An in vitro study of the effect of environment and storage time on the fracture properties of bone cement.

Changes either within the bone cement or at the cement-bone interface are known to contribute to loosening and hence failure of many cemented joint replacements. This study examines the in vitro changes in the fracture properties of bone cement as a result of storage, at both 21 and 37 degrees C, in air, water, Ringer's solution and lipid over a period of 2 years. Specimens stored in the fluid media were found to behave in a more ductile manner than those stored in air. Samples stored at 37 degrees C behaved in a more brittle manner than those stored at 21 degrees C. Although the work of fracture values measured for the samples stored in the water-based media increased during the first 18 months, this was followed by a decrease in the subsequent 6 months.