Development of the Mennen 3 PeriPro fixation plate for the treatment of periprosthetic fractures of the femur

Abstract

The Mennen femur plate is an internal fixation device used for the management of femoral perisprosthetic fractures, usually after total hip replacement surgery. The implant uses a number of curved prongs that embrace the fractured bone around its circumference without interfering with the stem of the prosthesis. Although the device has been used with considerable clinical success since its first introduction, a number of negative clinical results have been reported in the literature. The failure modes of the device are described and an evaluation of its performance is briefly presented. Based on this assessment as well as comments in the open literature, modifications in the design of the device have been implemented. The new Mennen 3 PeriPro plate is presented, with all the necessary data for a coherent explanation of its improved characteristics as defined using numerical simulations and experimental tests. The new device has all the beneficial features of the previous plate with improved structural performance and fatigue life and new sculpted formation of the prongs, providing a simple implantation technique with maximum gripping and minimum effort from the surgeon. The unique mode of fixation has been further improved, providing ample anchorage on the fracture bone without compromising its biomechanical integrity. By combining the device with a cable system, the spectrum of applications will be further expanded, enabling the surgeon to treat a broader range of fracture patterns.