Effect of loading rate on endplate and vertebral body strength in human lumbar vertebrae

2003 ◽  
Vol 36 (12) ◽  
pp. 1875-1881 ◽  
Author(s):  
Ruth S Ochia ◽  
Allan F Tencer ◽  
Randal P Ching
2020 ◽  
Author(s):  
Romeo Ioan Chira ◽  
Alina Florea ◽  
Vlad Ichim ◽  
Liliana Rogojan ◽  
Alexandra Chira ◽  
...  

Aims: Vertebral lesions, either primary or more frequently metastasis, are difficult targets for percutaneous guided biopsies and surgical biopsies and are associated with greater risks of complications. We investigated the feasibility of endoscopic ultrasound (EUS) fine needle aspiration (FNA) biopsy in the assessment of vertebral osteolytic tumors as an alternative to CT guided biopsy which is the technique currently used.Material and methods: Four patients with osteolytic tumors of the vertebral bodies identified by imaging methods (CT or MRI) – 3 patients, and one with a tumor detected primarily during EUS procedure were included in order to evaluate the feasibility of the procedure. The lesions were located either at the dorsal or lumbar vertebrae. In all cases we performed EUS FNA of the osteolytic vertebral body lesions with 22G needles using the transesophageal or transgastric approach.Results: In all cases EUS FNA provided enough tissue for an accurate histopathological report, with no procedural complication. We diagnosed lung adenocarcinoma, hepatocarcinoma and a pancreatic adenocarcinoma vertebral metastasis and one case of lymphoma.Conclusions: EUS FNA is a valuable technique which should be considered in selected cases, when a “traditional approach” is not applicable or associated with a higher risk. Treatment guidelines are based on the histology of the tumor, histopathological examination being nowadays mandatory. Therefore, we propose for selected cases a feasible technique, with significantly lower procedural risks, as an alternative for open surgical biopsies or computed tomography guided biopsies


2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Asen Kamenov ◽  
Stoyanka Georgieva ◽  
Dobrina Mlachkova ◽  
Daniela Valentinova Monova

Abstract Background and Aims In patients with chronic kidney disease (CKD), arterial calcification (AC) is a potential mechanism for the progression of cardiovascular disease. AC is common in CKD patients and is a consequence of mineral-bone disorders. Indirect anticoagulants or vitamin K deficiency lead to matrix γ-carboxyglutamate decarboxylation, which may potentiate vascular calcification formation. The impaired renal function and indirect anticoagulants intake may lead to vitamin K deficiency and increased AC. The aim of this study is to determine if oral intake of Acenocoumarol has influence on abdominal aorta calcium score (AACS) and the AC relation with atrial fibrillation (AF) and / or ischemic heart disease (IHD) morbidity. Method We observe 129 patients with CKD (glomerular filtration rate below 44 ml/min/1,73 m2, MDRD formula calculated). X - ray of the lateral abdominal aorta is performed for the AACS assessment according to L. I. Kauppila et al. method. The assessment of calcium score is formed by the involvement grade of each segment on the anterior and posterior wall of the vessel along the first four lumbar vertebrae. Calcification affecting less than 1/3 of the anterior wall of the aorta along the lumbar vertebral body receives 1 score and calcification extending over ½ of the vertebral body length receives 3 scores (total score - 24). The patients are distributed into three groups: I group with calcium score from 0 to 7, II - from 8 to 15 and III group - from 16 to 24. The data from assessed AACS are compared with Acenocoumarol intake and the presence/absence of AF and/or IHD. The results are processed with χ2 statistical analysis. Results One hundred twenty nine patients with CKD (95 males and 34 females) are included in the study. The patients data (mean, percentages, degrees, etc.) are summarized in tabl.1 and tabl. 2. Clinically significant is the correlation between the grades of AACS and Acenocoumarol intake (p < 0,05). With the calcium score increasing, the patients percentage treated with Acenocoumarol also increases (fig. 1). There is a moderate correlation (Cramer’s coefficient is 0,39) between the AACS grades and heart morbidity from AF and / or IHD (p < 0,05). The data shows that the higher calcium score is related with increased patients percentage with AF and / or IHD morbidity (fig. 2). In our study, vascular calcifications are found in the abdominal aorta walls in all of the observed patients. We found that a higher AACS is associated with an Acenocoumarol intake in CKD patients and corresponds to an increased morbidity of AF and / or IHD. Acenocoumarol intake may lead to increased AACS. The higher calcium score is associated with a higher incidence of AF and / or IHD morbidity. Conclusion The study outcome supported the hypothesis that the increased AC formation and cardiovascular morbidity high risk could be a reason for the limited vitamin K antagonists (acenocoumarol) use in CKD patients. Furthermore, vitamin K2 supplementation is reasonable and may reduce the progression of AC.


2009 ◽  
Vol 24 (10) ◽  
pp. 1672-1680 ◽  
Author(s):  
Christian Graeff ◽  
Yan Chevalier ◽  
Mathieu Charlebois ◽  
Peter Varga ◽  
Dieter Pahr ◽  
...  

Spine ◽  
1998 ◽  
Vol 23 (8) ◽  
pp. 899-907 ◽  
Author(s):  
Cari M. Whyne ◽  
Serena S. Hu ◽  
Stephen Klisch ◽  
Jeffrey C. Lotz

2017 ◽  
Vol 11 (4) ◽  
pp. 285-292 ◽  
Author(s):  
Oleg Ardatov ◽  
Algirdas Maknickas ◽  
Vidmantas Alekna ◽  
Marija Tamulaitienė ◽  
Rimantas Kačianauskas

AbstractOsteoporosis causes the bone mass loss and increased fracture risk. This paper presents the modelling of osteoporotic human lumbar vertebrae L1 by employing finite elements method (FEM). The isolated inhomogeneous vertebral body is composed by cortical out-er shell and cancellous bone. The level of osteoporotic contribution is characterised by reducing the thickness of cortical shell and elasticity modulus of cancellous bone using power-law dependence with apparent density. The strength parameters are evaluated on the basis of von Mises-Hencky yield criterion. Parametric study of osteoporotic degradation contains the static and nonlinear dynamic analysis of stresses that occur due to physiological load. Results of our investigation are presented in terms of nonlinear interdependence between stress and external load.


2017 ◽  
Vol 7 (6) ◽  
pp. 567-571 ◽  
Author(s):  
Eric A. Hohn ◽  
Bryant Chu ◽  
Audrey Martin ◽  
Elizabeth Yu ◽  
Connor Telles ◽  
...  

Study Design: Cadaver study. Objective: To determine the bone density of lumbar vertebral anatomic subregions. Bone mineral density (BMD) is a major factor in osseous fixation construct strength. The standard region for implant fixation of the spine is the pedicle; however, other regions may be more viable options with higher bone quality. Methods: Using computed tomography images, the spine was digitally isolated by applying a filter for adult bone. The spine model was separated into 5 lumbar vertebrae, followed by segmentation of each vertebra into 7 regions and determination of average Hounsfield units (HU). HU was converted to BMD with calibration phantoms of known BMD. Results: Overall mean BMD in vertebral regions ranged from 172 to 393 mg/cm3 with the highest and lowest BMD in the lamina and vertebral body, respectively. Vertebral regions formed 3 distinct groups ( P < .03). The vertebral body and transverse processes represent one group with significantly lower BMD than other regions. Spinous process, pedicles, and superior articular processes represent a second group with moderate BMD. Finally, inferior articular process (IAP) and lamina represent a third group with significantly higher BMD than other regions. Conclusions: Standard lumbar fusion currently uses the vertebral body and pedicles as primary locations for fixation despite their relatively low BMD. Utilization of posterior elements, especially the lamina and IAP, may be advantageous as a supplement to modern constructs or the primary site for fixation, possibly mitigating construct failures due to loosening or pullout.


2005 ◽  
Vol 5 (4) ◽  
pp. S114-S115
Author(s):  
Kimihiko Sawakami ◽  
Alexander G. Robling ◽  
Minrong Ai ◽  
Matthew L. Warman ◽  
Charles H. Turner
Keyword(s):  

2012 ◽  
Vol 93 (1) ◽  
pp. 44-48
Author(s):  
A B Tomilov ◽  
N L Kuznetsova

Aim. To improve the results of treatment of patients with post-traumatic deformity of the vertebral column. Methods. Analyzed were the results of treatment of 400 patients with fractures of the thoracic and lumbar vertebrae. Lesions of types A2, A3 and B according to the classification of the Association of osteosynthesis were seen in 70% of cases, lesions of type C - in 30%. The external transpedicular «Crab» construction was used in 100 patients. An internal transpedicular construction of the Scientific Research Institute «Syntez» was used in 300 cases. Transpedicular spondylosynthesis with intraoperative correction of the deformity with an original repositioning device was performed in all patients. Explosion fractures with the destruction of the vertebral body and stenosis of the spinal canal demanded the implementation of decompressive-stabilizing interventions in 25% of the cases. Conducted were clinical and radiological (spondylography, computed tomography, magnetic resonance imaging) studies. Results. Proposed was a technique of guided correction of posttraumatic deformities of the vertebral column. Unstable fractures and dislocation-fractures, lesions of intervertebral discs in the thoracic and lumbar segments of the vertebral column, inveterate lesions, posttraumatic deformities of the thoracic and lumbar segments of the vertebral column served as indications for using guided correction. Kyphotic deformity at the level of the damaged segment was corrected in 98% of observed cases with hypercorrection in the range of 2°. The vertical size of the vertebral body was restored up to 100% in the early posttraumatic period and up to 82.3% in the remote posttraumatic period. Subluxation was corrected in 86.9%, while dislocation of the fractured vertebra was corrected in 96.7% of cases. Conclusion. The proposed method of correction of posttraumatic deformities of the vertebral column makes it possible to provide similar treatment results of patients operated both with using the external fixation device of the vertebral column «Crab» and using the submersible transpedicular construction of the Scientific Research Institute «Syntez».


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