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To gain insight into the growth- and age-related origins of bone fragility at the proximal femur, we analyzed structural and biomechanical data of the femoral neck from a study of postmenopausal women with hip fractures and their 47 premenopausal daughters. Results were expressed as standard deviations (SD) or Z-scores (mean +/- SEM) adjusted for age and weight, derived using a normal reference population of 262 premenopausal women and 370 postmenopausal women. Women with hip fractures had increased femoral neck (FN) periosteal and endocortical diameters (1.01 +/- 0.26 SD and 1.18 +/- 0.25 SD, respectively). Cortical thickness was reduced by 0.96 +/- 0.1 SD and volumetric bone mineral density (vBMD) was reduced by 1.2 +/- 0.1 SD). The section modulus was normal while the buckling ratio was increased by 1.59 +/- 0.17 SD). Their daughters had increased FN diameter by about one half that of their mothers (0.48 +/- 0.16 SD), while endocortical diameter was increased by only one third (0.44 +/- 0.13 SD). Cortical thickness and vBMD were not reduced, the section modulus was increased (0.48 +/- 0.13 SD) while the buckling ratio was normal. We infer that the larger femoral neck size in women with hip fractures is growth-related; the wider endocortical cavity and thinner cortex is the result of excessive age-related endocortical bone resorption producing a thin cortex in a larger bone predisposing to structural failure by local buckling. The structural basis of bone fragility has some features originating during growth and others during aging.

-The aim of this study was to assess bone mineral density and vitamin D metabolism in patients on chronic anticonvulsant therapy. Methods: Sixty-nine men, outpatients on chronic anticonvulsant therapy, who had been treated for at least 5 years, were studied, comparing them to thirty healthy controls. Bone mineral density was measured as well as serum levels of calcium, ionized calcium, alkaline phosphatase, PTH, 25-hydroxycholecalciferol and 1,25-dihydroxycholecalciferol. Results: No differences in bone mineral density, serum levels of vitamin D and intact-PTH were observed between patients and controls. Bone mineral density was not associated with chronic anticonvulsant therapy. Conclusion: Those adult patients who were on chronic anticonvulsant therapy and who lived in low latitude regions had normal bone mineral density as well as vitamin D serum levels.KEY WORDS: vitamin D, calcium, anticonvulsant, bone mineral density. Densidade mineral óssea, vitamina D e terapia anticonvulsivanteRESUMO -O objetivo deste estudo foi avaliar a densidade mineral óssea e o metabolismo da vitamina D em usuários crônicos de anticonvulsivantes. Métodos: Foram estudados 69 pacientes ambulatoriais, masculinos, usuários crônicos de anticonvulsivantes por período mínimo de 5 anos e comparados a 30 controles normais. Foram efetuadas as medidas da densidade mineral óssea e dos níveis plasmáticos do cálcio, cálcio iônico, fosfatase alcalina, paratormônio, 25-hidroxi-colecalciferol e 1,25-di-hidroxi-colecalciferol. Resultados: Nenhuma diferença na densidade mineral óssea e nos níveis plasmáticos da vitamina D e paratormônio foram observadas entre os pacientes e os controles. A densidade mineral óssea não se mostrou associada ao uso crônico de anticonvulsivantes. Conclusões: Pacientes adultos, do sexo masculino, usuários crônicos de anticonvulsivantes, residentes em regiões ensolaradas, têm densidade mineral óssea e níveis plasmáticos de vitamina D normais. PALAVRAS-CHAVE: vitamina D, cálcio, anticonvulsivante, densidade mineral óssea.Alterations in calcium, vitamin D and bone tissue metabolism have been associated with the following drugs: phenobarbital, phenytoin, primidone and carbamazepine 1,2 . Alterations in the metabolism of calcium are generally very slight and subclinical, but clear cases of hypocalcemia could occur in 4% to 30% of individuals. The intensity of the clinical symptoms depends on many factors, such as: intake of vitamin D, exposure to the sun, physical activity, other diseases that interfere in vitamin D metabolism, the positive correlation of these manifestations with the type of drug, individual drug dosage, and period of exposure, as well as polytherapy 3,6 .This study, which was conducted to assess bone mineral density and vitamin D metabolism in a sample of the Brazilian epileptic population on chronic anticonvulsant therapy, was motivated by the fact that the intensity of alterations of vitamin D metabolism and bone mass was related not only to the chronic use of anticonvulsants but also to other vari...

CONTEXT: Measurements of bone density taken by dual-energy x-ray absorptiometry are the most accurate procedure for the diagnosis of osteoporosis. This procedure has the disadvantage of measuring the density of all mineral components, including osteophytes, vascular and extra vertebral calcifications. These alterations can influence bone density results and densitometry interpretation. OBJECTIVE: To correlate radiography and densitometry findings from women with osteoporosis, analyzing the influence of degenerative processes and vertebral fractures on the evaluation of bone density. DESIGN: Retrospective study. SETTING: Osteoporosis outpatients' clinic at Hospital das Clínicas, Universidade Estadual de Campinas. PARTICIPANTS: Ninety-six postmenopausal women presenting osteoporosis diagnosed by bone density. MAIN MEASUREMENTS: Bone mineral density of the lumbar spine and femoral neck were measured by the technique of dual-energy x-ray absorptiometry, using a LUNAR-DPX densitometer. Fractures, osteophytes and aortic calcifications were evaluated by simple x-rays of the thoracic and lumbar spine. RESULTS: The x-rays confirmed vertebral fractures in 41.6%, osteophytes in 33.3% and calcifications of the aorta in 30.2%. The prevalence of fractures and aortic calcifications increased with age. The mean bone mineral density was 0.783g/cm² and the mean T-score was --3.47 DP. Neither fractures nor aortic calcifications had significant influence on bone mineral density (P = 0.36 and P = 0.09, respectively), despite the fractured vertebrae having greater bone mineral density (P < 0.02). Patients with lumbar spine osteophytes showed greater bone mineral density (P = 0.04). Osteophytosis was associated with lumbar spine bone mineral density after adjustment for fractures and aortic calcifications by multiple regression (P = 0.01). CONCLUSION: Osteophytes and lumbar spine fractures can overestimate bone density interpretation. The interpretation of densitometry results should be carried out together with the interpretation of a simple lumbar spine x-ray in elderly women.