758 FRANCIS H. McCRIJDDEN 



mortem examination of the bones, especially the pelvic bones, of twenty 

 pregnant women who, during life, were apparently free from any symp- 

 toms of the disease. 



Clinical evidence, too, points in the same direction. Fehling(&) 

 has observed that many women who have several quickly succeeding preg- 

 nancies have the subjective symptoms of osteomalacia pain and tender- 

 ness in the pelvic bones without the deformity observed in undoubted 

 osteomalacia, and has suggested that. these are mild cases of the disease. 



Careful examination by McCrudden(e) of the clinical histories of 

 as many cases of osteomalacia as could be found in the literature brought 

 out certain clinical facts in harmony with the chemical and histological 

 findings which are not emphasized in the text books: In the first place, 

 osteomalacia rarely begins in the first, or even in the second pregnancy, 

 but usually after several rapidly succeeding pregnancies, and, further- 

 more, is usually seen only in poor women whose hygienic environment 

 is bad. As a rule, the first attack appears during the later months of 

 pregnancy and the patient recovers after parturition. A second attack 

 may not occur. But if pregnancies succeed each other rapidly, other 

 attacks occur, and the succeeding attacks begin earlier and earlier, in 

 succeeding pregnancies, are more severe, and last longer after the preg- 

 nancy is ended, until finally there is no longer any recovery. In other 

 words, it is only after a long continued and severe drain on the bones 

 of a poorly nourished patient that the body fails to respond to the demands 

 on it, and even then recovery follows if the severe demands are not con- 

 tinued. Of course, not every case runs like this, but this is the typical 

 course of the disease. 



These clinical features seemed so important and suggestive that a 

 search was made to see if other investigators had not made similar observa- 

 tions. As early as 1829 (Kilian), it was observed that osteomalacia 

 occurs chiefly in women who have been pregnant many times in rapid suc- 

 cession; and in 1857 Kilian pointed out that puerperal osteomalacia 

 tends to recovery, only to undergo exacerbation during a succeeding preg- 

 nancy. Numerous other writers have since called attention to these 

 facts, Senator (c), Cohnheim(6),, Latzko, Sternberg(a), Everke, Zesas. 



The observation made by Cohnheim(&) and by Zesas that frac- 

 tures during pregnancy are slowly repaired (a proper callus is formed 

 with difficulty), is a point in favor of the theory that a flux of calcium 

 from the bones to the growing fetus is responsible for puerperal osteo- 

 malacia. Sufficient lime salts needed for callus formation are not available. 



Chemical, histological, and clinical evidence, then, are in accord, and 

 in harmony with the view that osteomalacia is but an exaggeration of 

 the increased metabolism of the bony tissues in pregnancy. Normally, 

 the anabolic and catabolic processes in the bones balance each other. 

 In pregnancy, as a result of increased needs of the fetus for lime salts, 



