1,721,145 research outputs found
Surgical hip dislocation vs arthroscopy for fixation of subfoveal femoral head fractures
No full textBackground. Reduction and fixation of Pipkin type I femoral head fractures may be performed either via surgical dislocation either via hip arthroscopy but to our knowledge no studies compared those techniques. Aim of our study is to compare (1) Fracture reduction quality, (2) modified Harris hip score at a minimum of 2 years, and (3) Frequency of complications in a case series of patients with femoral head fractures treated with those approaches. Methods Five cases of arthroscopic fixation of femoral head fracture (AG) have been compared with our historical cohort (8 patients, SDG). Patient demographic, injury, and surgical variables as well as complications were recorded and retrospectively evaluated. Radiographic outcome was scored according to Matta’s criteria on postoperative radiographs and clinical outcomes were evaluated with the modified Harris hip score. Results Fracture reduction was anatomic in five hips and imperfect in two in the SDG while four hip were classified as anatomic and one imperfect in the AG. The mean clinical scores were significantly different between the two groups (p=0.03): 88 points in SDG (SD 7) and 94 points in AG (SD 5). In the SDG, one patient developed symptomatic femoral head AVN and one had heterotopic ossification. In the AG, no complication (heterotopic ossification and AVN) but one grade I sign of arthritis were noted. Conclusions Arthroscopic reduction and fixation of Pipkin type I fracture shows radiographic results compa-rable to surgical dislocation but better clinical results and lower rates of comorbidity. (www.actabiomedica.it)
Decision/therapeutic algorithm for acetabular revisions
No full textBackground and aim: Paprosky’s classification is currently the most used classification for periacetabular bone defects but its validity and reliability are widely discussed in literature. Aim of this study was to introduce a new CT-based Acetabular Revision Algorithm (CT-ARA) and to evaluate its validity. The CT-ARA is based on the integrity of five anatomical structures that support the acetabulum. Classification’s groups are defined by the deficiency of one or more of these structures, treatment is based on those groups. Methods: In 105 patients the validity of the CT-ARA was retrospectively evaluated using preoperative X-rays, CT-scan and surgery reports. The surgical indications suggested by Paprosky’s algorithm and by CT-ARA were compared with the final surgical technique. Patients were divided into two groups according to time of surgery. Results: We reported concordance of indications in 56,2% of cases with the Paprosky’s algorithm and in 63,8% of cases with the CT-ARA. Analysing only the most recent surgeries (group 2), we reported even higher differ-ence of concordance (67,3% Paprosky’s algorithm and 83,7% CT-ARA). The concordance of the CT-ARA among Group 1 and Group 2 resulted significantly different. Conclusions: the CT-ARA may be a useful tool for the preoperative decision-making process and showed more correlation with performed surgery compared to the Paprosky’s algorithm
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
Dynamic evaluation of THA components by prosthesis impingement software (PIS)
Full text linkBackground and aim of the work: Implant dislocation in total hip arthroplasties (THA) is a common concern amongst the orthopedic surgeons and represents the most frequent complication after primary implant. Several causes could be responsible for the dislocation, including the malpositioning of the components. Conventional imaging techniques frequently fail to detect the mechanical source of dislocation mainly because they could not reproduce a dynamic evaluation of the components. The purpose of this study was to elaborate a diagnostic tool capable to virtually assess if the range of movement (ROM) of a THA is free from anterior and/or superior mechanical impingement. The ultimate aim is to give the surgeon the possibility to weigh the mechanical contribution in a THA dislocation. Methods: A group of patients who underwent THA revision for acute dislocation was compared to a group of non-dislocating THA. CT scans and a virtual model of each patient was obtained. A software called “Prosthesis Impingement Simulator (PIS)” was developed for simulating the (ROM) of the prosthetic hip. The ROM free of mechanical impingement was compared between the two groups. Results: The PIS test could detect the dislocations with a sensitivity of 71,4%, and a specificity of 85,7%. The Fisher’s exact test showed a p-value of 0,02. Conclusion: The PIS seems to be an effective tool for the determination of hip prosthetic impingement, as the main aid of the software is the exclusion of mechanical causes in the event of a dislocation
Arthroscopic reduction and fixation of partial posterior wall acetabular fractures
No full textBACKGROUND AND AIM: Reduction and fixation of partial posterior wall fracture is usually performed with an open posterolateral approach. When the fragment may be fixed without a plate (with screws only), reduction and fixation may be also achieved via hip arthroscopy. To our knowledge no study described this technique. Aim of our study is to describe the surgical technique and to present the achieved outcomes and the occurred complications. METHODS: Six cases of arthroscopic fixation of partial posterior wall fracture have been reviewed for the purpose of this study. Patients were treated arthroscopically if the fragment was not bigger than 25% of the posterior wall. Patient demographic, injury, and surgical variables as well as complications were recorded and retrospectively evaluated. Radiographic outcome was scored according to Matta's criteria on postoperative radiographs and clinical outcomes were evaluated with the modified Harris hip score. RESULTS: Fracture reduction was classified as anatomic on post-operative x-rays in all patients. The mean clinical score was 98 points at one year follow-up. No patient developed symptomatic femoral head AVN, none had heterotopic ossification. In one patients a screw breakage occurred without clinical complications. CONCLUSIONS: Arthroscopic reduction and fixation of partial posterior wall fracture is an effective treatment and showed good outcomes if a careful patients' selection is done
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