296 ALBERT EHRENFRIED 



(1) Its distribution corresponds to a primitive anlage, implying an in- 



nate anomaly of the germ plasm; 



(2) The identical affection can be traced back through previous genera- 



tions, and 



(3) All other causes can be ruled out. 



Disorders originating before birth (no matter when they first become 

 apparent) may be divided into two major subdivisions, those that are innate 

 or inherent and those acquired in utero. The first class can be divided into 

 those that have been shown to be hereditary, such as hemophilia, and those 

 which have not been shown to be hereditary, such as hare-lip. The second 

 class can be divided into mechanical, such as intra-uterine fractures or am- 

 putations, and infective, for instance congenital syphilis. 



Such a scheme as this suggested is inclusive enough to cover the entire 

 field, simple enough to allow of easy comprehension and retention, and is 

 clear cut in its definition. Further subdivisions will readily suggest them- 

 selves. 



The affection which I am discussing particularly has been known for cen- 

 turies as something of a freak of nature, but only within comparatively 

 recent years has it been the object of serious scientific study. In 1915 (1) I 

 reported a single case with pathological study at the annual meeting of the 

 American Medical Association as something of a rarity, but within two years 

 I was able to collect in Boston twelve more personal cases. We now know 

 that the affection occurs all over the globe, and its hereditary nature has 

 been established. Percy Stocks reporting in 1925 (2) from the Francis Gal- 

 ton Laboratory for National Eugenics of the University of London, was 

 able to collect 1237 well-defined cases reported in the medical literature. 

 The distribution, as in other known hereditary diseases, is sex-linked, — males 

 being affected predominantly, in the proportion of 3 to 1. 



The pathology depends essentially upon a retardation and disorderly 

 exhuberance in the bone-forming function of the epiphyses of the long bones. 

 But any bone laid down in cartilage — (ribs, pelvis, vertebra) — may be in- 

 volved. In the majority of cases (about 70 per cent) this growth distortion 

 involves the skeleton symmetrically; in some, one side of the body is more 

 affected than the other, and in an unusual case one side alone is affected. 



As a result of the lack of orderliness the bones become thick or irregular 

 toward their ends, and bony overgrowth occurs. The process ceases, 

 naturally, with the cessation of skeletal growth. 



As a result of the retardation, the arms and legs are abnormally short in 

 relation to the body; the patient is accordingly short in stature and the hands 

 hang high. Sometimes the dwarfing is extreme. 



