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Background: Anterior cruciate ligament (ACL) rupture is a very common knee injury in the sport active population. There is much debate on which treatment (operative or non-operative) is best for the individual patient. In order to give a more personalized recommendation we aim to evaluate the effectiveness and cost-effectiveness of a treatment algorithm for patients with a complete primary ACL rupture.Methods: The ROTATE-trial is a multicenter, open-labeled cluster randomized controlled trial with superiority design. Randomization will take place on hospital level (n = 10). Patients must meet all the following criteria: aged 18 year or older, with a complete primary ACL rupture (confirmed by MRI and physical examination) and maximum of 6 weeks of non-operative treatment. Exclusion criteria consists of multi ligament trauma indicated for surgical intervention, presence of another disorder that affects the activity level of the lower limb, pregnancy, and insufficient command of the Dutch language. The intervention to be investigated will be an adjusted treatment decision strategy, including an advice from our treatment algorithm. Patient reported outcomes will be conducted at baseline, 3, 6, 12 and 24 months. Physical examination of the knee at baseline, 12 and 24 months. Primary outcome will be function of the knee measured by the International Knee Documentation Committee (IKDC) questionnaire. Secondary outcomes are, among others, the Tegner activity score, the Knee injury and Osteoarthritis Outcome Score (KOOS) and the 9-item Shared Decision Making Questionnaire (SDM-Q-9). Healthcare use, productivity and satisfaction with ((non-)operative) care are also measured by means of questionnaires. In total 230 patients will be included, resulting in 23 patients per hospital.Discussion: The ROTATE study aims to evaluate the effectiveness and cost-effectiveness of a treatment algorithm for patients with a complete primary ACL rupture compared to current used treatment strategy. Using a treatment algorithm might give the much-wanted personalized treatment recommendation.Trial Registration: This study is approved by the Medical Research Ethics Committee of Erasmus Medical Center in Rotterdam and prospectively registered at the Dutch Trial Registry on May 13th, 2020. Registration number: NL8637. [ABSTRACT FROM AUTHOR]

Purpose: "Biologic therapies" in the field of orthopaedic surgery and sports medicine, so called orthobiologics, have been gaining significant interest from physicians and patients, with increasing usage over the recent years. The aim of this study is to (1) evaluate the usage of orthobiologics in the Netherlands, (2) to clarify the reasons for the use or non-use of orthobiologics, and (3) the most addressed disease for use of orthobiologics. Methods: The authors created a 19-quenstion online survey comprised of both closed-ended and open-ended response questions in order to examine the use of and the indication for orthobiologics. The survey was sent to all the members of the Dutch Orthopaedic Association and Netherlands Association of Sports Medicine of which 15% responded. Results: The majority of the 265 respondents (65%) did not treat patients with or refer patients for treatment with orthobiologics. The most important reasons for not using orthobiologics were the lack of scientific evidence, the lack of good experience, and the lack of insurance coverage. Of the physicians that used orthobiologics, the most used hyaluronic acid (76%) and platelet-rich plasma (27%). Orthobiologics were most used for knee osteoarthritis and medial or lateral epicondylitis. Conclusion: Although some orthobiologic treatments might be effective and the research interest is growing, our study shows that the majority of orthopaedic and sport physician clinicians in the Netherlands still does not make use of orthobiologics as a treatment option, but almost a third of them is contemplating to start using orthobiologics. Level of evidence: III. [ABSTRACT FROM AUTHOR]

In this article we describe the deflection due to gravity of a parabolic mirror, supported by an annular shaped elastic foundation. We calculate the deflection by solving the thin plate equation for plates with a non-constant thickness numerically. It will be shown that a central hole in the elastic foundation of a certain diameter will minimize the deflection of the mirror and will result in minimal RMS values. We compare the mirror deflection caused by 18 and 27 axial point support to the deflection of a mirror on an annular shaped elastic foundation. It will be shown that an annular shaped elastic foundation results is much less deflection and smaller RMS values compared to the multiple point axial support for mirrors smaller than 1 m diameter and F# ratios larger than 2. Using this foundation method, mirrors may become thinner which results in lightweight constructions. [ABSTRACT FROM AUTHOR]

The mode of emplacement of the dolerites and their relation with the overlying basalts are revisited in the light of new information provided by a recent resistivity study of the structure of the Karoo basin and augmented by an analysis of age and palaeomagnetic data. The different styles of intrusion from the bottom to the top are explained in terms of anisotropy, lithology and increasing upward bending stresses accompanied by a decrease in overburden thickness. The lowermost zone 3 consisting of flat lying dolerite sills of large extent occurs in well-laminated, homogeneous shales with a high degree of anisotropy. The thick dolerite-rich middle zone 2 extending from the Upper Ecca Subgroup through the Beaufort Group and partially into higher Formations is characterised by the occurrence of large basin structures of dolerite. A model, which assumes a central dyke as source and based on the principle that the propagating magma front always follows the path of least resistance is developed to explain the formation of a basin structure including the steepening and flattening of the rim. The model also explains the variations in shape and size such as are encountered in the field by taking into consideration the structure of the nexus of lenticular sandstones intercalated with shales and mudstones occurring throughout this zone. The dominant style of intrusion of, at least, the upper part of zone 1 that extends from the surface to a depth of about 700 m is that of dykes and steeply dipping sheets. Another striking feature of this zone is its dolerite-poor nature. An analysis of the magnetic polarities of the dolerites and basalts leads to the conclusion that the reversely polarized dolerites, which only occur in zone 1 were the feeders to the outpouring of the basalts. The younger normally polarized dykes that cut through the entire basalt succession are associated with the period of cooling and contraction following the main phase of dolerite intrusion. The implications, aided by well resolved age determinations are that the duration of intrusion of the Karoo magmatic event was short. Finally, the significant increase in both the amount of dolerite and the thickness of the dolerite bearing layer towards the east supports the view of a magma source in that direction. [ABSTRACT FROM AUTHOR]

The resistivity structure of the Karoo Basin has been determined by an extensive programme of some 280 deep electrical soundings (maximum current electrode spacing = 40 km). The very conductive carbon and pyrite- rich Whitehill Formation acts as an electrical basement to deep soundings where it is well developed. Beyond its limit in the east, the electrical basement consists of granites and metamorphic rocks and is highly resistive. Notwithstanding an appreciable difference in resistivity between the sandstone and mudstone components, the sandstones are neither sufficiently massive nor continuous to be detected separately in sounding curves. Exceptions are a few, thick, massive arenaceous turbidite fans occurring under an appreciable cover in the downwarped Karoo Trough, straddling the Lower Beaufort and Upper Ecca Subgroups at the southern extremity of the basin. The average resistivity of the sedimentary pile above the Whitehill Formation increases from north to south by more than an order of magnitude substantiating geological evidence of a sympathetic increase in diagenesis and metamorphosis. The Karoo Supergroup comprises one of the rare instances of a sedimentry basin where dolerite intrusions occur interbedded with sediments. The very high resistivity contrast between the resistive dolerite and the conductive sediment, results in an exceptionally high degree of electrical anisotropy. This feature has provided a unique opportunity to study the configuration of the network of dolerite intrusions in the sedimentary succession but simultaneously has often seriously restricted the depth of investigation. Previous geological investigations have demonstrated a tri-zonal vertical variation in intrusive style. The resistivity study has shown that elements in each of these zones have their own specific geophysical signature. The largest portion of the basal zone 3 with its flat lying dolerite sills of great lateral extent is confined to well-laminated, homogeneous shales with a high degree of anisotropy in the Lower Ecca Subgroup and is characterized by a low transverse resistance on sounding curves corresponding to a concomitant low content of dolerite. The onset of zone 2, which coincides with the appearance of the first sandstones in the Waterford Formation, is accompanied by a dramatic increase in transverse resistance and hence the amount of dolerite. This dolerite-rich zone, which continues through the Beaufort Group and partially into the higher Formations is characterised by a multitude of basin structures. The variation in structure of the network of dolerites correlates with that of the nexus of lenticular sandstones intercalated with shales and mudstones. Detailed investigations, such as the one in the De Aar area, show that the average percentage of dolerite in the dolerite bearing layer of zone 2 is 45% with a high of 85% and a low of about 10%. Regionally, zone 2 thins to the south but thickens to the east by a factor of at least 5, at the expense of zone 3. The thickening is associated with a lateral increase in the amount of dolerite. Towards the upper portion of zone 2 there is a lower concentration of intrusions and a trend towards smaller basin structures in the Molteno, Elliot and Clarens Formations. Arguably, the most important contribution of the resistivity soundings is the conclusive finding that in the uppermost zone 1, which extends from the surface to a depth of about 700 m, the dominant style of intrusion is that of steeply dipping sheets and vertical dykes and that the zone is especially dolerite-poor with the amount of dolerite only making up about 0.5% or less of the sediments. The nature of zone 1 is independent of the lithology and is due to the decrease of overburden pressure. [ABSTRACT FROM AUTHOR]

Background: Surgical or medical castration and antiestrogenic treatment with tamoxifen are common endocrine treatments for premenopausal women with breast cancer. However, tamoxifen therapy induces high levels of plasma estradiol, with unknown long-term effects. In this study, we investigated the effect of combining estrogen suppression with the luteinizing hormone-releasing hormone agonist buserelin and estradiol receptor blockade with tamoxifen to determine whether the high estradiol levels induced by tamoxifen could be reduced and whether the antitumor effects would be better.Methods: In a three-arm, randomized, prospective trial, from 1988 through 1995, a total of 161 premenopausal patients with advanced breast cancer were randomly assigned to treatment with buserelin, tamoxifen, or both. Patients with steroid receptor-negative tumors or with tumors of unknown receptor status who had a disease-free interval of less than 2 years were excluded. The median follow-up was 7.3 years, during which 76% of the patients died, all of breast cancer. Patient and tumor characteristics were well balanced among treatment groups. All P values are from two-sided tests.Results: Combined treatment with buserelin and tamoxifen was superior to treatment with buserelin or tamoxifen alone by objective response rate (48%, 34%, and 28% of patients who could be evaluated, respectively; P =.11 [chi(2) test]), median progression-free survival (9.7 months, 6.3 months, and 5.6 months; P =.03), and overall survival (3.7 years, 2.5 years, and 2.9 years; P =.01). Actuarial 5-year survival percentages were 34.2% (95% confidence interval [CI] = 20.4%-48.0%), 14.9% (95% CI = 3.9%-25.9%), and 18.4% (95% CI = 7.0%-29.8%), respectively. No differences in antitumor effects were observed between single-agent treatment groups. During combined treatment or treatment with buserelin alone, plasma estradiol levels were suppressed equally; in contrast, during treatment with tamoxifen alone, plasma estradiol levels increased threefold to fourfold over pretreatment levels.Conclusion: Combined treatment with buserelin and tamoxifen was more effective and resulted in longer overall survival than treatment with either drug alone. [ABSTRACT FROM AUTHOR]

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