Biomechanical properties of ciprofloxacin loaded bone cement.

The purpose of this study was to investigate the biomechanical properties of bone cement used in joint replacement surgery after the addition of ciprofloxacin. The first group received bone cement only and served as a control for the 4 groups where 500 mg, 1000 mg, 1500 mg and 2000 mg of ciprofloxacin were added to yield 40 g of bone cement. Axial compression tests were conducted using a 50,000 Newton capacity tension-compression testing device. While axial compression strength at failure was 80.2±4.3 MPa in the control group, values in the ciprofloxacin-treated groups decreased with rising concentration of ciprofloxacin to 74.5±5.4 MPa, 70.6±4.8 MPa, 70.5±4.7 MPa, and 69.3±3.4 MPa. Bone cement with addition of 500 to 1500 mg ciprofloxacin maintained mechanical axial strength values above 70.0 MPa recommended by American Society for Testing and Materials and can be safely used in joint replacement surgery.