6 A NEW TYPE OF BRACHYPHALANGY IN MAN. 



phalanx of the second fingers and toes. This character is inherited 

 within a Norwegian family, some members of which have emigrated to 

 North America. Our attention was called to the material by Dr. 

 Frimann Koren, of Christiania, who observed the malformation in 

 some members of the family 15 years ago. 



Dr. Frimann Koren, who intended to study the inheritance of the 

 character, showed foresight in securing not only ordinary photo^aphs 

 but also radiographs and casts of the hands of four affected members, 

 viz, a father and three of his sons. Being prevented from carrying 

 out the investigation himself, he later very generously permitted us to 

 do it, and at the same time he kindly transferred to us the material 

 he had already collected. We wish to express to him our most sincere 

 thanks for this courtesy. 



Through the interested and intelligent cooperation of two members 

 of the family we have since been able to gather detailed information 

 about the pedigree for six generations, an investigation that has been 

 greatly faciUtated by the fact that the family owns an old "family 

 book" with elaborate data concerning each member of the earliest 

 three generations dealt with ia this paper. The photographs of the 

 malformation cover five generations, the radiographs four. 



The material here studied may be regarded as especially favorable 

 because the brachyphalangy is always restricted to a single and the 

 same phalanx, and a numerical expression for the character can be 

 obtained by measuring from the radiographs the long axis of the 

 affected phalanx. These data have made possible the analysis of two 

 distinctly different somatic types under which the brachyphalangy 

 manifests itself. A suggestion is given for an explanation of these types 

 on a genetic basis. Much attention is paid in the investigation to this 

 special point. 



The family studied includes a case of intermarriage, giving rise to an 

 individual that is interpreted as homozygous for brachyphalangy. 

 This case reveals features of special interest from a medical point of 

 view. 



As to the name used in this paper to characterize the abnormality, 

 the following might be mentioned: Farabee, when he described the 

 anomaly often spoken of later as "Farabee's disease," used the name 

 hypophalangia, or diminution in the number of phalanges (1905). 

 Drinkwater, in his papers dealing with the same subject, uses the term 

 of the old anatomists brachydactyly, which is still generally adopted in 

 pathological anatomy and clinics. According to Drinkwater, the fin- 

 gers are in "brachydactyly reduced to about half the normal length" 

 (1915). As a special type he separates "minor brachydactyly." 

 The fingers are here "intermediate in length between these very short 

 ones and the fingers of average normal individuals" (1915). 



