[Fracture of the ceramic head in total hip prosthesis. Apropos of 2 cases].

Fracture of the ceramic head of a replacement arthroplasty of the hip has been encountered in 2 patients. After studying the literature the causation of such fractures has been assessed. Defects in manufacture of the prosthesis, damage during its handling and incorrect use may be responsible, with the tapered neck being the principal instrument of failure. The use of a new head with a used tapered neck is not recommended. Care must be taken in placing the head on the neck and a precise fit is required with no interposition of soft tissue.