NO. 6 EAR EXOSTOSES HRDLICKA 65 



The Indian and other material that passed throui^h my hands sus- 

 tains the view that the fundamental causes of ear exostoses are quite 

 different from mere irritation or inflammation. Most of the specimens 

 with such growths in our collections show no detectable inflammatory 

 changes. Nor are the growths themselves, in a large majority of cases, 

 such as would suggest inflammation. They and the parts about them 

 show nothing like the periostitic bone deposits or osteitic indurations 

 that are so well marked elsewhere in the skull or skeleton where 

 inflammatory processes affected the bone. Our material suggests 

 strongly that, in general, otorrhoea and other otic derangements may 

 not precede but rather follow ear hyperostoses and exostoses, after 

 these have begun to reach an obstructive stage. 



SALT WATER 



Connected with the preceding category of causes, yet having some 

 individuality of its own, is the irritation of the ear by water and 

 more particularly salt water. A number of authors incline to regard 

 this as a cause of ear exostoses in some instances. 



Thus in Field's (1878) cases, two of his four patients attributed 

 their ear troubles, which proved to be exostoses, to repeated and pro- 

 longed sea bathing. For Korner ( 1894) exposure to sea water " was 

 influential " — he found them more than five times as common along 

 the seacoast of Germany as in the interior. Moore (1900, p. 786) re- 

 ported that ear exostoses were " very common in the Hawaiian Islands, 

 where great fondness for aquatic sports is supposed to be a cause." 

 Tod (1909) blamed "gout and the morning tub." For Law (1909, 

 p. ']']) " a causative factor seemed to be the pouring of water into the 

 ears, especially carelessly sponging while holding the head on one 

 side " ; and for Jackson ( 1909) it was " local irritation, principally by 

 sea water." Jackson thought irritation by salt water to be a more 

 frequent cause of ear exostoses than any other. McKenzie ( 1920, 

 p. 458) says, " they are very common in people who indulge freely in 

 sea-bathing and diving." 



For Heiman ( 1890) the case is " hard to decide." In a case of Lake 

 (1898) the subject "had never had a sea bath." And for Moller- 

 Holst (1932, p. 102) the claim, with some others, is " so unfounded 

 that no discussion of it is necessary." 



Remarks. — Some efforts were made to connect the frequency of 

 ear exostoses in the Peruvians and the Channel Islands Californians 

 with sea bathing. It was not known then that the abnormalities would 

 be found to be even much more frequent in some of the inland tribes ; 

 that they also occurred in parts of Peru where no one bathed ; that they 



