Mineralização óssea em adolescentes do sexo masculino: anos críticos para a aquisição da massa óssea

Abstract

Objective: To verify the behavior of the mineral bone content and density in male adolescents according to age and secondary sexual characters.Methods: 47 healthy adolescents between 10 and 19 years old were assessed according to weight, height, body mass index, puberty stage, calcium intake, bone mineral density and content in the lumbar spine and in the proximal femur. The bone mass was measured through bone densitometries. The intake of calcium was calculated through a 3-day diet. The BMI (body mass index) was calculated with the Quetelet Index and the puberty stage was defined according to Tanners criteria. The analysis used descriptive statistics such as average and standard deviation, and variance estimates to compare the different age groups. Moreover, the Tukey test was used to determine the significant differences.Results: It was evident that the calcium intake in the different ages assessed has not reached the minimum value of 800 mg. The bone mineral density and content showed an increase after the age of 14, as well as when the teenagers reached the sexual maturation stage G4. The mineralization parameters showed a high level when the teenagers were in the G3 stage, however, without statistical significance. Conclusion:The results indicate an important level of bone mineralization during adolescence. Maturation levels superior to G3 have shown more mineralization. This study proves that the critical years for bone mass gain start after the 14-15 years old or older.J Pediatr (Rio J). 2004;80(6):461-7: Adolescence, puberty stage, secondary sex characters, bone mass, bone mineral density.

Lesões esportivas: um estudo com atletas do basquetebol bauruense

“…DISCUSSãO Indivíduos cuja faixa etária está entre 13 e 17 anos são caracterizados pela rá-pida aquisição de conteúdo mineral ósseo. Nessa fase, ocorre o pico de massa óssea, que é quando o processo de formação sobrepuja o de reabsorção óssea (PhilliP;lazar, 2003;silva et al, 2004;Pettersson et al, 2000). Astrand (1992) complementa que indivíduos dessa faixa etária, tanto no aspecto funcional quanto no aspecto estrutural, não são semelhantes aos adultos.…”

Conteúdo e densidade mineral óssea de adolescentes do sexo feminino. DOI: 10.5007/1980-0037.2011v13n5p354

“…Only two studies evaluating these aspects were found until now. One study only included adolescent boys 11 , whereas the other evaluated adolescents of both genders ranging in age from 6 to 14 years 12 . Therefore, the objective of the present study was to characterize bone mineral content (BMC) and BMD in adolescent girls according to age and pubertal stage.…”

Densidade mineral óssea de adolescentes com sobrepeso e obesidade

“…7 In a recent study with Brazilian adolescents, the authors have described a remarkable increase in bone mineralization as a result of sexual maturation, pubertal stage above grade IV and age older than 14-15 years. 8 Approximately 85-90% of the final bone mass in adults is achieved up to the age of 18 years in girls and up to the age of 20 in boys. From then on, it remains constant up to the fourth decade of life, when there is gradual physiological loss due to the advancement of age.…”