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An introduction to modern anterior cruciate ligament repair
No full textAbstract: Modern anterior cruciate ligament (ACL) repair was still in \u201cit\u2019s child\ub4s shoes\u201d (translation of Dutch proverb) in 2015. In the following years it became a hot topic in the orthopedic community. Excellent short-term outcomes on open ACL repair were reported in the \ub470s with open ACL repair, however high risks of failure were reported after mid-term follow-up. ACL repair was abandoned in favor of ACL reconstruction, which became the gold standard for surgical ACL treatment in the \ub480s of the last century. Given the limitations and risks associated with the current gold standard treatment of an ACL rupture, there is room for improvement. Modern ACL repair has theoretically several advantages compared to ACL reconstruction. Modern ACL repair techniques are less invasive and there is no graft harvesting morbidity. Preservation of the native ACL ligament and its proprioceptors contributes in the feedback on position and dynamic stability of the knee, which could reduce the rehabilitation period and decrease the risk of post-traumatic osteoarthritis. Due to the high failure risk of open ACL repair in the past, the orthopedic community is reluctant to start with ACL repair. Data on the modern ACL repair techniques will have to show if the theoretical advantages can be proven in daily practice or if history will repeat itself. Novel ACL repair techniques have been introduced this last decade. The aim of this PhD is to contribute to the discussion if these novel repair techniques could be a treatment option for the acute proximal ACL rupture. If a surgeon would like to start with a new technique, the surgeon prepares him or herself by getting familiar with the surgical technique. In this thesis, the suture tape augmentation (STA) surgical technique is described in detail (Chapter 2). Drawings, pictures and a video have been made to explain the surgical technique, step by step. The indication for STA ACL repair and the rehabilitation protocol as well as the advantages, disadvantages, including the limitations are given. Chapter 2 could contribute in the knowledge of STA ACL repair surgical technique. ACL repair data on the STA ACL repair technique was and still is not extensive. Only one case series of 68 patients with one year follow-up, treated by the developer of the STA technique, was published in 2015. In chapter 3 the results of 42 patients who have been treated by the developer of the STA technique are described. This is the first case series with a 2-year follow-up of the STA ACL repair technique. Several patient reported outcome measures (PROMs) showed a meaningful and or significant improvement (KOOS sport and recreation change, VAS-pain and VR-12 physical scores) in comparison to pre-operative. The Marx activity scale demonstrated a significant decrease in comparison to pre-operative. Two of the 42 patients (4.8%) reported an ACL re\u2011rupture. The conclusion of this study is that repair with the STA technique could be clinically relevant as a treatment option for patients with an acute, proximal ACL rupture which is not retracted and of good tissue quality. Chapter 4 reports on our own data of 35 patients who have been treated with the STA ACL repair technique at the Antwerp University hospital. This is the first prospective case-series with independent data of the STA ACL repair on adults. The clinical results, re-rupture risk factors and magnetic resonance imaging (MRI) outcomes with a 2-year follow-up after STA ACL repair are reported. This case series shows that STA ACL repair leads to a stable knee, favorable patient-reported outcome measures (PROMs) and quick rehabilitation after surgery, with a median return to work (RTW) period of 5.5 weeks and a return to sports (RTS) period of 6 months. The re-rupture risk is 11.4% and the re-surgery for another reason than re-rupture is 8.6%. A pre-operative Tegner score (activity score) of 65 7 was associated with a higher risk on re-rupture. Another significant association was observed between the grade of ACL healing on MRI six months post-operatively and re-rupture (P = .006). When analyzing the effect of age (< 25 versus 65 25) on re-rupture, a trend towards significance was observed (P = .061). This study shows that treatment of the acute, repairable ACL with the STA technique leads to a stable knee and favorable PROMs. However, the re-rupture risk of 11% within the 2-year follow-up is a concern. A different ACL repair technique is the dynamic intraligamentary stabilization (DIS) technique. In contrast with the STA technique, the internal brace of the DIS system is dynamic due to the distal fixation in a spring-screw system. This should lead to a more biomechanically stable environment of the knee. The manufacturer of the DIS system advices to repair the ACL within 3 weeks after the rupture, whereas for the STA technique the advised maximum is 3 months. For ACL reconstruction there is no time limit. This changes the management of the ruptured ACL for the DIS technique in a semi-acute trauma. In chapter 5, our experience with the first DIS ACL repairs at the Antwerp University Hospital is described. Starting a new technique involves \u2018start-up problems\u2019. Organizing a new patient pathway to treat the patients within 3 weeks after the trauma, dealing with \u2018new\u2019 arthroscopic instruments and suture management, post-operative problems and MRI interpretation after ACL repair are examples of the issues we encountered. In two years, 15 patients have been treated with this novel ACL repair technique. From the beginning we meticulously recorded the pre-operative, intra-operative and post-operative problems and our solutions. Tips and tricks that could assist surgeons who are starting with the DIS technique are shared. MRI can be used to evaluate the (repaired) ACL. It is important for the radiologist and orthopedic surgeon to get familiar with the normal MRI appearance of ACL healing after repair, and its potential complications in order to avoid misinterpretation and subsequent unnecessary or delayed surgical intervention. In chapter 6, we have described the normal appearance of the repaired ACL on MRI as well as the possible complications of these techniques. The healing process of the repaired ACL is different compared to ACL reconstruction, without the \u201cligamentization\u201d phase. Although patients may demonstrate signs of ACL healing on MRI following repair, absence of healing on MRI within the repair can be seen for more than 12 months postoperatively in some patients with clinically stable knees. MRIs after ACL repair should therefore be interpreted with caution, and correlation with clinical findings is necessary. Multiple reviews on ACL repair have been written on a relatively small amount of case\u2011series the last few years. All these reviews conclude that there is an urge for more data on ACL repair. Long-term follow-up and especially randomized controlled trials between ACL reconstruction, the gold standard and the new ACL repair techniques as well as between the different ACL repair techniques are needed. In 2017, the application for the LIBR\u18e study, a multi-center prospective RCT comparing DIS, STA and reconstruction in individuals with an acute ACL rupture was granted by the FWO (Research Foundation Flanders) for the TBM (Applied Biomedical Research with a Primary Social finality) project. With the author as principal investigator, the study started in 2018. The protocol of the LIBR\u18e study has been published (Chapter 7). The validated PROMS, clinical, proprioceptive and isokinetic measurements and MRI to determine the clinical efficacy of two alternative techniques, DIS and IBLA, in comparison to the conventional ACL reconstruction for treating an acute ACL rupture will supply a large data pool in which several different aspects of ACL repair versus reconstruction can be compared. The LIBR\u18e study is being conducted and could lead to a better comparison between the DIS and STA ACL repair techniques and the gold standard ACL reconstruction. Four different ACL repair techniques have dominated the ACL repair discussion. In chapter 8, a narrative review and critical appraisal of the four different ACL repair techniques, studies by the developers and the early adaptors and the present status is given. After promising short- to mid\u2011term results by the developers, the results of the early adaptors show more variety in terms of re-rupture and re-surgery for other reasons, which led to a more varicolored discussion. Risk factors for failure are described. There is a call for more clinical data and RCTs. Future research could include conservative management versus ACL repair and reconstruction, as well as the risk on osteoarthritis. ACL repair combined with an anterolateral extra-articular procedure could reduce the re-rupture risk, which could be interesting especially for the high-risk groups. One of the most important findings of the last decade is that the ACL is able to heal and subsequently stabilize the knee again. Patient selection is emphasized: the ideal patient is a non-high athlete older than 25 years with an acute proximal ACL rupture. Further research will have to show if ACL repair could be a game changer or if history will repeat itself. In conclusion: this thesis \u201cAn Introduction to Modern Anterior Cruciate Ligament Repair\u201d contributes to the discussion whether these novel repair techniques could be a treatment option for the acute proximal ACL rupture. The ability of the ACL to heal and subsequently re-stabilize the knee with the DIS and the STA repair techniques is confirmed. A step by step description of the ACL STA surgical technique is presented. Our first results and tips and tricks for the DIS repair technique are shared. The healing of the ACL can be monitored with MRI, but correlation with clinical findings is necessary. Based on the two case-series on acute ACL repair with the STA technique it seems that this technique could be clinically relevant as a treatment option for patients with an acute, proximal ACL rupture. A careful patient selection is advised. To reduce the risk on a re-rupture, the ideal patient would be a non-high athlete (Tegner score of < 7) and older than 25 years with an acute proximal ACL rupture of good tissue quality which is not retracted. The call for more data on ACL repair, especially RCTs, is underwritten in the LIBR\u18e study protocol and considerations for the future of ACL repair research are given
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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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