[The two columns of the lower end of the humerus]

The anatomical examination of the distal end of the human humerus brings new perspectives. The lower extremity of the humerus is considered as a structure with two diverging columns that prolong the diaphysis and flank the trochlear mass articulate with the ulna. Two series of dry humeruses, one of 100, and the other 20 permitted a study with measurements of the posterior width of the columns, their antero-posterior dimensions, the angle that they form with the posterior longitudinal axis of the diaphysis. Dry bones, radiographs, and direct tracing were used. The second series of bones was used for cross-sections in several planes, and for perforations of the fossae. Lastly, graded cuts of frozen elbows were done. These methods showed the two columns to be completely different. The outer column is thick, quadrangular, bulky, convex at the back, wide, almost vertical; in front it bears the condyle, while a lateral facet appears on its distal part; this column is articulated with the radius and extends itself to the thumb column. The inner column is fusiform, narrow, oval on cross-sections; it is a column which supports the trochlea and the muscles, two roles played also by the outer column.