High Initial Stability in Porous Titanium Acetabular Cups: A Biomechanical Study

Joint Replacement Surgeons of Indiana Foundation, Inc., Mooresville, Indiana.
The Journal of arthroplasty (Impact Factor: 2.37). 11/2012; 28(3). DOI: 10.1016/j.arth.2012.07.035
Source: PubMed

ABSTRACT Initial stability with limited micromotion in uncemented total hip arthroplasty acetabular components is essential for bony attachment and long-term biomechanical fixation. This study compared porous titanium fixation surfaces to clinically established, plasma-sprayed designs in terms of interface stability and required seating force. Porous plasma-sprayed modular and metal-on-metal (MOM) cups were compared to a modular, porous titanium designs. Cups were implanted into polyurethane blocks with1-mm interference fit and subsequently edge loaded to failure. Porous titanium cups exhibited 23% to 65% improvement in initial stability when compared to plasma-sprayed cup designs (P=.01): a clinically significant increase, based on experience and prior literature. The results of this study indicate increased interface stability in porous titanium-coated cups without significantly increasing the necessary force and energy required for full seating.

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