The rotational alignments of the distal femur in southern Chinese subjects were investigated. Chinese femurs are significantly more externally rotated. This is new evidence to suggest a racial difference in the distal femoral geometry. During total knee arthroplasty, a common recommendation is to allow 4 degrees of external rotation. The clinical significance of our study is that this need to be modified to 6 degrees for Chinese women and 5 degrees for Chinese men. This racial difference can be incorporated into a new concept of "a mountain and a molehill." This concept is presented in this report.