Controlled plastic deformation for the fastening mechanism of an internal fixation device. The new Mennen 3 PeriPro
C A Pappas1, P G Young, A J C Lee
1Department of Engineering, School of Engineering, Computer Science and Mathematics, University of Exeter, Exeter, UK. c.pappas@exeter.ac.uk
Abstract:
The Mennen femur plate is a fixation device used for the treatment of femoral periprosthetic fractures. It features a novel fastening method where curved prongs are plastically deformed securing the implant to the bone. Although this "clamp-on" method has been successfully used to treat fractures of long bones, there are no literature data assessing the nature of the required plastic deformation. In the present study, the parameters influencing the performance of the prongs were identified and further explored using numerical modeling. The new Mennen 3 PeriPro plate is briefly discussed focusing on the new sculpted formation of the prongs. Their design was optimized to effectively control the magnitude and position of the required plastic deformation achieving enhanced anchorage on the fractured bone with minimum effort. The work presented contains all the necessary steps in analysing a clinical problem using finite elements and illustrates how effective use of simulation techniques can accurately predict and effectively control the required plastic deformation of a structure.


