The Role of Locking Plate Stiffness in Bone Fracture Healing Stabilized by Far Cortical Locking Technique

The locking plate fixations have been developed to enhance bone healing by wide bridging of the fracture and allowing some level of interfragmentary movement (IFM) at the fracture site. However, the IFM induced by conventional locking plate constructs is not uniform at the fracture site and so result in asymmetric callus formation, and ultimately delayed healing. The far cortical locking technique has been recently innovated to address this issue by inducing a uniform IFM. However, the far cortical locking technique is still in its infancy and more research efforts are required before its practical clinical application. Using the theory of porous media and computational methods, this study investigated the effectiveness of far cortical locking technique in presence of different mechanical stiffness of locking plate. The research outcomes indicate that the application of far cortical looking technique enhances IFM at near cortex, and so reduce the difference of IFM between near and far cortex. Further, it shows that, under far cortical locking technique, the bending stiffness of a locking plate plays an important role in bone healing. The use of a stiffer locking plate together with far cortical locking screws encourages more uniform tissue development across the fracture gap. The current research underlines the importance of the optimal selection of plate stiffness for application of far cortical locking technique.

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Analysis of low-dose estrogen on callus BMD as measured by pQCT in postmenopausal women

BMC Musculoskeletal Disorders ◽

10.1186/s12891-020-03713-4 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

K. Jäckle ◽

J. P. Kolb ◽

A. F. Schilling ◽

C. Schlickewei ◽

M. Amling ◽

...

Keyword(s):

Bone Density ◽

Beneficial Effect ◽

Fracture Healing ◽

Postmenopausal Women ◽

Bone Healing ◽

Bone Fracture ◽

Low Dose ◽

Callus Formation ◽

Trial Registration ◽

Bone Fracture Healing

Abstract Background Osteoporosis affects elderly patients of both sexes. It is characterized by an increased fracture risk due to defective remodeling of the bone microarchitecture. It affects in particular postmenopausal women due to their decreased levels of estrogen. Preclinical studies with animals demonstrated that loss of estrogen had a negative effect on bone healing and that increasing the estrogen level led to a better bone healing. We asked whether increasing the estrogen level in menopausal patients has a beneficial effect on bone mineral density (BMD) during callus formation after a bone fracture. Methods To investigate whether estrogen has a beneficial effect on callus BMD of postmenopausal patients, we performed a prospective double-blinded randomized study with 76 patients suffering from distal radius fractures. A total of 31 patients (71.13 years ±11.99) were treated with estrogen and 45 patients (75.62 years ±10.47) served as untreated controls. Calculated bone density as well as cortical bone density were determined by peripheral quantitative computed tomography (pQCT) prior to and 6 weeks after the surgery. Comparative measurements were performed at the fractured site and at the corresponding position of the non-fractured arm. Results We found that unlike with preclinical models, bone fracture healing of human patients was not improved in response to estrogen treatment. Furthermore, we observed no dependence between age-dependent bone tissue loss and constant callus formation in the patients. Conclusions Transdermally applied estrogen to postmenopausal women, which results in estrogen levels similar to the systemic level of premenopausal women, has no significant beneficial effect on callus BMD as measured by pQCT, as recently shown in preclinical animal models. Trial registration Low dose estrogen has no significant effect on bone fracture healing measured by pQCT in postmenopausal women, DRKS00019858. Registered 25th November 2019 - Retrospectively registered. Trial registration number DRKS00019858.

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“Mysterious power of harmony...”: lessons of a simulation type in L.V. Shamrey’s scientific and methodological works

Literature at School ◽

10.31862/0130-3414-2020-3-110-118 ◽

2020 ◽

pp. 110-118

Author(s):

L.V. Derbentseva

Keyword(s):

Literary Work ◽

Practical Experience ◽

Literature Teaching ◽

Literary Education ◽

Content Selection ◽

Huge Impact ◽

The Difference ◽

Goals And Objectives ◽

Selection Of

The purpose of the article is to present the scientific and methodological ideas of Professor L.V. Shamrey’s, ScD in Education. The article focuses on the issues of modern lessons of Literature; the issues, related to the general and philological culture of the teacher, their professional skills to plan and structure one’s activities, rethink the goals and objectives of teaching in accordance with modern requirements. The article includes information on the all-Russian conference “Literary work in the context of artistic culture” (Nizhny Novgorod), dedicated to the memory of L.V. Shamrey. The article includes a substantial review of her monograph “The role of image-associative thinking in the development of the school pupil reader”. Describing the scientific direction headed by L.V. Shamrey, the author dwells in detail on the difference between the lessons of a simulation type and traditional literature lessons. The difference entails imagery as a principle of structuring educational activities, increased emotiveness, careful selection of content, higher complexity of tasks and accuracy of wording. In the article special attention is paid to the staged structure and organization of the lessons of a simulation type including the “birth” of an idea expressed in a metaphorical form, concept, principles of content selection, and description of the course of the lesson. Theoretically based ideas are supported by some examples of lessons from the practical experience of L.V. Shamrey’s. By way of conclusion, the author deduces that the introduction of the lessons of a simulation type into the literature teaching process is not a rejection of the traditional classical lesson. It’s an enrichment of the teacher’s professional culture which has a huge impact on the development of literary education in school and a certain degree of students’ freedom of reflection over the read piece of art.

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Aplikasi Qirāāt Sebagai Petunjuk Dalam Tafsir Imam Al-Ṭabari: Kajian Surah Al-Baqarah

QIRAAT: Jurnal Al-Quran dan isi-isu kontemporari ◽

10.53840/qiraat.v4i1.7 ◽

2021 ◽

Vol 4 (1) ◽

pp. 35-46

Author(s):

Mujahid Ahmad Lutfi ◽

Khairul Anuar Mohamad ◽

Mohd Ikram Mohd Nawi ◽

Muhammad Zaid Shamshul Kamar

Keyword(s):

The Difference ◽

Text Study ◽

Selection Of

The difference of qirāāt in the recitation of the Qur'an is a semantic and guide to the mufassirin in the process of interpreting the Qur'an. The process of tafsir al-Quran that has been done by the mufassirin certainly cannot be separated from the discussion about the difference of qirāāt, because its contained in the recitation of al-Quran itself. This paper discusses the role of qirāāt on the side of Imam al-Ṭabari in his tafsir Jāmi ’al Bayān’ An Ta’wīl Āyi al-Quran. This research was conducted through the text of the book based on surah al-Baqarah. The selection of this surah is significant because usually mufassirin make surah al-Baqarah as catalyst and stand in their book, based on the fact that it is the longest surah in the Quran and it is at the beginning after surah al-Fātiḥah. The type of research in this study is a library study and a book text study that has been conducted on tafsir Jāmi ’al-Bayān. The results of the analysis found that Imam al-Ṭabari presented qirāāt as a guide and semantic to the tafsir of the Qur’an. His methodology is based on the criteria of his choices in qiraat used between mutawātirah and syadhdhah, attributing qiraat to those who recite it, the role of tawjīh al-qirāāt in tafsir, and his commentary on the qirāāt mentioned by him.

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What Can We Learn from Planning Instruments in Flood Prevention? Comparative Illustration to Highlight the Challenges of Governance in Europe

Water ◽

10.3390/w12061841 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1841

Author(s):

Mathilde Gralepois

Keyword(s):

Spatial Planning ◽

Flood Management ◽

Prevention Policy ◽

Flood Prevention ◽

Planning Policy ◽

Management Literature ◽

The Difference ◽

Choice Of Instruments ◽

Selection Of

Studying the selection of planning instruments in flood prevention can be critical to gain a better understanding of governance. This choice is underestimated in the flood management literature. This paper fills a knowledge gap in flood management governance by examining the rationales for the choice of instruments. The study is grounded on a comparative illustration of planning instruments in flood prevention in three European countries: England, France and the Netherlands. Flood prevention through spatial planning is a specific example, as the implementation of the Floods Directive has reactivated the role of spatial planning in urban agglomerations. The choice of instruments is never neutral. In the field of flood management, alignment among strategies is supposed to lead to resilience. Instruments should be aligned and coherent. Is that the case? The article explains the challenges of governance configured by a conflict between the spatial planning policy steered by local authorities and the risk prevention policy led by national authorities. This model is further complicated by the tension between the preference for legal, technical or scientific instruments, and the difference in professional culture between planning and prevention. The selection of instrument shows that if their conflicts are exacerbated to debates on variables or parameters, it is because there is no political agreement on the balance between development and security.

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Analysis of low-dose estrogen on callus BMD as measured by pQCT in postmenopausal women

10.21203/rs.3.rs-29939/v3 ◽

2020 ◽

Author(s):

Katharina Blanka Dr. Jäckle ◽

Jan Philipp Kolb ◽

Arndt F Schilling ◽

Carsten Schlickewei ◽

Michael Amling ◽

...

Keyword(s):

Bone Density ◽

Beneficial Effect ◽

Fracture Healing ◽

Postmenopausal Women ◽

Bone Healing ◽

Bone Fracture ◽

Low Dose ◽

Callus Formation ◽

Trial Registration ◽

Bone Fracture Healing

Abstract Background: Osteoporosis affects elderly patients of both sexes. It is characterized by an increased fracture risk due to defective remodeling of the bone microarchitecture. It affects in particular postmenopausal women due to their decreased levels of estrogen. Preclinical studies with animals demonstrated that loss of estrogen had a negative effect on bone healing and that increasing the estrogen level led to a better bone healing. We asked whether increasing the estrogen level in menopausal patients has a beneficial effect on bone mineral density (BMD) during callus formation after a bone fracture.Methods: To investigate whether estrogen has a beneficial effect on callus BMD of postmenopausal patients, we performed a prospective double-blinded randomized study with 76 patients suffering from distal radius fractures. A total of 31 patients (71.13 years ± 11.99) were treated with estrogen and 45 patients (75.62 years ± 10.47) served as untreated controls. Calculated bone density as well as cortical bone density were determined by peripheral quantitative computed tomography (pQCT) prior to and six weeks after the surgery. Comparative measurements were performed at the fractured site and at the corresponding position of the non-fractured arm.Results: We found that unlike with preclinical models, bone fracture healing of human patients was not improved in response to estrogen treatment. Furthermore, we observed no dependence between age-dependent bone tissue loss and constant callus formation in the patients.Conclusions: Transdermally applied estrogen to postmenopausal women, which results in estrogen levels similar to the systemic level of premenopausal women, has no significant beneficial effect on callus BMD as measured by pQCT, as recently shown in preclinical animal models.Trial registration: Low dose estrogen has no significant effect on bone fracture healing measured by pQCT in postmenopausal women, DRKS00019858. Registered 25th November 2019 - Retrospectively registered. Trial registration number DRKS00019858.

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Axial Micromotion Locking Plate Construct Can Promote Faster and Stronger Bone Healing in an Ovine Osteotomy Model

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2020.593448 ◽

2021 ◽

Vol 8 ◽

Author(s):

Zhihua Han ◽

Jianhong Wu ◽

Guoying Deng ◽

Chun Bi ◽

Jiandong Wang ◽

...

Keyword(s):

Bone Healing ◽

Locking Plate ◽

Bone Fractures ◽

Callus Formation ◽

Axial Loading ◽

Axial Loads ◽

Torsional Testing ◽

Bone Callus ◽

Optimal Type

Fixing bone fractures with controlled axial interfragmentary micromotion improves bone healing; however, the optimal type of implant construct for this purpose is still lacking. The present study describes a novel axial micromotion locking plate (AMLP) construct that allows axial interfragmentary micromotion of 0.3 or 0.6 mm. We investigated whether the AMLP constructs enhance bone healing compared to an ordinary locking plate (LP) using an ovine osteotomy model. The stiffness of the constructs was tested under axial loading. We created a 3-mm osteotomy in the left hind leg tibia of sheep that was then stabilized with a 0.3- or 0.6-mm AMLP or LP construct (n = 6/group). Bone healing was monitored weekly by X-ray radiography starting from week 3 after surgery. At week 9, the specimens were collected and evaluated by computed tomography and torsional testing. We found that the AMLPs had a lower stiffness than the LP; in particular, the stiffness of the 0.6-mm AMLP construct was 86 and 41% lower than that of the LP construct for axial loads <200 and >200 N, respectively. In the in vivo experiments, tibial osteotomies treated with the 0.6-mm AMLP construct showed the earliest maximum callus formation (week 5) and the highest volume of bone callus (9.395 ± 1.561 cm3 at week 9). Specimens from this group also withstood a 27% greater torque until failure than those from the LP group (P = 0.0386), with 53% more energy required to induce failure (P = 0.0474). These results demonstrate that AMLP constructs promote faster and stronger bone healing than an overly rigid LP construct. Moreover, better bone healing was achieved with an axial micromotion of 0.6 mm as compared to 0.3 mm.

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The role of differential phase contrast in electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108027 ◽

1978 ◽

Vol 36 (1) ◽

pp. 176-177

Author(s):

E.M. Waddell ◽

J.N. Chapman ◽

R.P. Ferrier

Keyword(s):

Phase Contrast ◽

Practical Method ◽

Position Vector ◽

Differential Phase ◽

Pure Phase ◽

Differential Phase Contrast ◽

The Difference ◽

Image Position ◽

First Moment

Dekkers and de Lang (1977) have discussed a practical method of realising differential phase contrast in a STEM. The method involves taking the difference signal from two semi-circular detectors placed symmetrically about the optic axis and subtending the same angle (2α) at the specimen as that of the cone of illumination. Such a system, or an obvious generalisation of it, namely a quadrant detector, has the characteristic of responding to the gradient of the phase of the specimen transmittance. In this paper we shall compare the performance of this type of system with that of a first moment detector (Waddell et al.1977).For a first moment detector the response function R(k) is of the form R(k) = ck where c is a constant, k is a position vector in the detector plane and the vector nature of R(k)indicates that two signals are produced. This type of system would produce an image signal given bywhere the specimen transmittance is given by a (r) exp (iϕ (r), r is a position vector in object space, ro the position of the probe, ⊛ represents a convolution integral and it has been assumed that we have a coherent probe, with a complex disturbance of the form b(r-ro) exp (iζ (r-ro)). Thus the image signal for a pure phase object imaged in a STEM using a first moment detector is b2 ⊛ ▽ø. Note that this puts no restrictions on the magnitude of the variation of the phase function, but does assume an infinite detector.

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