Fractures of the femoral stem component in total hip Arthroplasty have been a well documented complication. The incidence over recent years has decreased due to improvements in both surgical technique and implant design and manufacture.

We report two cases of femoral stem fracture. Both occurred in CDH stems from the C-stem system (Depuy International, Leeds, UK). Both patients were women weighing 83kgs and 89kgs at the time of fracture. The fractures occurred at 46 and 24 months respectively.

The design of the CDH stem is fundamentally different from the rest of the primary stems with absence of the medial strut. In addition to this factor, both stems fractured through the insertion hole, which acted as a stress raiser. Also of note was the fact that both patients BMI’s were above 25. No weight restrictions have been imposed by the company on this implant.

We conclude that if at all possible, a primary C-stem should be inserted but if a CDH stem is used attention to patients’ weight is paramount.