[Functional anatomy of humero-radial articulation]

From a theoretical study combined with dissection of twelve joints and the building of a mechanical model, the authors describe the contact zones between capitulum and conoìdal zone of the humerus on one hand, and cupule and radial bevel-edge on the other, and this, during the various phases of pro-supination. In supination, the contact is essentially forward. In pronation, it is mostly backward. In each position, it is approximately the same area of the cupule which is in contact with the capitulum. The best fit is in the functional position. Major displacement occurs with almost flat cupules, displacement is minimal with hollow cupules which correspond to rounder heads.