Clinical and Experimental Biomechanical Studies Regarding Innovative Implants in Traumatology

Abstract

Fracture treatment has experienced a fascinating evolution in the last years. The aim of this chapter is to reveal some clinical and biomechanical studies regarding innovative implants. After a short introduction (1), we intend to present our results regarding (2) dynamic condylar screw versus condylar blade plate in complex supracondylar femoral fractures; (3) biomechanical analysis of four types of implants in humeral fractures; (4) clinical and experimental studies for optimal stabilization of trochanteric fractures: the gliding nail; (5) intramedullary XS nail for pilon and ankle fractures: design, biomechanics, and clinical results; (6) the XS nail for the treatment of patella and olecranon fractures; and (7) plates with polyaxial stability for fractures of distal radius and proximal humerus. In conclusion, the authors highlight the advantages of these innovative implants in difficult trauma cases. Biomechanics 2 DCS versus CBP in complex supracondylar femoral fractures: a biomechanical studyDistal femoral fractures represent a challenge for orthopedic surgeons, and despite numerous biomechanical studies, the optimal implant is still controversial [1][2][3][4]. However, while plates with angular stability and retrograde interlocking nails are nowadays the best choice for treatment, CBP and DCS were the most used implants until the development of these innovative implants [5].In a biomechanical study from 2009, the authors compared the mechanical rigidity of the bone/implant (DCS or CBP) construct in complex supracondylar femoral fractures [5,6].Twelve synthetic composite femoral bones were fixed in the distal part with six DCS and six CBP, and then, the authors performed by osteotomy a bone defect of 1.5 cm to simulate a complex supracondylar fracture type A3/AO (Figure 1).The femurs were sectioned in the midshaft, and the proximal part of the distal fragments was fixed in a metallic adapter sleeve. The bone-implant constructs were tested for seven types of loading: (1) internal compression; (2) external compression; (3) anterior compression; (4) posterior compression; (5) axial compression; (6) external torsion; and (7) internal torsion.The compression tests were realized up to 350 N, and the applied torsion attended 25 Nm. The tests were repeated six times in order to establish the statistic dispersion. All the measurements for DCS were realized with or without compaction screw.The compression force and loading force were measured by a M221B04 (PCB Piezotronics force transducer), while linear deformation values for the compression were measured using two inductive transducers applied in frontal axis (TD1) and sagittal axis (TD2) (Figure 2). Data acquisition was realized by a six-channel admittance bridge, an interface board, and a digital data acquisition system DAQ1200 connected to a laptop.According to study measurements, by reporting the loading/unloading force to the transducer (TD1 and TD2) displacement, we represented hysteresis cycles as diagrams for the femur/DCS (with and without compaction screw)...