COMPLICATIONS OF FEMORAL AND ACETABULAR MODULARITY

The versatility of modular total hip arthroplasties have rapidly exten ded their applications. However, these new interfaces can lead to comp lications that were not observed with monolithic components. These pro blems have been noted with modular femoral and acetabular components a nd have been associated with the generation of particulate debris. Thi s article reviews the authors' clinical observations and histologic, b iomechanic, and spectophotometric evaluations of modular total hip art hroplasties. New data comparing both synovial fluid metal levels in we ll-fixed and loose monolithic and modular prosthetic hip implants are presented. In modular total hip components synovial fluid cobalt level s correlated positively with patient weight and length of implantation . The generation of particulate debris in modular total hip components may induce periprosthetic osteolysis. Taper locks for femoral compone nts and locking mechanisms for the polyethylene liner and metallic cup must be designed to avoid the production of particulate debris.