THE SI^LETON AND ITS JOINTS 359 
Osteitis Deformans. 
Dr. Corson-White was fortunate enough, during the 
course of her work upon osteomalacia of monkeys, to 
detect a specimen which, did not show the usual excessive 
excretion of calcium but on the other hand retained this 
element and evinced alkali hunger. The general appear- 
ance of the specimen was similar to that of monkeys 
having osteomalacia but at autopsy a definite picture of 
Paget 's disease or osteitis deformans was discovered. 
This led to a search for cases in the literature and to the 
following study, which I paraphrase and condense from 
Doctor Corson-White's notes. 
Osteitis deformans is a chronic constitutional affection 
characterized by the absorption of compact bone, chiefly 
in the cranium and long bones, and the laying down of 
fibro-osteoid tissue in such an excess as to enlarge the 
affected bones. This material, which is soft and cuts 
with reasonable ease, has calcareous matter in it as shown 
by Rontgen-ray examination. Paget described it in a 
classical article in 1876(3) since which time the reported 
cases have mounted to three hundred and fifty. Because 
it has only been recognized in its best developed stages, 
it may be that early mild or arrested cases have been 
overlooked. Judging by the instances claimed to have 
been found in museum collections of bones, it is probably 
an affection dating to antiquity. So far these remarks 
apply only to man but in lower animals the reports are 
very few and those are not available in the original. The 
abstracts and references show considerable confusion. 
The names osteitis deformans, osteoporosis, osteitis 
fibrocystica, osteodystrophia deformans and osteosar- 
coma, leontiasis ossei, etc., are used almost interchange- 
ably. In 1901 Barthelemy (4) described a condition 
(Maladie du Son) in horses in which there was a marked 
enlargement of the head and of the epiphyses of the long 
(3) Med. Chir. Trans., Vol. 60, 37, 1877. 
(4) These de Lyon, 1901. 
