4 CLINICAL APPLIED ANATOMY. 



open to receive blows are apt to become the seat of inflammation, 

 a good example being the shin. 



Sometimes the damage done to the tissues by subcutaneous 

 injuries prevents their being able to resist the onslaught of 

 bacteria reaching them in the blood. Hence it is that 

 inflammation, and possibly subsequent suppuration, may occur 

 in the part injured. 



Again, portions of skin liable to friction, as, for instance, where 

 the back of the neck is rubbed by the collar, are frequently the 

 site of inflammation, due to bacteria being rubbed from the 

 surface into the hair follicles and glands. Furuncles or boils 

 are thus induced. A " sore heel " from the friction of the boot 

 in walking is another common example of the same kind. 



Intermittent pressure, such as happens over the metatarso- 

 phalangeal joint of the great toe, will lead first of all to the 

 formation of an adventitious bursa, or bunion, and often subse- 

 quently to inflammation of the same. 



Parts subject to strains, particularly joints, are peculiarly 

 liable to become inflamed. Of all the joints of the body the 

 knee-joint would seem to be the most susceptible. 



The more exposed mucous membranes are those which most 

 frequently suffer from attacks of inflammation. Thus it is that 

 catarrh of the nasal mucous membrane is met with every day, 

 and that tonsillitis is so prevalent. The mucous membrane 

 of the alimentary tract is readily irritated, and consequently 

 inflamed, by material brought to it through ingestion of improper 

 food, and peculiarly so by bacteria. 



SUPPUKATION. 



When pus is formed in the tissues it has a tendency to find 

 its way along the lines of least resistance to the skin surface, 

 or into one of the cavities of the body. Therefore it is that 

 the structures within which suppuration occurs have a marked 

 bearing from their anatomical peculiarities and relations upon 

 the actual course taken by the pus in its passage to an exit. 



