Roentgenologic Changes in Malacic Diseases of Bone

Abstract

THE past several years have witnessed the accumulation of a voluminous literature concerning malacic diseases of bone, particularly hyperpara-thyroidism. This was stimulated largely by the report of Mandl (1), in 1926, of a case of osteitis fibrosa cystica generalisata (von Recklinghausen's disease), in which the removal of a parathyroid adenoma was followed by prompt clinical improvement. Since that time, the existence of “hyper-parathyroidism” as a definite clinical entity has become well established. Because of the profound influence of the parathyroid glands on the fundamental metabolism of calcium, and probably of phosphorus, it is not surprising that the question of parathyroid function, as related to other forms of malacic disease of bones, the origin of which is supposedly known or unknown, has been seriously considered. Some enthusiastic investigators see in hyperparathyroidism a ready explanation for the cause of such conditions as osteitis deformans (Paget's disease), leontiasis ossea, ankylosing polyarthritis of Oppel, giant-cell tumor, multiple myeloma, and scleroderma. Others are less ready to accept such a broad application of the term “hyperparathyroidism.” Because of such conflicting opinions, no little confusion has resulted, particularly in the minds of roent-genologists, concerning the identity of certain forms of malacic disease of bone. Without doubt, the present intensive clinical and investigative work that is being carried out on the subject of hyperparathyroidism and mineral metabolism in general will have a far-reaching effect on our knowledge and classification of certain lesions of bone. The problem is not an easy one, for it involves not only the intricate biochemistry of mineral metabolism, but also the function of the ductless glands and the complexities of their interrelated activities. With a full realization of this situation, the classification in Table I is offered, subject to revision. It does offer, at the present time, however, a reasonable basis for a discussion of the roentgenologic changes in the various forms of malacic diseases of bone. Because of the multiplicity of conditions that may affect the mineral content and structure of the skeleton, the early recognition of any particular disease by roentgenograms alone may be exceedingly difficult. Even in some advanced lesions, as will be pointed out subsequently, the ultimate diagnosis can be made only by proper correlation of the clinical data and other laboratory findings. Atrophy Atrophy of bone, which results from disuse incident to trauma, fracture, arthritis, neurotrophic disorders, or circulatory disease, is characterized by its limitation to the affected part.