Instrumental diagnosis of osteoporosis

Bone mineral density in university aged Saudi females

Objective:

The aim of the study was to investigate bone mineral density (BMD) in young Saudi females (20-25 years) using Dual-energy x-ray absorptiometry (DXA), as it is a widely utilized modality for the measurement of BMD, used for the diagnosis of osteoporosis and osteopenia.

Methods:

BMD measurements were performed in the spine and the neck of the femur in 101 young females.

Results:

37% and 34% patients had osteopenia in the spine and the neck of the femur respectively, BMD values = 0.98 and 0.81 gm/cm² respectively). Whereas 5% had osteoporosis in the spine area, BMD values = 0.82 gm/cm²). Of the 101 subjects, 53 (52.5%) young females did not suffer from osteopenia in either both site, whereas 23 (22.7%) females had osteopenia in both sites, the remaining 25 subjects (25% of the subject included) had either osteopenia or osteoporosis in one of the sites. A strong association between BMD values with weight was found.

Conclusions:

We found that one third of the young Saudi females sampled suffer from osteopenia. Additionally, body weight has a positive relationship with bone mineral density.

Determination of cortical bone porosity and pore size distribution using a low field pulsed NMR approach

The objective of this study was first to prove the concept of a low field pulsed nuclear magnetic resonance (NMR) process for assessing the cortical porosity and pore size distribution of human bone in vitro, and then to apply the technique to detect age-related changes of bone in these parameters. The Carr-Purcell-Meiboom-Gill NMR spin echo train method is used to determine the porosity, and an inversion NMR spin-spin relaxation (T(2)) spectrum is used to assess the pore size distribution in cortical bone. Using these techniques, cortical porosity and pore size distribution of 19 specimens of human cadaveric bone, ranging from 16 to 89 years of age, were assessed. The NMR results were compared with the histomorphometric data of the same bone samples to verify the efficacy of the NMR approach. Moreover, a coefficient (surface relaxivity) relating the pore size to the T(2) relaxation time was determined empirically for the Haversian canals and the osteocytic lacunae. The results of this study demonstrate that the in vitro NMR approach using T(2) relaxation techniques can directly assess the porosity and pore size distribution (Haversian canals and osteocytic lacunae) in human cortical bone. In addition, this study indicates that the age-related changes in cortical porosity relate predominantly to Haversian canals, whereas the porosity of osteocytic lacunae appears to be independent of age.