CHAPTER XI 
DISEASES OF THE BONES 
A. PERIOSTITIS AND OSTITIS. 
We head this section, Periostitis and Ostitis, for the reason 
that in actual practice it is rare for one of these affections 
to occur without the other. The periosteum and the bone 
are so intimately connected that it is difficult to conceive of 
disease of the one failing to communicate itself in some 
degree to the other. Pathologically, however, and for 
purposes of description, it is more convenient to describe - 
separately the abnormal changes occurring in these two 
tissues. 
With the main phenomena of inflammation occurring 
elsewhere we presume our readers are aware. Briefly we 
may put it, that under the action of an irritant, either 
actual injury, chemical action, or septic infection, the healthy 
tissues around react in order to effect repair of the parts 
destroyed. Also that this reaction involves the distribution of 
a greater blood-supply to the part, with an abundant migra- 
tion of leucocytes, and the outpouring of an inflammatory 
exudate, together with symptoms of heat, pain, redness, and 
swelling of the affected area. And that in chronic inflamma- 
tions, owing to persistence of the cause, the process of repair 
thus instituted does not stop at mere restoration of lost 
tissue, but continues to the extent of forming an abnormal 
quantity of such tissue as normally exists in the parts 
implicated. 
The process of inflammation in bone is essentially the 
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