Calcaneal Fractures: Three-dimensional Treatment

Foot & Ankle ◽  
1988 ◽  
Vol 8 (4) ◽  
pp. 180-197 ◽  
Author(s):  
Michael M. Romash

A series of 22 calcaneal fractures operated over 4 yr is presented. Radiographic evaluation of these fractures using axial, lateral, anteroposterior, and oblique medial projection (Broden's view) with varying tube angulation toward the head and computerized axial tomography in two planes, coronal and transverse, were done. This repeatedly demonstrated intra-articular splitting fractures along the axis of the os calcis through the posterior facet, extending to the calcaneocuboid joint. These fractures were surgically reduced as described by McReynolds with sequential medial and lateral approaches. Intraoperative X-rays demonstrate the three-dimensional nature of this injury. Bohler's angle may be reconstituted with apparent reduction of the posterior facet when projected laterally; however, Broden's and axial views show persistent widening and split of the posterior facet. The 22 patients have been followed from 12 to 46 mo. All have heels of normal width and wear standard shoes. The first two cases, done only medially, have less than anatomic reconstruction of the subtalar joint. Functional results have been encouraging. Of six active duty members so treated, three returned to full duty, a second who was medically retired as a result of other injuries had minimal heel problems, and fifth had a contralateral open pilon fracture which hampers him, and the sixth patient is now 4 mo postbilateral calcaneal fractures with return to duty anticipated. Most of the 22 have some decrease in subtalar motion without apparent gait abnormality. No cases of medial or lateral impingement or tendinitis are present. Fractures of the calcaneus are amendable to open reduction and internal fixation. Sequential medial and anterolateral exposure allow anatomic reconstruction in three dimensions, avoiding pitfalls of two-dimensional analysis and treatment.

Author(s):  
David Blow

Diffraction refers to the effects observed when light is scattered into directions other than the original direction of the light, without change of wavelength. An X-ray photon may interact with an electron and set the electron oscillating with the X-ray frequency. The oscillating electron may radiate an X-ray photon of the same wavelength, in a random direction, when it returns to its unexcited state. Other processes may also occur, akin to fluorescence, which emit X-rays of longer wavelengths, but these processes do not give diffraction effects. Just as we see a red card because red light is scattered off the card into our eyes, objects are observed with X-rays because an illuminating X-ray beam is scattered into the X-ray detector. Our eye can analyse details of the card because its lens forms an image on the retina. Since no X-ray lens is available, the scattered X-ray beam cannot be converted directly into an image. Indirect computational procedures have to be used instead. X-rays are penetrating radiation, and can be scattered from electrons throughout the whole scattering object, while light only shows the external shape of an opaque object like a red card. This allows X-rays to provide a truly three-dimensional image. When X-rays pass near an atom, only a tiny fraction of them is scattered: most of the X-rays pass further into the object, and usually most of them come straight out the other side of the whole object. In forming an image, these ‘straight through’ X-rays tell us nothing about the structure, and they are usually captured by a beam stop and ignored. This chapter begins by explaining that the diffraction of light or X-rays can provide a precise physical realization of Fourier’s method of analysing a regularly repeating function. This method may be used to study regularly repeating distributions of scattering material. Beginning in one dimension, examples will be used to bring out some fundamental features of diffraction analysis. Graphic examples of two-dimensional diffraction provide further demonstrations. Although the analysis in three dimensions depends on exactly the same principles, diffraction by a three-dimensional crystal raises additional complications.


2021 ◽  
pp. 40-43
Author(s):  
Nirottam Singh ◽  
Jagdish Jagdish ◽  
Hemant Jain ◽  
Kishore Raichandani

Objective: Calcaneal fractures are caused by a high velocity force to the heel, mostly in road trafc accidents or fall from height. Debate continues regarding the best management of calcaneal fractures. We aim at evaluating the radiological and functional outcomes of displaced intra-articular calcaneal fractures treated with Ilizarov ring xation. Methods: intra-articular calcaneal Eighteen consecutive patients with fractures [Sanders type II (10), Sanders type III(6), and Sanders type IV (2)] were treated with the Ilizarov ring xator from Sep 2017 to June 2020. Patients were evaluated in terms of associated injuries and x-rays of anteroposterior, lateral and axial views of the calcaneus. CT scan was done to assess the amount of comminution and articular depression. Patients were followed up clinically and radiologically at least for 1 year. Functional outcome was assessed using the American Orthopaedics Foot and Ankle Society (AOFAS) scale. Radiological assessment was done by Bohler's angle and Gissane's angle along with measurement of calcaneal height and width. Results: At average follow-up of 18.5 months, average AOFAS score was 80.5 (range 71 to 90), with 6.25% having excellent, 75% having good, 12.5% having fair and 6.25%having poor results. All patients had stable ankle joint with all having dorsiexion and plantar exion more than 30°. All patients are able to wear their previous size shoes. The mean Bohler's angle, mean Gissane's angle, calcaneal height and width were 21.5°, 126.3°, 4.36 cm and 3.80cm respectively at nal follow-up. Four patients had supercial pin tract infection. One patient had collapse of posterior facet after removal of xator with peroneal tendinitis. All fractures united and none needed secondary bone grafting. Patients returned to work on an average of 5.5 months. Conclusion: Ilizarov external ring xation gives good functional outcomes, manifested by restoring near normal anatomic reconstruction of morphology and alignment of the calcaneus. The added advantages of these procedures are the considerably shortened operating time and hospital stay, no need of highly equipped operation theatres and the reduced risk of complications related to surgical exposure.


2019 ◽  
Vol 43 (12) ◽  
pp. 2839-2847 ◽  
Author(s):  
Antoine Fourgeaux ◽  
John Estens ◽  
Thierry Fabre ◽  
Olivier Laffenetre ◽  
Julien Lucas y Hernandez

2005 ◽  
Vol 38 (01) ◽  
pp. 18-21
Author(s):  
C Alfano ◽  
Paolo Mezzana ◽  
N Scuderi

ABSTRACTSince 1970, as computed axial tomography machines became easily available and became more sophisticated, image acquisition techniques and analysis improved, developed rapidly and became very useful in medical diagnosis. Today it is possible to examine either the anatomic and functional aspects of deep body organs and tissues including all the minute details as well as their morphological relations with superficial structures. Through precise graphic elaboration programs we can obtain information about spatial relations which was not possible using simply classical clinical examination. It is possible, for example, to "point out" an area of interest from its anatomic context, to carry out virtual cleavage of planes and to measure volumes and distances. New developments in image acquisition systems permit transfer of three-dimensional data directly from existing objects. The three -dimensional computerized axial tomography for deep structures, and the laser scanners for superficial structure, quickly furnish (1-3 seconds for the laser scanners) useful information to plan the surgical operation.When analysing 3D-imaging techniques it is important to appreciate their utility for the planning and the follow up of surgery, particularly for the head and thorax, where the three dimensional evaluation is better than the classic double dimensional system that is incomplete and difficult to interpret. In the future, these systems will be important for the best aesthetic and functional results and above all for reducing the surgical time.


2016 ◽  
Vol 23 (5) ◽  
pp. 1241-1244 ◽  
Author(s):  
Wonsuk Cha ◽  
Wenjun Liu ◽  
Ross Harder ◽  
Ruqing Xu ◽  
Paul H. Fuoss ◽  
...  

A method is presented to simplify Bragg coherent X-ray diffraction imaging studies of complex heterogeneous crystalline materials with a two-stage screening/imaging process that utilizes polychromatic and monochromatic coherent X-rays and is compatible within situsample environments. Coherent white-beam diffraction is used to identify an individual crystal particle or grain that displays desired properties within a larger population. A three-dimensional reciprocal-space map suitable for diffraction imaging is then measured for the Bragg peak of interest using a monochromatic beam energy scan that requires no sample motion, thus simplifyingin situchamber design. This approach was demonstrated with Au nanoparticles and will enable, for example, individual grains in a polycrystalline material of specific orientation to be selected, then imaged in three dimensions while under load.


IUCrJ ◽  
2015 ◽  
Vol 2 (5) ◽  
pp. 575-583 ◽  
Author(s):  
Jose A. Rodriguez ◽  
Rui Xu ◽  
Chien-Chun Chen ◽  
Zhifeng Huang ◽  
Huaidong Jiang ◽  
...  

A structural understanding of whole cells in three dimensions at high spatial resolution remains a significant challenge and, in the case of X-rays, has been limited by radiation damage. By alleviating this limitation, cryogenic coherent diffractive imaging (cryo-CDI) can in principle be used to bridge the important resolution gap between optical and electron microscopy in bio-imaging. Here, the first experimental demonstration of cryo-CDI for quantitative three-dimensional imaging of whole frozen-hydrated cells using 8 keV X-rays is reported. As a proof of principle, a tilt series of 72 diffraction patterns was collected from a frozen-hydratedNeospora caninumcell and the three-dimensional mass density of the cell was reconstructed and quantified based on its natural contrast. This three-dimensional reconstruction reveals the surface and internal morphology of the cell, including its complex polarized sub-cellular structure. It is believed that this work represents an experimental milestone towards routine quantitative three-dimensional imaging of whole cells in their natural state with spatial resolutions in the tens of nanometres.


2013 ◽  
Vol 4 (1) ◽  
pp. 74-76
Author(s):  
Narendra S Sharma ◽  
Pushpa V Hazarey ◽  
RH Kamble ◽  
Preethi N Sharma

ABSTRACT Implant used for skeletal anchorage offers clinical advantage of being smaller in size, ease of insertion and removal, the ability to load forces immediately and rapid healing. The risk of injury to dental roots during placement is one of the greatest concerns with implant especially when they are inserted between teeth. Placement of implant to close to the root can also result in insufficient bone remodeling around the screw and transmission of occlusal forces through the teeth to the screw which can lead to implant failure. Therefore it is important to select insertion site carefully using clinical and radiographic evaluation. Many techniques have been used to facilitate safe placement of implant. Some or the others may be inconsistent in different radiographic view. This article introduces a three-dimensional (3D) wire grid which is simple, reliable and accurate for placing implant in a single step which improves the insertion success rate. How to cite this article Sharma NS, Shrivastav SS, Hazarey PV, Kamble RH, Sharma PN. Universal Wire Grid for Implant Placement in Three Dimensions. World J Dent 2013;4(1): 74-76.


2010 ◽  
Vol 7 (51) ◽  
pp. 1497-1501 ◽  
Author(s):  
K. Grandfield ◽  
E. A. McNally ◽  
A. Palmquist ◽  
G. A. Botton ◽  
P. Thomsen ◽  
...  

A positive interaction between human bone tissue and synthetics is crucial for the success of bone-regenerative materials. A greater understanding of the mechanisms governing bone-bonding is often gained via visualization of the bone–implant interface. Interfaces to bone have long been imaged with light, X-rays and electrons. Most of these techniques, however, only provide low-resolution or two-dimensional information. With the advances in modern day transmission electron microscopy, including new hardware and increased software computational speeds, the high-resolution visualization and analysis of three-dimensional structures is possible via electron tomography. We report, for the first time, a three-dimensional reconstruction of the interface between human bone and a hydroxyapatite implant using Z-contrast electron tomography. Viewing this structure in three dimensions enabled us to observe the nanometre differences in the orientation of hydroxyapatite crystals precipitated on the implant surface in vivo versus those in the collagen matrix of bone. Insight into the morphology of biointerfaces is considerably enhanced with three-dimensional techniques. In this regard, electron tomography may revolutionize the approach to high-resolution biointerface characterization.


Author(s):  
John C. Russ

Three-dimensional (3D) images consisting of arrays of voxels can now be routinely obtained from several different types of microscopes. These include both the transmission and emission modes of the confocal scanning laser microscope (but not its most common reflection mode), the secondary ion mass spectrometer, and computed tomography using electrons, X-rays or other signals. Compared to the traditional use of serial sectioning (which includes sequential polishing of hard materials), these newer techniques eliminate difficulties of alignment of slices, and maintain uniform resolution in the depth direction. However, the resolution in the z-direction may be different from that within each image plane, which makes the voxels non-cubic and creates some difficulties for subsequent analysis.


Author(s):  
J. A. Eades ◽  
A. E. Smith ◽  
D. F. Lynch

It is quite simple (in the transmission electron microscope) to obtain convergent-beam patterns from the surface of a bulk crystal. The beam is focussed onto the surface at near grazing incidence (figure 1) and if the surface is flat the appropriate pattern is obtained in the diffraction plane (figure 2). Such patterns are potentially valuable for the characterization of surfaces just as normal convergent-beam patterns are valuable for the characterization of crystals.There are, however, several important ways in which reflection diffraction from surfaces differs from the more familiar electron diffraction in transmission.GeometryIn reflection diffraction, because of the surface, it is not possible to describe the specimen as periodic in three dimensions, nor is it possible to associate diffraction with a conventional three-dimensional reciprocal lattice.


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