Human vertebra

Figure 4.77 Left archetype human vertebra 1, sensor nerves ...

FIGURE 8J Three-dimensional reconstructions of trabecular bone from the (a) bovine proximal tibia, (b) human proximal tibia, (c) human femoral neck, (d) human vertebra. Each volume is 3 X 3 x 1 mm . From Ref. 142.)... 

FIGURE 8.11 Dependence of ultiinaie stress on age for trabecular bone from the human vertebra and femur. For both anatomic sites, strength decreases approximately 10 percent per decade. (Data from Rrfs. 15 and 149.)... 

Kokubo, T Ohtsuki, C Kotani, S Kitsugi T Yamamuro, T. Surface structure of bioactive glass-ceramics A-W implanted into sheep and human vertebra. In Heimke G editor. Bioceramics Vol. 2. Cologne German Ceramic Society 1990 113-120. 

How to Predict the Fractures Initiation Locus in Human Vertebrae Using Quantitative Computed Tomography(QCT) Based Finite Element Method ... 

Keywords— Human Vertebra, Quantitative Computed Tomography, Compressive Failure, Finite Element Method. 

Noninvasive prediction of strength in vertebral bodies can provide valuable information for the assessment of the risk of fracture in human vertebrae [1-6], The aim of this study was to present an effective specimen-specific approach for predicting failure initiation locus in cadaveric vertebrae using a quantitative computed tomography (QCT) voxel-based finite element method (FEM). 

How to Predict the Fractures Initiation Locus in Human Vertebrae... 

Bone is the main source of calcium in the human body. Osteoporosis, decreased calcium salt reserves in the body, has become the most prevalent bone disease in the U.S., being especially prevalent among post-menopausal women (1). Typical signs of this debilitating condition include backache with spasms, wedge fractures of the dorsal and lumbar vertebrae, and hip fractures (2). 

Other nerve structures are also subject to variation. The position in the vertebral column at which the spinal cord terminates varies over three full vertebrae, and no standard terminal position exists. The positions at which various nerves enter the spinal cord likewise vary from individual to individual. About 15 per cent of the population do not have a "direct pyramidal" nerve tract in the spinal cord. Most human beings have 31 pairs of spinal nerves corresponding to 30 vertebrae some, however, have 32 and some 33 pairs, corresponding to 31 and 32 vertebrae, respectively. Most people have two splanchnic nerves (sympathetic nerves to the digestive system), but occasional individuals have three. In some individuals the sciatic nerve is so embedded that it is always fully protected in others, the pathway of the nerve is such that injury is very likely to occur. 

Lancelet is the common name for about 25 species of simple marine animals, which are classified between invertebrates (animals without backbones) and vertebrates (animals, like humans, with backbones). They have a stiff dorsal rod and a notochord, but no vertebrae or heart. Around their mouths, cirri and tentacles move like a bag of nervous worms. They share the same ancestry as amphioxus, as evidenced by their embryonic tongue-barred gill slits. 

The concentrations of uranium in human blood from New York City donors averaged 0.14 mg U/kg in both whole blood and red cells, compared to values ranging from <0.04 to 86 mg U/kg globally (Fiseime and Perry 1985). The median concentrations of uranium in the lungs, liver, kidneys, and vertebra from... 

Cerivastatin caused a significant increase in incomplete ossification of the lumbar center of the vertebrae in rats at an oral dose of 0.72 mg kg Cerivastatin did not cause any anomalies or malformations in rabbits at oral doses up to 0.7 mg kg These doses resulted in plasma levels about six times the human exposure (Cmax free) for rats and three times the human exposure for rabbits (Cmax free) at a human dose of 0.8 mg. Cerivastatin crossed the placenta and was found in fetal liver, gastrointestinal tract, and kidneys when pregnant rats were given a single oral dose of 2 mg kg... 

Figure 1 Anterior view of an anencephalic human fetus. Notice the low-set ears, elevated nose and maxilla, the short neck (due to anomalies of the cervical vertebrae), and the prominent, protruding rudimentary brain. (Reproduced from Marin-Padilla M (1991) Cephalic axial skeletal-neural dysraphic disorders Embryology and pathology. Canadian Journal of Neurological Sciences 8 153-169, with permission.)...

Figure 2 External appearance of various types of human craniorachischisis totalis (total myeloschisis) illustrating the severity of the dysraphic disorders. The first fetus (a) illustrates the severity of the lordosis and the shortness of the axial skeleton which can occur in these disorders. The exposed areas of the central nervous system are totally destroyed. In (b), note the exencephalic brain (termed area cerebrovasculosa). (c, d) Lateral and posterior view. Compare (c) with Figure 1. In (d), the destroyed areas of brain and spinal cord tissues have been removed to show the severity of the malformations of the vertebrae. (Reproduced from Marin-Padilla M (1978) Clinical and experimental rachischisis. In Congenital Malformations of the Spine and Spinal Cord. vol. 32. Handbook of Clinical Neurology. Amsterdam North-Holland, with permission from Elsevier.)...

Oral administration of nonlethal doses of pyridostigmine did not alter male or female reproductive indices. Administration of pyridostigmine bromide also did not result in significant increases in congenital malformations at low and comparable doses to those used therapeutically in humans. At the high dose level, delayed ossification and missing vertebrae were noted in animal studies. 

Stable strontium is ubiquitous in the diet and can be measured in urine, blood and feces by a number of methods outlined in Section 7.1. After exposure, approximately 99% of the absorbed strontium that is retained is found in bone and connective tissues (Schroeder et al. 1972). Normal background levels of strontium were measured by emission spectrography in cadaver tissue from 168 American subjects (Tipton 1981 Tipton and Cook 1963). Average strontium levels in human tissues expressed as ppm ash were as follows rib bone 110 ppm, vertebra 100 ppm, aorta 33 ppm, ileum 25 ppm, duodenum 11 ppm, lung 8.2 ppm, kidney 5.2, heart 2.6 ppm, liver 1.6 ppm. In a small group of adult males, the mean strontium concentration in plasma was 29pg/L (Sutton et al. 1971b). 

The treatment for osteoporotic compression fracture of the vertebrae has been investigated on human cadaver vertebrae with calcium phosphate cement (Ikeuchi et al. 

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