Roentgenographic Observations in Age Atrophy and Osteoporosis of the Spine

With advancing age, the bones of the human body show a well known change of structure, so-called age atrophy. This condition, described as early as 1863 by Charcot and in 1873 by Vulpian, is due to decreased functional stress, thinning of calcareous elements, and to lack of bone apposition. While simple age atrophy has no complications and does not produce any clinical symptoms, it is associated, in a certain number of cases, with decalcification of bones, producing deformities, collapse, and fractures. This condition is called osteoporosis. The differential diagnosis between normal, uncomplicated age atrophy and beginning osteoporosis may be impossible; indeed, the two conditions may occur together. When osteoporosis predominates, it usually gives rise to symptoms, and it is at this stage that the physician is consulted. One of the most frequent sites of osteoporosis is the spine, though the disease may be observed in the long bones, maxilla, and skull. The present paper is limited to the radiologic aspects of osteoporosis of the spine. Before Albright, Smith, and Richardson (1) published their observations on the importance of the menopause as an etiologic factor of osteoporosis, many other causes were assigned to the disease, including disorders of the thyroid and parathyroids, pituitary adenoma and Cushing's syndrome, suprarenal cortical tumor, disuse and inactivity. The most important radiologic findings in osteoporosis of the spine are: (1) more or less generalized bone atrophy and decalcification; (2) a ground-glass appearance of the vertebral bodies; (3) the fishbone type of vertebra due to expansion of the intervertebral disk into the brittle and fragile vertebral body; (4) crushing, compression, or fracture of the vertebral bodies with secondary deformities; (5) the kyphosis of the aged. Little has been published on the simultaneous occurrence of decalcification of the bones and marked calcifications in other parts of the body. Albright and his co-workers state that, in view of the increased excretion of calcium in the urine in the early stages of osteoporosis, it is not surprising that some of these patients have urinary calculi. According to Steindler (8), calcification of the intervertebral disk is due to disintegration, loss of elasticity, and incrustation of calcium under the influence of body weight. We wish to stress the occurrence of calcifications in neighboring or distant organs observed in 8 of the 10 cases on which this report is based. These calcifications may be overlooked if the examination is restricted to the spine, but they are easily discovered if other organs are examined. The pathological changes of osteoporosis of the spine can be observed first in the lateral view. Deformities of the vertebral bodies or the intervertebral disks which appear in the anteroposterior view are a sign that the disease is already far advanced.