Removal of bone cement from the femoral canal using an acoustic emission-controlled milling device.

The removal of bone cement from the femoral canal in the case of hip prosthesis loosening takes a considerable amount of time and carries the additional risk of complications, thus risking bone damage and perhaps even endangering the successful reimplantation of a new prosthesis. We have demonstrated experimentally that the milling of bone and bone cement produces acoustic emission waves of different intensity. These waves can be measured by a commercial acoustic emission transducer. This method enables us to control a milling device during the removal of bone cement from deep in the femoral canal, avoiding the serious damage to the bone and thus enabling a new prosthesis to be reimplanted.