Journal of Knee Surgery最新文献

{"title":"Is There a Need for a Central Stem within the Keel of Primary Tibial Baseplates in Total Knee Arthroplasty.","authors":"Arun Kannan, Peter Lewis, Carl Holder, Sophia Corfield, Varun Roheet, Stephen John McMahon","doi":"10.1055/a-2908-1829","DOIUrl":"https://doi.org/10.1055/a-2908-1829","url":null,"abstract":"<p><strong>Abstract: </strong>Clinical studies suggest a role for the keel of the tibial component in preventing aseptic loosening in total knee arthroplasty (TKA). To analyze the role of a central stem within the keel, we compared two designs of tibial components for the Triathlon TKA (Stryker): standard keel components that have a central stem and fins (Triathlon universal tibial baseplate) and finned components that have fins alone and lack a central stem (Triathlon primary tibial baseplate). Questions: (1) is there a difference in all-cause revision rate or revision rates for loosening? (2) Is there a difference in revision rates when stratified by sex, body mass index (BMI) or insert conformity? We used retrospective data from the Australian Orthopaedic Association National Joint Replacement Registry of 76,710 minimally stabilized cemented TKAs performed without stem extensions for primary osteoarthritis from September 1999 to December 2023. The mean age of patients was 69.3 ± 8.9 years, and 59.6% were females. The mean follow-up was 5.6 years. Cumulative percent revision from Kaplan-Meier estimates was used to compare the revision rates between finned and standard keel tibial components. Hazard ratios (HR), adjusted for sex and age, were used for comparison. There was no difference in the overall revision rate between standard and finned tibial components (HR: 1.05, 95% confidence interval [CI]: 0.74-1.48, <i>p</i> = 0.779) or in revision rates for loosening with the numbers available for the study. Stratification by sex, BMI, and insert conformity (cruciate-retaining and condylar-stabilizing) did not show a difference between the groups. Females had a marginally higher risk of revision than males when finned components were used (HR: 1.33, 95% CI: 1.01-1.75, <i>p</i> = 0.045). Central stems within the keel of cemented tibial components do not alter the survivorship of minimally stabilized TKA.</p>","PeriodicalId":48798,"journal":{"name":"Journal of Knee Surgery","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149117048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"When Is Distal Femoral Replacement Indicated? Insights From Periprosthetic and Native Distal Femoral Fractures Around the Knee.","authors":"Jacob Shermetaro, James Germano, Giles R Scuderi","doi":"10.1055/a-2886-7845","DOIUrl":"10.1055/a-2886-7845","url":null,"abstract":"<p><strong>Abstract: </strong>The incidence of periprosthetic and native distal femoral fractures is rising with the increasing utilization of total knee arthroplasty and an aging global population. These injuries present significant clinical challenges, most commonly affecting elderly patients. While fixation-based strategies remain widely employed, distal femoral replacement has emerged as an increasingly utilized alternative. The purpose of this narrative review is to examine the current indications, implant considerations, and clinical evidence supporting the use of distal femoral replacement in the management of both periprosthetic and native distal femoral fractures. Distal femoral replacement demonstrates broadly equivalent outcomes to conventional fixation and allows for immediate full weight-bearing and expedited rehabilitation, which is particularly important in elderly patients. Surgeon expertise, familiarity with available implant systems, and a coordinated multidisciplinary perioperative approach are important contributors to optimizing outcomes. Distal femoral replacement is a safe, reliable, and increasingly relevant treatment strategy for carefully selected patients presenting with periprosthetic or native distal femoral fractures. It is most appropriately indicated in elderly or low-demand patients with severe metaphyseal comminution, significant osteoporosis, preexisting osteoarthritis, a loose or malrotated femoral component, or fractures not amenable to stable internal fixation. Future prospective studies and randomized controlled trials are needed to better define patient selection criteria, standardize outcome reporting, and formally evaluate cost-effectiveness.</p>","PeriodicalId":48798,"journal":{"name":"Journal of Knee Surgery","volume":" ","pages":"631-634"},"PeriodicalIF":1.4,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148228854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Management of Distal Femoral Periprosthetic Fractures after Total Knee Arthroplasty: Fixation versus Revision Reconstruction.","authors":"Philip Sakalian, James Germano, Giles R Scuderi","doi":"10.1055/a-2886-7879","DOIUrl":"10.1055/a-2886-7879","url":null,"abstract":"<p><strong>Abstract: </strong>The incidence of periprosthetic distal femur fractures after total knee arthroplasty (TKA) is increasing in parallel with the increasing number of primary TKA procedures being performed. This number will continue to rise going forward. Treatment decisions depend on patient factors, fracture characteristics, and implant stability. It is important to have a thorough understanding of the available modalities for treatment, including their indications, advantages, and disadvantages, to effectively manage these injuries and optimize outcomes. Nonoperative treatment is indicated in select cases but is generally associated with inferior outcomes, including higher rates of nonunion, malunion, and medical complications secondary to prolonged immobility. Operative management is the gold standard, and options include open reduction internal fixation (ORIF) with plates and screws, intramedullary nailing (IMN), nail/plate combination constructs, and revision arthroplasty with distal femoral replacement (DFR). Locking plate fixation can be useful for comminuted or more complex fractures and poor bone stock, while IMN is less invasive, preserving biology and allowing for earlier mobilization in some cases, especially when combined with plating. DFR is indicated for cases of implant loosening or severe bone loss and has been associated with more reliable early weight-bearing at the expense of increased risks for infection and revision arthroplasty. Overall, each of the treatment modalities discussed is a viable option for the management of these complex injuries. Management should ultimately be tailored to the individual patient. The surgeon should consider patient factors, fracture characteristics, implant stability, and their own level of expertise when deciding on treatment.</p>","PeriodicalId":48798,"journal":{"name":"Journal of Knee Surgery","volume":" ","pages":"626-630"},"PeriodicalIF":1.4,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148310026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of Internet+ Rehabilitation on Arthroscopic Treatment Outcomes for Knee Meniscal Injuries and Factors Influencing Knee Osteoarthritis.","authors":"Lina Qiu, Huadi Yuan, Luping Tang","doi":"10.1055/a-2835-3645","DOIUrl":"10.1055/a-2835-3645","url":null,"abstract":"<p><strong>Abstract: </strong>This study aimed to assess the effectiveness of Internet+ rehabilitation in arthroscopic treatment for knee meniscal injuries and its influence on knee osteoarthritis (KOA) factors. A cohort of 120 patients with meniscal injuries undergoing arthroscopic treatment in the Orthopedics Department between January 2021 and December 2022 was randomly assigned to either a control group or a study group using a randomization table. The control group underwent self-rehabilitation at home, while the study group received Internet-enhanced rehabilitation. Patient compliance with rehabilitation exercises, knee joint functionality, and long-term KOA outcomes were compared between the groups. KOA status was evaluated using the Kellgren-Lawrence (K-L) grading system, categorizing grades 0 to 2 as KOA negative and grades 3 to 5 as KOA positive, to investigate factors impacting KOA. The study group demonstrated significantly higher compliance rates and Lysholm scores compared with the control group. K-L grades were notably lower in the study group, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were significantly reduced in the study group as well. The KOA-positive subgroup exhibited significantly older age and longer preoperative durations than the KOA-negative subgroup, with a notably higher proportion of Internet+ rehabilitation intervention in the study group than in the control group. Multifactorial logistic regression analysis identified advanced age and prolonged preoperative duration as risk factors for KOA, while Internet-enhanced rehabilitation intervention emerged as a protective factor against KOA. The integration of Internet+ rehabilitation in arthroscopic treatment for knee meniscal injuries substantially enhances treatment compliance and improves joint functionality. During a 12-month follow-up, internet-enhanced rehabilitation was associated with a lower occurrence and severity of KOA. Furthermore, advanced age and an extended preoperative duration represented independent risk factors for KOA, while Internet+ rehabilitation was independently associated with a reduced odds of KOA in multivariate analysis.</p>","PeriodicalId":48798,"journal":{"name":"Journal of Knee Surgery","volume":" ","pages":"662-668"},"PeriodicalIF":1.4,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147786459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Risk Factors for Distal Femoral Periprosthetic Fractures after Total Knee Arthroplasty: A Systematic Review of Patient and Implant Variables.","authors":"Lawrence Jajou, James Germano, Giles R Scuderi","doi":"10.1055/a-2871-7249","DOIUrl":"10.1055/a-2871-7249","url":null,"abstract":"<p><strong>Abstract: </strong>The number of total knee arthroplasty (TKA) procedures performed continues to rise annually. As projections show a continued increase in these surgeries, it is important to identify patients at risk for certain complications. Distal femur periprosthetic fractures around TKA can pose notable morbidity to patients, while also imparting a marked burden on the health system. This systematic review aims to identify patient and implant characteristics that increase the risk of distal femur periprosthetic fractures. Three common literature databases were searched for \"distal femur periprosthetic fracture.\" The resulting studies were screened for relevance and inclusion and exclusion criteria, followed by an in-depth review of various patient and implant characteristics. Thirteen studies were included in this systematic review. Despite some variation across the studies, the most common population for distal femur periprosthetic fractures was females, over the age of 70, with the American Society of Anesthesiologists (ASA) score of III. These most often occurred in a low-energy trauma or falls from standing. Additionally, when compared to native distal femur fractures, there is evidence that periprosthetic fracture patients are older, have a higher body mass index (BMI), are more commonly osteopenic or osteoporotic, and less commonly sustain these injuries as part of polytrauma. As we continue to perform increasing numbers of TKAs, identifying patients at risk for periprosthetic fractures aids in patient counseling and preventive care. This can allow patients to optimize modifiable risk factors before and after undergoing TKA in an effort to avoid sustaining periprosthetic distal femur fractures.</p>","PeriodicalId":48798,"journal":{"name":"Journal of Knee Surgery","volume":" ","pages":"620-625"},"PeriodicalIF":1.4,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147876278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Long-Term Tunnel Widening in Anterior Cruciate Ligament Reconstruction Using Allograft and Hamstring Autograft: More Than 10 Years' Mean Follow-Up.","authors":"Enver İpek, Yusuf Altuntaş, Bahadır Balkanlı, Mehmet Alp Yüksel, Harun Akbaş, Osman Tuğrul Eren","doi":"10.1055/a-2886-8283","DOIUrl":"10.1055/a-2886-8283","url":null,"abstract":"<p><strong>Abstract: </strong>Bone tunnel widening following anterior cruciate ligament reconstruction (ACLR) is a well-recognized radiological phenomenon with multifactorial etiology. While concerns have been raised regarding potentially greater tunnel enlargement with allografts due to immune-mediated responses, evidence remains inconsistent. This study compared long-term femoral and tibial tunnel widening between hamstring autograft and allograft reconstruction at a mean follow-up exceeding 10 years. A retrospective analysis was conducted on 60 patients who underwent primary ACLR between 2011 and 2016 by a single surgeon. Group I consisted of 29 patients receiving soft tissue allografts (Achilles, tibialis anterior, or peroneus longus tendons), while Group II included 31 patients with four-strand hamstring autografts. All procedures utilized identical fixation: adjustable-loop suspension device (femur) and bioabsorbable interference screw with tibial staple. Patients with previous knee surgery, re-rupture, clinical graft failure, concomitant ligament procedures, or significant chondral lesions were excluded. Computed tomography scans at final follow-up (mean: 10.7 years) were analyzed using standardized oblique reformatted sections perpendicular to tunnel axes. Six measurements per tunnel (three levels × two planes) were averaged. Tunnel widening was expressed as absolute change (Δmm) and percentage relative to intraoperative drill bit diameter. Two blinded orthopedic surgeons performed independent measurements. Statistical analysis included Mann-Whitney U test, analysis of covariance adjusted for body mass index (BMI) and follow-up duration, categorical threshold analysis, and correlation analysis with Bonferroni correction. No significant differences were observed between groups for tibial widening (allograft 2.07 ± 1.75 mm vs. autograft 2.31 ± 1.72 mm, <i>p</i> = 0.500) or femoral widening (1.73 ± 1.48 mm vs. 2.30 ± 1.63 mm, <i>p</i> = 0.157). After adjustment for BMI and follow-up duration, between-group differences remained nonsignificant (all adjusted <i>p</i> > 0.0125 after Bonferroni correction). Categorical distribution across predefined thresholds showed similar patterns. Initial tunnel diameter inversely correlated with tibial percentage widening (<i>r</i> =-0.373, <i>p</i> = 0.003). Interobserver reliability was excellent (intraclass correlation coefficient: 0.89-0.92). At long-term follow-up, allograft and hamstring autograft demonstrated comparable tunnel widening patterns, suggesting graft selection should prioritize clinical factors beyond tunnel enlargement concerns.</p>","PeriodicalId":48798,"journal":{"name":"Journal of Knee Surgery","volume":" ","pages":"654-661"},"PeriodicalIF":1.4,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148212882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Management Strategies for Tibial Periprosthetic Fractures After Total Knee Arthroplasty.","authors":"Chase W Smitterberg, Amir H Hoveidaei, Ronald E Delanois, Michael A Mont","doi":"10.1055/a-2865-1724","DOIUrl":"10.1055/a-2865-1724","url":null,"abstract":"<p><strong>Abstract: </strong>Tibial periprosthetic fractures following total knee arthroplasty are relatively uncommon, but represent a complex and increasingly encountered complication given the growing volume of primary and revision arthroplasty procedures. These injuries present unique challenges due to compromised bone stock, implant-related constraints, and patient-specific factors such as advanced age and osteoporosis. The location of the fracture, implant stability, bone quality, and the functional needs of the patient all influence management tactics. While operative intervention is frequently necessary for displaced fractures or those linked to component loosening, nonoperative treatment may be suitable in certain individuals who have stable implants and slightly displaced fractures. Proximal tibial replacement in extreme situations, revision arthroplasty using stemmed components, and open reduction and internal fixation are surgical possibilities. This review summarizes current classification systems, treatment strategies, and outcomes, with an emphasis on practical decision-making. A treatment strategy centered first on implant stability and then on fracture pattern, bone stock, and patient factors provides the most useful framework for clinical decision-making.</p>","PeriodicalId":48798,"journal":{"name":"Journal of Knee Surgery","volume":" ","pages":"649-653"},"PeriodicalIF":1.4,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147942828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Risk Factors for Tibial Periprosthetic Fractures After Total Knee Arthroplasty: The Influence of Fixation and Implant Design.","authors":"Amir H Hoveidaei, Chase W Smitterberg, Ronald E Delanois, Michael A Mont","doi":"10.1055/a-2865-1657","DOIUrl":"10.1055/a-2865-1657","url":null,"abstract":"<p><strong>Abstract: </strong>Tibial periprosthetic fractures (PPF) after total knee arthroplasty are multifactorial, arising from a dynamic interplay between implant mechanics, fixation strategy, surgical technique, and patient bone quality. Cemented fixation, while providing immediate stability, intensifies proximal stress shielding and periprosthetic bone loss, whereas cementless fixation favors physiologic load transfer but risks early micromotion and compromised osseointegration. Stemmed implants generate distal stress concentration at the stem tip, identifying predictable fracture initiation sites. Implant geometry, particularly keel versus peg design, baseplate size, and polyethylene thickness, modulates intraoperative and early postoperative fracture risk. Metal-backed components exacerbate proximal strain reduction, while all-polyethylene designs maintain local bone density but increase interface motion. Patient factors such as low bone mineral density, preoperative valgus alignment, advanced age, and being a woman synergistically amplify mechanical vulnerabilities. Surgical technique errors, including aggressive keel preparation and oversizing, can precipitate fractures even in structurally sound bone. Recognizing these biomechanical and patient-specific interactions provides a framework to optimize implant selection, fixation methods, and operative strategies, potentially reducing tibial PPF incidence.</p>","PeriodicalId":48798,"journal":{"name":"Journal of Knee Surgery","volume":" ","pages":"640-644"},"PeriodicalIF":1.4,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147942822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epidemiology and Classification of Tibial Periprosthetic Fractures Following Total Knee Arthroplasty.","authors":"Amir H Hoveidaei, Chase W Smitterberg, Ronald E Delanois, Michael A Mont","doi":"10.1055/a-2871-7216","DOIUrl":"10.1055/a-2871-7216","url":null,"abstract":"<p><strong>Abstract: </strong>Tibial periprosthetic fractures (PPF) following total knee arthroplasty (TKA) are uncommon but clinically important complications with rising incidence parallel to the growing volume of arthroplasty procedures. Although the overall 10-year cumulative rate of PPF after primary TKA is approximately 1.7%, tibial fractures account for a small proportion yet are associated with substantial morbidity, reoperation, and infection risk. These injuries occur more frequently in revision TKA, females, and individuals who have osteoporosis or compromised bone stock. Additional risk factors include nonosteoarthritis indications, higher implant constraint, malalignment, and peri-implant bone loss. Mechanistically, most tibial PPFs result from low-energy trauma, stress insufficiency, and altered postoperative load distribution. Accurate classification is fundamental for management and prognosis. The Felix classification remains the most widely used system, integrating fracture location (Types I-IV) with implant stability (subtypes A-C). Fracture pattern reflects anatomical behavior, whereas component stability serves as the principal determinant of treatment strategy. Stable-implant fractures may be treated with fixation, whereas loose components generally require revision arthroplasty. Emerging decision frameworks, such as the Applied Step Algorithm for Periprosthetic Tibial Fractures, further incorporate bone stock and stability into structured treatment pathways. Understanding epidemiology, fracture patterns, and classification principles is essential to guide surgical planning and improve outcomes in this high-risk patient population.</p>","PeriodicalId":48798,"journal":{"name":"Journal of Knee Surgery","volume":" ","pages":"635-639"},"PeriodicalIF":1.4,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147943416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epidemiology and Classification of Distal Femoral Periprosthetic Fractures Following Total Knee Arthroplasty.","authors":"Maximillian Phillip Ganz, James Germano, Giles R Scuderi","doi":"10.1055/a-2865-1934","DOIUrl":"10.1055/a-2865-1934","url":null,"abstract":"<p><strong>Abstract: </strong>Distal femoral periprosthetic fractures (DFPF) are an increasingly prevalent complication following total knee arthroplasty (TKA), representing a significant challenge to the orthopedic community. As the volume of primary and revision TKA continues to rise globally, a clear understanding of the epidemiological landscape and standardized classification are paramount for appropriate treatment, clinical communication, and research. This review provides a focused analysis of the current epidemiological propensities of DFPF, identifying the specific patient populations and temporal trends that define these injuries. Identifying, reporting, and treating DFPF requires standardized nomenclature to classify these injuries. Currently, multiple classification systems are utilized. Each system demonstrates individual strengths and weaknesses, from simple descriptive models to management-oriented frameworks. By focusing on the relationship between fracture location, implant stability, and bone stock, these systems provide algorithmic workflow for the surgical decision-making process between internal fixation construct type or the need for revision arthroplasty. As the incidence of these complex fractures continues to rise, the integration of epidemiological data with reliable classification remains essential for optimizing surgical outcomes and developing effective preventative strategies.</p>","PeriodicalId":48798,"journal":{"name":"Journal of Knee Surgery","volume":" ","pages":"614-619"},"PeriodicalIF":1.4,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147822541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}