OSTEOMETRY; THE MEASUREMENT OP THE BONES 145 



Humerus; Greatest length (1), as taken with the osteometric board 

 OB. 



Radius; Physiological length (2); from the center of the capitellar 

 depression proximally to the center of the slight ridge which crosses the 

 distal articulation transversely. Cr or SC 



Femur; Physiological length (2) ; as taken with the osteometric board, 

 and with the two condyles in contact with the transverse plane. OB. 



Tibia; Physiological length (3); from the deepest point in the arti- 

 cular surface of the medial condyle to the deepest point in the distal 

 articular surface just within the medial malleolus. Cr or SC. 



The following indices are in common use :- 



, . , T . , radius length X 100 



1 Radio-humeral index ? -, rr 



humerus length 



This is an old index, formerly much used notably by Broca in 1862, 

 and by Turner in 1886. In both cases the greatest lengths were used, 

 and the arms (radii) were classified as follows : 



Index below 75 brachycercic 



75 to 79 mesaticercic (mesocercic) 



Index above 79 dolichocercic 



Europeans, Lapps, Eskimo, and Bushmen are brachycercic; Australians, 

 Negroes, Hindu, Chinese, and American Indians, except Fuegians, are 

 mesocercic; Andamanese, Negritoes, and Fuegians, are doliehocercic. 



o m-i- f t j tibial length X 100 



2 Tibio-femoral index ^ 



femoral length 



This index corresponds exactly to the previous one, being for the leg 

 what that is for the arm, i.e., a proportionate measure for the distal 

 joint. 



These indices are classified into two groups by the boundary number 83, 

 all indices below this being brachycnemic; all above it dolichocnemic. 

 To the first belong the Europeans, Chinese, Tatars, Lapps, and Eskimo; 

 to the latter the Australians, Negroes, Andamanese, and American 

 Indians. 



, T . , length of humerus + radius X 100 



3 Intermembral index - -r T~i ~Tn^ 



length of femur + tibia 



For this, both Turner (1886) and Martin (1893) used the maximum 

 lengths of all the bones concerned, as ascertained by the osteometric 

 board, but the differences between these results and those obtained by 

 the more exact physiological lengths are but slight, and the data thus 

 obtained may be considered as practically correct. For comparisons 

 involving both bones and the living, however, the physiological lengths 

 should be used, as the two may then be closely compared, or even used 

 interchangeably. The most important results of the two investigators 

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