Comparison of cement pressurisation in flanged and unflanged acetabular cups.

BACKGROUND: This biomechanical study examined difference in cement pressures generated by flanged and unflanged acetabular cups in hip arthroplasty. METHOD: Using a model acetabulum, cement was inserted and pressurised followed by cup insertion and pressurisation. Pressures were recorded using transducers in the acetabulum. We compared Charnley Ogee (flanged), Exeter contemporary (flanged) and Exeter low profile (unflanged) cups using Simplex and CMW1 cements in turn. RESULTS: Using Simplex, Charnley Ogee cup generated highest initial peak pressure and overall mean pressure. Exeter unflanged cup generated higher initial and mean pressures compared to Exeter flanged cup. With CMW, there was no significant difference between the pressures generated by the cups. CONCLUSIONS: Our experiment suggests that flanged cups do not consistently generate significantly higher cement pressures compared to unflanged cups.