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Two-dimensional (2D) transition metal dichalcogenides (TMDs) and perovskites hold substantial promise for various optoelectronic applications such as light emission, photodetection, and energy harvesting. However, each of these materials possesses certain limitations that can be overcome by synergistically combining them to form heterostructures, thereby unveiling intriguing optical properties. In this study, we present an uncomplicated technique for crafting a van der Waals (vdW) heterojunction comprising monolayer WS2 and a Ruddlesden-Popper (RP) perovskite, namely (TEA)2PbI4. By utilizing ultrafast transient absorption (TA) spectroscopy, we explored the charge carrier dynamics within the WS2/(TEA)2PbI4 heterostructure. Our findings uncover a type-II band alignment in the heterostructure, facilitating rapid (within 260 fs) hole transfer from WS2 to the perovskite and leading to the formation of interlayer excitons (IXs) with a much longer lifetime (728 ps). This strategic approach has the potential to contribute to the development of hybrid systems aimed at achieving high-performance optoelectronic devices.
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Tin (II) monosulfide (SnS) has attracted considerable attention in emerging photonics and optoelectronics because of high carrier mobility, large absorption coefficient, anisotropic linear and nonlinear optical properties, and long-time stability. In this Letter, we report third-order nonlinear absorption and refraction of SnS quantum dots (QDs). Under excitation with 800-nm femtosecond pulses, QDs exhibit saturable absorption (saturation intensity â¼ 47.69 GW/cm2) and positive refractive nonlinearity (nonlinear refraction coefficient â¼ 1.24 × 10-15 cm2/W). Nonetheless, we investigate charge carrier dynamics using femtosecond transient absorption spectroscopy and propose the presence of midgap defect states which not only dictate carrier dynamics but also give rise to nonlinear optical properties in SnS QDs.
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Despite several methods available for the treatment of solid wastes, the management of municipal solid waste is still a crucial and complex process. The available methods for waste treatment range from advanced to conventional techniques. The identification of a proper method for municipal solid waste management involves several techno-eco and environmental considerations. To solve the real-world problems of municipal waste management, the research proposed an integrated q-rung orthopair fuzzy number-based stepwise weight assessment ratio analysis-complex proportional assessment (SWARA-COPRAS) mathematical model to rank the waste treatment techniques. The research aimed to develop a systematic approach for a suitable selection of waste treatment methods. Ten (10) different alternatives for waste treatments were ranked against seven (07) different techno-eco and environmental criteria. The ambiguity in the decision was handled by the q-rung orthopair fuzzy numbers. The proposed integrated model has identified upcycling and recycling of waste having priority values of 100% and 99.9%, respectively, as the suitable practices for the successful management of generated solid wastes, whereas landfilling has obtained a minimum priority value of 66.782% and, therefore, is least preferable for waste management. The ranking of the alternatives followed the sequence as upcycling > recycling > pyrolysis > hydrolysis > biotechnological > core plasma pyrolysis > incineration > composting > gasification > landfilling. The comparison between the rankings of the proposed model with other techniques has revealed that the values of Spearman's rank correlation coefficient are in the range of 0.8545 to 0.9272; thereby, the robustness of the proposed model is verified. Sensitivity analysis for the criteria weight has showed that the ranking results are influenced significantly by the change in criteria weights and suggested that an accurate estimation of the criteria weight is decisive in determining the overall ranking of the alternative. The study has provided a framework for decision-making in the technology selection for solid waste management.
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Compostaje , Administración de Residuos , Residuos Sólidos/análisis , Administración de Residuos/métodos , Modelos Teóricos , TecnologíaRESUMEN
The present study aimed to investigate an outbreak of Theileria annulata (T. annulata) infection in an organized dairy cattle farm in Madhya Pradesh, India, using clinical and molecular techniques. Following the deaths of two crossbred cattle in March 2021, 43 blood samples were collected from infected and apparently healthy animals and examined by blood smear and polymerase chain reaction (PCR) techniques. The blood smear examination showed that 23.25% of samples were positive for Theileria organisms, while conventional PCR targeting the 18S ribosomal RNA (18S rRNA) and T. annulata merozoite surface antigen-1 (TAMS-1) genes revealed that 32.55% of samples were positive for T. annulata. PCR targeting cytochrome b (Cytb) gene showed 46.51% of samples were positive for T. annulata. Haematological analysis confirmed clinical signs of infection in affected animals, which were treated with buparvaquone @ 2.5 mg/kg body weight intramuscularly along with supportive medicine. Two 18S rRNA gene amplicons were sequenced and analysed in a phylogenetic tree and haplotype network with 54 Indian and 38 foreign sequences. The phylogenetic tree revealed two groups with a high posterior probability and bootstrap value, while the haplotype network revealed 35 haplotypes, with haplotype 1 (H1) being the most abundant and several single haplotypes clustering around it, indicating fast and widespread expansion. Genetic diversity indices and neutrality tests confirmed that the population was expanding. These studies highlight the significance of prompt and precise diagnosis and management of T. annulata outbreaks and provide insights into its evolutionary history and population dynamics of T. annulata in India, which could aid improving disease preventive and control strategies.
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Enfermedades de los Bovinos , Theileria annulata , Theileriosis , Bovinos , Animales , Theileriosis/epidemiología , Filogenia , Granjas , Theileria annulata/genética , ARN Ribosómico 18S/genética , India/epidemiología , Brotes de Enfermedades/veterinaria , Enfermedades de los Bovinos/epidemiologíaRESUMEN
The increasing demand for shelters, depleting natural resources, concern for plastic waste, and rising awareness for the environment have attracted the contemporary world towards the recycling of waste plastics for the development of an alternative and sustainable building construction material. The plastics suffer due to their poor strength which can be successfully overcome by the reinforcement of natural fibers. The work aimed to develop and investigate the properties of natural fiber-reinforced composites for structural applications such as floor tiles and pavements. The composites were developed by utilizing three different types of waste plastics, namely, low-density polyethylene, high-density polyethylene, and polypropylene with the reinforcement of coconut (cocos nucifera) and Tossa jute (corchorus olitorius) fibers. The evaluation of the density, water absorption, compressive strength, and flexural strength was performed. Moreover, three-body abrasive wear performance was investigated under the conditions of different loads and sliding speeds. The wear mechanism was explored by the morphological analyses of the fractured and worn-out surfaces. The composite HDPE80C20 showed a maximum density of 1.603 g/cm3 and minimum percentage of water absorption to 0.2022. Moreover, the composite attained a maximum compressive and flexural strength of 40.10 and 10.04 (MPa), respectively. The ranges for abrasive wear were found to be 0.002375-0.20015 (cm3) and 0.01987-0.39593 (cm3) under the considered conditions of loads and sliding speeds, respectively. The comparative analysis of the properties suggested the reinforcement of 20 wt% of jute fiber with 80 wt% of high-density polyethylene for the development of composites for structural applications. The study highlighted the potential of waste plastics and natural fibers as value-added products for building construction with relevancy from socio-eco and environmental points of view.
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Utilization of the excess energy of photoexcitation that is otherwise lost as thermal effects can improve the efficiency of next-generation light-harvesting devices. Multiple exciton generation (MEG) in semiconducting materials yields two or more excitons by absorbing a single high-energy photon, which can break the Shockley-Queisser limit for the conversion efficiency of photovoltaic devices. Recently, monolayer transition metal dichalcogenides (TMDs) have emerged as promising light-harvesting materials because of their high absorption coefficient. Here, we report efficient MEGs with low threshold energy and high (86%) efficiency in a van der Waals (vdW) layered material, MoS2. Through different experimental approaches, we demonstrate the signature of exciton multiplication and discuss the possible origin of decisive MEG in monolayer MoS2. Our results reveal that vdW-layered materials could be a potential candidate for developing mechanically flexible and highly efficient next-generation solar cells and photodetectors.
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The diverse nature of polymers with attractive properties has replaced the conventional materials with polymeric composites. The present study was sought to evaluate the wear performance of thermoplastic-based composites under the conditions of different loads and sliding speeds. In the present study, nine different composites were developed by using low-density polyethylene (LDPE), high-density polyethylene (HDPE) and polyethylene terephthalate (PET) with partial sand replacements i.e., 0, 30, 40, and 50 wt%. The abrasive wear was evaluated as per the ASTM G65 standard test for abrasive wear through a dry-sand rubber wheel apparatus under the applied loads of 34.335, 56.898, 68.719, 79.461 and 90.742 (N) and sliding speeds of 0.5388, 0.7184, 0.8980, 1.0776 and 1.4369 (m/s). The optimum density and compressive strength were obtained to be 2.0555 g/cm3 and 46.20 N/mm2, respectively for the composites HDPE60 and HDPE50 respectively. The minimum value of abrasive wear were found to 0.02498, 0.03430, 0.03095, 0.09020 and 0.03267 (cm3) under the considered loads of 34.335, 56.898, 68.719, 79.461 and 90.742 (N), respectively. Moreover, the composites LDPE50, LDPE100, LDPE100, LDPE50PET20 and LDPE60 showed a minimum abrasive wear of 0.03267, 0.05949, 0.05949, 0.03095 and 0.10292 at the sliding speeds of 0.5388, 0.7184, 0.8980, 1.0776 and 1.4369 (m/s), respectively. The wear response varied non-linearly with the conditions of loads and sliding speeds. Micro-cutting, plastic deformations, fiber peelings, etc. were included as the possible wear mechanism. The possible correlations between wear and mechanical properties, and throughout discussions for wear behaviors through the morphological analyses of the worn-out surfaces were provided.
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Plásticos , Arena , Dióxido de Silicio , Ensayo de Materiales , Polímeros , PolietilenoRESUMEN
Strict environmental concerns, depleting natural recourses, and rising demand for building construction materials have promoted scientific research toward alternative building materials. This research supports the idea of sustainability and a circular economy via the utilization of waste to produce value-added products. The research explored the potential of waste plastics and silica sand for developing thermoplastic composite as floor tiles. The samples were characterized by water absorption, compressive strength, flexural strength, and sliding wear. The morphological analysis of the sand-plastic interfaces was covered under the umbrella of this study. The maximum compressive and flexural strength were found to be 46.20 N/mm2 and 6.24 N/mm2, respectively, with the minimum water absorption and sliding wear rate of 0.039% and 0.143 × 10-8 kg/m, respectively. The study suggests the workability of the developed floor tiles in non-traffic areas of public places. Thus, the study provides a green building material through recycling waste plastics for sustainable development.
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Plásticos , Arena , Dióxido de Silicio , Reciclaje , AguaRESUMEN
Background: The present study was aimed to evaluate the efficacy of 1.2% Atorvastatin (ATV) with 1.2% Rosuvastatin (RSV) as local drug delivery for treatment of Chronic Periodontitis (CP). Materials and Methods: Forty patients were equally divided into two groups. Group A underwent scaling and root debridement and 1.2% ATV gel (1.2 mg/0.1 mL) was placed, whereas group B received scaling and root debridement and RSV (1.2 mg/0.1 ml) was placed. Results: The results showed that both the groups had improvement in all the recorded parameters, and the results obtained were statistically significant. When comparison was made between the groups, no significant difference was obtained between atorvastatin and rosuvastatin at baseline in all recorded parameters. However, after 6 months significant improvement was recorded in CAL (Clinical attachment level) and PD (Probing depth). The plaque index (PI) and gingival index (GI) score however showed improvement, but it did not attain the level of significance. Conclusion: The present study showed improvement in clinical parameters with the use of ATV and RSV gel when used in combination with scaling and root planing (SRP) in CP patients. Patients with RSV gel showed up significantly better than the ones in which ATV gel was placed.
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Periodontitis Crónica , Atorvastatina/uso terapéutico , Periodontitis Crónica/tratamiento farmacológico , Raspado Dental/métodos , Humanos , Aplanamiento de la Raíz/métodos , Rosuvastatina Cálcica/uso terapéutico , Resultado del TratamientoRESUMEN
The usage of waste for the development of sustainable building materials has received an increasing attention in socio-eco-environment spheres. The rice husk ash (RHA) produced during burning of rice husk and the ever-increasing plastic wastes are useless causing detrimental effects on the environment. This research supports the idea of sustainability and circular economy via utilization of waste to produce value-added products. This research explores the potential of waste plastics, RHA, and silica sand as thermoplastic composite materials. The different composite samples were prepared through waste plastics which includes low- and high-density polyethylene and polypropylene with incorporation of RHA and silica sand in proportions. The study investigates the effect of filler/polymer in 30/70, 20/80, and 10/90 (wt. %) on the workability of the developed composite materials. The workability of the composites was found to improve with filler reinforcement. The experimental results showed the maximum density of 1.676 g/cm3 and mechanical strength of 26.39, 4.89, and 3.25 MPa as compressive, flexural, and tensile strengths, respectively. The minimum percentage of water absorption was 0.052%. The wear tests resulted in a minimum abrasive and sliding wear rate of 0.03759 (cm3) and 0.00692 × 10-6 kg/m. The correlations between wear mechanisms and responses were morphologically analyzed. The developed composites verify the feasibility of RHA and plastics waste as a cost effective and environmentally competent product. The results and discussions provided a direction for the future research on sustainable polymeric composite materials.
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RF-discharge lamp is a key component in space- and ground-based compact and portable atomic clocks, such as rubidium atomic frequency standards (RAFSs). Precise thermal, structural design, and control of a rubidium (Rb) bulb is of crucial importance for long-term reliable operation of the onboard clocks. An important aspect is the potting material that is used to mount the Rb bulb. Potting material directly determines the thermal contact between liquid Rb pool inside glass bulb enclosure and the heating element, which is the only path to control the Rb bulb's temperature. Failure or degradation of thermal contact of the Rb bulb with its metallic base will lead to Rb clock degradation or failure. Considering this, we have successfully designed, simulated, implemented, characterized, and tested the use of indium metal as a replacement to epoxy for the Rb bulb bonding that can be implemented in future space Rb atomic clocks. Its thermal advantage over other routine space-qualified epoxies and flexibility for multiple bonding and unbonding mechanisms make it ideal for such applications. The usefulness of key properties of indium for various other space and ground applications is discussed.
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Aerosol behavior over the Himalayas plays an important role in the regional climate of South Asia. Previous studies at high-altitude observatories have provided evidence of the impact of long-range transport of pollutants from the Indo-Gangetic Plain (IGP). However, little information exists for the valley areas in the high Himalayas where significant local anthropogenic emissions can act as additional sources of short-living climate forcers and pollutants. The valley areas host most economic activities based on agriculture, forestry, and pilgrimage during every summer season. We report here first measurements at a valley site at ~2600 m a.s.l. on the trek to the Gangotri glacier (Gaumukh), in the Western Himalayas, where local infrastructures for atmospheric measurements are absent. The study comprised short-term measurement of aerosols, chemical characterization, and estimation of aerosol radiative forcing (ARF) during the winter and summer periods (2015-2016). The particulate matter mass concentrations were observed to be higher than the permissible limit during the summer campaigns. We obtained clear evidence of the impact of local anthropogenic sources: particulate nitrate is associated with coarse aerosol particles, the black carbon (BC) mass fraction appears undiluted with respect to measurements performed in the lower Himalayas, and in winter, both BC and sulfate concentrations in the valley site are well above the background levels reported from literature studies for mountain peaks. Finally, high concentrations of trace metals such as copper point to anthropogenic activities, including combustion and agriculture. While most studies in the Himalayas have addressed pollution in the high Himalayas in terms of transport from IGP, our study provides clear evidence that local sources cannot be overlooked over the high-altitude Himalayas. The estimated direct clear-sky ARF was estimated to be in the range of -0.1 to +1.6 W m-2, with significant heating in the atmosphere over the high-altitude Himalayan study site. These results indicate the need to establish systematic aerosol monitoring activities in the high Himalayan valleys.
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Contaminantes Atmosféricos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Altitud , Efectos Antropogénicos , Monitoreo del Ambiente , India , Estaciones del AñoRESUMEN
STUDY QUESTION: Is exclusive use of intragestational sac potassium chloride (KCl) and methotrexate (MTX) effective in the management of viable cesarean scar pregnancy (CSP)? SUMMARY ANSWER: Exclusive use of intragestational sac KCl and MTX was effective in the management of viable CSP. WHAT IS KNOWN ALREADY: Owing to a paucity of randomized studies on management of CSP, evidence-based management remains unclear. Intragestational sac KCl or MTX along with either systemic MTX or surgical intervention, such as uterine artery embolization or dilation and curettage, has proved to be effective in the management of CSP. Furthermore, there are limited data in the literature on the use of exclusive intragestational sac KCl and MTX for management of CSP and subsequent fecundity. STUDY DESIGN SIZE DURATION: A prospective cohort study was conducted from June 2017 to September 2019. We recruited nine CSP patients referred to our unit. There was no lost to follow-up noted. PARTICIPANTS/MATERIALS SETTING METHODS: Patients with an ultrasound diagnosis of CSP who fulfilled the inclusion criteria were recruited. The study was conducted in a tertiary care center. Clinical symptoms, pregnancy viability, gestational age and human chorionic gonadotrophin (HCG) values determined the management in each individual case. Accordingly, patients were grouped into the expectant management (Group I, n = 3) and intragestational sac KCl with MTX (Group II, n = 6) groups. Demographic details, clinical characteristics, ultrasound details at diagnosis, post-treatment HCG normalization time, menses resumption, mass resolution and subsequent fecundity were noted. Descriptive statistics were used for analyses. MAIN RESULTS AND THE ROLE OF CHANCE: Of the nine patients with CSP, six patients had viable CSP and required intervention. Out of these, four patients expressed a desire for future fertility. Mean gestational age at treatment among patients in Group II was 54.33 ± 7.51 days (range 46-65). Mean HCG value at the time of diagnosis was 84 110 ± 38 679.39 IU/l in Group II patients as compared with 2512 ± 709.36 in Group I. HCG had decreased by 92.7 ± 3.78% 2 weeks after intervention and normalized (<5 IU/l) by 53.5 ± 14.97 days. No major complications occurred and additional treatment was not required in these patients. Menstruation had resumed by 26 ± 6.6 days after treatment in Group II. On follow up, a small unresolved mass was present in two patients and the cesarean scar niche was visible in the remaining four patients. Out of the four patients desirous of future conception, three conceived naturally and one delivered a term baby via repeat lower segment cesarean section. LIMITATIONS REASONS FOR CAUTION: The main limitation of our study was small sample size. All the patients were asymptomatic at presentation and hence we cannot comment on use of this method in those presenting with active vaginal bleeding. WIDER IMPLICATIONS OF THE FINDINGS: Intragestational sac KCl plus MTX may be a highly effective approach for the management of viable CSP despite high initial HCG values. There seems to be no need for any further intervention. It can be considered as the first line minimally invasive treatment option in patients desirous of future fertility. Nevertheless, accumulation of further cases is required to validate this treatment modality. STUDY FUNDING/COMPETING INTERESTS: No specific funding was received to undertake this study. The authors report no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.
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BACKGROUND: We aimed to locate, appraise, and synthesize the available literature to assess the functional outcome of modular bicompartmental knee arthroplasty (BKA) compared to total knee arthroplasty (TKA) for medio-patellofemoral osteoarthritis. METHODS: After an extensive literature search based on electronic databases such as MEDLINE, EMBASE, CINAHL, and PubMed, and grey literature, 9 articles satisfied our selection criteria which included 1 randomized controlled trial, 1 prospective cohort, 3 retrospective cohort, and 4 case series. Narrative synthesis was performed due to clinical, methodological, and statistical heterogeneity among the included studies. RESULTS: There were 331 participants (341 knees) in this systematic review. BKA group included 229 patients (239 knees) and TKA group included 102 patients (102 knees). The quality of included studies ranged from moderate to very low as per GRADE (grading of recommendations, assessment, development, and evaluation working group) score with low to high risk of bias. Most of the studies showed comparable functional outcome in BKA compared to TKA such as Knee Society Score, Knee Osteoarthritis and Outcome Score, Short Form-36 score, and revision surgery in short-term to midterm follow-up. BKA patients achieved better range of movement and forgotten knee status than TKA patients. It resulted in longer operative time, but less intraoperative blood loss. Long-term series showed 95.1% survivorship of BKA at 5 years and 58% at 17 years. CONCLUSION: Current evidence suggests that modular BKA provides comparable functional outcome to TKA at short-term to midterm follow-up, however, with poor long-term survivorship.
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Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Osteoartritis de la Rodilla , Humanos , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/cirugía , Estudios Prospectivos , Rango del Movimiento Articular , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
OBJECTIVE: The aim of this study was to review the radiological alignment outcomes of patient Specific (PS) cutting blocks and Standard Instrumentation in Primary Total Knee Arthroplasty. METHODS: We hypothesized that the use of PS techniques would significantly improve sagittal, coronal and rotational alignment of the prosthesis on short term. We performed a systematic review and a meta-analysis including all the randomised controlled trials (RCT) using PS and standard (ST) total knee arthroplasty to date. RESULTS: A total of 538 PS TKA and 549 ST TKA were included in the study. Statistical analysis of the outliers for femoral component sagittal, coronal and rotational positioning, tibial component sagittal and coronal positioning and the overall mechanical axis were assessed. We found that there was no significant benefit from using PS instrumentation in primary knee arthroplasty to aid in the positioning of either the tibial or femoral components. Furthermore sagittal plane tibial component positioning was worse in the PS than the traditional ST group. CONCLUSION: Our results suggest that at present PS instrumentation is not superior to ST instrumentation in primary total knee arthroplasty. LEVEL OF EVIDENCE: Level 1, Systematic review of therapeutic studies.
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Artroplastia de Reemplazo de Rodilla/métodos , Articulación de la Rodilla/diagnóstico por imagen , Prótesis de la Rodilla , Osteoartritis de la Rodilla/cirugía , Radiografía/métodos , Cirugía Asistida por Computador/métodos , Estudios de Seguimiento , Humanos , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/diagnóstico por imagen , Factores de TiempoRESUMEN
BACKGROUND: The Walch classification is the most recognized means of assessing glenoid wear in preoperative planning for shoulder arthroplasty. This classification relies on advanced imaging, which is more expensive and less practical than plain radiographs. The purpose of this study was to determine whether the Walch classification could be accurately applied to x-ray images compared with magnetic resonance imaging (MRI) as the gold standard. We hypothesized that x-ray images cannot adequately replace advanced imaging in the evaluation of glenoid wear. METHODS: Preoperative axillary x-ray images and MRI scans of 50 patients assessed for shoulder arthroplasty were independently reviewed by 5 raters. Glenoid wear was individually classified according to the Walch classification using each imaging modality. The raters then collectively reviewed the MRI scans and assigned a consensus classification to serve as the gold standard. The κ coefficient was used to determine interobserver agreement for x-ray images and independent MRI reads, as well as the agreement between x-ray images and consensus MRI. RESULTS: The inter-rater agreement for x-ray images and MRIs was "moderate" (κ = 0.42 and κ = 0.47, respectively) for the 5-category Walch classification (A1, A2, B1, B2, C) and "moderate" (κ = 0.54 and κ = 0.59, respectively) for the 3-category Walch classification (A, B, C). The agreement between x-ray images and consensus MRI was much lower: "fair-to-moderate" (κ = 0.21-0.51) for the 5-category and "moderate" (κ = 0.36-0.60) for the 3-category Walch classification. DISCUSSION: The inter-rater agreement between x-ray images and consensus MRI is "fair-to-moderate." This is lower than the previously reported reliability of the Walch classification using computed tomography scans. Accordingly, x-ray images are inferior to advanced imaging when assessing glenoid wear.
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Imagen por Resonancia Magnética , Osteoartritis/diagnóstico por imagen , Osteoartritis/patología , Escápula/diagnóstico por imagen , Escápula/patología , Articulación del Hombro , Adulto , Artroplastia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Osteoartritis/clasificación , Osteoartritis/cirugía , Radiografía , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
PURPOSE: Posterior horn meniscal tears are commonly found in conjunction with anterior cruciate ligament (ACL) injury. Some believe tears in the posterior meniscocapsular zone, coined ramp lesions, are important to knee stability. The purpose of this study was to determine whether pre-operative MRI evaluation was able to accurately and reproducibly identify ramp lesions. METHODS: Three blinded reviewers assessed MRIs twice for the presence of ramp lesions in patients undergoing ACL reconstruction. Sensitivity, specificity, negative predictive value, and positive predictive value for MRI were calculated based on arthroscopic diagnosis of a ramp lesion. Intra-class correlation coefficient was calculated to assess intra- and interobserver reliability of the MRI assessment between the three examiners. Significance was set at p < 0.05. RESULTS: Ninety patients met inclusion criteria (45 males, 45 females, mean age 28.0 years). Thirteen of these patients had arthroscopy-confirmed ramp lesions, while the other 77 had other meniscal pathology. Sensitivity of detecting a ramp lesion on MRI ranged from 53.9 to 84.6%, while specificity was 92.3-98.7%. Negative predictive value was 91.1-97.4%, while positive predictive value was 50.0-90.0%. Inter-rater reliability between three reviewers was moderate at 0.56. The observers had excellent intra-rater reliability ranging from 0.75 to 0.81. CONCLUSIONS: This study demonstrates high sensitivity and excellent specificity in detecting meniscal ramp lesions on MRI. Ramp lesions are likely more common and may have greater clinical implications than previously appreciated; the outcomes of untreated lesions must be investigated. Pre-operative identification of ramp lesions may aid clinicians in surgical planning and patient education to improve outcomes by addressing pathology which may have otherwise been missed. LEVEL OF EVIDENCE: III.
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Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Meniscos Tibiales/diagnóstico por imagen , Lesiones de Menisco Tibial/diagnóstico por imagen , Adolescente , Adulto , Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Meniscos Tibiales/cirugía , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Lesiones de Menisco Tibial/cirugía , Adulto JovenRESUMEN
Despite abundant biological, biomechanical, and clinical research, return to sport after anterior cruciate ligament (ACL) injury remains a significant challenge. Residual rotatory knee laxity has been identified as one of the factors responsible for poor functional outcome. To improve and standardize the assessment of knee instability, a variety of instability scoring systems is available. Recently, devices to objectively quantify static and dynamic clinical exams have been developed to complement traditional subjective grading systems. These devices enable an improved evaluation of knee instability and possible associated injuries. This additional information may promote the development of new treatment algorithms and allow for individualized treatment. In this review, the different subjective laxity scores as well as complementary objective measuring systems are discussed, along with an introduction of injury to an individualized treatment algorithm.