1,720,982 research outputs found
Post-operative periprosthetic humeral fractures after reverse shoulder arthroplasty: A review of the literature
No full textBackground and aim of the work: Post-operative periprosthetic shoulder fractures incidence is gradually raising due to aging of population and increasing of reverse total shoulder arthroplasty (RTSA). Management of this complication represents a challenge for the orthopedic surgeon. Aim of the present study is to critically review the recent literature about epidemiology, risk factors, diagnosis, management and outcome of post-operative periprosthetic humeral fractures occurring on RTSA. Methods: A systematic search of Em-base, Medline and Pubmed was performed by two reviewers who selected the eligible papers favoring studies published in the last ten years. Epidemiology, risk factors, diagnostic features, clinical management and outcome of different techniques were all reviewed. Results: 31 studies including reviews, meta-analysis, case reports, clinical and biomechanical studies were selected. Conclusions: Correct clinical management requires adequate diagnosis and evaluation of risk factors. Conservative treatment is rarely indicated. Locking plate fixation and revision arthroplasty are both valuable treatment methods. Surgical technique should be chosen considering age and functional demand, comorbidities, fracture morphology and location, bone quality and stability of the implant. Given the correct indication all surgical treatment can lead to satisfactory clinical and radiographic results despite a relevant complication rate. (www.actabiomedica.it)
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
Three single loops enhance the biomechanical behavior of the transtibial pull-out technique for posterior meniscal root repair.
No full textPurpose: To investigate the effect of applying an additional suture to enhance the biomechanical behavior of the suture–meniscus construct used during the transtibial pull- out repair technique.
Methods: A total of 20 fresh-frozen porcine tibiae with intact medial menisci were used. In one half of all speci- mens (N = 10), two non-absorbable sutures were passed directly over the meniscal root from the tibia side of the meniscus to the femoral side (2SS). In other ten specimens, three sutures were passed over the meniscal root (3SS). All specimens were subjected to cyclic loading followed by load-to-failure testing. Displacement of the construct was recorded at 100, 500, and 1000 cycles. Further, stiffness (500–1000 cycles) and ultimate load and modes of failure of the suture–meniscus construct were also recorded. Results: There was no statistically significant difference between the Group 2SS and Group 3SS at the 1st (1.6±0.7vs1.4±0.4mm)andthe100thcycle(2±0.7 vs 1.8 ± 0.4 mm). At 500 and 1000 cycles, the 2SS fixa- tion technique resulted in significantly more displacement than the 3SS fixation technique (2.8 ± 0.6 vs 2.3 ± 0.5 mm; 3.1 ± 0.7 vs 2.5 ± 0.5 mm) (p\0.05). No differences between two groups were noted concerning ultimate load to failure and stiffness (500–1000 cycles).
Conclusion: Three single sutures technique provided superior biomechanical properties compared with the two single sutures technique during the conducted fatigue tests. Clinical relevance Applying three simple stitches during meniscal root repair might be beneficial for healing of the posterior meniscal root, potentially reducing the post-op- erative immobilization time
Facio-auriculo-vertebral anomalad and pulmonary artery sling. A hitherto undescribed but probably non-casual association
No full textBiomechanical comparison between the modified rolling-hitch and the modified finger-trap suture techniques
No full textPurpose: The purpose of this study was to characterize the biomechanical effect of two grasping suture techniques used during ligament reconstruction: the modified rolling-hitch (MRH) and the modified finger-trap (MFT). Methods: Flexor profundus tendons were harvested from fresh pig hind-leg trotters. Each specimen was mounted on an electro-mechanic universal testing machine (Instron 3367). In half of all tendons (15 specimens), the suture was passed around the tendon following the MRH knot (Group 1). In the remaining half of all tendons (15 specimens), the suture was passed over a distance of 30 mm according to the MFT suture technique (Group 2). As per standard intra-operative technique, a 1 cm residual tendon stub was left free from suture in all samples. All specimens were preconditioned to a load of 50 N for 10 min, followed by three cycles loading between 50 and 120 N. At this point, each sample was cyclically tensioned between 35 and 240 N, at 1 Hz for 200 cycles. Load-to-failure test was then carried out at a rate of 200 mm/min. Results: Rupture of the suture material at the knot was the mode of failure in all specimens during the loaded to failure test. Significant difference was found between Group 1 vs Group 2 for the elongation between the 0th cycle and 10th cycle, the elongation between the 10th cycle and 200th cycle, the mean stiffness at the 10th cycle, and the mean stiffness at the 190th cycle. No significant differences were noted between Group 1 and Group 2 concerning the ultimate load-to-failure. Conclusion: This study showed that both suture methods appear to be biomechanically effective in a porcine tendon model. However, the single-knot grasping technique (MRH) provided superior biomechanical properties compared with the MFT technique
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