NO. 6 



EAR EXOSTOSES HRDLICKA 



25 



Hyperostoses and Exostoses Cases" Observed by Korner '0(?i/ 



Age 



o- 5 

 6-10 

 11-15 

 16-20 

 21-25 

 26-30 



31-35 

 36-40 



41-45 

 46-50 



51-55 

 56-60 

 61-65 

 66-70 

 Over 70 



Subjects 



113 

 116 



"5 



78 



77 

 74 

 74 

 68 

 61 

 38 

 45 

 29 



19 

 12 



Subjects with exostoses 



and hyperostoses 



and percent in total 



number of growths 



Number 



= 

 2 = 



6 = 



11 = 

 13 = 

 17 = 



12 = 

 16 = 



13 = 



7 = 



8 = 

 10 = 



4 = 



5 = 



1 = 



Percent 

 O 



1.6 

 4.8 



10.4 



13.6 



9.6 



12.8 



10.4 

 5-6 

 6.4 

 8.0 

 32 

 4.0 

 0.8 



125 = 100. o 



To the above I am able to add data which I have culled from addi- 

 tional clinical reports, showing loi cases where some information as 

 to age was given. Of these, in 25 cases the subjects were merely 

 marked as " adult ", or " of mature age ", or " elderly ". The yj sub- 

 jects whose age was stated range as follows : 



The greatest frequencies of the bony growths in the external audi- 

 tory canal are registered, it is seen, between the ages of 20 and 50. 

 Their period of prevalence extends chiefly from 16 to 60. They are 

 rare below 10 and but one had so far been recorded above 70, though 

 the distribution in our table indicates that a few cases do probably 

 occur above that age. 



The condition or " disease ", if it can be called such, is therefore, 

 it is clear, dominantly one of the earlier to middle adult life, and has 



