Total hip arthroplasty modular neck failure.

The use of modular components in total hip arthroplasty has increased in popularity. The advantages of modularity in hip arthroplasty include improved visualization during acetabular revision and restoration of proper hip biomechanics. Disadvantages include disassociation of components, failure at modular junctions, corrosion, and the generation of metal ions and debris. We present 2 cases that demonstrate the potential for modular neck fracture, requiring subsequent revision of well-fixed components.