@entity79 ( @entity79 ) of the @entity8546 was assessed by dual energy X-ray absorptiometry (DXA) in four different regions of the @entity8546 in 20 pre-menopausal and 55 post-menopausal @entity1 , none of whom were on treatment or suffering from conditions affecting bone. The total body option in the small animal software package of a Lunar DPX-L bone densitometer was used. The precision of the technique (%CV) varied from 0.7 to 2.2% depending on the region scanned. For post-menopausal @entity1 , @entity79 results in the mid and posterior parts of the @entity8546 varied by < 7% while @entity79 in the anterior region was about 20% lower. DXA of the @entity8546 was compared with measurements at the spine (L2-L4) and hip (femoral neck) and changes with age were estimated from cross-sectional data. @entity79 of the @entity8546 was significantly reduced in 28 post-menopausal @entity1 with low lumbar spine @entity79 (-2SD) compared with @entity1 with normal spine @entity79 . Calcaneal @entity79 was significantly correlated to axial @entity79 (r = 0.45-0.77) and to age (r = 0.45 to -0.63). For a subgroup of 33 post-menopausal @entity1 measured twice after approximately 1 year, @entity8546 @entity79 decreased by between 1.2% and 2.5% while axial @entity79 showed no significant change. Unlike spine or femoral neck @entity79 , the decrease in @entity8546 @entity79 was significantly greater in @entity1 with low spine @entity79 than in normal @entity1 , possibly indicating improved detection of skeletal changes. The optimum measurement sites for @entity79 in the @entity8546 were within the mid or posterior part of the @entity8546 or enclosing the whole posterior @entity8546 . The @entity8546 was shown to be a precise, sensitive and simple measurement site suitable for the assessment of @entity170 , especially in the elderly where degenerative changes in the spine and hip can complicate @entity79 assessment.

The effect of region of interest selection on dual energy X-ray absorptiometry measurements of the @entity8546 in 55 post-menopausal XXXX .

@entity1 :: ('9606', 'Species') :: ['women'] @entity79 :: ('MESH:D001847', 'Disease') :: ['Bone mineral density', 'BMD'] @entity8546 :: ('MESH:C566069', 'Disease') :: ['calcaneus'] @entity170 :: ('MESH:D010024', 'Disease') :: ['osteoporosis']
@entity1 :: (9606,Species) :: ['women']
