1,720,963 research outputs found
Knee flexion after total knee arthroplasty reduces blood loss
No full textPurpose: Extensive blood loss after total knee arthroplasty (TKA) may be a potential problem since it leads to anaemia, increased need for transfusion and prolonged hospitalization. Aim of this study was to investigate the effects of postoperative knee flexion after TKA on blood loss and the need for transfusion. Methods: One hundred consecutive patients undergoing primary TKA from 2012 to 2013 were randomizely divided into two groups. In one group, the knee was extended for the first 6 h after surgery, whereas in the other was flexed at 90° for the same time. Two doses of endovenous tranexamic acid were administered in all subjects. Patients were homogeneous for all the possible confounding factors. Results: Calculated blood loss was 846 ± 197 (ml) in the flexion group and 1,242 ± 228 (ml) in the extension group (p < 0.05). Drop of haemoglobin levels at 24 h in the study group and the control group was 1.9 ± 0.8 (g/dl) and 3.0 ± 0.5 (g/dl), respectively (p < 0.01). Drop of haematocrit at 24 h was 4.5 ± 0.2 (%) in the flexion group and 6.7 ± 0.3 (%) in the extension group (p < 0.05). Blood transfusion was necessary in 5 patients in the control group and was not necessary in any patient of the study group. Average knee flexion at day 7 was 105° ± 4° in the flexion group and 98° ± 7° in the extension group. Conclusion: Knee flexion at 90° after TKA, associated with the intraoperative use of tranexamic, acid is an effective method to reduce blood loss and the need for blood transfusion. The routine use of the present protocol is effective in reducing social costs and length of hospitalization of TKA procedures. Level of evidence: Prospective comparative study, Level I. © 2014 Springer-Verlag Berlin Heidelberg
Patellar resurfacing complications in total knee arthroplasty
No full textPurpose: The ideal management of the patella during total knee arthroplasty (TKA) is still controversial. Patellar retention is generally associated with an increased rate of anterior knee pain; however, patient satisfaction is similar in cases of replacement or retention. When the patella is replaced, potential severe complications can occur. Aim of this study was to retrospectively review results of a continuous series of patients having been treated with TKA and patella resurfacing. Methods: The charts of 1,600 consecutive total knee prostheses were analysed to evaluate the rate of patellar resurfacing. All implants were posterior stabilized; 310 patients having received a patellar replacement were reviewed at follow-up (FU) examination. Complete physical examination as well as administration of the Hospital for Special Surgery (HSS) score was performed. X-rays analysis included weightbearing anteroposterior (AP) and lateral views of the injured knee and bilateral skyline views at 30 flexion. Results: Two hundred and eighty patients were available for clinical and imaging investigation at an average FU of 96 (58-144) months. Mean age at the time of surgery was 70 (62-80) years. Mean HSS score was 85.9 ± 7.6. The overall rate of patellofemoral complications was 7 % (19 cases); 13 patients claimed anterior knee pain, five had symptomatic patellar maltracking and one had patellar component loosening. Conclusion: Our data are in accordance with those available in the literature. Recent meta-analyses demonstrated lower risk of re-operation after patellar resurfacing. However, when complications of the resurfaced patella occur, they can be potentially catastrophic events. © 2013 Springer-Verlag Berlin Heidelberg
Medial capsule reefing in patellar instability
No full textResults: All patients were reviewed at an intermediate follow-up of 72 months. Average Kujala score improved from 72.9 ± 15.0 to 88.4 ± 7.6 (p < 0.0001), average Larsen score from 15.0 ± 2.5 to 17.2 ± 2.2 (p < 0.002), average Lysholm from 63.8 ± 16.7 to 87.9 ± 11.7 (p < 0.0001) and average Fulkerson score from 69.5 ± 21.5 to 90.8 ± 9.8 (p < 0.0001). No intraoperative or postoperative complications were recorded. Ninety per cent of patients were very satisfied or satisfied with their functional result. Twenty-eight patients were reviewed at the final follow-up, 120 months after surgery. Average Kujala was 87.7 ± 8.8 (p < 0.0001), average Larsen was 16.8 ± 2.7 (p < 0.01), average Lysholm was 87.6 ± 14.3 (p < 0.0001), and average Fulkerson was 87.2 ± 13.9 (p < 0.0001). Almost 86 % of patients were very satisfied or satisfied with their result. However, slight deterioration of the outcomes over time was observed.Conclusion: At the final follow-up, the outcomes of all-arthroscopic technique were significantly improved from preoperative values; however, they were slightly inferior at the 72 months follow-up. This slight deterioration of the outcomes may be the consequence of the reduction in physical activities.Level of evidence: Case series, Level IV.Purpose: The efficacy of medial capsule reefing in the treatment of patellar instability is well documented. Aim of the present study was to prospectively evaluate the outcomes of an all-arthroscopic medial capsule reefing technique in young patients with painful patella syndrome and potential patellar instability.Methods: Thirty patients with painful patellar syndrome and potential patellar instability having undergone a minimum of 6 months of intensive rehabilitation were enrolled in the present study. All subjects were evaluated with physical examination, clinical and functional outcomes and complete imaging study
Antibiotic-loaded bone cement reduces risk of infections in primary total knee arthroplasty? A systematic review
No full textPurpose: Antibiotic-loaded bone cement has been widely used for the treatment of infected knee replacement, but its routine use in primary TKA remains controversial. The aim of this systematic review was to analyze the literature about the antimicrobial efficacy and safety of antibiotic-loaded bone cement for its prophylactic use in primary TKA. Methods: A detailed and systematic search of the Pubmed, Medline, Cochrane Reviews and Google Scholar databases had been performed using the keyword “total knee arthroplasty” “total knee replacement” “total knee prosthesis” and “antibiotic-loaded bone cement” with no limit regarding the year of publication. We used modified Coleman scoring methodology (mCMS) to identify scientifically sound articles in a reproducible format. The review was limited to the English-language articles. Results: Six articles met inclusion criteria. In total, 6318 arthroplasties were included in our study. 3217 of these arthroplasties received antibiotic-loaded bone cement and 3101 arthroplasties served as the control. There was no statistical difference between the two groups in terms of the incidence of deep or superficial surgical site infection. The average mCMS score was 67.6, indicating good methodological quality in the included studies. Conclusions: Present review did not reveal any significant difference in terms of rate of deep or superficial surgical site infection in patients receiving antibiotic-loaded bone cement compared with the control (plain bone cement) during primary TKA. The clinical relevance of this study was that the use of antibiotic-loaded bone cement did not significantly reduce the risk of infection in primary TKA. Level of evidence: III.Purpose: Antibiotic-loaded bone cement has been widely used for the treatment of infected knee replacement, but its routine use in primary TKA remains controversial. The aim of this systematic review was to analyze the literature about the antimicrobial efficacy and safety of antibiotic-loaded bone cement for its prophylactic use in primary TKA. Methods: A detailed and systematic search of the Pubmed, Medline, Cochrane Reviews and Google Scholar databases had been performed using the keyword “total knee arthroplasty” “total knee replacement” “total knee prosthesis” and “antibiotic-loaded bone cement” with no limit regarding the year of publication. We used modified Coleman scoring methodology (mCMS) to identify scientifically sound articles in a reproducible format. The review was limited to the English-language articles. Results: Six articles met inclusion criteria. In total, 6318 arthroplasties were included in our study. 3217 of these arthroplasties received antibiotic-loaded bone cement and 3101 arthroplasties served as the control. There was no statistical difference between the two groups in terms of the incidence of deep or superficial surgical site infection. The average mCMS score was 67.6, indicating good methodological quality in the included studies. Conclusions: Present review did not reveal any significant difference in terms of rate of deep or superficial surgical site infection in patients receiving antibiotic-loaded bone cement compared with the control (plain bone cement) during primary TKA. The clinical relevance of this study was that the use of antibiotic-loaded bone cement did not significantly reduce the risk of infection in primary TKA. Level of evidence: III
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
