1,720,957 research outputs found
Relative Femoral Neck Lengthening in Legg-Calvé-Perthes Total Hip Arthroplasty
No full textBackground: Total hip replacement (THR) in patients with a history of Legg-Calv e-Perthes disease can be
a technically challenging procedure due to the distorted hip morphology. We propose a technique in
which THR is preceded by a modified relative femoral neck lengthening (RFNL) procedure. Hereby, we
aim to restore the biomechanical parameters.
Methods: Twenty-eight patients underwent RFNL in preparation of a second-stage THR between
December 2011 and September 2019. The mean age was 38.1 ± 11.4 years. Radiographs were analyzed for
centrotrochanteric distance, lateral displacement of the greater trochanter, and leg length discrepancy to
assess the biomechanical restoration. Complication rate, reoperation rate, and patient-reported outcome
measures were measured.
Results: Mean centrotrochanteric distance increased from 18.7 ± 6.7 mm preoperatively to 1.9 ± 9.0
mm (P < .001) after RFNL and to 11.4 ± 10.4 mm after THR (P < .001). Mean lateral displacement of the
greater trochanter increased from 34.2 ± 8.1 mm preoperatively to 42.4 ± 5.2 mm (P < .001) after RFNL
and to 49.9 ± 8.3 mm after THR (P < .001). Leg length discrepancy decreased from 17.5 ± 10.5 mm to 2.7 ±
2.2 mm after THR (P < .001). Mean Harris Hip Score improved from 56.9 ± 17.6 preoperatively to 89.4 ±
10.7 at the latest follow-up (P < .001). Eight patients (8 hips) postponed THR because of sufficient clinical
improvement, at a mean follow-up of 4.2 ± 2.1 years. Two hips needed a revision RFNL due to non-union
(7.1%), and 1 hip replacement was revised due to a deep infection (5.0%).
Conclusions: RFNL prior to THR in patients with end-stage osteoarthritis following Legg-Calv e-Perthes
disease allows for utilizing regular implants with straight access to the femoral canal, with restored
biomechanics and restoration of leg length. The prominent overhanging greater trochanter is reduced to
prevent postoperative extra-articular impingement.RFNL prior to THR in patients with end-stage osteoarthritis following LCPD allows for utilizing regular implants with straight access to the femoral canal, with restored biomechanics and restoration of leg length
Combined lateral extra-articular tenodesis and anterior cruciate ligament reconstruction : risk of osteoarthritis
No full textPurpose Lateral extra-articular tenodesis (LET) procedure, combined with an intra-articular reconstruction of the anterior cruciate ligament (ACL), is used to reduce rotational laxity and the risk of graft failure. However, concern of overtightening of the lateral compartment and subsequent osteoarthritis remains. The aim of this study is to evaluate the degenerative changes in the lateral compartment and to compare the clinical and radiographical results between two LET techniques. Methods Eighty-three patients (86 knees) were retrospectively reviewed at a mean of 67.7 months (range 49-85 months). Forty-two knees had an ACL reconstruction combined with a LET procedure according to the modified Lemaire technique and 44 knees according to the modified Coker-Arnold technique. IKDC, Lysholm, Tegner and VAS scores were used. Osteoarthritis was radiographically evaluated by the Kellgren-Lawrence classification. Results There were 12 patients (28.6%) in the modified Lemaire subgroup and 13 patients (29.5%) in the modified Coker-Arnold subgroup that had doubtful or mild radiologic signs of osteoarthritis. No patients had moderate or severe signs at final follow-up. There was no significant difference in radiological signs of osteoarthritis. In the modified Lemaire subgroup, we report a mean IKDC of 86.31 (+/- 13.794), a mean Lysholm of 87.83 (+/- 12.802) and a mean Tegner of 5.38 (+/- 2.556). In the modified Coker-Arnold subgroup, a mean IKDC of 87.27 (+/- 11.653), a mean Lysholm of 91.89 (+/- 8.035) and a mean Tegner of 5.16 (+/- 2.420) were reported. There were no statistical significant differences between both techniques. In eight patients, a complication was identified, 3 of which had a failure of the ACL reconstruction. Conclusions The chosen LET-technique seems to have minimal effect on both the clinical and the radiographic results. The LET is a safe procedure, and it does not increase the risk of osteoarthritis in the lateral compartment
The peri-articular muscle envelope of the hip (PAME) shows atrophy in patients with refractory groin pain after iliopsoas tenotomy
No full textBackground:
Iliopsoas tenotomy is commonly used to address refractory groin pain resulting from iliopsoas tendinopathy. However, consensus and high-level research on its effectiveness are lacking, with concerns about poor outcomes and complications. Little is known of the effects of iliopsoas tenotomy on the peri-articular muscle envelope of the hip. As the iliopsoas loses its function as the most important hip flexor, the rectus femoris takes over its function, which makes the rectus prone to tendinopathy.
Methods:
A retrospective review of patients (n = 17) undergoing iliopsoas tenotomy between January 2016 and January 2021 was conducted. Pelvic MRI scans were evaluated for muscle quality and volume using a Quartile classification system and cross-sectional area (CSA) measurements. Reliability tests determined the most consistent reference points. Statistical analyses assessed changes between ipsilateral and contralateral sides.
Results:
Following iliopsoas tenotomy, significant reduced cross sectional area was seen in the psoas, iliacus, gluteus minimus, gluteus maximus, rectus femoris, piriformis, obturator internus and obturator externus. Significant increased fatty degeneration was seen in the psoas, iliacus, gluteus minimus, tensor fascia latae, piriformis, obturator internus and obturator externus. The gluteus medius was the only muscle where no difference was seen in the cross sectional area or the fatty degeneration. 15 patients (88%) presented with rectus tendinopathy and 8 of these patients had a surgical debridement of the rectus femoris.
Conclusions:
Our findings reveal that patients with persistent groin pain following iliopsoas tenotomy exhibit changes in the peri-articular muscle envelope, displaying atrophy or fatty degeneration in all muscles except the gluteus medius. Awareness of potential risks is crucial when contemplating iliopsoas tenotomy. Persistent groin pain after iliopsoas tenotomy may be linked to secondary rectus femoris tendinopathy. Caution is recommended in the consideration of iliopsoas tenotomy for patients with pre-existing iliopsoas tendinopathy.The author(s) received no financial support for the research, authorship and/or publication of this article
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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