[Translated article] Wound closure after knee and hip replacement (TKA and THA): Survey results on the clinical practice in Spain.

BACKGROUND AND OBJECTIVE: In orthopaedic surgery, it is clear that an optimal standardised closure technique has not yet been developed. Locally, there are no objective data describing the standard surgical practice in wound closure. The aim of this study is to analyse the clinical practice of surgical wound closure in orthopaedic surgery by means of a survey of a representative local sample and thus obtain information on the context of closure in Spain. MATERIAL AND METHOD: An ad hoc group of specialists in orthopaedic surgery and traumatology was formed. The group of experts, after analyzing the literature, developed a questionnaire of 32 closed multiple-choice questions divided into the following blocks: hemostasis, surgical wound closure (deep, superficial, and cutaneous), and dressings. RESULTS: A total of 471 surgeons responded to the survey completely and with sufficient information to perform the descriptive analysis. 79% believe that ATX can influence the decrease in surgical site infection rate. 96% believe that the type of deep closure at the level of the arthrotomy could influence outcomes and complications after hip and/or knee replacements. 85% believe that the type of shallow closure at the subcutaneous level may influence outcomes and complications after hip and/or knee replacement. 64% of surgeons use single-use incisional negative pressure therapy for the treatment of surgical wound complications (seroma, prolonged drainage, dehiscence). CONCLUSIONS: There is a high level of variability in wound closure in our setting and a low level of training on the subject. The authors recommend that the different scientific societies invest resources to improve training in this field and reduce the percentage of surgeons who are considered inadequately trained, as well as adapting closure techniques to those considered gold standard according to the evidence.

Wound closure after knee and hip replacement (TKA and THA): Survey results on the clinical practice in Spain. / Cierre de herida en cirugía protésica de rodilla y cadera (PTR y PTC): Resultados de una encuesta sobre la práctica clínica en España.

BACKGROUND AND OBJECTIVE: In orthopedic surgery, it is clear that an optimal standardized closure technique has not yet been developed. Locally, there are no objective data describing the standard surgical practice in wound closure. The aim of this study is to analyze the clinical practice of surgical wound closure in orthopedic surgery by means of a survey of a representative local sample and thus obtain information on the context of closure in Spain. METHOD: an ad hoc group of specialists in orthopedic surgery and traumatology was formed. The group of experts, after analyzing the literature, developed a questionnaire of 32 closed multiple-choice questions divided into the following blocks: hemostasis, surgical wound closure (deep, superficial, and cutaneous), and dressings. RESULTS: A total of 471 surgeons responded to the survey completely and with sufficient information to perform the descriptive analysis. 79% believe that ATX can influence the decrease in surgical site infection rate. 96% believe that the type of deep closure at the level of the arthrotomy could influence outcomes and complications after hip and/or knee replacements. 85% believe that the type of shallow closure at the subcutaneous level may influence outcomes and complications after hip and/or knee replacement. 64% of surgeons use single-use incisional negative pressure therapy for the treatment of surgical wound complications (seroma, prolonged drainage, dehiscence). CONCLUSIONS: There is a high level of variability in wound closure in our setting and a low level of training on the subject. The authors recommend that the different scientific societies invest resources to improve training in this field and reduce the percentage of surgeons who are considered inadequately trained, as well as adapting closure techniques to those considered gold standard according to the evidence.

[Translated article] Overview of systematic reviews of risk factors for prosthetic joint infection.

BACKGROUND: Prosthetic joint infection is one of the most serious complications in orthopedics. Prognostic systematic reviews (SRs) detecting and assessing factors related to prosthetic joint infection, allow better prediction of risk and implementation of preventive measures. Although prognostic SRs are increasingly frequent, their methodological field presents some knowledge gaps. PURPOSE: To carry out an overview of SR assessing risk factors for prosthetic joint infection, describing and synthesizing their evidence. Secondarily, to assess the risk of bias and methodological quality. MATERIAL AND METHODS: We conducted a bibliographic search in 4 databases (May 2021) to identify prognostic SR evaluating any risk factor for prosthetic joint infection. We evaluated risk of bias with the ROBIS tool, and methodological quality with a modified AMSTAR-2 tool. We computed the overlap degree study between included SR. RESULTS: Twenty-three SRs were included, studying 15 factors for prosthetic joint infection, of which, 13 had significant association. The most frequently studied risk factors were obesity, intra-articular corticosteroids, smoking and uncontrolled diabetes. Overlapping between SR was high for obesity and very high for intra-articular corticoid injection, smoking and uncontrolled diabetes. Risk of bias was considered low in 8 SRs (34.7%). The modified AMSTAR-2 tool showed important methodological gaps. CONCLUSIONS: Identification of procedural-modifiable factors, such as intra-articular corticoids use, can give patients better results. Overlapping between SR was very high, meaning that some SRs are redundant. The evidence on risk factors for prosthetic joint infection is weak due to high risk of bias and limited methodological quality.

Overview of systematic reviews of risk factors for prosthetic joint infection. / Revisión de revisiones sistemáticas de factores pronóstico para infección protésica.

BACKGROUND: Prosthetic joint infection is one of the most serious complications in orthopedics. Prognostic systematic reviews (SR) detecting and assessing factors related to prosthetic joint infection, allow better prediction of risk and implementation of preventive measures. Although prognostic SR are increasingly frequent, their methodological field presents some knowledge gaps. PURPOSE: To carry out an overview of SR assessing risk factors for prosthetic joint infection, describing and synthesizing their evidence. Secondarily, to assess the risk of bias and methodological quality. MATERIAL AND METHODS: We conducted a bibliographic search in 4databases (May 2021) to identify prognostic SR evaluating any risk factor for prosthetic joint infection. We evaluated risk of bias with the ROBIS tool, and methodological quality with a modified AMSTAR-2 tool. We computed the overlap degree study between included SR. RESULTS: Twenty-three SR were included, studying 15 factors for prosthetic joint infection, of which, 13 had significant association. The most frequently studied risk factors were obesity, intra-articular corticosteroids, smoking and uncontrolled diabetes. Overlapping between SR was high for obesity and very high for intra-articular corticoid injection, smoking and uncontrolled diabetes. Risk of bias was considered low in 8SRs (34.7%). The modified AMSTAR-2 tool showed important methodological gaps. CONCLUSIONS: Identification of procedural-modifiable factors, such as intra-articular corticoids use, can give patients better results. Overlapping between SR was very high, meaning that some SR are redundant. The evidence on risk factors for prosthetic joint infection is weak due to high risk of bias and limited methodological quality.

[Translated article] Current situation of robotics in knee prosthetic surgery: A technology that has come to stay?

Robotic surgery is a surgical technique that is on the rise. The goal of robotic-assisted total knee arthroplasty (RA-TKA) is to provide the surgeon with a tool to accurately execute bone cuts according to previous surgical planning to restore knee kinematics and balance of soft tissue, being able to precisely apply the type of alignment that we choose. In addition, RA-TKA is a very useful tool for training. Within the limitations, there is the learning curve, the need for specific equipment, the high cost of the devices, the increase in radiation in some systems and that each robot is linked to a specific type of implant. Current studies show, with RA-TKA, variations in the alignment of the mechanical axis are reduced, postoperative pain is improved and earlier discharge is facilitated. On the other hand, there are no differences in terms of range of motion, alignment, gap balance, complications, surgical time or functional results.

Current situation of robotics in knee prosthetic surgery, a technology that has come to stay? / Situación actual de la robótica en cirugía protésica de rodilla, ¿una tecnología que ha venido para quedarse?

Robotic surgery is a surgical technique that is on the rise. The goal of robotic-assisted total knee arthroplasty (RA-TKA) is to provide the surgeon with a tool to accurately execute bone cuts according to previous surgical planning to restore knee kinematics and balance of soft tissue, being able to precisely apply the type of alignment that we choose. In addition, RA-TKA is a very useful tool for training. Within the limitations, there is the learning curve, the need for specific equipment, the high cost of the devices, the increase in radiation in some systems and that each robot is linked to a specific type of implant. Current studies show, with RA-TKA, variations in the alignment of the mechanical axis are reduced, postoperative pain is improved and earlier discharge is facilitated. On the other hand, there are no differences in terms of range of motion, alignment, gap balance, complications, surgical time or functional results.

Spray-driven halide exchange in solid-state CsPbX3 nanocrystal films.

CsPbI3 perovskite nanocrystals (NCs) are promising building blocks for photovoltaics and optoelectronics. However, they exhibit an essential drawback in the form of phase stability: α-phase, with a ∼1.80 eV bandgap, can easily experience a phase transition to a non-radiative orthorhombic δ-phase in an ambient environment. This leads to the need to carry out the CsPbI3-based device fabrication in an inert atmosphere, which is technologically inconvenient and expensive. One of the most successful approaches proposed to overcome this problem is synthesizing mixed halide CsPbBr3-xIx NCs to improve the stability of the α-phase perovskite structure. However, the formation of high-quality thin films of CsPbBr3-xIx NCs with high PLQY is challenging owing to the degradation of their optical properties after deposition on a substrate. This work presents spray coating to carry out a solid-state anion exchange in CsPbBr3 NCs thin films at ambient conditions with low-demanding reaction conditions. This constitutes a novel open-air and annealing-free technology to manufacture CsPbBr3-xIx NC thin films with high optical quality and record high photoluminescence quantum yields (PLQY) based on spray-driven halide (Br- to I-) anion exchange in a solid-state phase. Besides, tunable emission wavelengths between 520 and 670 nm can be obtained from CsPbBr3-xIx NC films using accurate tuning volumes of HI solution sprayed over the initial surface of CsPbBr3 film to provide the halide exchange. The optical quality of the halide-exchanged PNCs films remains practically identical to that of initial Br-containing layers, with a remarkable PLQY enhancement after anion exchange, from ∼61% for CsPbBr3 thin films emitting at 520 nm to ∼84% for mixed halide CsPbBr3-xIx film emitting at 640 nm. The huge potential of the system is confirmed by demonstrating a low-threshold amplified spontaneous emission.

Perioperative medicine role in painful knee prosthesis prevention.

Total knee arthroplasty is one of the most frequently performed orthopaedic surgeries. However, up to 20% of patients develop persistent postoperative pain. Persistent postoperative pain may be an extension of acute postoperative pain, but can also occur after more than 3 months without symptoms. Risk factors associated with persistent postoperative pain after arthroplasty have now been characterised within the patient's perioperative context (preoperative, intraoperative and postoperative), and can be grouped under genetic, demographic, clinical, surgical, analgesic, inflammatory and psychological factors. Identification and prevention of persistent postoperative pain through a multimodal and biopsychosocial approach is essential in the context of perioperative medicine, and has been shown to prevent or ameliorate postoperative pain.

PREVENCOT project: Do we follow international guidelines to prevent surgical site infection in orthopedic elective surgery? / Proyecto PREVENCOT: ¿Seguimos las recomendaciones internacionales para la prevención de la infección del sitio quirúrgico en cirugía ortopédica programada?

BACKGROUND AND OBJECTIVE: Prevention of postoperative surgical site infections is indeed feasible. The aim of this work is to analyses adherence to international guidelines for the prevention of infections in elective orthopedic prosthetic surgery by means of a survey of a representative sample of Spanish orthopedic surgeons, with the purpose to establish general recommendations. MATERIAL AND METHOD: A population survey was conducted in online format consisting of 78 questions to analyze the usual clinical practice of Spanish orthopedic surgeons in the face of periprosthetic infections of the hip and knee, and their adherence to international guidelines. RESULTS: The results of the survey (n=138) show in clinical practice of Spanish orthopedic surgeons a high adherence to most of the international recommendations. CONCLUSIONS: The integration high adherence of individual clinical practice with the best available scientific evidence based on the recommendations of international guidelines is the best way to adequately manage the prevention of periprosthetic infection in elective surgery.

Usefulness of histology for predicting infection at the time of hip and knee revision in patients with rheumatoid arthritis.

INTRODUCTION: It remains unclear whether rheumatoid arthritis might be a cause of false positive of the histology for the diagnosis of prosthetic joint infection. Our aim was to evaluate the usefulness of the histology for the diagnosis of infection during hip and knee prosthesis revision in patients with rheumatoid arthritis. MATERIALS AND METHODS: All patients with the diagnosis of rheumatoid arthritis (RA) undergoing hip or knee revision surgery (total or partial) were retrospectively reviewed. Positive histology was considered when ≥ 5 neutrophils per high-power field (400×) were found in at least five separate microscopic fields. Patients who presented ≥ 2 positive cultures for the same microorganism or the presence of fistula were considered as "true positives". RESULTS: Thirty-two hip (n = 12) and knee (n = 20) revision procedures were performed. Sensitivity, specificity, positive and negative predictive value of the histology were 50%, 78.6%, 25% and 91.7%, respectively. Six out of the eight patients presenting with positive histology had negative cultures (75.0% of false positives). CONCLUSIONS: Our results suggest that, in the context of RA, negative histological results have a very high negative predictive value. RA poses false positive histology results for the diagnosis of infection during hip and knee revision when conventional cultures are used for diagnosis of infection.

Perioperative medicine role in painful knee prosthesis prevention. / Papel de la medicina perioperatoria en la prevención de la prótesis de rodilla dolorosa.

Total knee arthroplasty is one of the most frequently performed orthopaedic surgeries. However, up to 20% of patients develop persistent postoperative pain. Persistent postoperative pain may be an extension of acute postoperative pain, but can also occur after more than 3 months without symptoms. Risk factors associated with persistent postoperative pain after arthroplasty have now been characterised within the patient's perioperative context (preoperative, intraoperative and postoperative), and can be grouped under genetic, demographic, clinical, surgical, analgesic, inflammatory and psychological factors. Identification and prevention of persistent postoperative pain through a multimodal and biopsychosocial approach is essential in the context of perioperative medicine, and has been shown to prevent or ameliorate postoperative pain.

Arthrotomy debridement of arthrostic septic arthritis of the knee is more effective than arthroscopic debridement and delays the need for prosthesis despite progression. / El desbridamiento por artrotomía de la artritis séptica de rodilla artrósica es más eficaz que el artroscópico y retrasa la necesidad de prótesis a pesar de la progresión de la artrosis.

BACKGROUND AND OBJECTIVE: 40%-50% of this septic arthritis occurs in the knee, despite rapid medical surgical treatment, 24%-50% will have a poor clinical outcome. It is not clear which debridement technique, by arthrotomy or arthroscopy, is more effective in controlling infection, or whether or not previous osteoarthritis worsens the outcome. The objective of this study on septic arthritis of the osteoarthritic knee was to analyse which surgical debridement technique, arthroscopy or arthrotomy, is more effective, the clinical and radiographic outcomes of the patients, and how many go on to require a TKR after the infection has healed. MATERIAL AND METHODS: A retrospective study was performed in 27 patients with native septic arthritis of the knee. Eighteen were men and the mean age was 64.8 years (30-89years). Fifteen patients were debrided by arthrotomy and 12 by arthroscopy. The effectiveness of debridement in controlling infection, the radiographic progression of the osteoarthritis on the Ahlbäch scale, the need for subsequent replacement, and pain and functional status were analysed using the VAS and WOMAC scales at 52.8±11.2-month follow-up. RESULTS: The infection was controlled in 93% and 92% of the patients, 13% and 42% required 2 or more surgeries for infection control, 18% and 44.4% showed progression of arthritis in the arthrotomy and arthroscopy groups, respectively. One patient in each group required a knee replacement. The VAS score was superior in the arthrotomy group and there were no differences in WOMAC score. CONCLUSION: Debridement by arthrotomy in the emergency department by non-sub-specialist knee surgeons is more effective than arthroscopic debridement in controlling septic arthritis of the knee. Surgical debridement of septic arthritis in knees with previous osteoarthritis enabled control of the infection with no pain despite the progression of the osteoarthritis.

Validity of the KLIC and CRIME80 scores in predicting failure in late acute infection treated by debridement and implant retention. / Validez de las escalas KLIC y CRIME80 en la predicción del fracaso en la infección aguda tardía tratada mediante desbridamiento y retención de implantes.

It is very important to treat prosthetic infections correctly in order to ensure a higher success rate. Debridement with implant retention (DAIR) is widely used in acute and late infections, however patients who fail after this surgery are known to have a higher risk of failure in subsequent surgeries. Therefore, it is important to find a scale that enables us to predict the risk of DAIR failure. Hence the KLIC and CRIME80 scores for acute and late acute infections, respectively. This study analysed the validity of both scores in acute late periprosthetic knee infections. We observed that the KLIC score has no predictive value for this type of infection, but the CRIME80 score does.

Enhanced Nonlinear Optical Coefficients of MAPbI3 Thin Films by Bismuth Doping.

The poor photostability under ambient conditions of hybrid halide perovskites has hindered their recently explored promising nonlinear optical properties. Here, we show how Bi3+ can partially substitute Pb2+ homogeneously in the commonly studied MAPbI3, improving both environmental stability and photostability under high laser irradiation. Bi content around 2 atom % produces thin films where the nonlinear refractive (n2) and absorptive coefficients (ß), which modify the refractive index (Δn) of the material with light fluence (I), increase up to factors of 4 and 3.5, respectively, compared to undoped MAPbI3. Higher doping inhibits the nonlinear parameters; however, the samples show higher fluence damage thresholds. Thus, these results provide a road map on how MAPbI3 can be engineered for practical cost-effective nonlinear applications by means of Bi doping, including optical limiting devices and multiple-harmonic generation into optoelectronics devices.

Structural characterization of bulk and nanoparticle lead halide perovskite thin films by (S)TEM techniques.

Lead halide (APbX3) perovskites, in polycrystalline thin films but also perovskite nanoparticles (NPs) has demonstrated excellent performance to implement a new generation of photovoltaic and photonic devices. The structural characterization of APbX3 thin films using (scanning) transmission electron microscopy ((S)TEM) techniques can provide valuable information that can be used to understand and model their optoelectronic performance and device properties. However, since APbX3 perovskites are soft materials, their characterization using (S)TEM is challenging. Here, we study and compare the structural properties of two different metal halide APbX3 perovskite thin films: bulk CH3NH3PbI3 prepared by spin-coating of the precursors in solution and CsPbBr3 colloidal NPs synthetized and deposited by doctor blading. Both specimen preparation methods and working conditions for analysis by (S)TEM are properly optimized. We show that CH3NH3PbI3 thin films grown by a one-step method are composed of independent grains with random orientations. The growth method results in the formation of tetragonal perovskite thin films with good adherence to an underlying TiO2 layer, which is characterized by a photoluminescence (PL) emission band centered at 775 nm. The perovskite thin films based on CsPbBr3 colloidal NPs, which are used as the building blocks of the film, are preserved by the deposition process, even if small gaps are observed between adjacent NPs. The crystal structure of CsPbBr3 NPs is cubic, which is beneficial for optical properties due to its optimal band gap. The absorption and PL spectra measured in both the thin film and the colloidal solution of CsPbBr3 NPs are very similar, indicating a good homogeneity of the thin films and the absence of aggregation of NPs. However, a particular care was required to avoid long electron irradiation times during our structural studies, even at a low voltage of 80 kV, as the material was observed to decompose through Pb segregation.

[Septic arthritis of the knee by Staphylococcus warneri]. / Artritis séptica de rodilla por Staphylococcus warneri.

Septic arthritis usually occurs as an acute joint process that can cause a rapid destruction of the cartilage, if the necessary therapeutic measures were not taken. Rarely, Staphylococcus warneri may be the cause of this pathology although due to its diagnostic difficulty we can make mistakes in its treatment. We present the case of a patient with septic arthritis of the knee by this germ and we intend to remark what are the diagnostic measures and recommendations to consider for this osteoarticular infection.

La artritis séptica suele presentarse como un proceso articular agudo que puede provocar una rápida destrucción del cartílago, si no se toman las medidas terapéuticas necesarias. De manera poco frecuente, el Staphylococcus warneri puede ser la causa de esta patología aunque por su dificultad diagnóstica podemos cometer errores en su tratamiento. Presentamos el caso de un paciente con artritis séptica de rodilla por este germen y pretendemos remarcar cuáles son las medidas diagnósticas y recomendaciones a tener en cuenta para esta infección osteoarticular.

Excitonic complexes in GaN/(Al,Ga)N quantum dots.

Here we report a theoretical investigation of excitonic complexes in polar GaN/(Al,Ga)N quantum dots (QDs). A sum rule between the binding energies of charged excitons is used to calculate the biexciton binding energy. The binding energies of excitonic complexes in GaN/AlN are shown to be strongly correlated to the QD size. Due to the large hole localization, the positively charged exciton energy is found to be always blueshifted compared to the exciton one. The negatively charged exciton and the biexciton energy can be blueshifted or redshifted according to the QD size. Increasing the size of GaN/AlN QDs makes the identification of charged excitons difficult, and the use of an Al0.5Ga0.5N barrier can be advantageous for clear identification. Our theoretical results for the binding energy of exciton complexes are also confronted with values deduced experimentally for InAs/GaAs QDs, confirming our theoretical prediction for charged excitonic complexes in GaN/(Al,Ga)N QDs. Finally, we realize that the trends of excitonic complexes in QDs are significantly related to competition between the local charge separation (whatever its origin) and the correlation effect. Following our findings, entangled photons pairs can be produced in QDs with careful control of their size in order to obtain zero exciton-biexciton energy separation.

Optical contrast of 2D InSe on SiO2/Si and transparent substrates using bandpass filters.

The particular optical and electronic properties recently reported for 2D InSe depict this 2D material as being very versatile for future electronic and optoelectronic devices with tunable and optimized functionalities. For its fundamental study and the development of practical applications, rapid and accurate identification methods of atomically thin InSe are essential. Here, we demonstrate an enhancement of the optical contrast between InSe nanosheets and the underlying SiO2/Si substrate by illuminating with a 40 nm wide bandpass filter centered at 500 nm. Moreover, we study the optical contrast of 2D InSe on transparent substrates. Our results suggest that a good optical contrast is achieved for transparent substrates with low real refractive indices such as LiF or a viscoelastic polydimethylsiloxane stamp. In this case, an optimum optical contrast would be achieved by using a bandpass filter centered at 450 nm. These results can be very useful for speeding up the continuously growing research on 2D InSe and its applications.

All-Optical Fiber Hanbury Brown &Twiss Interferometer to study 1300 nm single photon emission of a metamorphic InAs Quantum Dot.

New optical fiber based spectroscopic tools open the possibility to develop more robust and efficient characterization experiments. Spectral filtering and light reflection have been used to produce compact and versatile fiber based optical cavities and sensors. Moreover, these technologies would be also suitable to study N-photon correlations, where high collection efficiency and frequency tunability is desirable. We demonstrated single photon emission of a single quantum dot emitting at 1300 nm, using a Fiber Bragg Grating for wavelength filtering and InGaAs Avalanche Photodiodes operated in Geiger mode for single photon detection. As we do not observe any significant fine structure splitting for the neutral exciton transition within our spectral resolution (46 µeV), metamorphic QD single photon emission studied with our all-fiber Hanbury Brown &Twiss interferometer could lead to a more efficient analysis of entangled photon sources at telecom wavelength. This all-optical fiber scheme opens the door to new first and second order interferometers to study photon indistinguishability, entangled photon and photon cross correlation in the more interesting telecom wavelengths.

Polymer waveguide couplers based on metal nanoparticle-polymer nanocomposites.

In this work Au nanoparticles (AuNPs) are incorporated into poly(methyl methacrylate) (PMMA) waveguides to develop optical couplers that are compatible with planar organic polymer photonics. A method for growing AuNPs (of 10 to 100 nm in size) inside the commercially available Novolak resist is proposed with the intention of tuning the plasmon resonance and the absorption/scattering efficiencies inside the patterned structures. The refractive index of the MNP-Novolak nanocomposite (MNPs: noble metal nanoparticles) is carefully analysed both experimentally and numerically in order to find the appropriate fabrication conditions (filling factor and growth time) to optimize the scattering cross section at a desired wavelength. Then the nanocomposite is patterned inside a PMMA waveguide to exploit its scattering properties to couple and guide a normal incident laser light beam along the polymer. In this way, light coupling is experimentally demonstrated in a broad wavelength range (404-780 nm). Due to the elliptical shape of the MNPs the nanocomposite demonstrates a birefringence, which enhances the coupling to the TE mode up to efficiencies of around 1%.