasing interest in recent decades. Numerous fundamental studies have been performed to understand the scientific basis of this behaviour, with catechols having been found to play a key role. Several novel bio-inspired adhesives and coatings with value-added performances have been developed by taking advantage of the knowledge gained from these studies. To date there has been no detailed overview focusing exclusively on the complex mode of action of these materials. The aim of this Review is to present recent investigations that elucidate the origin of the strong and versatile adsorption capacities of the catechol moiety and the effects of extrinsic factors that play important roles in the overall adhesion process, such as pH value, solvent, and the presence of metal ions. The aim is to detail the chemistry behind the astonishing properties of natural and synthetic catechol-based adhesive materials.

Ozonation of hospital raw wastewaters for cytostatic compounds removal. Kinetic modelling and economic assessment of the process.

The kinetics of the ozone consumption for the pretreatment of hospital wastewater has been analysed in order to determine the reaction rate coefficients between the ozone and the readily oxidisabled organic matter and cytostatic compounds. The wastewater from a medium size hospital was treated with ozone and peroxone methodologies, varying the ozone concentration, the reaction time and the hydrogen peroxide doses. The analysis shows that there are four cytostatic compounds, i.e. irinotecan, ifosfamide, cyclophosphamide and capecitabine, detected in the wastewaters and they are completely removed with reasonably short times after the ozone treatment. Considering the reactor geometry, the gas hydrodynamics, the mass transfer of ozone from gas to liquid and the reaction of all oxidisable compounds of the wastewater it is possible to determine the chemical ozone demand, COzD, of the sample as 256mgO3L(-1) and the kinetic rate coefficient with the dissolved organic matter as 8.4M(-1)s(-1). The kinetic rate coefficient between the ozone and the cyclophosphamide is in the order of 34.7M(-1)s(-1) and higher for the other cytostatics. The direct economic cost of the treatment was evaluated considering this reaction kinetics and it is below 0.3€/m(3) under given circumstances.

[Cost analysis of the use of botulinum toxin type A in Spain]. / Análisis de costes del uso de toxina botulínica A en España.

OBJECTIVE: To estimate treatment costs of blepharospasm, cervical dystonia(CD), upper limb spasticity (ULS) and spasticity in children with cerebral palsy (SCCP) with botulinum neurotoxin type A (BoNT-A) in Spain. METHOD: Annual BoNT-A treatment costs were calculated (2013 ex-factory price () applying RDL 8/2010 and RDL 9/2011 deductions), based on initial dose (id), average dose (ad) and maximum dose (md) according to Summary of Product Characteristics of Botox® (100U/50U), Dysport®(500U) and Xeomin® (100U) and considering the use of complete vials.In addition, annual treatment costs were calculated considering the useof vials in more than one patient and also patient population annual treatment costs based on diseases' prevalence. RESULTS: Annual BoNT-A treatment costs per patient were estimated at between 265 and 2,120 with savings from 10% to 55% accordingto the selected BoNT-A. CD and ULS treatment provided the greatest cost per patient. Botox® provided greater savings in ULS (id/ad), CD(id), and in blepharospasm and SCCP (id/ad/md). Dysport® treatment was less costly in CD (md) and ULS (md), while Xeomin® was in CD(ad). Based on the estimated treated population in Spain, the annual treatment costs ranged from 368,392 to 13,958,836 depending on indication, dose and BoNT-A considered. CONCLUSIONS: The appropriate BoNT-A choice would lead to considerable savings for the National Health System. Botox® would generate lower costs per patient than other BoNT-A products in 9 out of 12 scenarios considered.

Objetivo: Estimar el coste de tratamiento de blefarospasmo, distoníacervical (DC), espasticidad del brazo del adulto (EBA) yespasticidad del niño con parálisis cerebral infantil (EPCI) con laspresentaciones de neurotoxina botulínica tipo A (NTB-A) enEspaña.Método: Se calculó el coste anual de tratamiento con NTB-A(, 2013; PVL oficial publicado aplicando deducciones del RDL8/2010 y RDL 9/2011), en función de la dosis inicial (di), dosismedia (dm) y dosis máxima (dmax) en base a los viales porsesión según fichas técnicas de Botox® (100U y 50U), Dysport®(500U) y Xeomin® (100U), considerando los músculos comunesen cada indicación. Adicionalmente, se calculó el coste considerandola población total de pacientes según prevalencia y lareutilización de viales en más de un paciente.Resultados: El coste anual/paciente con NTB-A supondría entre265y 2.120con un ahorro entre el 10% y 55% según laNTB-A seleccionada. DC y EBA presentarían el mayor coste/paciente. Botox® generaría un menor coste en EBA (di/dm) y DC(di) y en blefarospasmo y EPCI (di/dm/dmax). Dysport® tiene elmenor coste en DC (dmax) y EBA (dmax) y Xeomin® en DC(dm). El coste anual por población según prevalencia suponeentre 368.392y 13.958.836según indicación, dosis y NTBAseleccionada.Conclusiones: Una selección adecuada de las presentaciones deNTB-A para cada indicación permitiría generar importantesahorros para el Sistema Nacional de Salud. Botox® conseguiríamenores costes anuales/paciente frente al resto de NTB-A en 9de los 12 escenarios considerados.

Análisis de costes del uso de toxina botulínica A en España / Cost analysis of the use of botulinum toxin type A in Spain

Objetivo: Estimar el coste de tratamiento de blefarospasmo, distonía cervical (DC), espasticidad del brazo del adulto (EBA) y espasticidad del niño con parálisis cerebral infantil (EPCI) con las presentaciones de neurotoxina botulínica tipo A (NTB-A) en España. Método: Se calculó el coste anual de tratamiento con NTB-A(Euros, 2013; PVL oficial publicado aplicando deducciones del RDL8/2010 y RDL 9/2011), en función de la dosis inicial (di), dosis media (dm) y dosis máxima (dmax) en base a los viales por sesión según fichas técnicas de Botox(R) (100U y 50U), Dysport(R)(500U) y Xeomin® (100U), considerando los músculos comunes en cada indicación. Adicionalmente, se calculó el coste considerando la población total de pacientes según prevalencia y la reutilización de viales en más de un paciente. Resultados: El coste anual/paciente con NTB-A supondría entre 265Euros y 2.120Euros con un ahorro entre el 10% y 55% según la NTB-A seleccionada. DC y EBA presentarían el mayor coste/paciente. Botox(R) generaría un menor coste en EBA (di/dm) y DC(di) y en blefarospasmo y EPCI (di/dm/dmax). Dysport(R) tiene el menor coste en DC (dmax) y EBA (dmax) y Xeomin® en DC(dm). El coste anual por población según prevalencia supone entre 368.392 Euros y 13.958.836 Euros según indicación, dosis y NTB-A seleccionada. Conclusiones: Una selección adecuada de las presentaciones de NTB-A para cada indicación permitiría generar importantes ahorros para el Sistema Nacional de Salud. Botox(R) conseguiría menores costes anuales/paciente frente al resto de NTB-A en 9 de los 12 escenarios considerados

Objective: To estimate treatment costs of blepharospasm, cervical dystonia (CD), upper limb spasticity (ULS) and spasticity in children with cerebral palsy (SCCP) with botulinum neurotoxin type A (BoNT-A) in Spain. Method: Annual BoNT-A treatment costs were calculated (2013 ex-factory price (Euros) applying RDL 8/2010 and RDL 9/2011 deductions), based on initial dose (id), average dose (ad) and maximum dose (md) according to Summary of Product Characteristics of Botox® (100U/50U), Dysport® (500U) and Xeomin® (100U) and considering the use of complete vials. In addition, annual treatment costs were calculated considering the use of vials in more than one patient and also patient population annual treatment costs based on diseases’ prevalence. Results: Annual BoNT-A treatment costs per patient were estimated at between Euros265 and Euros2,120 with savings from 10% to 55% according to the selected BoNT-A. CD and ULS treatment provided the greatest cost per patient. Botox® provided greater savings in ULS (id/ad), CD(id), and in blepharospasm and SCCP (id/ad/md). Dysport® treatment was less costly in CD (md) and ULS (md), while Xeomin® was in CD(ad). Based on the estimated treated population in Spain, the annual treatment costs ranged from Euros368,392 to Euros13,958,836 depending on indication, dose and BoNT-A considered. Conclusions: The appropriate BoNT-A choice would lead to considerable savings for the National Health System. Botox® would generate lower costs per patient than other BoNT-A products in 9 out of 12 scenarios considered (AU)

Nonlinear dynamics induced by burst amplification in optically gain-stabilized erbium-doped amplifiers.

Optical burst amplification in a gain-stabilized amplifier may generate complex gain dynamics with nonlinear behavior. This phenomenon is thoroughly investigated by using a theoretical model and dedicated experiments. Design guidelines for optimized devices avoiding optical burst transmission impairments are proposed.

Trocar site hernia after laparoscopic ventral hernia repair.

BACKGROUND: The incidence of trocar site hernia (TSH) after laparoscopic ventral hernia repair (LVHR) is reported to be low. The present study investigates the associated risk factors, with a view to preventing this complication. METHODS: A retrospective study was made of the incidence of TSH in a personal series of LVHR, recording anthropometric and clinical data on the patients. Risk factors were assessed by bivariate and multivariate analyses. The patients were subjected to clinical and telephone follow-up. RESULTS: In a series of 27 LVHR, the incidence of TSH was 22% (6 patients). The use of meshes larger than 10 x 15 cm for LVHR was the only TSH risk factor to reach statistical significance. Female gender and diabetes showed a higher incidence in the TSH group. CONCLUSIONS: The use of large meshes may be a risk factor for TSH. We believe this to be due to dilatation of the trocar orifice during introduction of the mesh, and also to postoperative retraction of the mesh.

Respuesta del Dr. J. P. Aracil Kessler al comentario del Dr. A. Tapia sobre el artículo «Lifting frontal apoyado en malla de polipropileno» / No disponible

No disponible

Influencia del nivel educativo, la edad y la experiencia previa sobre los cuidados del niño con fiebre / Influence of level of education, age and prior experience on the management of a child with fever

La formación sanitaria de la población en un tema tan frecuente como el síndrome febril en la infancia es deficiente, en líneas generales, y motiva urgencias innecesarias, incrementa el gasto farmacéutico y tiene consecuencias negativas para la salud del niño (procedimientos erróneos y yatrogenia). El nivel educativo es un factor trascendente, pero un nivel educativo elevado no siempre lleva aparejado un grado de educación sanitaria suficiente. Los cuidadores menores de 20 años y mayores de 50 años, en general, destacan por su menor preparación en los cuidados del niño con fiebre. La experiencia de hijos anteriores aporta mejores conocimientos para el cuidado del niño, pero incrementa la automedicación con antibióticos (AU)

Estudio de conocimientos y actitudes de la población general ante un niño con fiebre / Study of the knowledge and attitudes of the general population concerning the management of a child with fever

Para conocer la necesidad de educación para la salud, se ha centrado la atención en una situación habitual: la fiebre. El estudio recoge 900 encuestas sobre conocimientos básicos y conducta ante un niño febril, aplicadas a personas al cuidado de niños en el momento de la realización. Las respuestas obtenidas confirman errores frecuentes en todos los apartados. La instrucción a los niños, las madres y los cuidadores se muestra esencial para reducir la urgencia innecesaria y la iatrogenia. Los cursos de puericultura dirigidos a este tipo de población deberían adquirir una mayor relevancia, incluyendo la educación general para la salud en las escuelas, a las madres potenciales y reales y, en general, al personal encargado del cuidado del niño (AU)

For the purpose of determining health education needs, we focused on a common complaint: fever. The study is based on 900 surveys dealing with basic knowledge and behavior in the event of fever in a child, distributed among caregivers working with children at the time it was carried out. This survey confirms the existence of common errors with respect to fever, antipyretic drugs and physical antipyretic measures. Education for children, mothers and caregivers is shown to be essential to reduce unnecessary emergencies and drug side effects. Greater emphasis should be placed on child care courses, including general education on health care offered in schools, to present and future mothers and, in general, to all caregivers dealing with children (AU)

Enzymatic esterification of an acid with an epoxide using an immobilized lipase from Mucor miehei as catalyst: optimization of the yield and isomeric excess of ester by statistical analysis.

We have developed the methodology for the esterification of an acid with an epoxide using 2-chlorobutyric acid and 1,2-epoxy-5-hexene catalysed by a Mucor miehei-immobilized lipase. Thus, this methodology could be applied to obtain 2-chloroesters. A factorial design of experiments and a central composite design have been used to optimise the synthesis of these esters. The variables chosen were temperature and initial catalyst concentration, while the responses were yield and isomeric excess of the ester. According to this study, temperature was the most important factor, having a positive influence on the yield and a small negative influence on the isomeric excess of the ester. The yield and isomeric excess of the ester show a greater dependence on temperature compared to the catalyst concentration. Although the effect of the catalyst concentration on both responses is smaller than the temperature effect, the higher selectivity presented by the biocatalyst towards the studied ester considerably decreased the final product distribution.

[Management of myocardial infarction in Spain (1995-99). Data from the registry of the Ischaemic Heart Disease Working Group (RISCI) of the Spanish Society of Cardiology]. / Manejo del infarto de miiocardio en España (1995-99). Datos del registro de infartos de la sección de cardiopatía Isquémica y unidades coronarias (RISCI) de la Sociedad Española de Cardiología.

INTRODUCTION AND OBJECTIVES: Limited information is available on how patients with myocardial infarction are treated in Spain. In order to make up for this deficiency, in October 1994, the Ischaemic Heart Disease Working Group of the Spanish Society of Cardiology initiated a myocardial infarction registry, which is currently active. METHODS: Patients are recruited from hospitals with intensive coronary care facilities. Demographic characteristics coronary risk factors and previous conditions are collected, as well as clinical events, and diagnostic and therapeutic procedures performed during the stay in the coronary care unit. RESULTS: From 1995 to 1999, 28,357 patients were registered. During this period the mean age increased slightly (from 64.4 +/- 12.2 to 65.2 +/- 12.7; p < 0.001), although the male proportion remained stable (from 76.7% to 77.1%). The median "onset of symptoms-hospital arrival for 1st emergency" time fell from 135 min to 120 min, and the median "onset of symptoms-needle" time from 180 to 175 (NS). The use of thrombolytic therapy did not change (from 42.4 to 43.9%), but the use of aspirin (from 87.4 to 91.7%), beta-blockers (from 32.7 to 39.6%) and angiotensin-converting inhibitors (from 27.9 to 34.8%) increased significantly (p < 0.001). The Swan-Ganz catheter and the intra-aortic balloon counterpulsation were rarely placed during the five years (4.2% and 1.2% respectively in 1999). Both early mortality (11.4 to 9.3%) and the median duration of intensive coronary care stay declined, in these 5 years. CONCLUSIONS: In Spain, during the 1995-1999 period, the use of aspirin, beta-blockers, and angiotensin-converting inhibitors increased significantly during the acute phase of infarction in the coronary care unit. However, both the usage of thrombolytic therapy and the delay between the onset of symptoms and therapy initiation remained unchanged. At the same time, the length of stay in the coronary care unit and early mortality declined, although the clinical profile of the patients did not improve.

Measures to reduce HIV infection have not been successful to reduce the prevalence of HCV in intravenous drug users.

The objective of the study was to determine whether measures taken to prevent human immunodeficiency virus (HIV) infection also lead to a reduction in the prevalence of hepatitis C virus (HCV) infection among intravenous drug users (IDU). Antibodies to HCV, HIV and hepatitis B virus (HBV) were determined in IDU who voluntarily attended AIDS prevention and information centres for the first time between 1990 and 1996. Of the 5473 IDU studied, determination of HCV was done in 3238 cases. The prevalence of antibodies to HCV was 85%. During the first period studied (1990-1992), the prevalence of antibodies to HCV was 84.5%, during the second (1993-1994) 84.1% and during the third (1995-1996) 87%; in the case of HBV the prevalence during the three periods was 74.5, 67.6 and 66.8% respectively, and for HIV it was 41.9, 38.8 and 36.6% respectively (RR: 0.72; 95% confidence interval (CI): 0.65-0.81). Among drug users addicted for less than 2 years, the trend of the prevalence of antibodies to HCV and HBV remained constant, while the prevalence of HIV infection decreased (RR: 0.61; 95% CI: 0.42-0.89). Measures to prevent transmission of HIV in drug users do not lead to a reduction in the prevalence of HCV infection. Further study is necessary to obtain a better understanding of how HCV is transmitted among drug users in order to apply measures which are effective in preventing HCV infection.

Kinetic modelling of the synthesis of 2-hydroxy-5-hexenyl 2-chlorobutyrate ester by an immobilised lipase.

An esterification process was developed for the direct synthesis of 2-hydroxy-5-hexenyl 2-chlorobutyrate ester from 2-chlorobutyric acid by using the epoxide 1,2-epoxy-5-hexene and Mucor miehei immobilised lipase as the biocatalyst in a batch reactor. The effect of temperature, catalyst concentration, and substrate and product concentration has been studied. An ordered Bi Uni enzymatic mechanism with competitive inhibition by the epoxide and acid has been proposed. The corresponding kinetic parameters were calculated by non-linear regression. Activation energy shows a value of 8.04kcal/mol. The thermodynamic parameters of the process, enthalpy and entropy, were 15.4kcal/mol and 45cal/mol, respectively.

[The short-term effects of air pollution on mortality. The results of the EMECAM project in the city of Valencia, 1994-96. Estudio Multcéntrico Español sobre la Relación entre la Contaminación Atmosférica y la Mortalidad]. / Efectos a corto plazo de la contaminación atmosférica sobre la mortalidad. Resultados del proyecto EMECAM en la ciudad de Valencia, 1994-96.

BACKGROUND: To determine the short-term impact of air pollution on mortality in the city of Valencia throughout the 1994-1996 period by employing the analysis method of the Spanish multicenter study with regard to the relationship between air pollution and the mortality (EMECAM Project). METHODS: The daily levels of black smoke, sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO) and ozone (O3) were obtained from the Valencia air pollution monitoring network. The death rate indicators analyzed were the daily number of death due to all causes, except the external ones, the deaths of those over age 70, and the deaths resulting from respiratory and cardiovascular diseases. Following the methods of the EMECAM Project, autoregressive Poison regression models were built up, controlling the different confounding factors (seasonality, trend, calendar, weather variables and flu impact). RESULTS: For total mortality except the external ones, a significant impact of black smoke (RR 10 micrograms/m3: 1.013; CI95% 1.003 to 1.023) and for CO 24 la (RR 1 mg/m3: 1.024; CI95% 1.003 to 1.046) was found. For the mortality of those individuals over 70, the estimated impact was somewhat greater than for black smoke (RR 10 micrograms/m3: 1.017; CI95% 1.005-1.029), as well as for CO2 1 h (RR 10 micrograms/m3: 1.007; CI95% 1.001-1.013). No significant relationship was found with the mortality due to respiratory or cardiovascular diseases for the entire period. CONCLUSIONS: The current levels of pollution in the city of Valencia show a significant impact on daily mortality. These findings are consistent with the previous research and are coherent with those obtained on analyzing the relationship between air pollution and morbidity indicators.

[The users of centers for AIDS information and prevention in the Comunidad Valenciana, Spain: a study based on cluster analysis]. / Usuarios de centros de información y prevención de SIDA en la Comunidad Valenciana: un estudio basado en el análisis de conglomerados.

OBJECTIVE: To measure the usefulness of multiple correspondence analysis (MCA) and cluster analysis applied to the epidemiological research of HIV infection. The specific are to explore the relationships between the different variables that characterize the users of the AIDS Information and Prevention Center (CIPS) and to identify clusters of characteristics which in terms of the attendance to these centers, could be considered similar. METHODS: The clinical history the CIPS in the Valencian region in Spain was used as data source. The target population target were intravenous drug users (IDUSs) attending these centers between 1987 and 1994 (n = 6211). Information about socio-demographic and HIV type I infection-related variables (drug use and sexual behaviour) was collected by means of a semistructured questionnaire. A MCA was carried out to obtain a group of quantitative factors that were used in a cluster analysis. RESULTS: A 44.8% HIV type I prevalence was found. Five factors were detected by MCA that explain 51.14% of the total variability, of which sex, age and the usual sexual partner were the variables best explained. Cluster analysis allowed to describe 5 different subgroups of CIPS users according to their socio-demographics characteristics, risk behaviours and serologic status. It is necessary to highlight the categories 1 and 2, which collect the serologic status and the most relevant characteristics of HIV infection. Category I contains users with a negative serology and characterized by being mainly single adolescent men, with a low educational level; they stated that they have no steady sexual partner, do not share syringes and have been intravenous drug users between 3 and 10 years. They mainly come from the city of Alicante. Category 2 contains mainly people that are HIV positive and older. They also share syringes and have been intravenous drug users for a longer time; they have a higher education level and most of them come from the city of Valencia. CONCLUSIONS: The proposed method of analysis was able to characterise the CIPS users, identifying those socio-demographic variables and risk behaviours that are more related to the serologic status. The applicability of these techniques to epidemiologic studies of HIV type I infection is discussed.

Human immunodeficiency virus (HIV) infection in parenteral drug users: evolution of the epidemic over 10 years. Valencian Epidemiology and Prevention of HIV Disease Study Group.

BACKGROUND: Evaluation of acquired immunodeficiency syndrome (AIDS) prevention strategies requires an on-going follow up of the frequency of human immunodeficiency virus (HIV-1) infection. The aim of this study was to examine the trends in prevalence and incidence of HIV-1 infection among injecting drug users (IDU) during the period 1987-1996. METHODS: Transversal and cohort studies were designed which included a consecutive sample of 7132 IDU who attended three AIDS Prevention and Information Centres in the Region of Valencia (Spain) and voluntarily asked to be tested for HIV antibodies. The prevalence was estimated for each year based on the serological status of HIV-1 when the patient first visited the centre. The annual incidence rates were calculated based on the seronegative patients in which a new determination of HIV-1 was done. In order to control the possible effects on the estimations of age, sex and duration of addiction of the people studied, Poisson and logistic regression models were adjusted. RESULTS: Prevalence and incidence rates of HIV-1 infection showed parallel trends over time. The overall prevalence found was 43.6% (95% confidence intervals [CI]: 42.4-44.7%). Of the 4023 seronegative individuals, 1746 were followed up over the whole of the study period. The incidence rate observed was 6.85 x 100 persons/year (95% CI : 6.04-7.66). The prevalence figures show a decrease, which is most marked from 1990 onwards and then they tend to stabilize over the past few years. The incidence rates increase slightly up to 1991 (9.8 x 100 persons/year), and then begin to decrease. CONCLUSION: Trends of prevalence of HIV-1 infection approximate trends of subjacent incidence rate. Despite decrease in HIV-1 infection frequency observed over 10 years, both the prevalence and incidence figures continue to be high in absolute terms. It is necessary to intensify and adapt preventive measures to each subgroup at risk of infection and in the case of heterosexual transmission ensure that the failure observed in the case of IDU is not repeated.

Extensor apparatus reconstruction with Leeds-Keio ligament in total knee arthroplasty.

The outcome of reconstruction of patellar tendon rupture in total knee arthroplasty has not been particularly good. Five cases of extensor mechanism rupture in total knee arthroplasty are presented. The surgical technique consisted of suture of the extensor apparatus augmented by a Leeds-Keio ligament. Active extension of -10 degrees was achieved by all the patients with flexion of 90 degrees or more. One superficial infection developed, which required antibiotic treatment. In the course of time, the reconstruction elongated less than 1 cm without significantly affecting function. Although the numbers are small and the complications significant, the final results of this technique have been reasonable. The technique permits early weight bearing and immediate mobilization, which enables an adequate range of motion to be achieved.