[Comparative structural analyses of the spongy bone of lumbar and cervical vertebral bodies. Radiological-morphometric and statistical studies].

To investigate the question as to a possible insufficiency of the osteoblasts with increasing age, autopsy material obtained from 105 deceased of both sexes at an age of 16 to 91 in whom clinically manifest bone diseases had been excluded, was studied. The structure of the spongy bone of the 3rd to 5th lumbar vertebral bodies (LVB) and of the 5th to 7th cervical vertebral bodies (CVB) was examined quantitatively-morphometrically, and the results were submitted to a statistical evaluation. In the three LVB, Vv, Sv and S/V behave in a similar manner. Here, Vv and Sv decrease after the age of 50 by more than 1/3, while S/V remains constant throughout live. In all the structural parameters, the three lower CVB have higher values than do the LVB. The age-dependent changes, in contrast, are only very slight. This differing behaviour of the spongy bone in the two regions of the spinal column is an expression of the characteristic loading forces in the respective regions: LVB loading is predominantly static, CVB loading mainly dynamic. Thus, from this functional point of view, physiological osteoporosis due to aging, so-called, is merely an expression of an aging bone adapting - in the same way as the bone of a young adult - to the current loading forces acting upon it.