An evaluation of total hip replacement cementing technique using sonic resonance.

Abstract

The feasibility of assessing the quality of the bond achieved by cement fixation of implants by their sonic characteristics was examined by theoretical and experimental models. Mechanical excitation of implants in the audio sonic range in vitro produced experimental results that were in close agreement with computer predicted values. The sonic technique was utilized to evaluate certain aspects of current surgical technique using in vitro models. By sonic criteria, steady state polymerization of surgical simplex cement occurs approximately eleven minutes after hand held cement has cured. The value of meticulous preparation of bone surfaces prior to cement introduction is confirmed. Differences in the quality of bond obtained by variations in cement technique, or recementing to old cement, can be distinguished by this method. These results suggest that sonic assessment may provide a more sensitive measure of the quality of bond achieved than does roentgen examination. In clinical use, both intra-operatively and post-operatively, application of this technique may yield an immediate assessment of the quality of cement fixation.