The method for measurement of three-dimensional angle of scoliosis from standard radiographs

Author(s):  
P Glowka ◽  
W Politarczyk ◽  
P Janusz ◽  
L Wozniak ◽  
T Kotwicki
2017 ◽  
Vol 2 (3) ◽  
pp. 2473011417S0000
Author(s):  
Bradley Campbell ◽  
Stephen Conti

Category: Basic Sciences/Biologics, Bunion, Midfoot/Forefoot Introduction/Purpose: The progression of the hallux valgus (HV) deformity demonstrates dorsiflexion and abduction; concomitant pronation has not received adequate documentation and the extent of pronation in the pathology is unknown even though correction of the deformity may need to address all three angles. To overcome the inability of standard radiographs to capture pronation, we have developed a means to assess the three dimensional deformity using CT scans. Our goal was to document the extent of pronation/supination both of the first phalanx with respect to the first metatarsal and of the first metatarsal with respect to the second metatarsal. Furthermore, we wanted to regress pronation against the intermetatarsal (IMA) angle of hallux valgus patients. Methods: Three-dimensional models were reconstructed from loaded and unloaded CT files of patients (10 HV, 10 normal). The orientations of specific bones, in anatomic directions, were determined by selecting landmarks on the surface of the phalanx and of the first and second metatarsals. The resulting calculations output a set of angles to determine the pronation/supination of the first metatarsal relative to the second and of the first phalanx relative to the first metatarsal. A regression analysis was conducted to extrapolate any relationship between adduction and pronation (known intermetatarsal and pronation). Results: The average pronation of the first metatarsal relative to the second metatarsal was 19.8 ± 7.1 and 28.3 ± 10.8 in the normal and HV groups respectively (p < 0.05). The influence of weightbearing demonstrated pronation angle differences that were greater in the normal group than in the HV group for both the IM pronation and the HV pronation (p < 0.05) (Figure 1). The differences in HV angles and IM angles between normal and HV patients were 22° and 7° respectively. The regression analysis of the pronation and intermetatarsal angle was not found to be significant, with a weak correlation (r2 = 0.26). Conclusion: The pronation of the first metatarsal relative to the second metatarsal between normal and HV patients is significantly different. While the first metatarsal had measurable pronation in patients with hallux valgus but that value was not predicted by the IMA. The findings of this study indicate pronation should be considered in any surgical technique that seeks to restore native configurations.


1992 ◽  
Vol 29 (4) ◽  
pp. 363-368 ◽  
Author(s):  
Peter D. Witt ◽  
Robert A. Hardesty ◽  
Craig Zuppan ◽  
Glenn Rouse ◽  
Anton N. Hasso ◽  
...  

The kleeblattschädel deformity is a rare craniofacial condition typified by its trilobed, cloverleaf skull. The pathophysiology of this process is controversial. The morphologic, radiographic, and histologic abnormalities identified in the cranial base of an 18-gestational-week fetus with kleeblattschädel skull have not been described previously. Recently, the intrauterine diagnosis of kleeblattschädel was established by serial ultrasonography and, based on this evidence, the fetus was aborted. The fetus was studied extensively. Standard radiographs and high-resolution CT scans were obtained. Three-dimensional, reformatted contour surface images were constructed from the CT scan data. The cranial base was examined grossly, radiographically, and histologically. Histologic microanatomic study concentrated on structures of the mid-sagittal cranial base from the occiput to the mid maxilla. The distorted cranial architecture in kleeblattschädel deformity has, in the past, been attributed largely to the cranial base deformity which secondarily distorts the developing brain. Our study, however, suggests that the calvarium itself may be the primary focus of abnormal events leading to synostosis. The findings in this study seem to be Inconsistent with earlier theories about the abnormal development of craniodysostoses.


2020 ◽  
pp. 20200159
Author(s):  
Connor Puett ◽  
Christina R Inscoe ◽  
Robert L Hilton ◽  
Michael W Regan Anderson ◽  
Lisa Perrone ◽  
...  

Objectives: A practical approach to three-dimensional (3D) intraoral imaging would have many potential applications in clinical dentistry. Stationary intraoral tomosynthesis (sIOT) is an experimental 3D imaging technology that holds promise. The purpose of this study was to explore synthetic radiography as a tool to improve the clinical utility of the images generated by an sIOT scan. Methods: Extracted tooth specimens containing either caries adjacent to restorations (CAR) or vertical root fractures (VRF) were imaged by sIOT and standard dental radiography devices. Qualitative assessments were used to compare the conspicuity of these pathologies in the standard radiographs and in a set of multi-view synthetic radiographs generated from the information collected by sIOT. Results: The sIOT-based synthetic 2D radiographs contained less artefact than the image slices in the reconstructed 3D stack, which is the conventional approach to displaying information from a tomosynthesis scan. As a single sIOT scan can be used to generate synthetic radiographs from multiple viewing angles, the interproximal space was less likely to be obscured in the synthetic images compared to the standard radiograph. Additionally, the multi-view synthetic radiographs can potentially improve the display of CAR and VRFs as compared to a single standard radiograph. Conclusions: This preliminary experience combining synthetic radiography and sIOT in extracted tooth models is encouraging and supports the ongoing study of this promising approach to 3D intraoral imaging with many potential applications.


2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Paweł Główka ◽  
Wojciech Politarczyk ◽  
Piotr Janusz ◽  
Łukasz Woźniak ◽  
Tomasz Kotwicki

2021 ◽  
Vol 73 (3) ◽  
pp. 571-582
Author(s):  
C.R. Andrade ◽  
B.W. Minto ◽  
R.M. Dreibi ◽  
L.M.I. Diogo ◽  
T.A.S.S. Rocha ◽  
...  

ABSTRACT The outcome of total hip arthroplasty (THA) in dogs is directly related to surgical planning. Templating of radiographs prior to THA should help the surgeon anticipate prosthesis size and femoral shape allowing canal fill of the proximal metaphysis by the implant ensuring primary stable fixation. The canal flare index (CFI) obtained from radiograph has been used as a measure of risk of complications for the technique in human beings and dogs. However, standard radiographs only provide limited data for the selection of cementless prostheses and the assessment of their fit within the femoral canal, due to factors like radiographic magnification and femoral rotation. Therefore, three-dimensional evaluation based on computed tomography (CT) may be a better tool for CFI measurement. The aim of this study was to compare anatomical measurement with CFI values obtained from craniocaudal radiography and CT. Craniocaudal radiographs using a horizontal radiographic beam (CR), CT, and anatomical macroscopic measurements (A) were obtained from 45 femurs from 23 canine cadavers. The differences between the values of CFI obtained from radiograph (CFI-R), computed tomography on transverse (CFI- TT) and longitudinal axis (CFI-TL) compared to the CFI obtained from macroscopic measurements - gold standard - (CFI-A), and 95% limits of agreement (LOA) between the values, were evaluated by the Bland-Altman method. Dimensions obtained from CT techniques had a greatest mean difference from anatomical and CFI values were also different (P=0.032). Under the experimental conditions, the craniocaudal radiograph, provided the most accurate measurement of the CFI (mean difference: 0.087 ± 0.42).


1966 ◽  
Vol 25 ◽  
pp. 227-229 ◽  
Author(s):  
D. Brouwer

The paper presents a summary of the results obtained by C. J. Cohen and E. C. Hubbard, who established by numerical integration that a resonance relation exists between the orbits of Neptune and Pluto. The problem may be explored further by approximating the motion of Pluto by that of a particle with negligible mass in the three-dimensional (circular) restricted problem. The mass of Pluto and the eccentricity of Neptune's orbit are ignored in this approximation. Significant features of the problem appear to be the presence of two critical arguments and the possibility that the orbit may be related to a periodic orbit of the third kind.


Author(s):  
M. Boublik ◽  
W. Hellmann ◽  
F. Jenkins

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.


Author(s):  
P.L. Moore

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.


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