14 A NEW TYPE OF BRACHYPHALANGY IN MAN. 



III. METHOD OF EXAMINATION. 



Special features in the character under consideration soon convinced 

 us of the absolute unreliability and insufficiency of second-hand infor- 

 mation. It was found necessary to pay fully as much attention to 

 those said to be normal as to those reported to be brachyphalangous. 

 A satisfactory examination had to comprise photographs and radio- 

 graphs in both cases. In some cases it was almost impossible to per- 

 suade members of the family to permit photographs and radiographs 

 to be taken. This was especially true with regard to those who con- 

 sidered themselves to be normal; but we are indebted to other family 

 members who took special interest in the work and tried to help in 

 every way possible. 



We have thus been able to trace the abnormality without any break 

 through six generations. The photographs of the malformation cover 

 five generations, the radiographs four. In the line of the family which 

 forms the principal subject of the present publication we have secured 

 photographs of the hands of all the members of four generations 

 with only two exceptions, two children who died young. In the large 

 majority of cases we have also succeeded in obtaining radiographs of 

 the hands. This complete collection of radiographs has furnished us 

 with measurements of the hand phalanges of both the normal and 

 abnormal members of the family exact numerical material invaluable 

 for the analysis of the inheritance of the character. 



In order to get this collection of measurements as complete as pos- 

 sible we have usually been forced to abstain from taking radiographs 

 and photographs of the feet. Because of malformation due to wearing 

 shoes, the radiographs of the feet in general are not nearly as favorable 

 as those of the hands for measuring shortened phalanges. We have 

 therefore endeavored to gather only sufficient radiographs of affected 

 feet to demonstrate that the abnormality affects the same phalanx of 

 hands and feet symmetrically; that it shows symmetry and vertical 

 correspondence as well. 



The lengths of the phalanges were secured from the radiographs by 

 measuring in millimeters the distance between the center of the proxi- 

 mal and the center of the distal articular surface, this distance repre- 

 senting the axis of the bone in question. No difficulties are involved 

 in determining the latter of these two points. The distal articulation 

 surface is convex and the line marking this limit of the phalanx is 

 therefore always perfectly clear in the radiographs. 



Not quite so easy is the determination of the other measuring-point. 

 The proximal articular surfaces of the middle row of phalanges present 

 a slight middle elevation and two lateral depressions adapted to articu- 

 late with the condyles of the first phalanges. The articular surface as 

 a whole being slightly concave, a lighter shadow of the peripheral parts 



