[Duckbill fractures of the tuber calcanei, etiology and treatment]

This report is of two cases of tuber calcanei fractures (fractures of group I according to Böhler). In one case the fracture occured after direct trauma, in the other after an uncorrdinated maximal contraction of the triceps muscle. The different origins of this type of fracture are discussed and the reported cases in the literature are reviewed. Both fractures were treated by osteosynthesis. Immediate operation is indicated because problems in the surrounding soft tissues are to be expected.