Cement penetration into human cancellous bone dependent on broach surface design.

Aim: The purpose of this investigation was to study two different broach su rface designs with regard to cement penetration into human cancellous bone. Methods: In a cadaver study 15 paired human cadaver femora were prepared u sing broaches of identical geometry but different surface characteristics. All left femora were prepared using chipped toothed broaches, all right fem ora using diamond shaped broaches. Cancellous bone was irrigated with 1 lit er pulsed lavage. The specimens were imbedded in specially designed pots. B one cement was applied in a retrograde manner and subjected to a standard p ressure protocol with a constant force of 3000 N. Radiographs were taken an d horizontal sections were obtained at predefined levels using a diamond sa w. Microradiographs were taken and analyzed using image analysis to assess cement penetration into cancellous bone. Results: Pressure curves recorded during cement pressurisation were comparable. The microradiographic evaluat ion revealed no significant morphometric differences in the different group s with regard to cement penetration into cancellous bone. These findings we re similar in all sections obtained. Conclusions: A standardized model was developed allowing comparison of cement penetration into cancellous bone de pending on bone preparation. In the presence of pulsed lavage there is no s ignificant influence of broach surface characteristics on cement penetratio n into cancellous bone of the upper end of the femur.