Fatigue properties of bone cement. Comparison of mixing techniques.

A four-point bending test was made on 54 specimens of CMW, Simplex P, and Zimmer LVC bone cements. The samples were cyclically loaded at a stress level of 20 MPa at a frequency of 4 Hz. The different cements were mixed either by hand or mechanically with or without a 0.15-bar vacuum. Mechanical mixing in a vacuum improved all three cements, and was the best of all the tested mixing techniques. Simplex P showed the best fatigue properties regardless of mixing technique.